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Sample records for cdte solar cells

  1. The effect of excitons on CdTe solar cells

    International Nuclear Information System (INIS)

    Karazhanov, S. Zh.; Zhang, Y.; Mascarenhas, A.; Deb, S.

    2000-01-01

    Temperature and doping-level dependence of CdTe solar cells is investigated, taking into account the involvement of excitons on photocurrent transport. We show that the density of excitons in CdTe is comparable with that of minority carriers at doping levels ≥10 15 cm -3 . From the investigation of the dark-saturation current, we show that the product of electron and hole concentrations at equilibrium is several orders of magnitude more than the square of the intrinsic carrier concentration. With this assumption, we have studied the effect of excitons on CdTe solar cells, and the effect is negative. CdTe solar cell performance with excitons included agrees well with existing experimental results. (c) 2000 American Institute of Physics

  2. High-Efficiency, Commercial Ready CdTe Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Sites, James R. [Colorado State Univ., Fort Collins, CO (United States)

    2015-11-19

    Colorado State’s F-PACE project explored several ways to increase the efficiency of CdTe solar cells and to better understand the device physics of those cells under study. Increases in voltage, current, and fill factor resulted in efficiencies above 17%. The three project tasks and additional studies are described in detail in the final report. Most cells studied were fabricated at Colorado State using an industry-compatible single-vacuum closed-space-sublimation (CSS) chamber for deposition of the key semiconductor layers. Additionally, some cells were supplied by First Solar for comparison purposes, and a small number of modules were supplied by Abound Solar.

  3. CDTE alloys and their application for increasing solar cell performance

    Science.gov (United States)

    Swanson, Drew E.

    Cadmium Telluride (CdTe) thin film solar is the largest manufactured solar cell technology in the United States and is responsible for one of the lowest costs of utility scale solar electricity at a purchase agreement of $0.0387/kWh. However, this cost could be further reduced by increasing the cell efficiency. To bridge the gap between the high efficiency technology and low cost manufacturing, a research and development tool and process was built and tested. This fully automated single vacuum PV manufacturing tool utilizes multiple inline close space sublimation (CSS) sources with automated substrate control. This maintains the proven scalability of the CSS technology and CSS source design but with the added versatility of independent substrate motion. This combination of a scalable deposition technology with increased cell fabrication flexibility has allowed for high efficiency cells to be manufactured and studied. The record efficiency of CdTe solar cells is lower than fundamental limitations due to a significant deficit in voltage. It has been modeled that there are two potential methods of decreasing this voltage deficiency. The first method is the incorporation of a high band gap film at the back contact to induce a conduction-band barrier that can reduce recombination by reflecting electrons from the back surface. The addition of a Cd1-x MgxTe (CMT) layer at the back of a CdTe solar cell should induce this desired offset and reflect both photoelectrons and forward-current electrons away from the rear surface. Higher collection of photoelectrons will increase the cells current and the reduction of forward current will increase the cells voltage. To have the optimal effect, CdTe must have reasonable carrier lifetimes and be fully depleted. To achieve this experimentally, CdTe layers have been grown sufficiently thin to help produce a fully depleted cell. A variety of measurements including performance curves, transmission electron microscopy, x

  4. Metastability and reliability of CdTe solar cells

    Science.gov (United States)

    Guo, Da; Brinkman, Daniel; Shaik, Abdul R.; Ringhofer, Christian; Vasileska, Dragica

    2018-04-01

    Thin-film modules of all technologies often suffer from performance degradation over time. Some of the performance changes are reversible and some are not, which makes deployment, testing, and energy-yield prediction more challenging. Manufacturers devote significant empirical efforts to study these phenomena and to improve semiconductor device stability. Still, understanding the underlying reasons of these instabilities remains clouded due to the lack of ability to characterize materials at atomistic levels and the lack of interpretation from the most fundamental material science. The most commonly alleged causes of metastability in CdTe devices, such as ‘migration of Cu’, have been investigated rigorously over the past fifteen years. Still, the discussion often ended prematurely with stating observed correlations between stress conditions and changes in atomic profiles of impurities or CV doping concentration. Multiple hypotheses suggesting degradation of CdTe solar cell devices due to interaction and evolution of point defects and complexes were proposed, and none of them received strong theoretical or experimental confirmation. It should be noted that atomic impurity profiles in CdTe provide very little intelligence on active doping concentrations. The same elements could form different energy states, which could be either donors or acceptors, depending on their position in crystalline lattice. Defects interact with other extrinsic and intrinsic defects; for example, changing the state of an impurity from an interstitial donor to a substitutional acceptor often is accompanied by generation of a compensating intrinsic interstitial donor defect. Moreover, all defects, intrinsic and extrinsic, interact with the electrical potential and free carriers so that charged defects may drift in the electric field and the local electrical potential affects the formation energy of the point defects. Such complexity of interactions in CdTe makes understanding of temporal

  5. Impedance spectroscopy of CdTe thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Charlotte; Heisler, Christoph; Reisloehner, Udo; Ronning, Carsten; Wesch, Werner [Institute of Solid State Physics, University of Jena, Max-Wien-Platz 1, D-07743 Jena (Germany)

    2012-07-01

    Impedance Spectroscopy (IS) is a widely used method to analyze dielectric properties of specimen as a function of frequency. Typically this characterization method delivers an equivalent circuit diagram of the device under examination to describe its electrical properties. Traditionally IS is used in coating evaluation, corrosion monitoring and in electrochemistry. During the last years the method became more important also in the field of electrical characterization of solar cells. In our work we use IS for the electrical characterization of thin film CdTe solar cells. The measurement is done at room temperature without illumination in a frequency domain from 20 Hz to 2 MHz. The samples are measured under variable forward bias. The results match insufficiently with the model of two resistor-capacitor circuits in series which is commonly used to describe the p-n junction and the blocking back contact. For better consistency, other models from the literature are used and discussed. From the results a conclusion is drawn about the properties of the solar cell such as the nature of the p-n junction or the performance of the back contact.

  6. Doping of polycrystalline CdTe for high-efficiency solar cells on flexible metal foil.

    Science.gov (United States)

    Kranz, Lukas; Gretener, Christina; Perrenoud, Julian; Schmitt, Rafael; Pianezzi, Fabian; La Mattina, Fabio; Blösch, Patrick; Cheah, Erik; Chirilă, Adrian; Fella, Carolin M; Hagendorfer, Harald; Jäger, Timo; Nishiwaki, Shiro; Uhl, Alexander R; Buecheler, Stephan; Tiwari, Ayodhya N

    2013-01-01

    Roll-to-roll manufacturing of CdTe solar cells on flexible metal foil substrates is one of the most attractive options for low-cost photovoltaic module production. However, various efforts to grow CdTe solar cells on metal foil have resulted in low efficiencies. This is caused by the fact that the conventional device structure must be inverted, which imposes severe restrictions on device processing and consequently limits the electronic quality of the CdTe layer. Here we introduce an innovative concept for the controlled doping of the CdTe layer in the inverted device structure by means of evaporation of sub-monolayer amounts of Cu and subsequent annealing, which enables breakthrough efficiencies up to 13.6%. For the first time, CdTe solar cells on metal foil exceed the 10% efficiency threshold for industrialization. The controlled doping of CdTe with Cu leads to increased hole density, enhanced carrier lifetime and improved carrier collection in the solar cell. Our results offer new research directions for solving persistent challenges of CdTe photovoltaics.

  7. Emitter/absorber interface of CdTe solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Song, Tao, E-mail: tsong241@gmail.com; Sites, James R. [Physics Department, Colorado State University, Fort Collins, Colorado 80523 (United States); Kanevce, Ana [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

    2016-06-21

    The performance of CdTe solar cells can be very sensitive to the emitter/absorber interface, especially for high-efficiency cells with high bulk lifetime. Performance losses from acceptor-type interface defects can be significant when interface defect states are located near mid-gap energies. Numerical simulations show that the emitter/absorber band alignment, the emitter doping and thickness, and the defect properties of the interface (i.e., defect density, defect type, and defect energy) can all play significant roles in the interface recombination. In particular, a type I heterojunction with small conduction-band offset (0.1 eV ≤ ΔE{sub C} ≤ 0.3 eV) can help maintain good cell efficiency in spite of high interface defect density, much like with Cu(In,Ga)Se{sub 2} (CIGS) cells. The basic principle is that positive ΔE{sub C}, often referred to as a “spike,” creates an absorber inversion and hence a large hole barrier adjacent to the interface. As a result, the electron-hole recombination is suppressed due to an insufficient hole supply at the interface. A large spike (ΔE{sub C} ≥ 0.4 eV), however, can impede electron transport and lead to a reduction of photocurrent and fill-factor. In contrast to the spike, a “cliff” (ΔE{sub C} < 0 eV) allows high hole concentration in the vicinity of the interface, which will assist interface recombination and result in a reduced open-circuit voltage. Another way to mitigate performance losses due to interface defects is to use a thin and highly doped emitter, which can invert the absorber and form a large hole barrier at the interface. CdS is the most common emitter material used in CdTe solar cells, but the CdS/CdTe interface is in the cliff category and is not favorable from the band-offset perspective. The ΔE{sub C} of other n-type emitter choices, such as (Mg,Zn)O, Cd(S,O), or (Cd,Mg)Te, can be tuned by varying the elemental ratio for an optimal positive value of ΔE{sub C}. These

  8. Recent Developments of Flexible CdTe Solar Cells on Metallic Substrates: Issues and Prospects

    Directory of Open Access Journals (Sweden)

    M. M. Aliyu

    2012-01-01

    Full Text Available This study investigates the key issues in the fabrication of CdTe solar cells on metallic substrates, their trends, and characteristics as well as effects on solar cell performance. Previous research works are reviewed while the successes, potentials, and problems of such technology are highlighted. Flexible solar cells offer several advantages in terms of production, cost, and application over glass-based types. Of all the metals studied as substrates for CdTe solar cells, molybdenum appears the most favorable candidate, while close spaced sublimation (CSS, electrodeposition (ED, magnetic sputtering (MS, and high vacuum thermal evaporation (HVE have been found to be most common deposition technologies used for CdTe on metal foils. The advantages of these techniques include large grain size (CSS, ease of constituent control (ED, high material incorporation (MS, and low temperature process (MS, HVE, ED. These invert-structured thin film CdTe solar cells, like their superstrate counterparts, suffer from problems of poor ohmic contact at the back electrode. Thus similar strategies are applied to minimize this problem. Despite the challenges faced by flexible structures, efficiencies of up to 13.8% and 7.8% have been achieved in superstrate and substrate cell, respectively. Based on these analyses, new strategies have been proposed for obtaining cheaper, more efficient, and viable flexible CdTe solar cells of the future.

  9. Thin film CdTe solar cells by close spaced sublimation: Recent results from pilot line

    International Nuclear Information System (INIS)

    Siepchen, B.; Drost, C.; Späth, B.; Krishnakumar, V.; Richter, H.; Harr, M.; Bossert, S.; Grimm, M.; Häfner, K.; Modes, T.; Zywitzki, O.; Morgner, H.

    2013-01-01

    CdTe is an attractive material to produce high efficient and low cost thin film solar cells. The semiconducting layers of this kind of solar cell can be deposited by the Close Spaced Sublimation (CSS) process. The advantages of this technique are high deposition rates and an excellent utilization of the raw material, leading to low production costs and competitive module prices. CTF Solar GmbH is offering equipment and process knowhow for the production of CdTe solar modules. For further improvement of the technology, research is done at a pilot line, which covers all relevant process steps for manufacture of CdTe solar cells. Herein, we present the latest results from the process development and our research activities on single functional layers as well as for complete solar cell devices. Efficiencies above 13% have already been obtained with Cu-free back contacts. An additional focus is set on different transparent conducting oxide materials for the front contact and a Sb 2 Te 3 based back contact. - Highlights: ► Laboratory established on industrial level for CdTe solar cell research ► 13.0% cell efficiency with our standard front contact and Cu-free back contact ► Research on ZnO-based transparent conducting oxide and Sb 2 Te 3 back contacts ► High resolution scanning electron microscopy analysis of ion polished cross section

  10. Design Strategies for High-Efficiency CdTe Solar Cells

    Science.gov (United States)

    Song, Tao

    With continuous technology advances over the past years, CdTe solar cells have surged to be a leading contributor in thin-film photovoltaic (PV) field. While empirical material and device optimization has led to considerable progress, further device optimization requires accurate device models that are able to provide an in-depth understanding of CdTe device physics. Consequently, this thesis is intended to develop a comprehensive model system for high-efficiency CdTe devices through applying basic design principles of solar cells with numerical modeling and comparing results with experimental CdTe devices. The CdTe absorber is central to cell performance. Numerical simulation has shown the feasibility of high energy-conversion efficiency, which requires both high carrier density and long minority carrier lifetime. As the minority carrier lifetime increases, the carrier recombination at the back surface becomes a limitation for cell performance with absorber thickness cell performance, since it can induce a large valence-band bending which suppresses the hole injection near the interface for the electron-hole recombination, but too large a spike is detrimental to photocurrent transport. In a heterojunction device with many defects at the emitter/absorber interface (high SIF), a thin and highly-doped emitter can induce strong absorber inversion and hence help maintain good cell performance. Performance losses from acceptor-type interface defects can be significant when interface defect states are located near mid-gap energies. In terms of specific emitter materials, the calculations suggest that the (Mg,Zn)O alloy with 20% Mg, or a similar type-I heterojunction partner with moderate DeltaE C (e.g., Cd(S,O) or (Cd,Mg)Te with appropriate oxygen or magnesium ratios) should yield higher voltages and would therefore be better candidates for the CdTe-cell emitter. The CdTe/substrate interface is also of great importance, particularly in the growth of epitaxial

  11. An optimized multilayer structure of CdS layer for CdTe solar cells application

    International Nuclear Information System (INIS)

    Han Junfeng; Liao Cheng; Jiang Tao; Spanheimer, C.; Haindl, G.; Fu, Ganhua; Krishnakumar, V.; Zhao Kui; Klein, A.; Jaegermann, W.

    2011-01-01

    Research highlights: → Two different methods to prepare CdS films for CdTe solar cells. → A new multilayer structure of window layer for the CdTe solar cell. → Thinner CdS window layer for the solar cell than the standard CdS layer. → Higher performance of solar cells based on the new multilayer structure. - Abstract: CdS layers grown by 'dry' (close space sublimation) and 'wet' (chemical bath deposition) methods are deposited and analyzed. CdS prepared with close space sublimation (CSS) has better crystal quality, electrical and optical properties than that prepared with chemical bath deposition (CBD). The performance of CdTe solar cell based on the CSS CdS layer has higher efficiency than that based on CBD CdS layer. However, the CSS CdS suffers from the pinholes. And consequently it is necessary to prepare a 150 nm thin film for CdTe/CdS solar cell. To improve the performance of CdS/CdTe solar cells, a thin multilayer structure of CdS layer (∼80 nm) is applied, which is composed of a bottom layer (CSS CdS) and a top layer (CBD CdS). That bi-layer film can allow more photons to pass through it and significantly improve the short circuit current of the CdS/CdTe solar cells.

  12. Optimization of material/device parameters of CdTe photovoltaic for solar cells applications

    Science.gov (United States)

    Wijewarnasuriya, Priyalal S.

    2016-05-01

    Cadmium telluride (CdTe) has been recognized as a promising photovoltaic material for thin-film solar cell applications due to its near optimum bandgap of ~1.5 eV and high absorption coefficient. The energy gap is near optimum for a single-junction solar cell. The high absorption coefficient allows films as thin as 2.5 μm to absorb more than 98% of the above-bandgap radiation. Cells with efficiencies near 20% have been produced with poly-CdTe materials. This paper examines n/p heterostructure device architecture. The performance limitations related to doping concentrations, minority carrier lifetimes, absorber layer thickness, and surface recombination velocities at the back and front interfaces is assessed. Ultimately, the paper explores device architectures of poly- CdTe and crystalline CdTe to achieve performance comparable to gallium arsenide (GaAs).

  13. A computational study on the energy bandgap engineering in performance enhancement of CdTe thin film solar cells

    Directory of Open Access Journals (Sweden)

    Ameen M. Ali

    Full Text Available In this study, photovoltaic properties of CdTe thin film in the configuration of n-SnO2/n-CdS/p-CdTe/p-CdTe:Te/metal have been studied by numerical simulation software named “Analysis of Microelectronic and Photonic Structure” (AMPS-1D. A modified structure for CdTe thin film solar cell has been proposed by numerical analysis with the insertion of a back contact buffer layer (CdTe:Te. This layer can serve as a barrier that will decelerate the copper diffusion in CdTe solar cell. Four estimated energy bandgap relations versus the Tellurium (Te concentrations and the (CdTe:Te layer thickness have been examined thoroughly during simulation. Correlation between energy bandgap with the CdTe thin film solar cell performance has also been established. Keywords: Numerical modelling, CdTe thin film, Solar cell, AMPS-1D, Bandgap

  14. Physical vapor deposition of CdTe thin films at low temperature for solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Heisler, Christoph; Brueckner, Michael; Lind, Felix; Kraft, Christian; Reisloehner, Udo; Ronning, Carsten; Wesch, Werner [Institute of Solid State Physics, University of Jena, Max-Wien-Platz 1, D-07743 Jena (Germany)

    2012-07-01

    Cadmium telluride is successfully utilized as an absorber material for thin film solar cells. Industrial production makes use of high substrate temperatures for the deposition of CdTe absorber layers. However, in order to exploit flexible substrates and to simplify the manufacturing process, lower deposition temperatures are beneficial. Based on the phase diagram of CdTe, predictions on the stoichiometry of CdTe thin films grown at low substrate temperatures are made in this work. These predictions were verified experimentally using additional sources of Cd and Te during the deposition of the CdTe thin films at different substrate temperatures. The deposited layers were analyzed with energy-dispersive X-ray spectroscopy. In case of CdTe layers which were deposited at substrate temperatures lower than 200 C without usage of additional sources we found a non-stoichiometric growth of the CdTe layers. The application of the additional sources leads to a stoichiometric growth for substrate temperatures down to 100 C which is a significant reduction of the substrate temperature during deposition.

  15. The next generation CdTe technology- Substrate foil based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ferekides, Chris [Univ. of South Florida, Tampa, FL (United States)

    2017-03-22

    The main objective of this project was the development of one of the most promising Photovoltaic (PV) materials CdTe into a versatile, cost effective, and high throughput technology, by demonstrating substrate devices on foil substrates using high throughput fabrication conditions. The typical CdTe cell is of the superstrate configuration where the solar cell is fabricated on a glass superstrate by the sequential deposition of a TCO, n-type heterojunction partner, p-CdTe absorber, and back contact. Large glass modules are heavy and present significant challenges during manufacturing (uniform heating, etc.). If a substrate CdTe cell could be developed (the main goal of this project) a roll-to-toll high throughput technology could be developed.

  16. Influence of the layer parameters on the performance of the CdTe solar cells

    Science.gov (United States)

    Haddout, Assiya; Raidou, Abderrahim; Fahoume, Mounir

    2018-03-01

    Influence of the layer parameters on the performances of the CdTe solar cells is analyzed by SCAPS-1D. The ZnO: Al film shows a high efficiency than SnO2:F. Moreover, the thinner window layer and lower defect density of CdS films are the factor in the enhancement of the short-circuit current density. As well, to increase the open-circuit voltage, the responsible factors are low defect density of the absorbing layer CdTe and high metal work function. For the low cost of cell production, ultrathin film CdTe cells are used with a back surface field (BSF) between CdTe and back contact, such as PbTe. Further, the simulation results show that the conversion efficiency of 19.28% can be obtained for the cell with 1-μm-thick CdTe, 0.1-μm-thick PbTe and 30-nm-thick CdS.

  17. Growth and analysis of micro and nano CdTe arrays for solar cell applications

    Science.gov (United States)

    Aguirre, Brandon Adrian

    CdTe is an excellent material for infrared detectors and photovoltaic applications. The efficiency of CdTe/CdS solar cells has increased very rapidly in the last 3 years to ˜20% but is still below the maximum theoretical value of 30%. Although the short-circuit current density is close to its maximum of 30 mA/cm2, the open circuit voltage has potential to be increased further to over 1 Volt. The main limitation that prevents further increase in the open-circuit voltage and therefore efficiency is the high defect density in the CdTe absorber layer. Reducing the defect density will increase the open-circuit voltage above 1 V through an increase in the carrier lifetime and concentration to tau >10 ns and p > 10 16 cm-3, respectively. However, the large lattice mismatch (10%) between CdTe and CdS and the polycrystalline nature of the CdTe film are the fundamental reasons for the high defect density and pose a difficult challenge to solve. In this work, a method to physically and electrically isolate the different kinds of defects at the nanoscale and understand their effect on the electrical performance of CdTe is presented. A SiO2 template with arrays of window openings was deposited between the CdTe and CdS to achieve selective-area growth of the CdTe via close-space sublimation. The diameter of the window openings was varied from the micro to the nanoscale to study the effect of size on nucleation, grain growth, and defect density. The resulting structures enabled the possibility to electrically isolate and individually probe micrometer and nanoscale sized CdTe/CdS cells. Electron back-scattered diffraction was used to observe grain orientation and defects in the miniature cells. Scanning and transmission electron microscopy was used to study the morphology, grain boundaries, grain orientation, defect structure, and strain in the layers. Finally, conducting atomic force microscopy was used to study the current-voltage characteristics of the solar cells. An

  18. Polycrystalline CdTe solar cells on elastic substrates

    International Nuclear Information System (INIS)

    Sibinski, M.; Lisik, Z.

    2007-01-01

    The presented article is a report on progress in photovoltaic devices and material processing. A cadmium telluride solar cell as one of the most attractive option for thin-film polycrystalline cell constructions is presented. All typical manufacturing steps of this device, including recrystallisation and junction activation are explained. A new potential field of application for this kind of device - the BIPV (Building Integrated Photovoltaic) is named and discussed. All possible configuration options for this application, according to material properties and exploitation demands are considered. The experimental part of the presented paper is focused on practical implementation of the high - temperature polymer foil as the substrate of the newly designed device by the help of ICSVT (Isothermal Close Space Vapour Transport) technique. The evaluation of the polyester and polyamide foils according to the ICSVT/CSS manufacturing process parameters is described and discussed. A final conclusion on practical verification of these materials is also given. (authors)

  19. Technical evaluation of Solar Cells, Inc., CdTe module and array at NREL

    Energy Technology Data Exchange (ETDEWEB)

    Kroposki, B.; Strand, T.; Hansen, R. [National Renewable Energy Lab., Golden, CO (United States); Powell, R.; Sasala, R. [Solar Cells, Inc., Toledo, OH (United States)

    1996-05-01

    The Engineering and Technology Validation Team at the National Renewable Energy Laboratory (NREL) conducts in-situ technical evaluations of polycrystalline thin-film photovoltaic (PV) modules and arrays. This paper focuses on the technical evaluation of Solar Cells, Inc., (SCI) cadmium telluride (CdTe) module and array performance by attempting to correlate individual module and array performance. This is done by examining the performance and stability of the modules and array over a period of more than one year. Temperature coefficients for module and array parameters (P{sub max}, V{sub oc}, V{sub max}, I{sub sc}, I{sub max}) are also calculated.

  20. Novel Contact Materials for Improved Performance CdTe Solar Cells Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Rockett, Angus [Colorado School of Mines, Golden, CO (United States); Marsillac, Sylvain [Old Dominion Univ., Norfolk, VA (United States); Collins, Robert [Univesity of Toledo

    2018-04-15

    This program has explored a number of novel materials for contacts to CdTe solar cells in order to reduce the back contact Schottky barrier to zero and produce an ohmic contact. The project tested a wide range of potential contact materials including TiN, ZrN, CuInSe2:N, a-Si:H and alloys with C, and FeS2. Improved contacts were achieved with FeS2. As part of understanding the operation of the devices and controlling the deposition processes, a number of other important results were obtained. In the process of this project and following its conclusion it led to research that resulted in seven journal articles, nine conference publications, 13 talks presented at conferences, and training of eight graduate students. The seven journal articles were published in 2015, 2016, and 2017 and have been cited, as of March 2018, 52 times (one cited 19 times and two cited 11 times). We demonstrated high levels of doping of CIS with N but electrical activity of the resulting N was not high and the results were difficult to reproduce. Furthermore, even with high doping the contacts were not good. Annealing did not improve the contacts. A-Si:H was found to produce acceptable but unstable contacts, degrading even over a day or two, apparently due to H incorporation into the CdTe. Alloying with C did not improve the contacts or stability. The transition metal nitrides produced Schottky type contacts for all materials tested. While these contacts were found to be unsatisfactory, we investigated FeS2 and found this material to be effective and comparable to the best contacts currently available. The contacts were found to be chemically stable under heat treatment and preferable to Cu doped contacts. Thus, we demonstrated an improved contact material in the course of this project. In addition, we developed new ways of controlling the deposition of CdTe and other materials, demonstrated the nature of defects in CdTe, and studied the distribution of conductivity and carrier type in CdTe

  1. Performance and Metastability of CdTe Solar Cells with a Te Back-Contact Buffer Layer

    Science.gov (United States)

    Moore, Andrew

    Thin-film CdTe photovoltaics are quickly maturing into a viable clean-energy solution through demonstration of competitive costs and performance stability with existing energy sources. Over the last half decade, CdTe solar technology has achieved major gains in performance; however, there are still aspects that can be improved to progress toward their theoretical maximum efficiency. Perhaps equally valuable as high photovoltaic efficiency and a low levelized cost of energy, is device reliability. Understanding the root causes for changes in performance is essential for accomplishing long-term stability. One area for potential performance enhancement is the back contact of the CdTe device. This research incorporated a thin-film Te-buffer layer into the contact structure, between the CdTe and contact metal. The device performance and characteristics of many different back contact configurations were rigorously studied. CdTe solar cells fabricated with the Te-buffer contact showed short-circuit current densities and open-circuit voltages that were on par with the traditional back-contacts used at CSU. However, the Te-buffer contact typically produced 2% larger fill-factors on average, leading to greater conversation efficiency. Furthermore, using the Te buffer allowed for incorporation of 50% less Cu, which is used for p-type doping but is also known to decrease lifetime and stability. This resulted in an additional 3% fill-factor gain with no change in other parameters compared to the standard-Cu treated device. In order to better understand the physical mechanisms of the Te-buffer contact, electrical and material properties of the Te layer were extracted and used to construct a simple energy band diagram. The Te layer was found to be highly p-type (>1018 cm-3) and possess a positive valence-band offset of 0.35-0.40 eV with CdTe. An existing simulation model incorporating the Te-layer properties was implemented and validated by comparing simulated results of CdTe

  2. Development of MoOx thin films as back contact buffer for CdTe solar cells in substrate configuration

    International Nuclear Information System (INIS)

    Gretener, C.; Perrenoud, J.; Kranz, L.; Baechler, C.; Yoon, S.; Romanyuk, Y.E.; Buecheler, S.; Tiwari, A.N.

    2013-01-01

    Molybdenum oxide compounds exhibit unique electrical and optical properties depending on oxygen vacancy concentration and composition and therefore, have recently attracted a lot of attention as a hole transport layer in various devices. In this work CdTe solar cells in substrate configuration were grown with evaporated MoO x back contact buffer layers and efficiencies of up to 10% could be achieved without using Cu in the back contact processing. The buffer layer – at the CdTe/back contact interface – in the finished cell was found to consist of MoO 2 phase instead of the expected MoO 3 phase as observed in as-deposited or annealed MoO x layers without CdTe deposition. In order to obtain MoO x buffer layers with desired stoichiometry, MoO x thin films were deposited by radio-frequency sputtering under different growth conditions. The chemical phase, composition, microstructure and optical properties of such layers were studied for their possible use in CdTe solar cells. - Highlights: ► MoO x is used as a back contact buffer in CdTe solar cells in substrate configuration. ► Efficiency of 10.0% was achieved without the addition of Cu. ► The back contact buffer in the finished device consists only of MoO 2 . ► Phases and microstructure of MoO x can be controlled by sputtering conditions

  3. Research and development of CdTe based thin film PV solar cells

    Science.gov (United States)

    Diso, Dahiru Garba

    The motivation behind this research is to bring cheap, low-cost and clean energy technologies to the society. Colossal use of fossil fuel has created noticeable pollution problems contributing to climate change and health hazards. Silicon based solar cells have dominated the market but it is cost is high due to the manufacturing process. Therefore, the way forward is to develop thin films solar cells using low-cost attractive materials, grown by cheaper, scalable and manufacturable techniques.The aim and objectives of this work is to develop low-cost, high efficiency solar cell using electrodeposition (ED) technique. The material layers include CdS and ZnTe as the window materials, while the absorber material is CdTe. Fabricating a suitable devices for solar energy conversion (i.e. glass/conducting glass/window material/absorber material/metal) structure. Traditional way of fabricating this structure is to grow window material (CdS) using chemical bath deposition (CBD) and absorber material (CdTe) using electrodeposition. However, CBD is a batch process and therefore creates large volumes of Cd-containing waste solutions each time adding high cost in manufacturing process. This research programme is therefore on development of an "All ED-solar cells" structure.Material studies were carried out using photoelectrochemical (PEC) studies, UV-Vis spectrophotometry, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Furthermore, the electrical characterisation of fully fabricated devices was performed using current-voltage (I-V) and capacitance-voltage (C-V) measurements.This research programme has demonstrated that CdS and ZnTe window materials can be electrodeposited and used in thin film solar cell devices. The CdS electrolytic bath can be used for a period of 7 months without discarding it like in the CBD process which usually has life

  4. Enhancement in microstructural and optoelectrical properties of thermally evaporated CdTe films for solar cells

    Science.gov (United States)

    Chander, Subhash; Dhaka, M. S.

    2018-03-01

    The optimization of microstructural and optoelectrical properties of a thin layer is an important step prior device fabrication process, so an enhancement in these properties of thermally evaporated CdTe thin films is reported in this communication. The films having thickness 450 nm and 850 nm were deposited on thoroughly cleaned glass and indium tin oxide (ITO) substrates followed by annealing at 450 °C in air atmosphere. These films were characterized for microstructural and optoelectrical properties employing X-ray diffraction, scanning electron microscopy coupled with energy-dispersive spectroscopy, UV-Vis spectrophotometer and source meter. The films found to be have zinc-blende cubic structure with preferred reflection (111) while the crystallographic parameters and direct energy band gap are strongly influenced by the film thickness. The surface morphology studies show that the films are uniform, smooth, homogeneous and nearly dense-packed as well as free from voids and pitfalls as where elemental analysis revealed the presence of Cd and Te element in the deposited films. The electrical analysis showed linear behavior of current with voltage while conductivity is decreased for higher thickness. The results show that the microstructural and optoelectrical properties of CdTe thin layer could be enhanced by varying thickness and films having higher thickness might be processed as promising absorber thin layer to the CdTe-based solar cells.

  5. Growth and characterization of CdTe absorbers on GaAs by MBE for high concentration PV solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ari, Ozan; Polat, Mustafa; Selamet, Yusuf [Department of Physics, Izmir Institute of Technology, Izmir 35430 (Turkey); Karakaya, Merve [Department of Material Science and Engineering, Izmir Institute of Technology, Izmir 35430 (Turkey)

    2015-11-15

    CdTe based II-VI absorbers are promising candidates for high concentration PV solar cells with an ideal band gap for AM1.5 solar radiation. In this study, we propose single crystal CdTe absorbers grown on GaAs substrates with a molecular beam epitaxy (MBE) which is a clean deposition technology. We show that high quality CdTe absorber layers can be grown with full width half maximum of X-ray diffraction rocking curves (XRD RC) as low as 227 arc-seconds with 0.5% thickness uniformity that a 2 μm layer is capable of absorbing 99% of AM1.5 solar radiation. Bandgap of the CdTe absorber is found as 1.483 eV from spetroscopic ellipsometry (SE) measurements. Also, high absorption coefficient is calculated from the results, which is ∝5 x 10{sup 5}cm{sup -1} in solar radiation spectrum. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Effects of CdCl2 on the growth of CdTe on CdS films for solar cells by isothermal close-spaced vapor transport

    International Nuclear Information System (INIS)

    Vaccaro, P.O.; Meyer, G.O.; Saura, J.

    1991-01-01

    CdS/CdTe solar cells were made by depositing CdTe films by an isothermal close-spaced vapor transport method on sintered CdS/glass substrates. The influence of amounts of CdCl2 ranging from 0 wt% to 8 wt% in the CdTe source on the solar cells performance was studied. Increasing the CdCl2 content enhances the CdTe grainsize but degrades the spectral response and increases the reverse saturation current. An optimal CdCl2 concentration of 1 wt% was found for a growth temperature of 620 deg C. (Author)

  7. Numerical Analysis of Novel Back Surface Field for High Efficiency Ultrathin CdTe Solar Cells

    Directory of Open Access Journals (Sweden)

    M. A. Matin

    2013-01-01

    Full Text Available This paper numerically explores the possibility of high efficiency, ultrathin, and stable CdTe cells with different back surface field (BSF using well accepted simulator AMPS-1D (analysis of microelectronics and photonic structures. A modified structure of CdTe based PV cell SnO2/Zn2SnO4/CdS/CdTe/BSF/BC has been proposed over reference structure SnO2/Zn2SnO4/CdS/CdTe/Cu. Both higher bandgap materials like ZnTe and Cu2Te and low bandgap materials like As2Te3 and Sb2Te3 have been used as BSF to reduce minority carrier recombination loss at the back contact in ultra-thin CdTe cells. In this analysis the highest conversion efficiency of CdTe based PV cell without BSF has been found to be around 17% using CdTe absorber thickness of 5 μm. However, the proposed structures with different BSF have shown acceptable efficiencies with an ultra-thin CdTe absorber of only 0.6 μm. The proposed structure with As2Te3 BSF showed the highest conversion efficiency of 20.8% ( V,  mA/cm2, and . Moreover, the proposed structures have shown improved stability in most extents, as it was found that the cells have relatively lower negative temperature coefficient. However, the cell with ZnTe BSF has shown better overall stability than other proposed cells with temperature coefficient (TC of −0.3%/°C.

  8. High short-circuit current density CdTe solar cells using all-electrodeposited semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Echendu, O.K., E-mail: oechendu@yahoo.com; Fauzi, F.; Weerasinghe, A.R.; Dharmadasa, I.M.

    2014-04-01

    CdS/CdTe and ZnS/CdTe n–n heterojunction solar cells have been fabricated using all-electrodeposited semiconductors. The best devices show remarkable high short-circuit current densities of 38.5 mAcm{sup −2} and 47.8 mAcm{sup −2}, open-circuit voltages of 630 mV and 646 mV and conversion efficiencies of 8.0% and 12.0% respectively. The major strength of these device structures lies in the combination of n–n heterojunction with a large Schottky barrier at the n-CdTe/metal back contact which provides the required band bending for the separation of photo-generated charge carriers. This is in addition to the use of a high quality n-type CdTe absorber layer with high electron mobility. The potential barrier heights estimated for these devices from the current–voltage characteristics exceed 1.09 eV and 1.13 eV for CdS/CdTe and ZnS/CdTe cells respectively. The diode rectification factors of both devices are in excess of four orders of magnitude with reverse saturation current densities of 1.0 × 10{sup −7} Acm{sup −2} and 4.0 × 10{sup −7} Acm{sup −2} respectively. These all-electrodeposited solar cell device structures are currently being studied and developed as an alternative to the well-known p–n junction structures which utilise chemical bath-deposited CdS. The preliminary material growth, device fabrication and assessment results are presented in this paper. - Highlights: • Two-electrode deposition. • High J{sub sc} Schottky barrier solar cells. • CdCl{sub 2} + CdF{sub 2} treatment.

  9. Spectroscopic study on the doping of polycrystalline CdTe layers for solar cells; Spektroskopische Untersuchungen zur Dotierung von polykristallinen CdTe-Schichten fuer Solarzellen

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, Christian

    2011-11-29

    First in the present thesis the fundamental properties of CdTe are described. In the following it is discussed, how a CdTe solar cell is generally constructed, which specialities are to be regarded, and how an improvement of the actually reachable data of such a solar cell in view of the efficiency can be reached fundamentally and in then practical realization. In the third chapter the physical foundations of the most important methods are discussed, which are applied in the framework of this thesis for the analysis of the CdTe layers. The fourth chapter describes the details of the experiments of this thesis. The fifth chapter deals with the analysis of the photoluminescence of CdTe layers. Special attention is put on the analysis of the excitonic luminescence. The sixth chapter treats the implantation of CdTe layers with phosphor. The influence of phosphorus as dopant on the PL spectra of CdTe and the correponding characteristics of implanted solar cells are presented. Also the influence of radiation damages as consequence of the ion implantation is studied in this chapter by means of the analysis of differently thick absorber layers. In the seventh chapter finally a new procedure for the fabrication of solar cells on the base of CdTe as absorber material is introduced, which shall make possible to change the stoichiometry of cadmium mand tellurium specifically and to present additionally a suited material, in order to form the doping of CdTE a solar-cell material variably. The fundamental properties of the new facility are experimentally determined, and first solar cells are fabricated with this facility and analyzed. Also an in-situ doping with phosphorus is thereby performed and the result studied.

  10. Effect of Annealing on the Properties of Antimony Telluride Thin Films and Their Applications in CdTe Solar Cells

    Directory of Open Access Journals (Sweden)

    Zhouling Wang

    2014-01-01

    Full Text Available Antimony telluride alloy thin films were deposited at room temperature by using the vacuum coevaporation method. The films were annealed at different temperatures in N2 ambient, and then the compositional, structural, and electrical properties of antimony telluride thin films were characterized by X-ray fluorescence, X-ray diffraction, differential thermal analysis, and Hall measurements. The results indicate that single phase antimony telluride existed when the annealing temperature was higher than 488 K. All thin films exhibited p-type conductivity with high carrier concentrations. Cell performance was greatly improved when the antimony telluride thin films were used as the back contact layer for CdTe thin film solar cells. The dark current voltage and capacitance voltage measurements were performed to investigate the formation of the back contacts for the cells with or without Sb2Te3 buffer layers. CdTe solar cells with the buffer layers can reduce the series resistance and eliminate the reverse junction between CdTe and metal electrodes.

  11. A low-cost non-toxic post-growth activation step for CdTe solar cells

    Science.gov (United States)

    Major, J. D.; Treharne, R. E.; Phillips, L. J.; Durose, K.

    2014-07-01

    Cadmium telluride, CdTe, is now firmly established as the basis for the market-leading thin-film solar-cell technology. With laboratory efficiencies approaching 20 per cent, the research and development targets for CdTe are to reduce the cost of power generation further to less than half a US dollar per watt (ref. 2) and to minimize the environmental impact. A central part of the manufacturing process involves doping the polycrystalline thin-film CdTe with CdCl2. This acts to form the photovoltaic junction at the CdTe/CdS interface and to passivate the grain boundaries, making it essential in achieving high device efficiencies. However, although such doping has been almost ubiquitous since the development of this processing route over 25 years ago, CdCl2 has two severe disadvantages; it is both expensive (about 30 cents per gram) and a water-soluble source of toxic cadmium ions, presenting a risk to both operators and the environment during manufacture. Here we demonstrate that solar cells prepared using MgCl2, which is non-toxic and costs less than a cent per gram, have efficiencies (around 13%) identical to those of a CdCl2-processed control group. They have similar hole densities in the active layer (9 × 1014 cm-3) and comparable impurity profiles for Cl and O, these elements being important p-type dopants for CdTe thin films. Contrary to expectation, CdCl2-processed and MgCl2-processed solar cells contain similar concentrations of Mg; this is because of Mg out-diffusion from the soda-lime glass substrates and is not disadvantageous to device performance. However, treatment with other low-cost chlorides such as NaCl, KCl and MnCl2 leads to the introduction of electrically active impurities that do compromise device performance. Our results demonstrate that CdCl2 may simply be replaced directly with MgCl2 in the existing fabrication process, thus both minimizing the environmental risk and reducing the cost of CdTe solar-cell production.

  12. Physical properties of Bi doped CdTe thin films grown by CSVT and their influence on the CdS/CdTe solar cells PV-properties

    International Nuclear Information System (INIS)

    Vigil-Galan, O.; Sanchez-Meza, E.; Ruiz, C.M.; Sastre-Hernandez, J.; Morales-Acevedo, A.; Cruz-Gandarilla, F.; Aguilar-Hernandez, J.; Saucedo, E.; Contreras-Puente, G.; Bermudez, V.

    2007-01-01

    The physical properties of Bi doped CdTe films, grown on glass substrates by the Closed Space Transport Vapour (CSVT) method, from different Bi doped CdTe powders are presented. The CdTe:Bi films were characterized using Photoluminescence, Hall effect, X-Ray diffraction, SEM and Photoconductivity measurements. Moreover, CdS/CdTe:Bi solar cells were made and their characteristics like short circuit current density (J sc ), open circuit voltage (V OC ), fill factor (FF) and efficiency (η) were determined. These devices were fabricated from Bi doped CdTe layers deposited on CdS with the same growth conditions than those used for the single CdTe:Bi layers. A correlation between the CdS/CdTe:Bi solar cell characteristics and the physical properties of the Bi doped CdTe thin films are presented and discussed

  13. Semiconductor interfaces of polycrystalline CdTe thin-film solar cells. Characterization and modification of electronic properties

    International Nuclear Information System (INIS)

    Fritsche, J.

    2003-01-01

    In this thesis for the first time the electronic properties of the semiconductor interfaces in polycrystalline CdTe thin-film solar cells, as well as the morphological and electronic properties of the single semiconductor surfaces were systematically characterized by surface-sensitive measuring methods. The morphological surface properties were analyzed by scanning force microscopy. As substrate materials with SnO 2 /ITO covered glass was applied, where the CdS and CdTe layers were deposited. Furthermore the electronic and morphological material properties of differently treated SnO 2 surfaces were characterized. Beside the studies with scanning force microscopy sputtering depth profiles and X-ray photoelectron spectroscopy were measured

  14. Electrical characterization of CdTe grain-boundary properties from as processed CdTe/CdS solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Woods, L.M.; Robinson, G.Y. [Colorado State Univ., Fort Collins, CO (United States); Levi, D.H.; Ahrenkiel, R.K. [National Renewable Energy Lab., Golden, CO (United States); Kaydanov, V. [Colorado School of Mines, Golden, CO (United States)

    1998-09-01

    An ability to liftoff or separate the thin-film polycrystalline CdTe from the CdS, without the use of chemical etches, has enabled direct electrical characterization of the as-processed CdTe near the CdTe/CdS heterointerface. The authors use this ability to understand how a back-contact, nitric-phosphoric (NP) etch affects the grain boundaries throughout the film. Quantitative determination of the grain-boundary barrier potentials and estimates of doping density near the grain perimeter are determined from theoretical fits to measurements of the current vs. temperature. Estimates of the bulk doping are determined from high-frequency resistivity measurements. The light and dark barrier potentials change after the NP etch, and the origin of this change is postulated. Also, a variable doping density within the grains of non-etched material has been determined. These results allow a semi-quantitative grain-boundary band diagram to be drawn that should aid in determining more accurate two-dimensional models for polycrystalline CdTe solar cells.

  15. Numerical dataset for analyzing the performance of a highly efficient ultrathin film CdTe solar cell

    Directory of Open Access Journals (Sweden)

    Rucksana Safa Sultana

    2017-06-01

    Full Text Available The article comprises numerical data of distinct semiconductor materials applied in the sketch of a CdTe absorber based ultrathin film solar cell. Additionally, the contact layer parametric values of the cell have been described also. Therefore, the simulation has been conducted with data related to the hetero-structured (n-ZnO/n-CdS/p-CdTe/p-ZnTe semiconductor device and a J–V characteristics curve was obtained. The operating conditions have also been recorded. Afterward, the solar cell performance parameters such as open circuit voltage (Voc, short circuit current density (Jsc, fill factor (FF, and efficiency (η have been investigated and compared with reference cell.

  16. Evolution of oxygenated cadmium sulfide (CdS:O) during high-temperature CdTe solar cell fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Meysing, Daniel M.; Reese, Matthew O.; Warren, Charles W.; Abbas, Ali; Burst, James M.; Mahabaduge, Hasitha P.; Metzger, Wyatt K.; Walls, John M.; Lonergan, Mark C.; Barnes, Teresa M.; Wolden, Colin A.

    2016-12-01

    Oxygenated cadmium sulfide (CdS:O) produced by reactive sputtering has emerged as a promising alternative to conventional CdS for use as the n-type window layer in CdTe solar cells. Here, complementary techniques are used to expose the window layer (CdS or CdS:O) in completed superstrate devices and combined with a suite of materials characterization to elucidate its evolution during high temperature device processing. During device fabrication amorphous CdS:O undergoes significant interdiffusion with CdTe and recrystallization, forming CdS1-yTey nanocrystals whose Te fraction approaches solubility limits. Significant oxygen remains after processing, concentrated in sulfate clusters dispersed among the CdS1-yTey alloy phase, accounting for ~30% of the post-processed window layer based on cross-sectional microscopy. Interdiffusion and recrystallization are observed in devices with un-oxygenated CdS, but to a much lesser extent. Etching experiments suggest that the CdS thickness is minimally changed during processing, but the CdS:O window layer is reduced from 100 nm to 60-80 nm, which is confirmed by microscopy. Alloying reduces the band gap of the CdS:O window layer to 2.15 eV, but reductions in thickness and areal density improve its transmission spectrum, which is well matched to device quantum efficiency. The changes to the window layer in the reactive environments of device fabrication are profoundly different than what occurs by thermal annealing in an inert environment, which produced films with a band gap of 2.4 eV for both CdS and CdS:O. These results illustrate for the first time the significant changes that occur to the window layer during processing that are critical to the performance of CdTe solar cells.

  17. The large-area CdTe thin film for CdS/CdTe solar cell prepared by physical vapor deposition in medium pressure

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Run; Liu, Bo; Yang, Xiaoyan; Bao, Zheng; Li, Bing, E-mail: libing70@126.com; Zhang, Jingquan; Li, Wei; Wu, Lili; Feng, Lianghuan

    2016-01-01

    Graphical abstract: - Highlights: • The large-area CdTe film has been prepared by PVD under the pressure of 0.9 kPa. • The as-prepared CdTe thin film processes excellent photovoltaic properties. • This technique is suitable for depositing large-area CdTe thin film. • The 14.6% champion efficiency CdS/CdTe cell has been achieved. - Abstract: The Cadmium telluride (CdTe) thin film has been prepared by physical vapor deposition (PVD), the Ar + O{sub 2} pressure is about 0.9 kPa. This method is a newer technique to deposit CdTe thin film in large area, and the size of the film is 30 × 40 cm{sup 2}. This method is much different from the close-spaced sublimation (CSS), as the relevance between the source temperature and the substrate temperature is weak, and the gas phase of CdTe is transferred to the substrate by Ar + O{sub 2} flow. Through this method, the compact and uniform CdTe film (30 × 40 cm{sup 2}) has been achieved, and the performances of the CdTe thin film have been determined by transmission spectrum, SEM and XRD. The film is observed to be compact with a good crystallinity, the CdTe is polycrystalline with a cubic structure and a strongly preferred (1 1 1) orientation. Using the CdTe thin film (3 × 5 cm{sup 2}) which is taken from the deposited large-area film, the 14.6% efficiency CdS/CdTe thin film solar cell has been prepared successfully. The structure of the cell is glass/FTO/CdS/CdTe/graphite slurry/Au, short circuit current density (J{sub sc}) of the cell is 26.9 mA/cm{sup 2}, open circuit voltage (V{sub oc}) is 823 mV, and filling factor (FF) is 66.05%. This technique can be a quite promising method to apply in the industrial production, as it has great prospects in the fabricating of large-area CdTe film.

  18. Advanced Processing of CdTe- and CuInxGa1-xSe2-Based Solar Cells: Final Report: 18 April 1995 - 31 May 1998

    International Nuclear Information System (INIS)

    Jayapalan, A.; Tetali, B.; Ferekides, C.S.; Marinskiy, D.; Morel, D.L.; Lin, H.; Sankaranarayanan, H.; Bhatt, R.; Narayanaswamy, R.; Prabhakaran, R.; Marinskaya, S.; Zafar, S.

    1999-01-01

    This report summarizes work performed by the University of South Florida Department of Electrical Engineering under this subcontract. The Cadmium telluride(CdTe) portion of this project deals with the development of high-efficiency thin-filmed CdTe solar cells using fabrication techniques that are suitable for manufacturing environments

  19. Improved electron density through hetero-junction binary sensitized TiO2/ CdTe / D719 system as photoanode for dye sensitized solar cell

    Science.gov (United States)

    Pandey, A. K.; Ahmad, Muhammad Shakeel; Alizadeh, Mahdi; Rahim, Nasrudin Abd

    2018-07-01

    The combined effect of dual sensitization and hetero-junction symmetry has been investigated on the performance of TiO2 based dye sensitized solar cell. CdTe nanoparticles have been introduced in TiO2 matrix to function as sensitizer as well as act as hetero-junction between D719 dye and TiO2 nanoarchitecture. Four concentrations of CdTe i.e. 0.5 wt%, 2 wt%, 5 wt% and 8 wt% have been investigated. Morphological and compositional studies have been conducted using scanning electron microscope (SEM) and X-ray diffraction (XRD) respectively. Light absorption characteristics have been investigated by employing Uv-vis spectroscopy and the overall performance has been studied using solar simulator and electrochemical impedance spectroscopy (EIS). Performance has been found to be increased with the addition of CdTe due to high electron density and reduction in recombination reactions. An increase of 41.73% in incident photo conversion efficiency (IPCE) and 75.57% in short circuit current density (Jsc) have been recorded for the specimens containing 5 wt% CdTe compared to bare TiO2 based DSSCs. Further addition of CdTe leads to reduction in overall performance of DSSCs.

  20. Enhancement of open-circuit voltage and the fill factor in CdTe nanocrystal solar cells by using interface materials

    International Nuclear Information System (INIS)

    Zhu, Jiaoyan; Yang, Yuehua; Gao, Yuping; Qin, Donghuan; Wu, Hongbin; Huang, Wenbo; Hou, Lintao

    2014-01-01

    Interface states influence the operation of nanocrystal (NC) solar cell carrier transport, recombination and energetic mechanisms. In a typical CdTe NC solar cell with a normal structure of a ITO/p-CdTe NCs/n-acceptor (or without)/Al configuration, the contact between the ITO and CdTe is a non-ohm contact due to a different work function (for an ITO, the value is ∼4.7 eV, while for CdTe NCs, the value is ∼5.3 eV), which results in an energetic barrier at the ITO/CdTe interface and decreases the performance of the NC solar cells. This work investigates how interface materials (including Au, MoO x and C 60 ) affect the performance of NC solar cells. It is found that devices with interface materials have shown higher V oc than those without interface materials. For the case in which we used Au as an interface, we obtained a high open-circuit voltage of 0.65 V, coupled with a high fill factor (62%); this resulted in a higher energy conversion efficiency (ECE) of 5.3%, which showed a 30% increase in the ECE compared with those without the interlayer. The capacitance measurements indicate that the increased V oc in the case in which Au was used as the interface is likely due to good ohm contact between the Au’s and the CdTe NCs’ thin film, which decreases the energetic barrier at the ITO/CdTe interface. (paper)

  1. Improvements in CdTe- and CIGS-based thin-film solar cells and investigation on new materials for photovoltaic applications.

    OpenAIRE

    Rosa, Greta

    2018-01-01

    Currently, thin-film solar cells are one of the most promising technologies for low-cost renewable energy production. CdTe- and CuInGaSe2-based cells, which achieved record efficiencies of 22.1% and 22.6% respectively, are the most attractive among thin-film solar cells. These high efficiencies have had a huge influence in making them highly competitive in the photovoltaic market, with an estimated final cost per module lower than US $ 0.50 per peak-watt. At the Thin Film Laboratory of the...

  2. Modification of electron states in CdTe absorber due to a buffer layer in CdTe/CdS solar cells

    International Nuclear Information System (INIS)

    Fedorenko, Y. G.; Major, J. D.; Pressman, A.; Phillips, L. J.; Durose, K.

    2015-01-01

    By application of the ac admittance spectroscopy method, the defect state energy distributions were determined in CdTe incorporated in thin film solar cell structures concluded on ZnO, ZnSe, and ZnS buffer layers. Together with the Mott-Schottky analysis, the results revealed a strong modification of the defect density of states and the concentration of the uncompensated acceptors as influenced by the choice of the buffer layer. In the solar cells formed on ZnSe and ZnS, the Fermi level and the energy position of the dominant deep trap levels were observed to shift closer to the midgap of CdTe, suggesting the mid-gap states may act as recombination centers and impact the open-circuit voltage and the fill factor of the solar cells. For the deeper states, the broadening parameter was observed to increase, indicating fluctuations of the charge on a microscopic scale. Such changes can be attributed to the grain-boundary strain and the modification of the charge trapped at the grain-boundary interface states in polycrystalline CdTe

  3. Modification of electron states in CdTe absorber due to a buffer layer in CdTe/CdS solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Fedorenko, Y. G., E-mail: y.fedorenko@liverpool.ac.uk; Major, J. D.; Pressman, A.; Phillips, L. J.; Durose, K. [Stephenson Institute for Renewable Energy and Department of Physics, School of Physical Sciences, Chadwick Building, University of Liverpool, Liverpool L69 7ZF (United Kingdom)

    2015-10-28

    By application of the ac admittance spectroscopy method, the defect state energy distributions were determined in CdTe incorporated in thin film solar cell structures concluded on ZnO, ZnSe, and ZnS buffer layers. Together with the Mott-Schottky analysis, the results revealed a strong modification of the defect density of states and the concentration of the uncompensated acceptors as influenced by the choice of the buffer layer. In the solar cells formed on ZnSe and ZnS, the Fermi level and the energy position of the dominant deep trap levels were observed to shift closer to the midgap of CdTe, suggesting the mid-gap states may act as recombination centers and impact the open-circuit voltage and the fill factor of the solar cells. For the deeper states, the broadening parameter was observed to increase, indicating fluctuations of the charge on a microscopic scale. Such changes can be attributed to the grain-boundary strain and the modification of the charge trapped at the grain-boundary interface states in polycrystalline CdTe.

  4. Development of MoO{sub x} thin films as back contact buffer for CdTe solar cells in substrate configuration

    Energy Technology Data Exchange (ETDEWEB)

    Gretener, C., E-mail: christina.gretener@empa.ch [Laboratory for Thin Films and Photovoltaics, Empa — Swiss Federal Laboratories for Materials Science and Technology, Überlandstr. 129, 8600 Dübendorf (Switzerland); Perrenoud, J.; Kranz, L.; Baechler, C. [Laboratory for Thin Films and Photovoltaics, Empa — Swiss Federal Laboratories for Materials Science and Technology, Überlandstr. 129, 8600 Dübendorf (Switzerland); Yoon, S. [Laboratory for Solid State Chemistry and Catalysis, Empa — Swiss Federal Laboratories for Materials Science and Technology, Überlandstr. 129, 8600 Dübendorf (Switzerland); Romanyuk, Y.E.; Buecheler, S.; Tiwari, A.N. [Laboratory for Thin Films and Photovoltaics, Empa — Swiss Federal Laboratories for Materials Science and Technology, Überlandstr. 129, 8600 Dübendorf (Switzerland)

    2013-05-01

    Molybdenum oxide compounds exhibit unique electrical and optical properties depending on oxygen vacancy concentration and composition and therefore, have recently attracted a lot of attention as a hole transport layer in various devices. In this work CdTe solar cells in substrate configuration were grown with evaporated MoO{sub x} back contact buffer layers and efficiencies of up to 10% could be achieved without using Cu in the back contact processing. The buffer layer – at the CdTe/back contact interface – in the finished cell was found to consist of MoO{sub 2} phase instead of the expected MoO{sub 3} phase as observed in as-deposited or annealed MoO{sub x} layers without CdTe deposition. In order to obtain MoO{sub x} buffer layers with desired stoichiometry, MoO{sub x} thin films were deposited by radio-frequency sputtering under different growth conditions. The chemical phase, composition, microstructure and optical properties of such layers were studied for their possible use in CdTe solar cells. - Highlights: ► MoO{sub x} is used as a back contact buffer in CdTe solar cells in substrate configuration. ► Efficiency of 10.0% was achieved without the addition of Cu. ► The back contact buffer in the finished device consists only of MoO{sub 2}. ► Phases and microstructure of MoO{sub x} can be controlled by sputtering conditions.

  5. Rational design of tetraphenylethylene-based luminescent down-shifting molecules: photophysical studies and photovoltaic applications in a CdTe solar cell from small to large units.

    Science.gov (United States)

    Li, Yilin; Li, Zhipeng; Ablekim, Tursunjan; Ren, Tianhui; Dong, Wen-Ji

    2014-12-21

    A rational design strategy of novel fluorophores for luminescent down-shifting (LDS) application was proposed and tested in this paper. Three new fluorophores (1a-c) with specific intramolecular charge transfer (ICT) and aggregation-induced emission (AIE) characteristics were synthesized as LDS molecules for increasing the output short circuit current density (Jsc) of a CdTe solar cell. Photophysical studies of their solution and solid states, and photovoltaic measurements of their PMMA solid films applied on a CdTe solar cell suggested that the specific spectroscopic properties and Jsc enhancement effects of these molecules were highly related to their chemical structures. The Jsc enhancement effects of these fluorophores were measured on both a CdTe small cell and a large panel. An increase in the output Jsc by as high as 5.69% for a small cell and 8.88% for a large panel was observed. Compared to a traditional LDS molecule, Y083, these fluorophores exhibited more superior capabilities of LDS.

  6. New Sunshine Program for fiscal 2000. Development of photovoltaic system commercialization technology - Development of thin-film solar cell manufacturing technology - Development of low-cost/large area module manufacturing technology (Development of high-reliability CdTe solar cell module manufacturing technology); 2000 nendo New sunshine keikaku seika hokokusho. Taiyoko hatsuden system jitsuyoka gijutsu kaihatsu, Hakumaku taiyodenchi no seizo gijutsu kaihatsu, Tei cost dai menseki mojuru seizo gijutsu kaihatsu (Koshinraisei CdTe taiyo denchi mojuru no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Research and development was conducted for reliable CdTe solar cell modules, large in area and high in efficiency. In the study of large-area CdS thin film fabrication, a conversion efficiency of 12.5-14.2% was achieved in a cell in a large-area substrate using a mist method-aided process of continuous CdS film fabrication. In the study of large-area CdTe thin film fabrication, the optimization was studied of the base-forming CdS film fabrication conditions and of the CdTe film fabrication conditions in a method using a CdTe powder processed by dry kneading, and a conversion efficiency peak was found to exist when the CdS film thickness was in the range of 700-900 angstrom. In the fabrication of large-area submodules, a large-area substrate was taken up, and TCO (transparent conducting oxide) film was fabricated by the mist method, CdTe film by the normal pressure CSS method, electrodes by the screen printing method, and CdTe film patterns by the blast method. As the result, a conversion efficiency of 11.0% was achieved. In a cost estimation for large-area CdTe solar cell modules, 140 yen/Wp (conversion efficiency: 11.0%, annual production: 100 MW) was obtained. (NEDO)

  7. Production of CdTe Semiconductor Thin Films by Electrodeposition Technique for Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Ahmet PEKSÖZ

    2016-08-01

    Full Text Available Electro-deposited cadmium tellurite (CuTe thin film was grown onto ITO-coated glass substrate for 120 seconds at the room temperature and a constant cathodic potential of -0.85 V. Deposition solution was prepared from cadmium chloride (CdCl2, sodium tellurite (Na2TeO3 and pure water. The pH value of the deposition solution was adjusted to 2.0 by adding HCl. The EDX analysis shows that the film has 52% Cd and 48% Te elemental compositions. Film thickness was found to be 140 nm. The CdTe thin film exhibits p-type semiconductor character, and has an energy bandgap of 1.47 eV. 

  8. Interface Study of ITO/ZnO and ITO/SnO2 Complex Transparent Conductive Layers and Their Effect on CdTe Solar Cells

    Directory of Open Access Journals (Sweden)

    Tingliang Liu

    2013-01-01

    Full Text Available Transparent ITO/ZnO and ITO/SnO2 complex conductive layers were prepared by DC- and RF-magnetron sputtering. Their structure and optical and electronic performances were studied by XRD, UV/Vis Spectroscopy, and four-probe technology. The interface characteristic and band offset of the ITO/ZnO, ITO/SnO2, and ITO/CdS were investigated by Ultraviolet Photoelectron Spectroscopy (UPS and X-ray Photoelectron Spectroscopy (XPS, and the energy band diagrams have also been determined. The results show that ITO/ZnO and ITO/SnO2 films have good optical and electrical properties. The energy barrier those at the interface of ITO/ZnO and ITO/SnO2 layers are almost 0.4 and 0.44 eV, which are lower than in ITO/CdS heterojunctions (0.9 eV, which is beneficial for the transfer and collection of electrons in CdTe solar cells and reduces the minority carrier recombination at the interface, compared to CdS/ITO. The effects of their use in CdTe solar cells were studied by AMPS-1D software simulation using experiment values obtained from ZnO, ITO, and SnO2. From the simulation, we confirmed the increase of Eff, FF, Voc, and Isc by the introduction of ITO/ZnO and ITO/SnO2 layers in CdTe solar cells.

  9. Preparation of p-type NiO films by reactive sputtering and their application to CdTe solar cells

    Science.gov (United States)

    Ishikawa, Ryousuke; Furuya, Yasuaki; Araki, Ryouichi; Nomoto, Takahiro; Ogawa, Yohei; Hosono, Aikyo; Okamoto, Tamotsu; Tsuboi, Nozomu

    2016-02-01

    Transparent p-type NiO films were prepared by reactive sputtering using the facing-target system under Ar-diluted O2 gas at Tsub of 30 and 200 °C. The increasing intensity of dominant X-ray diffraction (XRD) peaks indicates improvements in the crystallinity of NiO films upon Cu doping. In spite of the crystallographic and optical changes after Cu-doping, the electrical properties of Cu-doped NiO films were slightly improved. Upon Ag-doping at 30 °C under low O2 concentration, on the other hand, the intensity of the dominant (111) XRD peaks was suppressed and p-type conductivity increased from ˜10-3 to ˜10-1 S cm-1. Finally, our Ag-doped NiO films were applied as the back contact of CdTe solar cells. CdTe solar cells with a glass/ITO/CdS/CdTe/NiO structure exhibited an efficiency of 6.4%, suggesting the high potential of using p-type NiO for the back-contact film in thin-film solar cells.

  10. Effect of the grain sizes on the photovoltaic parameters of CdTe solar cells prepared by close space sublimation method

    International Nuclear Information System (INIS)

    Potlog, T.

    2007-01-01

    Thin Film CdS/CdTe solar cells were fabricated by Close Space Sublimation at the substrate temperature ranging from 300 degrees ± 5 degrees to 340 degrees ± degrees. The best photovoltaic parameters were achieved at substrate temperature 320 degrees and source temperature 610 degrees. The open circuit voltage and current density changes significantly with the substrate temperature and depends on the dimension of the grain sizes. Grain size is an efficiency limiting parameter for CdTe layers with large grains. The open circuit voltage and current density are the best for the cells having dimension of grains between 1.0 μm and ∼ 5.0 μm. CdS/CdTe solar cells with an efficiency of ∼ 10% were obtained. (author)

  11. Solution-processed efficient CdTe nanocrystal/CBD-CdS hetero-junction solar cells with ZnO interlayer

    International Nuclear Information System (INIS)

    Tian, Yiyao; Zhang, Yijie; Lin, Yizhao; Gao, Kuo; Zhang, Yunpeng; Liu, Kaiyi; Yang, Qianqian; Zhou, Xiao; Qin, Donghuan; Wu, Hongbin; Xia, Yuxin; Hou, Lintao; Lan, Linfeng; Chen, Junwu; Wang, Dan; Yao, Rihui

    2013-01-01

    CdTe nanocrystal (NC)/CdS p–n hetero-junction solar cells with an ITO/ZnO-In/CdS/CdTe/MoO x /Ag-inverted structure were prepared by using a layer-by-layer solution process. The CdS thin films were prepared by chemical bath deposition on top of ITO/ZnO-In and were found to be very compact and pin-hole free in a large area, which insured high quality CdTe NCs thin-film formation upon it. The device performance was strongly related to the CdCl 2 annealing temperature and annealing time. Devices exhibited power conversion efficiency (PCE) of 3.08 % following 400 °C CdCl 2 annealing for 5 min, which was a good efficiency for solution processed CdTe/CdS NC-inverted solar cells. By carefully designing and optimizing the CdCl 2 -annealing conditions (370 °C CdCl 2 annealing for about 15 min), the PCE of such devices showed a 21 % increase, in comparison to 400 °C CdCl 2 -annealing conditions, and reached a better PCE of 3.73 % while keeping a relatively high V OC of 0.49 V. This PCE value, to the best of our knowledge, is the highest PCE reported for solution processed CdTe–CdS NC solar cells. Moreover, the inverted solar cell device was very stable when kept under ambient conditions, less than 4 % degradation was observed in PCE after 40 days storage

  12. Solution-processed efficient CdTe nanocrystal/CBD-CdS hetero-junction solar cells with ZnO interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Yiyao; Zhang, Yijie; Lin, Yizhao; Gao, Kuo; Zhang, Yunpeng; Liu, Kaiyi; Yang, Qianqian [South China University of Technology, School of Materials Science and Engineering (China); Zhou, Xiao; Qin, Donghuan, E-mail: qindh@scut.edu.cn; Wu, Hongbin [South China University of Technology, Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices (China); Xia, Yuxin; Hou, Lintao [Jinan University, College of Science and Engineering (China); Lan, Linfeng; Chen, Junwu; Wang, Dan; Yao, Rihui [South China University of Technology, Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices (China)

    2013-11-15

    CdTe nanocrystal (NC)/CdS p–n hetero-junction solar cells with an ITO/ZnO-In/CdS/CdTe/MoO{sub x}/Ag-inverted structure were prepared by using a layer-by-layer solution process. The CdS thin films were prepared by chemical bath deposition on top of ITO/ZnO-In and were found to be very compact and pin-hole free in a large area, which insured high quality CdTe NCs thin-film formation upon it. The device performance was strongly related to the CdCl{sub 2} annealing temperature and annealing time. Devices exhibited power conversion efficiency (PCE) of 3.08 % following 400 °C CdCl{sub 2} annealing for 5 min, which was a good efficiency for solution processed CdTe/CdS NC-inverted solar cells. By carefully designing and optimizing the CdCl{sub 2}-annealing conditions (370 °C CdCl{sub 2} annealing for about 15 min), the PCE of such devices showed a 21 % increase, in comparison to 400 °C CdCl{sub 2}-annealing conditions, and reached a better PCE of 3.73 % while keeping a relatively high V{sub OC} of 0.49 V. This PCE value, to the best of our knowledge, is the highest PCE reported for solution processed CdTe–CdS NC solar cells. Moreover, the inverted solar cell device was very stable when kept under ambient conditions, less than 4 % degradation was observed in PCE after 40 days storage.

  13. Development of a computer model for polycrystalline thin-film CuInSe sub 2 and CdTe solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.L.; Schwartz, R.J.; Lee, Y.J. (Purdue Univ., Lafayette, IN (United States))

    1992-09-01

    This report describes work to develop an accurate numerical model for CuInSe{sub 2} (CIS) and CdTe-based solar cells capable of running on a personal computer. Such a model will aid researchers in designing and analyzing CIS- and CdTe-based solar cells. ADEPT (A Device Emulation Pregrain and Tool) was used as the basis for this model. An additional objective of this research was to use the models developed to analyze the performance of existing and proposed CIS- and CdTe-based solar cells. The development of accurate numerical models for CIS- and CdTe-based solar cells required the compilation of cell performance data (for use in model verification) and the compilation of measurements of material parameters. The development of the numerical models involved implementing the various physical models appropriate to CIS and CdTe, as well as some common window. A version of the model capable of running on an IBM-comparable personal computer was developed (primary code development is on a SUN workstation). A user-friendly interface with pop-up menus is continuing to be developed for release with the IBM-compatible model.

  14. FY 1999 research and development of technologies for commercialization of photovoltaic power generation systems. Development of technologies for production of thin-film solar cells and low-cost, large-area modules (Development of technologies for high-reliability CdTe solar cell modules); 1999 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu / tei cost daimenseki module seizo gijutsu kaihatsu (koshinraisei CdTe taiyo denchi module no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    The research and development project is implemented for production of low-cost, large-area modules of CdTe solar cells by the high-quality film-making process and high-function patterning, and the FY 1999 results are reported. The research program for the large-area TCO film-making technologies involves investigations on improvement of SnO{sub 2} film quality by the mist method and continuous film-making, which lead to continuous, stable production of 34 substrates of low resistance of 9.7{omega} on the average. The program for production of the large-area, thin-film CdS/CdTe solar cells involves production of TCO and CdS by the mist method, and patterning of the laminated TCO/CdS film by laser scribing. The CdTe film is formed by the atmospheric pressure CSS method, and treated with CdCl{sub 2} to improve its crystallinity. The CdTe film is patterned by sand blasting, and provided with the carbon and silver electrodes by screen printing, to complete the cell. The process is totally effected at the atmospheric pressure, needing no vacuum device. The CdTe solar cell assembly (130 cells connected in series, opening area: 5,413cm{sup 2}), fabricated on a trial basis, achieves a conversion efficiency of 10%. (NEDO)

  15. Solar cells based on electrodeposited thin films of ZnS, CdS, CdSSe and CdTe

    Science.gov (United States)

    Weerasinghe, Ajith R.

    The motivations of this research were to produce increased efficiency and low-cost solar cells. The production efficiency of Si solar cells has almost reached their theoretical limit, and reducing the manufacturing cost of Si solar cells is difficult to achieve due to the high-energy usage in material purifying and processing stages. Due to the low usage of materials and input energy, thin film solar cells have the potential to reduce the costs. CdS/CdTe thin film solar cells are already the cheapest on $/W basis. The cost of CdTe solar cells can be further reduced if all the semiconducting layers are fabricated using the electrodeposition (ED) method. ED method is scalable, low in the usage of energy and raw materials. These benefits lead to the cost effective production of semiconductors. The conventional method of fabricating CdS layers produces Cd containing waste solutions routinely, which adds to the cost of solar cells.ZnS, CdS and CdS(i-X)Sex buffer and window layers and CdTe absorber layers have been successfully electrodeposited and explored under this research investigation. These layers were fully characterised using complementary techniques to evaluate the material properties. Photoelectrochemical (PEC) studies, optical absorption, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, atomic force microscopy (AFM) and Raman spectroscopy were utilised to evaluate the material properties of these solid thin film layers. ZnS and CdS thin film layers were electrodeposited from Na-free chemical precursors to avoid the group I element (Na) to reduce deterioration of CdTe devices. Deposition parameters such as, growth substrates, temperature, pH, growth cathodic voltage, stirring rate, time and chemical concentrations were identified to fabricate the above semiconductors. To further optimise these layers, a heat treatment process specific to the material was developed. In addition

  16. Band Alignment for Rectification and Tunneling Effects in Al2O3 Atomic-Layer-Deposited on Back Contact for CdTe Solar Cell.

    Science.gov (United States)

    Su, Yantao; Xin, Chao; Feng, Yancong; Lin, Qinxian; Wang, Xinwei; Liang, Jun; Zheng, Jiaxin; Lin, Yuan; Pan, Feng

    2016-10-11

    The present work intends to explain why ultrathin Al 2 O 3 atomic-layer-deposited (ALD) on the back contact with rectification and tunneling effects can significantly improve the performance of CdTe solar cells in our previous work [ Liang , J. ; et al. Appl. Phys. Lett. 2015 , 107 , 013907 ]. Herein, we further study the mechanism through establishing the interfacial energy band diagram configuration of the ALD Al 2 O 3 /Cu x Te by experiment of X-ray photoelectron spectroscopy and first-principles calculations and conclude to find the band alignment with optimized layer thickness (about 1 nm ALD Al 2 O 3 ) as the key factor for rectification and tunneling effects.

  17. Cd-Te-In oxide thin films as possible transparent buffer layer in CdTe based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Castro-Rodriguez, R; Camacho, J M; Pena, J L [Applied Physics Department, CINVESTAV-IPN Merida, C.P. 97310, Merida, Yucatan (Mexico); Martel, A; Mendez-Gamboa, J, E-mail: romano@mda.cinvestav.m [Facultad de Ingenieria, Universidad Autonoma de Yucatan. AP 150 Cordemex, 97310 Merida, Yucatan (Mexico)

    2009-05-01

    Cd-Te-In-oxide thin films were grown by Pulsed Laser Deposition (PLD) technique using CdTe powder embedded in a matrix of indium metallic as target. The films were deposited at different oxygen pressures (P{sub o2}) from 15 to 50 mTorr at substrate temperature of 420{sup 0}C. Sheet resistance (R{sub sheet}) and transmission spectrum were measured as a function of P{sub o2}. From measurements of optical transmission, the Photonic Flux Density (PFD) spectrum were obtained and the integral of these PFD for each film were evaluated between energy range of 1.5 eV and 2.4 eV for obtain the amount of photons that can be transferred across the film in this range of solar energy spectrum. These values were evaluated over the R{sub sheet} to be used as a figure of merit. The best choice in our conditions was the films with P{sub o2} =28.5 mTorr, where the figure of merit reaches the maximum value.

  18. Study of the Mg incorporation in CdTe for developing wide band gap Cd1−xMgxTe thin films for possible use as top-cell absorber in a tandem solar cell

    International Nuclear Information System (INIS)

    Martínez, Omar S.; Millán, Aduljay Remolina; Huerta, L.; Santana, G.; Mathews, N.R.; Ramon-Garcia, M.L.; Morales, Erik R.; Mathew, X.

    2012-01-01

    Highlights: ► Thin films of Cd 1−x Mg x Te with high spatial uniformity and band gap in the range of 1.6–1.96 eV were deposited by vacuum co-evaporation of CdTe and Mg. ► Obtained Cd 1−x Mg x Te films have the structural characteristics of the CdTe, evidence of the change in atomic scattering due to incorporation of Mg was observed. ► XRD and XPS data confirmed the incorporation of Mg in the lattice of CdTe. ► SEM images revealed the impact of Mg incorporation on the morphology of the films, the changes in grain size and grain morphology are noticeable. - Abstract: Thin films of Cd 1−x Mg x Te with band gap in the range of 1.6–1.96 eV were deposited by vacuum co-evaporation of CdTe and Mg on glass substrates heated at 300 °C. Different experimental techniques such as XRD, UV–vis spectroscopy, SEM, and XPS were used to study the effect of Mg incorporation into the lattice of CdTe. The band gap of the films showed a clear tendency to increase as the Mg content in the film is increased. The Cd 1−x Mg x Te films maintain all the structural characteristics of the CdTe, however, diminishing of intensity for the XRD patterns is observed due to both change in preferential orientation and change in atomic scattering due to the incorporation of Mg. SEM images showed significant evidences of morphological changes due to the presence of Mg. XRD, UV–vis spectroscopy, and XPS data confirmed the incorporation of Mg in the lattice of CdTe. The significant increase in band gap of CdTe due to incorporation of Mg suggests that the Cd 1−x Mg x Te thin film is a candidate material to use as absorber layer in the top-cell of a tandem solar cell.

  19. Study of the Mg incorporation in CdTe for developing wide band gap Cd{sub 1-x}Mg{sub x}Te thin films for possible use as top-cell absorber in a tandem solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Omar S. [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, 62580 Temixco, Morelos (Mexico); Universidad Politecnica del Estado de Guerrero, Comunidad de Puente Campuzano, C.P. 40325 Taxco de Alarcon, Guerrero (Mexico); Millan, Aduljay Remolina [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, 62580 Temixco, Morelos (Mexico); Huerta, L.; Santana, G. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico. C.P 04510 Mexico D.F. (Mexico); Mathews, N.R.; Ramon-Garcia, M.L.; Morales, Erik R. [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, 62580 Temixco, Morelos (Mexico); Mathew, X., E-mail: xm@cie.unam.mx [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, 62580 Temixco, Morelos (Mexico)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Thin films of Cd{sub 1-x}Mg{sub x}Te with high spatial uniformity and band gap in the range of 1.6-1.96 eV were deposited by vacuum co-evaporation of CdTe and Mg. Black-Right-Pointing-Pointer Obtained Cd{sub 1-x}Mg{sub x}Te films have the structural characteristics of the CdTe, evidence of the change in atomic scattering due to incorporation of Mg was observed. Black-Right-Pointing-Pointer XRD and XPS data confirmed the incorporation of Mg in the lattice of CdTe. Black-Right-Pointing-Pointer SEM images revealed the impact of Mg incorporation on the morphology of the films, the changes in grain size and grain morphology are noticeable. - Abstract: Thin films of Cd{sub 1-x}Mg{sub x}Te with band gap in the range of 1.6-1.96 eV were deposited by vacuum co-evaporation of CdTe and Mg on glass substrates heated at 300 Degree-Sign C. Different experimental techniques such as XRD, UV-vis spectroscopy, SEM, and XPS were used to study the effect of Mg incorporation into the lattice of CdTe. The band gap of the films showed a clear tendency to increase as the Mg content in the film is increased. The Cd{sub 1-x}Mg{sub x}Te films maintain all the structural characteristics of the CdTe, however, diminishing of intensity for the XRD patterns is observed due to both change in preferential orientation and change in atomic scattering due to the incorporation of Mg. SEM images showed significant evidences of morphological changes due to the presence of Mg. XRD, UV-vis spectroscopy, and XPS data confirmed the incorporation of Mg in the lattice of CdTe. The significant increase in band gap of CdTe due to incorporation of Mg suggests that the Cd{sub 1-x}Mg{sub x}Te thin film is a candidate material to use as absorber layer in the top-cell of a tandem solar cell.

  20. Research on fabrication technology for thin film solar cells for practical use. Research on low-cost fabrication technology for large-area modules (CdS/CdTe solar cell modules); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Daimenseki module no tei cost seizo gijutsu (CdTe taiyo denchi module seizo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on the fabrication technology of CdS/CdTe solar cell modules in fiscal 1994. (1) On the fabrication technology for high-efficiency large-area solar cells, high-quality CdTe active layer was studied. S content taken in the active layer at sintering of CdTe decreased with an increase in formed CdTe, resulting in improvement of Voc of cells. (2) On the window layer with wide band gap, the solar cell superior in collection efficiency and photoelectric characteristics could be obtained using the newly developed mixed crystal film of Cd(1-x)Zn(x)S. (3) On the forming technology of large-area coating/sintering films, improvement of CdS film quality was studied by pressurized processing of printed CdS films. As a result, improvement of film density and light transmissivity was confirmed. (4) On the leveling process technology of CdTe films, smooth surface films were obtained by experiment using an equipment simultaneously exciting samples in all directions as one of uniform coating methods of films. 7 figs.

  1. Steady state minority carrier lifetime and defect level occupation in thin film CdTe solar cells

    International Nuclear Information System (INIS)

    Cheng, Zimeng; Delahoy, Alan E.; Su, Zhaoqian; Chin, Ken K.

    2014-01-01

    A model consisting of Shockley Read Hall (SRH) recombination under steady state conditions of constant photon injection is proposed in this work to study the steady state minority carrier lifetime in CdS/CdTe thin film solar cells. The SRH recombination rate versus optical injection level is analytically approximated in the junction and neutral regions. In the neutral region, it is found that the recombination rate through certain defect levels has one constant value under lower optical injection conditions and another constant value under higher optical injection conditions with the transition occurring at a critical optical injection level. By simultaneously solving the equations of charge neutrality, charge conservation and SRH recombination in the neutral region, it is found that the compensation of doping and the reduction of minority carrier lifetime by donors in the p-type semiconductor can each be remedied by optical injection. It is also demonstrated that this optical-dependent SRH recombination is significant in large bandgap thin films. The measured minority carrier diffusion length in a CdS/CdTe solar cells, as determined from the steady-state photo-generated carrier collection efficiency, shows the predicted transition of minority carrier lifetime versus optical injection level. A numerical fitting of the indirectly-measured minority carrier lifetime by assuming the minority carrier mobility gives a non-intuitive picture of the p–n junction with a low free hole concentration but a narrow depletion region width. - Highlights: • Minority carrier lifetimes under different optical injections are solved. • Simplifications of Shockley–Read–Hall recombination equation are discussed. • The compensation of donor can be remedied with optical injection. • The recombination efficiency of donor can be remedied with optical injection. • The minority carrier lifetime transition under illumination was experimentally observed

  2. Achievement report for fiscal 1997 on development of technologies for practical photovoltaic system under New Sunshine Program. Manufacture of thin-film solar cell and of low-cost/large-area module (Manufacture of high-reliability CdTe solar module); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu, tei cost daimenseki module seizo gijutsu kaihatsu (koshinraisei CdTe taiyo denchi module no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The target is a low-cost CdS/CdTe solar cell of a large area (60cm times 90cm), the establishment of mass-production technologies for the cell, and the enhancement of production efficiency. A thin film formation technology of subjecting CdS film organic metal to pyrolysis is established, which reduces photoabsorption loss in the shortwave domain of wavelength of not longer than 500nm, reduces reflection loss in the film, and improves on short-circuit current density. Improvement is also achieved on CdTe film quality and junction quality by use of a proximity sublimation method in a vacuum, when a conversion rate of 16.0% (1cm{sup 2}) is attained which is the highest in the world. Based on the results of the above-said efforts, a 3.3mm-thick glass substrate is employed for CdTe film to develop into a 30cm times 60cm-large size, with the film thereon uniformly thick over a large area thanks to a normal pressure proximity sublimation method. Studies are made toward a process nearer to the ultimate product and, using the patterning technique, a 30cm times 60cm-large CdTe solar cell is tentatively built realizing a conversion rate of 9.8%. (NEDO)

  3. How grain boundaries affect the efficiency of poly-CdTe solar-cells: A fundamental atomic-scale study of grain boundary dislocation cores using CdTe bi-crystal thin films.

    Energy Technology Data Exchange (ETDEWEB)

    Klie, Robert [Univ. of Illinois, Chicago, IL (United States)

    2016-10-25

    It is now widely accepted that grain boundaries in poly-crystalline CdTe thin film devices have a detrimental effect on the minority carrier lifetimes, the open circuit voltage and therefore the overall solar-cell performance. The goal of this project was to develop a fundamental understanding of the role of grain boundaries in CdTe on the carrier life-time, open-circuit voltage, Voc, and the diffusion of impurities. To achieve this goal, i) CdTe bi-crystals were fabricated with various misorientation angels, ii) the atomic- and electronic structures of the grain boundaries were characterized using scanning transmission electron microscopy (STEM), and iii) first-principles density functional theory modeling was performed on the structures determined by STEM to predict the grain boundary potential. The transport properties and minority carrier lifetimes of the bi-crystal grain boundaries were measured using a variety of approaches, including TRPL, and provided feedback to the characterization and modeling effort about the effectiveness of the proposed models.

  4. Solar-energy conversion by combined photovoltaic converters with CdTe and CuInSe2 base layers

    International Nuclear Information System (INIS)

    Khrypunov, G. S.; Sokol, E. I.; Yakimenko, Yu. I.; Meriuts, A. V.; Ivashuk, A. V.; Shelest, T. N.

    2014-01-01

    The possibility of the combined use of bifacial thin-film solar cells based on CdTe and frontal solar cells with a CuInSe 2 base layer in tandem structures is experimentally confirmed. It is found that, for the use of bifacial solar cells based on cadmium telluride in a tandem structure, the optimal thickness of their base layer should be 1 μm. The gain in the efficiency of the tandem structure, compared with an individual CuInSe 2 -based solar cell, is 1.8% in the case of series-connected solar cells and 1.3%, for parallel-connected

  5. Development of a computer model for polycrystalline thin-film CuInSe{sub 2} and CdTe solar cells. Final subcontract report, 1 January 1991--31 December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.L.; Schwartz, R.J.; Lee, Y.J. [Purdue Univ., Lafayette, IN (United States)

    1992-09-01

    This report describes work to develop an accurate numerical model for CuInSe{sub 2} (CIS) and CdTe-based solar cells capable of running on a personal computer. Such a model will aid researchers in designing and analyzing CIS- and CdTe-based solar cells. ADEPT (A Device Emulation Pregrain and Tool) was used as the basis for this model. An additional objective of this research was to use the models developed to analyze the performance of existing and proposed CIS- and CdTe-based solar cells. The development of accurate numerical models for CIS- and CdTe-based solar cells required the compilation of cell performance data (for use in model verification) and the compilation of measurements of material parameters. The development of the numerical models involved implementing the various physical models appropriate to CIS and CdTe, as well as some common window. A version of the model capable of running on an IBM-comparable personal computer was developed (primary code development is on a SUN workstation). A user-friendly interface with pop-up menus is continuing to be developed for release with the IBM-compatible model.

  6. Effects of Cd{sub 1-x}Zn{sub x}S alloy composition and post-deposition air anneal on ultra-thin CdTe solar cells produced by MOCVD

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, A.J., E-mail: Andrew.J.Clayton@Swansea.ac.uk [Centre for Solar Energy Research, College of Engineering, Swansea University, OpTIC, St. Asaph, LL17 0JD (United Kingdom); Baker, M.A.; Babar, S.; Grilli, R. [The Surface Analysis Laboratory, Department of Mechanical Engineering Sciences, University of Surrey, Guildford, GU2 7XH (United Kingdom); Gibson, P.N. [Institute for Health and Consumer Protection, Joint Research Centre of the European Commission, 21027, Ispra, VA (Italy); Kartopu, G.; Lamb, D.A. [Centre for Solar Energy Research, College of Engineering, Swansea University, OpTIC, St. Asaph, LL17 0JD (United Kingdom); Barrioz, V. [Engineering and Environment, Department of Physics and Electrical Engineering, Northumbria University, Newcastle, NE1 8ST (United Kingdom); Irvine, S.J.C. [Centre for Solar Energy Research, College of Engineering, Swansea University, OpTIC, St. Asaph, LL17 0JD (United Kingdom)

    2017-05-01

    Ultra-thin CdTe:As/Cd{sub 1-x}Zn{sub x}S photovoltaic solar cells with an absorber thickness of 0.5 μm were deposited by metal-organic chemical vapour deposition on indium tin oxide coated boro-aluminosilicate substrates. The Zn precursor concentration was varied to compensate for Zn leaching effects after CdCl{sub 2} activation treatment. Analysis of the solar cell composition and structure by X-ray photoelectron spectroscopy depth profiling and X-ray diffraction showed that higher concentrations of Zn in the Cd{sub 1-x}Zn{sub x}S window layer resulted in suppression of S diffusion across the CdTe/Cd{sub 1-x}Zn{sub x}S interface after CdCl{sub 2} activation treatment. Excessive Zn content in the Cd{sub 1-x}Zn{sub x}S alloy preserved the spectral response in the blue region of the solar spectrum, but increased series resistance for the solar cells. A modest increase in the Zn content of the Cd{sub 1-x}Zn{sub x}S alloy together with a post-deposition air anneal resulted in an improved blue response and an enhanced open circuit voltage and fill factor. This device yielded a mean efficiency of 8.3% over 8 cells (0.25 cm{sup 2} cell area) and best cell efficiency of 8.8%. - Highlights: • CdCl{sub 2} anneal treatment resulted in S diffusing to the back contact. • High Zn levels created mixed cubic/hexagonal structure at the p-n junction. • Increased Zn in Cd{sub 1-x}Zn{sub x}S supressed S diffusion into CdTe. • Device V{sub oc} was enhanced overall with an additional back surface air anneal.

  7. High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Final Technical Report, 4 March 1998--15 October 2001

    Energy Technology Data Exchange (ETDEWEB)

    Compaan, A. D.; Deng, X.; Bohn, R. G.

    2003-10-01

    This is the final report covering about 42 months of this subcontract for research on high-efficiency CdTe-based thin-film solar cells and on high-efficiency a-Si-based thin-film solar cells. Phases I and II have been extensively covered in two Annual Reports. For this Final Report, highlights of the first two Phases will be provided and then detail will be given on the last year and a half of Phase III. The effort on CdTe-based materials is led by Prof. Compaan and emphasizes the use of sputter deposition of the semiconductor layers in the fabrication of CdS/CdTe cells. The effort on high-efficiency a-Si materials is led by Prof. Deng and emphasizes plasma-enhanced chemical vapor deposition for cell fabrication with major efforts on triple-junction devices.

  8. Electrochemical Deposition of CdTe Semiconductor Thin Films for Solar Cell Application Using Two-Electrode and Three-Electrode Configurations: A Comparative Study

    Directory of Open Access Journals (Sweden)

    O. K. Echendu

    2016-01-01

    Full Text Available Thin films of CdTe semiconductor were electrochemically deposited using two-electrode and three-electrode configurations in potentiostatic mode for comparison. Cadmium sulphate and tellurium dioxide were used as cadmium and tellurium sources, respectively. The layers obtained using both configurations exhibit similar structural, optical, and electrical properties with no specific dependence on any particular electrode configuration used. These results indicate that electrochemical deposition (electrodeposition of CdTe and semiconductors in general can equally be carried out using two-electrode system as well as the conventional three-electrode system without compromising the essential qualities of the materials produced. The results also highlight the advantages of the two-electrode configuration in process simplification, cost reduction, and removal of a possible impurity source in the growth system, especially as the reference electrode ages.

  9. Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 1: a new theoretical procedure and comparison with other methodologies

    Science.gov (United States)

    Rangel-Kuoppa, Victor-Tapio; Albor-Aguilera, María-de-Lourdes; Hérnandez-Vásquez, César; Flores-Márquez, José-Manuel; González-Trujillo, Miguel-Ángel; Contreras-Puente, Gerardo-Silverio

    2018-04-01

    A new proposal for the extraction of the shunt resistance (R sh ) and saturation current (I sat ) of a current-voltage (I-V) measurement of a solar cell, within the one-diode model, is given. First, the Cheung method is extended to obtain the series resistance (R s ), the ideality factor (n) and an upper limit for I sat . In this article which is Part 1 of two parts, two procedures are proposed to obtain fitting values for R sh and I sat within some voltage range. These two procedures are used in two simulated I-V curves (one in darkness and the other one under illumination) to recover the known solar cell parameters R sh , R s , n, I sat and the light current I lig and test its accuracy. The method is compared with two different common parameter extraction methods. These three procedures are used and compared in Part 2 in the I-V curves of CdS-CdTe and CIGS-CdS solar cells.

  10. Leaching of cadmium and tellurium from cadmium telluride (CdTe) thin-film solar panels under simulated landfill conditions

    Science.gov (United States)

    Ramos-Ruiz, Adriana; Wilkening, Jean V.; Field, James A.; Sierra-Alvarez, Reyes

    2017-01-01

    A crushed non-encapsulated CdTe thin-film solar cell was subjected to two standardized batch leaching tests (i.e., Toxicity Characteristic Leaching Procedure (TCLP) and California Waste Extraction Test (WET)) and to a continuous-flow column test to assess cadmium (Cd) and tellurium (Te) dissolution under conditions simulating the acidic- and the methanogenic phases of municipal solid waste landfills. Low levels of Cd and Te were solubilized in both batch leaching tests (leaching behavior of CdTe in the columns is related to different aqueous pH and redox conditions promoted by the microbial communities in the columns, and is in agreement with thermodynamic predictions. PMID:28472709

  11. Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 2: application to experimental IV measurements and comparison with other methods

    Science.gov (United States)

    Rangel-Kuoppa, Victor-Tapio; Albor-Aguilera, María-de-Lourdes; Hérnandez-Vásquez, César; Flores-Márquez, José-Manuel; Jiménez-Olarte, Daniel; Sastré-Hernández, Jorge; González-Trujillo, Miguel-Ángel; Contreras-Puente, Gerardo-Silverio

    2018-04-01

    In this Part 2 of this series of articles, the procedure proposed in Part 1, namely a new parameter extraction technique of the shunt resistance (R sh ) and saturation current (I sat ) of a current-voltage (I-V) measurement of a solar cell, within the one-diode model, is applied to CdS-CdTe and CIGS-CdS solar cells. First, the Cheung method is used to obtain the series resistance (R s ) and the ideality factor n. Afterwards, procedures A and B proposed in Part 1 are used to obtain R sh and I sat . The procedure is compared with two other commonly used procedures. Better accuracy on the simulated I-V curves used with the parameters extracted by our method is obtained. Also, the integral percentage errors from the simulated I-V curves using the method proposed in this study are one order of magnitude smaller compared with the integral percentage errors using the other two methods.

  12. Fiscal 1998 New Sunshine Program achievement report. Development for practical application of photovoltaic system - Development of thin-film solar cell manufacturing technology (Development of low-cost/large-area module manufacturing technology - Development of high-reliability CdS/CdTe solar cell module manufacturing technology); 1998 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu / tei cost daimenseki module seizo gijutsu kaihatsu (koshinraisei CdTe taiyo denchi module no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Cost reduction for the above-named solar cells is the aim of this effort. On the basis of the results of past studies, a technology is established of fabricating a thin CdS film by subjecting a CdS film to organometal pyrolysis, and this brings about a decrease in photoabsorption loss in the range of waves shorter than 500nm and a decrease in in-film reflection loss for an increase in short-circuit current density. A proximity sublimation method is used for CdTe film fabrication, which improves on film quality and film adhesion. These efforts result in the achievement of a conversion efficiency of 16.0% which is the highest in the world. Studies are promoted in a process nearer to the ultimate form, and a 30cm times 60cm large CdTe solar cell is fabricated on the basis of a patterning technique, and the product attains a conversion efficiency of 9.8%. In fiscal 1998, studies center about the establishment of a film fabrication process for a medium-are substrate and about the enhancement of its conversion efficiency, and facilities capable of dealing with large-area substrates are introduced and operated. In a typical achievement, a CdTe solar cell is experimentally fabricated in a process which is wholly under normal pressure, and the product with an aperture area of 1376cm{sup 2} exhibits a conversion efficiency of 10.5% according to JQA (Japan Quality Assurance Organization). (NEDO)

  13. Silicon Solar Cell Efficiency Improvement Employing the Photoluminescent, Down-Shifting Effects of Carbon and CdTe Quantum Dots (Open Access Publisher’s Version)

    Science.gov (United States)

    2016-03-21

    Universidad de Guadalajara, Blvd. Gral. Marcelino Garcı́a Barragán 1421, Olı́mpica, 44430 Guadalajara, Jal., México 3 Departamento de Fı́sica... Universidad de Sonora, Hermosillo, Sonora, Mexico 123 Mater Renew Sustain Energy (2016) 5:5 DOI 10.1007/s40243-016-0070-4 of these nano structures, their...descendente basado en puntos cuánticos de telururo de cadmio aplicado a celdas solares de silicio cristalino. Dissertation, Universidad de

  14. Leaching of cadmium and tellurium from cadmium telluride (CdTe) thin-film solar panels under simulated landfill conditions.

    Science.gov (United States)

    Ramos-Ruiz, Adriana; Wilkening, Jean V; Field, James A; Sierra-Alvarez, Reyes

    2017-08-15

    A crushed non-encapsulated CdTe thin-film solar cell was subjected to two standardized batch leaching tests (i.e., Toxicity Characteristic Leaching Procedure (TCLP) and California Waste Extraction Test (WET)) and to a continuous-flow column test to assess cadmium (Cd) and tellurium (Te) dissolution under conditions simulating the acidic- and the methanogenic phases of municipal solid waste landfills. Low levels of Cd and Te were solubilized in both batch leaching tests (<8.2% and <3.6% of added Cd and Te, respectively). On the other hand, over the course of 30days, 73% of the Cd and 21% of the Te were released to the synthetic leachate of a continuous-flow column simulating the acidic landfill phase. The dissolved Cd concentration was 3.24-fold higher than the TCLP limit (1mgL -1 ), and 650-fold higher than the maximum contaminant level established by the US-EPA for this metal in drinking water (0.005mgL -1 ). In contrast, the release of Cd and Te to the effluent of the continuous-flow column simulating the methanogenic phase of a landfill was negligible. The remarkable difference in the leaching behavior of CdTe in the columns is related to different aqueous pH and redox conditions promoted by the microbial communities in the columns, and is in agreement with thermodynamic predictions. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Processing and Characterization of Thin Cadmium Telluride Solar Cells

    Science.gov (United States)

    Wojtowicz, Anna

    Cadmium telluride (CdTe) has the highest theoretical limit to conversion efficiency of single-junction photovoltaic (PV) technologies today. However, despite a maximum theoretical open-circuit voltage of 1.20 V, record devices have historically had voltages pinned around only 900 mV. Voltage losses due to high recombination rates remains to be the most complex hurdle to CdTe technology today, and the subject of on-going research in the physics PV group at Colorado State University. In this work, an ultrathin CdTe device architecture is proposed in an effort to reduce bulk recombination and boost voltages. By thinning the CdTe layer, a device's internal electric field extends fully towards the back contact. This quickly separates electrons-hole pairs throughout the bulk of the device and reduces overall recombination. Despite this advantage, very thin CdTe layers also present a unique set of optical and electrical challenges which result in performance losses not as prevalent in thicker devices. When fabricating CdTe solar cells, post-deposition treatments applied to the absorber layer are a critical step for achieving high efficiency devices. Exposure of the polycrystalline CdTe film to a chlorine species encourages the passivation of dangling bonds and larger grain formation, while copper-doping improves device uniformity and voltages. This work focuses on experiments conducted via close-space sublimation to optimize CdCl2 and CuCl treatments for thin CdTe solar cells. Sweeps of both exposure and anneal time were performed for both post-deposition treatments on CdTe devices with 1.0 mum absorber layers. The results demonstrate that thin CdTe devices require substantially less post-deposition processing than standard thicker devices as expected. Additionally, the effects of CdTe growth temperature on thin devices is briefly investigated. The results suggest that higher growth temperatures lead to both electrical and stoichiometric changes in CdTe closely associated

  16. Solar cells

    International Nuclear Information System (INIS)

    1980-01-01

    A method of producing solar cells is described which consists of producing a substantially monocrystalline tubular body of silicon or other suitable semiconductor material, treating this body to form an annular rectifying junction and then cutting it longitudinally to form a number of nearly flat ribbons from which the solar cells are fabricated. The P=N rectifying junction produced by the formation of silicon dioxide on the layers at the inner and outer surfaces of the body can be formed by ion-implantation or diffusion. (U.K.)

  17. Comparative Health Risk Assessment of CdTe Solar PV System and Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Sang Hun; Kang, Hyun Gook

    2014-01-01

    In terms of national energy policy decision-making process, several key factors, including low production cost, negligible risk or impact to environment and population around the facility, must be considered. The purpose of this paper is to assess the public health risk in case of postulated nuclear power plant and CdTe solar PV system accident and compare the estimated public health risk. Both systems release toxic materials to the environment which adversely affect nearby population by exposure from the inhalation and ingestion of the toxic material transported via air. By simulating the airborne transport of released toxic material using Gaussian plume model and modeling exposure pathways to nearby population, average individual health risk is assessed and public health risk per power capacity of each system is compared. The result shows that the average public health risk per power capacity of NPP is less than the case of solar PV system. This implies that NPP has lower risk in terms of public health risk in case of severe accident while it can be used as more reliable energy source than renewable energy source so that NPP would take priority over other renewable energy sources in terms of national energy policy

  18. Semi-transparent solar cells

    International Nuclear Information System (INIS)

    Sun, J; Jasieniak, J J

    2017-01-01

    Semi-transparent solar cells are a type of technology that combines the benefits of visible light transparency and light-to-electricity conversion. One of the biggest opportunities for such technologies is in their integration as windows and skylights within energy-sustainable buildings. Currently, such building integrated photovoltaics (BIPV) are dominated by crystalline silicon based modules; however, the opaque nature of silicon creates a unique opportunity for the adoption of emerging photovoltaic candidates that can be made truly semi-transparent. These include: amorphous silicon-, kesterite-, chalcopyrite-, CdTe-, dye-sensitized-, organic- and perovskite- based systems. For the most part, amorphous silicon has been the workhorse in the semi-transparent solar cell field owing to its established, low-temperature fabrication processes. Excitement around alternative classes, particularly perovskites and the inorganic candidates, has recently arisen because of the major efficiency gains exhibited by these technologies. Importantly, each of these presents unique opportunities and challenges within the context of BIPV. This topic review provides an overview into the broader benefits of semi-transparent solar cells as building-integrated features, as well as providing the current development status into all of the major types of semi-transparent solar cells technologies. (topical review)

  19. Semi-transparent solar cells

    Science.gov (United States)

    Sun, J.; Jasieniak, J. J.

    2017-03-01

    Semi-transparent solar cells are a type of technology that combines the benefits of visible light transparency and light-to-electricity conversion. One of the biggest opportunities for such technologies is in their integration as windows and skylights within energy-sustainable buildings. Currently, such building integrated photovoltaics (BIPV) are dominated by crystalline silicon based modules; however, the opaque nature of silicon creates a unique opportunity for the adoption of emerging photovoltaic candidates that can be made truly semi-transparent. These include: amorphous silicon-, kesterite-, chalcopyrite-, CdTe-, dye-sensitized-, organic- and perovskite- based systems. For the most part, amorphous silicon has been the workhorse in the semi-transparent solar cell field owing to its established, low-temperature fabrication processes. Excitement around alternative classes, particularly perovskites and the inorganic candidates, has recently arisen because of the major efficiency gains exhibited by these technologies. Importantly, each of these presents unique opportunities and challenges within the context of BIPV. This topic review provides an overview into the broader benefits of semi-transparent solar cells as building-integrated features, as well as providing the current development status into all of the major types of semi-transparent solar cells technologies.

  20. Solution-processing of ultra-thin CdTe/ZnO nanocrystal solar cells

    International Nuclear Information System (INIS)

    MacDonald, Brandon I.; Gengenbach, Thomas R.; Watkins, Scott E.; Mulvaney, Paul; Jasieniak, Jacek J.

    2014-01-01

    We have carried out a detailed study into how modifications of the physical, chemical and optical properties of solution-processed, nanocrystalline CdTe layers influence the photovoltaic performance of sintered CdTe/ZnO nanocrystal solar cells. Such solar cells are fabricated through layer-by-layer assembly, which is enabled through an inter layer chemical and thermal treatment cycle. In this manner we are able to fabricate working solar cells with sintered CdTe layers as low as 90 nm, provided that grain size is precisely controlled. We show that the extent of grain growth achieved during the CdTe sintering process is strongly dependent on nanocrystal surface chemistry and chemical environment, with the removal of the organic capping ligands and the introduction of CdCl 2 prior to annealing leading to greatly enhanced growth. Due to the air processing involved and the nanocrystalline nature of the CdTe, the overall performance of these solar cells is shown to be strongly dependent on both annealing temperature and time, with optimal results requiring a balance between crystal growth and degradation due to oxidation. Using this simple bi-layer device structure, optimized treatment conditions result in power conversion efficiencies of up to 7.7% and peak internal quantum efficiencies in excess of 95%. - Highlights: • We study the growth of nanocrystalline CdTe thin films from colloidal nanocrystals. • We examine the CdTe growth profiles as a function of surface chemistry. • We show that nanocrystalline CdTe is susceptible to oxidation under air annealing. • We show how this oxidation influences performance in CdTe/ZnO solar cells. • We demonstrate CdTe/ZnO solar cells with an efficiency of 7.7% fabricated in air

  1. CdTe quantum dots with daunorubicin induce apoptosis of multidrug-resistant human hepatoma HepG2/ADM cells: in vitro and in vivo evaluation

    Directory of Open Access Journals (Sweden)

    Shi Lixin

    2011-01-01

    Full Text Available Abstract Cadmium telluride quantum dots (Cdte QDs have received significant attention in biomedical research because of their potential in disease diagnosis and drug delivery. In this study, we have investigated the interaction mechanism and synergistic effect of 3-mercaptopropionic acid-capped Cdte QDs with the anti-cancer drug daunorubicin (DNR on the induction of apoptosis using drug-resistant human hepatoma HepG2/ADM cells. Electrochemical assay revealed that Cdte QDs readily facilitated the uptake of the DNR into HepG2/ADM cells. Apoptotic staining, DNA fragmentation, and flow cytometry analysis further demonstrated that compared with Cdte QDs or DNR treatment alone, the apoptosis rate increased after the treatment of Cdte QDs together with DNR in HepG2/ADM cells. We observed that Cdte QDs treatment could reduce the effect of P-glycoprotein while the treatment of Cdte QDs together with DNR can clearly activate apoptosis-related caspases protein expression in HepG2/ADM cells. Moreover, our in vivo study indicated that the treatment of Cdte QDs together with DNR effectively inhibited the human hepatoma HepG2/ADM nude mice tumor growth. The increased cell apoptosis rate was closely correlated with the enhanced inhibition of tumor growth in the studied animals. Thus, Cdte QDs combined with DNR may serve as a possible alternative for targeted therapeutic approaches for some cancer treatments.

  2. Elaboration of fabrication technology of ITO/CdS/CdTe solar cells on flexible polymer substrates

    International Nuclear Information System (INIS)

    Potlog, T.; Spalatu, N.; Capros, N.

    2007-01-01

    The development of high efficiency, stable, lightweight and flexible solar cell is important for terrestrial and space applications. We have developed a novel process to make solar cells on flexible polymer sheets. A thin layer of CdTe compound semiconductor is used for the absorption of solar light and generation of electrical current. In this work the solar electricity conversion efficiency of 4,66% is the highest efficiency reported for a solar cell grown on a polymer sheet. (authors)

  3. Investigation of the chlorine A-Center in polycrystalline CdTe layers by photoluminescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, Christian; Metzner, Heiner; Haedrich, Mathias [Institut fuer Festkoerperphysik, Universitaet Jena, Max-Wien-Platz 1, 07743 Jena (Germany); Schley, Pascal [Institut fuer Physik, Technische Universitaet Ilmenau, 98684 Ilmenau (Germany); Goldhahn, Ruediger [Institut fuer Experimentelle Physik, Universitaet Magdeburg, 39016 Magdeburg (Germany)

    2012-07-01

    Polycrystalline CdTe is a well known absorber material for thin film solar cells. However, the improvement of CdTe-based solar cells for industrial application is mainly based on empirical enhancements of certain process steps which are not concerning the absorber itself. Hence, the defect structure of CdTe is still not understood in detail. One of the most discussed defects in CdTe is the so called chlorine A-center. In general, the A-Center describes a defect complex of the intrinsic cadmium vacancy defect and an extrinsic impurity. By means of photoluminescence spectroscopy at temperatures of 5 K we investigated the behavior of the chlorine A-center under different CdTe activation techniques. Therefore, we were able to determine the electronic level of that defect and to analyze its influence on the crystal quality and the functionality of solar cells that were prepared of the corresponding samples.

  4. Thin film solar cell technology in Germany

    International Nuclear Information System (INIS)

    Diehl, W.; Sittinger, V.; Szyszka, B.

    2005-01-01

    Within the scope of limited nonrenewable energy resources and the limited capacity of the ecosystem for greenhouse gases and nuclear waste, sustainability is one important target in the future. Different energy scenarios showed the huge potential for photovoltaics (PV) to solve this energy problem. Nevertheless, in the last decade, PV had an average growth rate of over 20% per year. In 2002, the solar industry delivered more than 500 MWp/year of photovoltaic generators [A. Jaeger-Waldau, A European Roadmap for PV R and D, E-MRS Spring Meeting, (2003)]. More than 85% of the current production involves crystalline silicon technologies. These technologies still have a high cost reduction potential, but this will be limited by the silicon feedstock. On the other hand the so-called second generation thin film solar cells based on a-Si, Cu(In,Ga)(Se,S 2 (CIGS) or CdTe have material thicknesses of a few microns as a result of their direct band gap. Also, the possibility of circuit integration offers an additional cost reduction potential. Especially in Germany, there are a few companies who focus on thin film solar cells. Today, there are two manufacturers with production lines: the Phototronics (PST) division of RWE-Schott Solar with a-Si thin film technology and the former Antec Solar GmbH (now Antec Solar Energy GmbH) featuring the CdTe technology. A pilot line based on CIGS technology is run by Wuerth Solar GmbH. There is also a variety of research activity at other companies, namely, at Shell Solar, Sulfurcell Solartechnik GmbH, Solarion GmbH and the CIS-Solartechnik GmbH. We will give an overview on research activity on various thin film technologies, as well as different manufacturing and production processes in the companies mentioned above. (Author)

  5. Solar cells: An environment-benign energy source?

    International Nuclear Information System (INIS)

    Alsema, E.; Van Engelenburg, B.

    1993-01-01

    Attention is paid to a study on the environmental aspects of solar cell production techniques and the possibility of recycling solar cell materials. In the study the following types of solar cell modules are dealt with: CdTe and CuInSe 2 , amorphous silicon, crystalline silicon, and GaAs. It appears that silicon solar cells have minor environmental effects and are controllable. However, attention should be paid to the energy consumption and the use of etching and purification materials during the production of solar cells, and the emission of heavy metals from f.e. CdTe/CIS solar cells during and after usage. Without effective recycling enough supplies of indium, selenium and tellurium cannot be guaranteed. 3 figs., 1 ill

  6. Copper zinc tin sulfide-based thin film solar cells

    CERN Document Server

    Ito, Kentaro

    2014-01-01

    Beginning with an overview and historical background of Copper Zinc Tin Sulphide (CZTS) technology, subsequent chapters cover properties of CZTS thin films, different preparation methods of CZTS thin films, a comparative study of CZTS and CIGS solar cell, computational approach, and future applications of CZTS thin film solar modules to both ground-mount and rooftop installation. The semiconducting compound (CZTS) is made up earth-abundant, low-cost and non-toxic elements, which make it an ideal candidate to replace Cu(In,Ga)Se2 (CIGS) and CdTe solar cells which face material scarcity and tox

  7. CdTe QDs-based prostate-specific antigen probe for human prostate cancer cell imaging

    International Nuclear Information System (INIS)

    Dong Wei; Guo Li; Wang Meng; Xu Shukun

    2009-01-01

    L-glutathione (GSH) stabilized CdTe quantum dots (QDs) were directly prepared in aqueous solution. The as-prepared QDs were linked to prostate-specific antigen (PSA) for the direct labeling and linked to immunoglobulin G (IgG) for the indirect labeling of fixed prostate cancer cells. The results indicated that QD-based probes were ideal fluorescent markers with excellent spectral properties and photostability and much better than organic dyes making them very suitable in target detection. Meanwhile, the indirect labeling showed much better specificity than the direct labeling. Furthermore, the prepared CdTe QDs did not show detectable effect on cell growth after having cultured for three days, which suggested that the L-glutathione capped CdTe had scarcely cytotoxicity.

  8. Nanotetrapods: quantum dot hybrid for bulk heterojunction solar cells

    Science.gov (United States)

    2013-01-01

    Hybrid thin film solar cell based on all-inorganic nanoparticles is a new member in the family of photovoltaic devices. In this work, a novel and performance-efficient inorganic hybrid nanostructure with continuous charge transportation and collection channels is demonstrated by introducing CdTe nanotetropods (NTs) and CdSe quantum dots (QDs). Hybrid morphology is characterized, demonstrating an interpenetration and compacted contact of NTs and QDs. Electrical measurements show enhanced charge transfer at the hybrid bulk heterojunction interface of NTs and QDs after ligand exchange which accordingly improves the performance of solar cells. Photovoltaic and light response tests exhibit a combined optic-electric contribution from both CdTe NTs and CdSe QDs through a formation of interpercolation in morphology as well as a type II energy level distribution. The NT and QD hybrid bulk heterojunction is applicable and promising in other highly efficient photovoltaic materials such as PbS QDs. PMID:24139059

  9. Introduction to solar cell production

    International Nuclear Information System (INIS)

    Kim, Gyeong Hae; Lee, Jun Sin

    2009-08-01

    This book introduces solar cell production. It is made up eight chapters, which are summary of solar cell with structure and prospect of the business, special variable of solar cell on light of the sun and factor causing variable of solar cell, production of solar cell with surface texturing, diffusion, metal printing dry and firing and edge isolation, process of solar cell on silicone wafer for solar cell, forming of electrodes, introduction of thin film solar cell on operating of solar cell, process of production and high efficiency of thin film solar cell, sorting of solar cell and production with background of silicone solar cell and thin film solar cell, structure and production of thin film solar cell and compound solar cell, introduction of solar cell module and the Industrial condition and prospect of solar cell.

  10. Diffusion and influence of Cu on properties of CdTe thin films and CdTe/CdS cells

    Energy Technology Data Exchange (ETDEWEB)

    Dzhafarov, T.D.; Yesilkaya, S.S.; Yilmaz Canli, N.; Caliskan, M. [Department of Physics, Yildiz Technical University, Davutpasa, 34210 Istanbul (Turkey)

    2005-01-31

    The effective diffusion coefficients of Cu for thermal and photodiffusion in the CdTe films have been estimated from resistivity versus duration of thermal or photoannealing curves. In the temperature range 60-200{sup o}C the effective coefficient of thermal diffusion (D{sub t}) and photodiffusion (D{sub ph}) are described as D{sub t}=7.3x10{sup -7}exp(-0.33/kT) and D{sub ph}=4.7x10{sup -8}exp(-0.20/kT). It is found that the diffusion doping of CdTe thin films by Cu at 400{sup o}C results in a sharp decrease of resistivity up to 7 orders of magnitude of p-type material, depending on thickness of Cu film. The comparative study of performance of CdTe(Cu)/CdS and CdTe/CdS cells has been studied. It is shown that the diffusion doping of CdTe film by Cu increases efficiency of CdTe(Cu)/CdS cells from 0.9% to 6.8%. The degradation of photovoltaic parameters of CdTe(Cu)/CdS cell, during testing under forward and reverse bias at room temperature, proceeds at a larger rate than those of CdTe/CdS cell without Cu. The degradation of performance of CdTe(Cu)/CdS cells is tentatively assigned to electrodiffusion of Cu in CdTe, resulting in redistribution of concentration of Cu-related centers in CdTe film and heterojunction region.

  11. Photostimulated changes of properties of CdTe films

    Energy Technology Data Exchange (ETDEWEB)

    Dzhafarov, T.D. [Institute of Physics, Azerbaijan National Academy of Sciences, AZ-1143 Baku (Azerbaijan); Yesilkaya, S.S. [Department of Physics, Yildiz Technical University, 34210 Esenler/Istanbul (Turkey)

    2007-08-15

    The effect of illumination during the close-spaced sublimation (CSS) growth on composition, structural, electrical, optical and photovoltaic properties of CdTe films and CdTe/CdS solar cells were investigated. Data on comparative study by using X-ray diffraction (XRD), scanning electron microscopy (SEM), absorption spectra and conductivity-temperature measurements of CdTe films prepared by CSS method in dark (CSSD) and under illumination (CSSI) were presented. It is shown that the growth rate and the grain size of CdTe films grown under illumination is higher (by factor about of 1.5 and 3 respectively) than those for films prepared without illumination. The energy band gap of CdTe films fabricated by both technology, determined from absorption spectra, is same (about of 1.50 eV), however conductivity of the CdTe films produced by CSSI is considerably greater (by factor of 10{sup 7}) than that of films prepared by CSSD. The photovoltaic parameters of pCdTe/nCdS solar cells fabricated by photostimulated CSSI technology (J{sub sc}=28 mA/cm{sup 2}, V{sub oc}=0.63 V) are considerably larger than those for cells prepared by CSSD method (J{sub sc}=22 mA/cm{sup 2}, V{sub oc}=0.52 V). A mechanism of photostimulated changes of properties of CdTe films and improvement of photovoltaic parameters of CdTe/CdS solar cells is suggested. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  13. Solar Photovoltaic Cells.

    Science.gov (United States)

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  14. Photovoltaic properties of sintered CdS/CdTe solar cells doped with Cu

    International Nuclear Information System (INIS)

    Park, J.W.; Ahn, B.T.; Im, H.B.; Kim, C.S.

    1992-01-01

    In this paper, all polycrystalline CdS/CdTe solar cells doped with Cu are prepared by a screen printing and sintering method. Cell parameters of the sintered CdS/CdTe solar cells have been investigated in an attempt to find out the optimum doping conditions and concentrations of Cu by adding various amounts of CuCl 2 either into CdTe layer or into back contact carbon layer. Cell parameters of the sintered CdS/CdTe solar cells which contained various amounts of CuCl 2 in the CdTe layers before sintering stay at about the same values as the amount of CuCl 2 increases up to 25 ppm, and then decreases sharply as the amount of CuCl 2 further increases. The Cu added in the CdTe layer diffuses into the CdS layer during the sintering of the CdS-CdTe composite at 625 degrees C to densify the CdTe layer and causes the decrease in the optical transmission of CdS resulting in the degradation of the cell performance. In case the Cu dopant was dispersed in the back carbon paint and was followed by annealing, all cell parameters are improved significantly compared with those fabricated by adding CuCl 2 in the CdTe layer before sintering. A sintered CdS/CdTe solar cell which contained 25 ppm CuCl 2 in the carbon paste and was annealed at 350 degrees C for 10 min shows the highest efficiency. The efficiency of this cell is 12.4% under solar irradiation with an intensity of 80.4 mW/cm 2

  15. The role of oxygen in CdS/CdTe solar cells deposited by close-spaced sublimation

    Energy Technology Data Exchange (ETDEWEB)

    Rose, D.H.; Levi, D.H.; Matson, R.J. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    The presence of oxygen during close-spaced sublimation (CSS) of CdTe has been previously reported to be essential for high-efficiency CdS/CdTe solar cells because it increases the acceptor density in the absorber. The authors find that the presence of oxygen during CSS increases the nucleation site density of CdTe, thus decreasing pinhole density and grain size. Photoluminescence showed that oxygen decreases material quality in the bulk of the CdTe film, but positively impacts the critical CdS/CdTe interface. Through device characterization the authors were unable to verify an increase in acceptor density with increased oxygen. These results, along with the achievement of high-efficiency cells (13% AM1.5) without the use of oxygen, led the authors to conclude that the use of oxygen during CSS deposition of CdTe can be useful but is not essential.

  16. Caliste-SO, a CdTe based spectrometer for bright solar event observations in hard X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Meuris, A., E-mail: aline.meuris@cea.fr [CEA-Irfu – CEA Saclay, F-91191 Gif-sur-Yvette Cedex (France); Limousin, O.; Gevin, O.; Blondel, C.; Martignac, J. [CEA-Irfu – CEA Saclay, F-91191 Gif-sur-Yvette Cedex (France); Vassal, M.-C.; Soufflet, F.; Fiant, N. [3D Plus – 408 rue Hélène Boucher, F-78532 Buc Cedex (France); Bednarzik, M.; Stutz, S. [Paul Scherrer Institute (PSI), Laboratory for Micro- and Nanotechnology, 5232 Villigen (Switzerland); Grimm, O.; Commichau, V. [ETH Zurich, Institute for Particle Physics, Schafmattstrasse 20, 8093 Zurich (Switzerland)

    2015-07-01

    Caliste-SO is a CdTe hybrid detector designed to be used as a spectrometer for a hard X-ray Fourier telescope. The imaging technique was implemented in the Yohkoh satellite in 1991 and the RHESSI satellite in 2002 to achieve arc-second angular resolution images of solar flares with spectroscopic capabilities. The next generation of such instruments will be the Spectrometer Telescope Imaging X-rays (STIX) on-board the Solar Orbiter mission adopted by the European Space Agency in 2011 for launch in 2017. The design and performance of Caliste-SO allows both high spectral resolution and high count rate measurements from 4 to 150 keV with limited demands on spacecraft resources such as mass, power and volume (critical for interplanetary missions). The paper reports on the flight production of the Caliste-SO devices for STIX, describing the test facilities built-up in Switzerland and France. It illustrates some results obtained with the first production samples that will be mounted in the STIX engineering model.

  17. Solar cell concentrating system

    International Nuclear Information System (INIS)

    Garg, H.P.; Sharma, V.K.; Agarwal, R.K.

    1986-11-01

    This study reviews fabrication techniques and testing facilities for different solar cells under concentration which have been developed and tested. It is also aimed to examine solar energy concentrators which are prospective candidates for photovoltaic concentrator systems. This may provide an impetus to the scientists working in the area of solar cell technology

  18. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2015-09-08

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  19. ABC transporters affect the elimination and toxicity of CdTe quantum dots in liver and kidney cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Mingli; Yin, Huancai; Bai, Pengli [CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, Jiangsu 215163 (China); Miao, Peng [CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, Jiangsu 215163 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Deng, Xudong [Department of Chemical Engineering, McMaster University, Hamilton, Ontario, L8S 4L7 (Canada); Xu, Yingxue [CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, Jiangsu 215163 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Hu, Jun [CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, Jiangsu 215163 (China); Yin, Jian, E-mail: yinj@sibet.ac.cn [CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, Jiangsu 215163 (China)

    2016-07-15

    This paper aimed to investigate the role of adenosine triphosphate-binding cassette (ABC) transporters on the efflux and the toxicity of nanoparticles in liver and kidney cells. In this study, we synthesized CdTe quantum dots (QDs) that were monodispersed and emitted green fluorescence (maximum peak at 530 nm). Such QDs tended to accumulate in human hepatocellular carcinoma cells (HepG2), human kidney cells 2 (HK-2), and Madin-Darby canine kidney (MDCK) cells, and cause significant toxicity in all the three cell lines. Using specific inhibitors and inducers of P-glycoprotein (Pgp) and multidrug resistance associated proteins (Mrps), the cellular accumulation and subsequent toxicity of QDs in HepG2 and HK-2 cells were significantly affected, while only slight changes appeared in MDCK cells, corresponding well with the functional expressions of ABC transporters in cells. Moreover, treatment of QDs caused concentration- and time- dependent induction of ABC transporters in HepG2 and HK-2 cells, but such phenomenon was barely found in MDCK cells. Furthermore, the effects of CdTe QDs on ABC transporters were found to be greater than those of CdCl{sub 2} at equivalent concentrations of cadmium, indicating that the effects of QDs should be a combination of free Cd{sup 2+} and specific properties of QDs. Overall, these results indicated a strong dependence between the functional expressions of ABC transporters and the efflux of QDs, which could be an important reason for the modulation of QDs toxicity by ABC transporters. - Highlights: • ABC transporters contributed actively to the cellular efflux of CdTe quantum dots. • ABC transporters affected the cellular toxicity of CdTe quantum dots. • Treatment of CdTe quantum dots induced the gene expression of ABC transporters. • Free Cd{sup 2+} should be partially involved in the effects of QDs on ABC transporters. • Cellular efflux of quantum dots could be an important modulator for its toxicity.

  20. First principle analyses of direct bandgap solar cells with absorbing substrates versus mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, Alexander P. [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); Kirk, Wiley P. [Department of Materials Science and Engineering, University of Texas at Arlington, Arlington, Texas 76019 (United States)

    2013-11-07

    Direct bandgap InP, GaAs, CdTe, and Ga{sub 0.5}In{sub 0.5}P solar cells containing backside mirrors as well as parasitically absorbing substrates are analyzed for their limiting open circuit voltage and power conversion efficiency with comparison to record solar cells. From the principle of detailed balance, it is shown quantitatively that mirror solar cells have greater voltage and power conversion efficiency than their substrate counterparts. Next, the radiative recombination coefficient and maximum radiative lifetime of GaAs mirror and substrate solar cells are calculated and compared to the nonradiative Auger and Shockley-Read-Hall (SRH) lifetimes. Mirror solar cells have greater radiative lifetime than their substrate variants. Auger lifetime exceeds radiative lifetime for both substrate and mirror cells while SRH lifetime may be less or greater than radiative lifetime depending on trap concentration and capture cross section. Finally, the change in free energy of the photogenerated carriers is analyzed in a comparison between InP, GaAs, CdTe, and Ga{sub 0.5}In{sub 0.5}P mirror and substrate solar cells in order to characterize the relationship between solar photon quality and free energy management in solar cells with differing bandgaps. Wider bandgap visible threshold Ga{sub 0.5}In{sub 0.5}P solar cells make better use of the available change in free energy of the photogenerated charge carriers, even when normalized to the bandgap energy, than narrower bandgap near-IR threshold InP, GaAs, and CdTe solar cells.

  1. Rectenna solar cells

    CERN Document Server

    Moddel, Garret

    2013-01-01

    Rectenna Solar Cells discusses antenna-coupled diode solar cells, an emerging technology that has the potential to provide ultra-high efficiency, low-cost solar energy conversion. This book will provide an overview of solar rectennas, and provide thorough descriptions of the two main components: the diode, and the optical antenna. The editors discuss the science, design, modeling, and manufacturing of the antennas coupled with the diodes. The book will provide concepts to understanding the challenges, fabrication technologies, and materials required to develop rectenna structures. Written by e

  2. Fabrication of CdS/CdTe-Based Thin Film Solar Cells Using an Electrochemical Technique

    Directory of Open Access Journals (Sweden)

    I. M. Dharmadasa

    2014-06-01

    Full Text Available Thin film solar cells based on cadmium telluride (CdTe are complex devices which have great potential for achieving high conversion efficiencies. Lack of understanding in materials issues and device physics slows down the rapid progress of these devices. This paper combines relevant results from the literature with new results from a research programme based on electro-plated CdS and CdTe. A wide range of analytical techniques was used to investigate the materials and device structures. It has been experimentally found that n-, i- and p-type CdTe can be grown easily by electroplating. These material layers consist of nano- and micro-rod type or columnar type grains, growing normal to the substrate. Stoichiometric materials exhibit the highest crystallinity and resistivity, and layers grown closer to these conditions show n → p or p → n conversion upon heat treatment. The general trend of CdCl2 treatment is to gradually change the CdTe material’s n-type electrical property towards i-type or p-type conduction. This work also identifies a rapid structural transition of CdTe layer at 385 ± 5 °C and a slow structural transition at higher temperatures when annealed or grown at high temperature. The second transition occurs after 430 °C and requires more work to understand this gradual transition. This work also identifies the existence of two different solar cell configurations for CdS/CdTe which creates a complex situation. Finally, the paper presents the way forward with next generation CdTe-based solar cells utilising low-cost materials in their columnar nature in graded bandgap structures. These devices could absorb UV, visible and IR radiation from the solar spectrum and combine impact ionisation and impurity photovoltaic (PV effect as well as making use of IR photons from the surroundings when fully optimised.

  3. Quantum dot solar cells

    CERN Document Server

    Wu, Jiang

    2013-01-01

    The third generation of solar cells includes those based on semiconductor quantum dots. This sophisticated technology applies nanotechnology and quantum mechanics theory to enhance the performance of ordinary solar cells. Although a practical application of quantum dot solar cells has yet to be achieved, a large number of theoretical calculations and experimental studies have confirmed the potential for meeting the requirement for ultra-high conversion efficiency. In this book, high-profile scientists have contributed tutorial chapters that outline the methods used in and the results of variou

  4. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  5. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  6. Preparation and characterization of pulsed laser deposited CdTe thin films at higher FTO substrate temperature and in Ar + O{sub 2} atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Chao; Ming, Zhenxun [College of Materials Science and Engineering, Sichuan University, Chengdu 610064, Sichuan (China); Li, Bing, E-mail: libing70@126.com [College of Materials Science and Engineering, Sichuan University, Chengdu 610064, Sichuan (China); Feng, Lianghuan [College of Materials Science and Engineering, Sichuan University, Chengdu 610064, Sichuan (China); Wu, Judy [Department of Physics and Astronomy, Kansas University, Lawrence 66045 (United States)

    2013-06-20

    Highlights: • CdTe films were deposited by PLD at high substrate temperatures (400 °C, 550 °C). • CdTe films were achieved under the atmosphere (1.2 Torr) of Ar mixed with O{sub 2}. • Deposited CdTe films were cubic phase and had strong (1 0 0) preferred orientation. • Scanning electron microscope (SEM) showed an average grain size of 0.3–0.6 μm. • The ultra-thin film (CdS/PLD-CdTe) solar cell with efficiency of 6.68% was made. -- Abstract: Pulsed laser deposition (PLD) is one of the promising techniques for depositing cadmium telluride (CdTe) thin films. It has been reported that PLD CdTe thin films were almost deposited at the lower substrate temperatures (<300 °C) under vacuum conditions. However, the poor crystallinity of CdTe films prepared in this way renders them not conducive to the preparation of high-efficiency CdTe solar cells. To obtain high-efficiency solar cell devices, better crystallinity and more suitable grain size are needed, which requires the CdTe layer to be deposited by PLD at high substrate temperatures (>400 °C). In this paper, CdTe layers were deposited by PLD (KrF, λ = 248 nm, 10 Hz) at different higher substrate temperatures (T{sub s}). Excellent performance of CdTe films was achieved at higher substrate temperatures (400 °C, 550 °C) under an atmosphere of Ar mixed with O{sub 2} (1.2 Torr). X-ray diffraction analysis confirmed the formation of CdTe cubic phase with a strong (1 0 0) preferential orientation at all substrates temperatures on 60 mJ laser energy. The optical properties of CdTe were investigated, and the band gaps of CdTe films were 1.51 eV and 1.49 eV at substrate temperatures of 400 °C and 550 °C, respectively. Scanning electron microscopy (SEM) showed an average grain size of 0.3–0.6 μm. Thus, under these conditions of the atmosphere of Ar + O{sub 2} (15 Torr) and at the relatively high T{sub s} (500 °C), an thin-film (FTO/PLD-CdS (100 nm)/PLD-CdTe (∼1.5 μm)/HgTe: Cu/Ag) solar cell with an

  7. Methodological comparison on hybrid nano organic solar cell fabrication

    Science.gov (United States)

    Vairavan, Rajendaran; Hambali, Nor Azura Malini Ahmad; Wahid, Mohamad Halim Abd; Retnasamy, Vithyacharan; Shahimin, Mukhzeer Mohamad

    2018-02-01

    The development of low cost solar cells has been the main focus in recent years. This has lead to the generation of photovoltaic cells based on hybrid of nanoparticle-organic polymer materials. This type of hybrid photovoltaic cells can overcome the problem of polymeric devices having low optical absorption and carrier mobilities. The hybrid cell has the potential of bridging the efficiency gap, which in present in organic and inorganic semiconductor materials. This project focuses on obtaining an hybrid active layer consisting of nanoparticles and organic polymer, to understand the parameter involved in obtaining this active layer and finally to investigate if the addition of nano particles in to the active layer could enhance the output of the hybrid solar cell. The hybrid active layer have will be deposited using the spin coating technique by using CdTe, CdS nano particles mixed with poly (2-methoxy,5-(2-ethyl-hexyloxy)-p-phenylvinylene)MEH-PPV.

  8. Polymer tandem solar cells

    NARCIS (Netherlands)

    Gilot, J.

    2010-01-01

    Solar cells convert solar energy directly into electricity and are attractive contribute to the increasing energy demand of modern society. Commercial mono-crystalline silicon based devices are infiltrating the energy market but their expensive, time and energy consuming production process

  9. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  10. Conjugated Polymer Solar Cells

    National Research Council Canada - National Science Library

    Paraschuk, Dmitry Y

    2006-01-01

    This report results from a contract tasking Moscow State University as follows: Conjugated polymers are promising materials for many photonics applications, in particular, for photovoltaic and solar cell devices...

  11. Recent advances in sensitized mesoscopic solar cells.

    Science.gov (United States)

    Grätzel, Michael

    2009-11-17

    -intensive high vacuum and materials purification steps that are currently employed in the fabrication of all other thin-film solar cells. Organic materials are abundantly available, so that the technology can be scaled up to the terawatt scale without running into feedstock supply problems. This gives organic-based solar cells an advantage over the two major competing thin-film photovoltaic devices, i.e., CdTe and CuIn(As)Se, which use highly toxic materials of low natural abundance. However, a drawback of the current embodiment of OPV cells is that their efficiency is significantly lower than that for single and multicrystalline silicon as well as CdTe and CuIn(As)Se cells. Also, polymer-based OPV cells are very sensitive to water and oxygen and, hence, need to be carefully sealed to avoid rapid degradation. The research discussed within the framework of this Account aims at identifying and providing solutions to the efficiency problems that the OPV field is still facing. The discussion focuses on mesoscopic solar cells, in particular, dye-sensitized solar cells (DSCs), which have been developed in our laboratory and remain the focus of our investigations. The efficiency problem is being tackled using molecular science and nanotechnology. The sensitizer constitutes the heart of the DSC, using sunlight to pump electrons from a lower to a higher energy level, generating in this fashion an electric potential difference, which can exploited to produce electric work. Currently, there is a quest for sensitizers that achieve effective harnessing of the red and near-IR part of sunlight, converting these photons to electricity better than the currently used generation of dyes. Progress in this area has been significant over the past few years, resulting in a boost in the conversion efficiency of the DSC that will be reviewed.

  12. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  13. Iron sulphide solar cells

    Science.gov (United States)

    Ennaoui, A.; Tributsch, H.

    1984-12-01

    The abundant, naturally occurring natural compound pyrite (FeS2) can be used as a semiconducting material for photoelectrochemical and photovoltaic solar cells. Unlike most of the intensively studied photoactive materials, pyrite solar cell production would never be limited by the availability of the elements or by their compatibility with the environment. An energy gap of 0.95 eV has been determined for pyrite, and it is noted that the theoretical efficiency limit for solar energy conversion in this material is of the order of 15-20 percent.

  14. The effects of anode material type on the optoelectronic properties of electroplated CdTe thin films and the implications for photovoltaic application

    Science.gov (United States)

    Echendu, O. K.; Dejene, B. F.; Dharmadasa, I. M.

    2018-03-01

    The effects of the type of anode material on the properties of electrodeposited CdTe thin films for photovoltaic application have been studied. Cathodic electrodeposition of two sets of CdTe thin films on glass/fluorine-doped tin oxide (FTO) was carried out in two-electrode configuration using graphite and platinum anodes. Optical absorption spectra of films grown with graphite anode displayed significant spread across the deposition potentials compared to those grown with platinum anode. Photoelectrochemical cell result shows that the CdTe grown with graphite anode became p-type after post-deposition annealing with prior CdCl2 treatment, as a result of carbon incorporation into the films, while those grown with platinum anode remained n-type after annealing. A review of recent photoluminescence characterization of some of these CdTe films reveals the persistence of a defect level at (0.97-0.99) eV below the conduction band in the bandgap of CdTe grown with graphite anode after annealing while films grown with platinum anode showed the absence of this defect level. This confirms the impact of carbon incorporation into CdTe. Solar cell made with CdTe grown with platinum anode produced better conversion efficiency compared to that made with CdTe grown using graphite anode, underlining the impact of anode type in electrodeposition.

  15. Four-cell solar tracker

    Science.gov (United States)

    Berdahl, C. M.

    1981-01-01

    Forty cm Sun tracker, consisting of optical telescope and four solar cells, stays pointed at Sun throughout day for maximum energy collection. Each solar cell generates voltage proportional to part of solar image it receives; voltages drive servomotors that keep image centered. Mirrored portion of cylinder extends acquisition angle of device by reflecting Sun image back onto solar cells.

  16. Quantum dot solar cell

    International Nuclear Information System (INIS)

    Ahamefula, U.C.; Sulaiman, M.Y.; Sopian, K.; Ibarahim, Z.; Ibrahim, N.; Alghoul, M.A.; Haw, L.C.; Yahya, M.; Amin, N.; Mat, S.; Ruslan, M.H.

    2009-01-01

    Full text: The much awaited desire of replacing fossil fuel with photovoltaic will remain a fairy tale if the myriad of issues facing solar cell development are marginalized. Foremost in the list is the issue of cost. Silicon has reached a stage where its use on large scale can no longer be lavishly depended upon. The demand for high grade silicon from the microelectronics and solar industries has soared leading to scarcity. New approach has to be sought. Notable is the increased attention on thin films such as cadmium telluride, copper indium gallium diselenide, amorphous silicon, and the not so thin non-crystalline family of silicon. While efforts to address the issues of stability, toxicity and efficiency of these systems are ongoing, another novel approach is quietly making its appearance - quantum dots. Quantum dots seem to be promising candidates for solar cells because of the opportunity to manipulate their energy levels allowing absorption of a wider solar spectrum. Utilization of minute quantity of these nano structures is enough to bring the cost of solar cell down and to ascertain sustainable supply of useful material. The paper outlines the progress that has been made on quantum dot solar cells. (author)

  17. On the doping problem of CdTe films: The bismuth case

    Energy Technology Data Exchange (ETDEWEB)

    Vigil-Galan, O. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico); Brown, M. [Department of Physics and Astronomy, The University of Toledo, 43606 Toledo, OH (United States); Ruiz, C.M. [Depto. Fisica de Materiales, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Vidal-Borbolla, M.A. [Instituto de Investigacion en Comunicacion Optica, Av. Karakorum 1470, Lomas 4a. Secc., 78210 San Luis Potosi, SLP (Mexico); Ramirez-Bon, R. [CINVESTAV-IPN, U. Queretaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, 76230 Santiago de Queretaro, Qro. (Mexico); Sanchez-Meza, E. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico); Tufino-Velazquez, M. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico)], E-mail: mtufinovel@yahoo.com.mx; Calixto, M. Estela [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico); Compaan, A.D. [Department of Physics and Astronomy, The University of Toledo, 43606 Toledo, OH (United States); Contreras-Puente, G. [Escuela Superior de Fisica y Matematicas del IPN, Edif. 9, UPALM, 07738 Mexico, D. F. (Mexico)

    2008-08-30

    The controlled increase of hole concentration is an important issue and still an unsolved problem for polycrystalline CdTe-based solar cells. The typical hole concentration of as-grown CdTe thin-films goes up to 10{sup 13} cm{sup -3}, depending on the specific growth technique. The highest electron concentration obtained for CdS, the suitable window partner material of CdTe, is around 10{sup 15} cm{sup -3}. Thus, the PV-performance of a CdS/CdTe device can be optimized if the hole concentration in CdTe is increased. We have faced up this problem by studying the electrical properties of two types of CdTe films: CdTe films grown by Close Space Vapor Transport using a CdTe:Bi powder as the starting material and CdTe sputtered films doped by implantation with different Bi-doses. Temperature-dependent resistivity and Hall effect measurements and a discussion on the efficiency of both doping processes are presented.

  18. On the doping problem of CdTe films: The bismuth case

    International Nuclear Information System (INIS)

    Vigil-Galan, O.; Brown, M.; Ruiz, C.M.; Vidal-Borbolla, M.A.; Ramirez-Bon, R.; Sanchez-Meza, E.; Tufino-Velazquez, M.; Calixto, M. Estela; Compaan, A.D.; Contreras-Puente, G.

    2008-01-01

    The controlled increase of hole concentration is an important issue and still an unsolved problem for polycrystalline CdTe-based solar cells. The typical hole concentration of as-grown CdTe thin-films goes up to 10 13 cm -3 , depending on the specific growth technique. The highest electron concentration obtained for CdS, the suitable window partner material of CdTe, is around 10 15 cm -3 . Thus, the PV-performance of a CdS/CdTe device can be optimized if the hole concentration in CdTe is increased. We have faced up this problem by studying the electrical properties of two types of CdTe films: CdTe films grown by Close Space Vapor Transport using a CdTe:Bi powder as the starting material and CdTe sputtered films doped by implantation with different Bi-doses. Temperature-dependent resistivity and Hall effect measurements and a discussion on the efficiency of both doping processes are presented

  19. Perovskite Solar Cell

    Indian Academy of Sciences (India)

    Organic–inorganic halide perovskite, a newcomerin the solar cell industry has proved its potential forincreasing efficiency rapidly from 3.8% in 2009 to 22.1% in2016. High efficiency, flexibility, and cell architecture of theemerging hybrid halide perovskite have caught the attentionof researchers and technologists in the field.

  20. Efficiency enhancement calculations of state-of-the-art solar cells by luminescent layers with spectral shifting, quantum cutting, and quantum tripling function

    NARCIS (Netherlands)

    Ten Kate, O.M.; De Jong, M.; Hintzen, H.T.; Van der Kolk, E.

    2013-01-01

    Solar cells of which the efficiency is not limited by the Shockley-Queisser limit can be obtained by integrating a luminescent spectral conversion layer into the cell structure. We have calculated the maximum efficiency of state-of-the-art c-Si, pc-Si, a-Si, CdTe, GaAs, CIS, CIGS, CGS, GaSb, and Ge

  1. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Electrical and Communications Engineering

    1998-10-01

    Photovoltaic research in the Electron Physics Laboratory started in 1993, when laboratory joined the national TEKES/NEMO 2 research program. Since the beginning of the project, characterization as well as experimentally orientated development of the fabrication process of the solar cells were carried out parallery. The process development research started by the initiatives of the Finnish industry. At the moment a large amount of the laboratory personnel works on solar cell research and the financing comes mainly from external projects. The funding for the research has come from TEKES, Ministry of Education, Finnish Academy, GETA graduate school, special equipment grants of the university, and from the laboratory

  2. Flexible Solar Cells

    Science.gov (United States)

    1994-01-01

    Solar cell "modules" are plastic strips coated with thin films of photovoltaic silicon that collect solar energy for instant conversion into electricity. Lasers divide the thin film coating into smaller cells to build up voltage. Developed by Iowa Thin Film Technologies under NASA and DOE grants, the modules are used as electrical supply for advertising displays, battery rechargers for recreational vehicles, and to power model airplanes. The company is planning other applications both in consumer goods and as a power source in underdeveloped countries.

  3. Study of CdTe/CdS solar cell at low power density for low-illumination applications

    Energy Technology Data Exchange (ETDEWEB)

    Devi, Nisha, E-mail: nishatanwer1989@gmail.com; Aziz, Anver, E-mail: aaziz@jmi.ac.in [Department Of Physics, Solar PV Lab, Jamia Millia Islamia, New Delhi-110025 (India); Datta, Shouvik [Department of Physics, IISER-Pune, Dr.homi Bhabha road, Pashan, Pune-411008 (India)

    2016-05-06

    In this paper, we numerically investigate CdTe/CdS PV cell properties using a simulation program Solar Cell Capacitance Simulator in 1D (SCAPS-1D). A simple structure of CdTe PV cell has been optimized to study the effect of temperature, absorber thickness and work function at very low incident power. Objective of this research paper is to build an efficient and cost effective solar cell for portable electronic devices such as portable computers and cell phones that work at low incident power because most of such devices work at diffused and reflected sunlight. In this report, we simulated a simple CdTe PV cell at very low incident power, which gives good efficiency.

  4. Study of CdTe/CdS solar cell at low power density for low-illumination applications

    International Nuclear Information System (INIS)

    Devi, Nisha; Aziz, Anver; Datta, Shouvik

    2016-01-01

    In this paper, we numerically investigate CdTe/CdS PV cell properties using a simulation program Solar Cell Capacitance Simulator in 1D (SCAPS-1D). A simple structure of CdTe PV cell has been optimized to study the effect of temperature, absorber thickness and work function at very low incident power. Objective of this research paper is to build an efficient and cost effective solar cell for portable electronic devices such as portable computers and cell phones that work at low incident power because most of such devices work at diffused and reflected sunlight. In this report, we simulated a simple CdTe PV cell at very low incident power, which gives good efficiency.

  5. Flexible silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Blakers, A.W.; Armour, T. [Centre for Sustainable Energy Systems, The Australian National University, Canberra ACT 0200 (Australia)

    2009-08-15

    In order to be useful for certain niche applications, crystalline silicon solar cells must be able to sustain either one-time flexure or multiple non-critical flexures without significant loss of strength or efficiency. This paper describes experimental characterisation of the behaviour of thin crystalline silicon solar cells, under either static or repeated flexure, by flexing samples and recording any resulting changes in performance. Thin SLIVER cells were used for the experiment. Mechanical strength was found to be unaffected after 100,000 flexures. Solar conversion efficiency remained at greater than 95% of the initial value after 100,000 flexures. Prolonged one-time flexure close to, but not below, the fracture radius resulted in no significant change of properties. For every sample, fracture occurred either on the first flexure to a given radius of curvature, or not at all when using that radius. In summary, for a given radius of curvature, either the flexed solar cells broke immediately, or they were essentially unaffected by prolonged or multiple flexing. (author)

  6. Flexible Solar Cells

    NARCIS (Netherlands)

    Galagan, Y.

    2018-01-01

    This chapter discusses roll-to-roll (R2R) manufacturing of organic and perovskite solar cells (PSCs), as these emerging photovoltaic (PV) technologies can be fabricated using well-known R2R printing and coating processes that are widely used in the industry. The manufacturing of PV devices starts

  7. Degradation of CIGS solar cells

    NARCIS (Netherlands)

    Theelen, M.J.

    2015-01-01

    Thin film CIGS solar cells and individual layers within these solar cells have been tested in order to assess their long term stability. Alongside with the execution of standard tests, in which elevated temperatures and humidity levels are used, the solar cells have also been exposed to a

  8. World's Most Efficient Solar Cell

    Science.gov (United States)

    World's Most Efficient Solar Cell National Renewable Energy Laboratory, Spectrolab Set Record For , 1999 - A solar cell that can convert sunlight to electricity at a record-setting 32 percent efficiency on Earth. Spectrolab of Sylmar, Calif., "grew" the record-setting solar cell. After

  9. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology (Finland). Dept. of Electrical and Communications Engineering

    1998-12-31

    Photovoltaic research began at the Electron Physics Laboratory of the Helsinki University of Tehnology in 1993, when the laboratory joined the national NEMO 2 research program. During the early stages of the photovoltaic research the main objective was to establish necessary measurement and characterisation routines, as well as to develop the fabrication process. The fabrication process development work has been supported by characterisation and theoretical modelling of the solar cells. Theoretical investigations have been concerned with systematic studies of solar cell parameters, such as diffusion lengths, surface recombination velocities and junction depths. The main result of the modelling and characterisation work is a method which is based on a Laplace transform of the so-called spatial collection efficiency function of the cell. The basic objective of the research has been to develop a fabrication process cheap enough to be suitable for commercial production

  10. Solar cell. Taiyo denchi

    Energy Technology Data Exchange (ETDEWEB)

    Kamihara, T; Kondo, S; Mori, K [Matsushita Electric Industrial Co. Ltd., Osaka (Japan)

    1990-10-23

    This invention provides a solar cell having high resistance to strong incident light and high temperature preservability. Reason of performance degradation of the solar cell in high temperature atmosphere thermally diffuses at the boundary surface of the silicon with metal particles. The method of blocking this thermal diffusion is that the film thickness is of the level that the electrons can pass through the film by a quantum dynamical tunnel effect. In this invention, the construction is that a transparent substrate, a transparent electrode, a P-type amorphous silicon, an I-type amorphous silicon, silica and a collector electrode are sequentially laminated and receives the incident light, thus generating a voltage between the two electrodes. Thickness of silica film is 10-100 microns. Materials of the collector electrode are either single element or alloys of Cs, K, Na, Li, Ba, Mg, Cd, Ta, Al, Mo, Zr, Co, Fe, Cu, Ag, W, Cr, Au and Ni. 13 figs., 1 tab.

  11. Solar cell efficiency measurements

    International Nuclear Information System (INIS)

    Ostoja, P.

    1989-01-01

    Solar cells (and solar modules) have to be tested for their performance by means of sound reliable measurement procedures. The need for such measurements arises at various stages of research, of production, and of photovoltaic systems sizing and dimensioning. In fact, accurate measurements are necessary to the researcher, who studies new materials and new processes, to the manufacturer, who has to control his product and, finally, to the user, who needs sound measurements, in order to be in a position to make effective decisions about what kink of product will be needed and with what critical characteristics. In short, standard measurements that allow cells and modules to be characterized serve as a common language, allowing effective communication about products and requirements. 3 refs

  12. Biocompatible fluorescence-enhanced ZrO2-CdTe quantum dot nanocomposite for in vitro cell imaging

    Science.gov (United States)

    Lu, Zhisong; Zhu, Zhihong; Zheng, Xinting; Qiao, Yan; Guo, Jun; Li, Chang Ming

    2011-04-01

    With advances of quantum dots (QDs) in bioimaging applications, various materials have been used to coat QDs to reduce their nanotoxicity; however, the coating could introduce new toxic sources and quench the fluorescence in bioimaging applications. In this work, ZrO2, an excellent ceramic material with low extinction coefficient and good biocompatibility, is utilized to coat CdTe QDs for the first time. Experimental results show that ZrO2-QD nanocomposites with the size of ~ 30 nm possess enhanced fluorescence emission, lower nanotoxicity and gradually increased fluorescence under 350 nm light illumination. After functionalization with folic acid, they were applied to label cultured HeLa cells effectively. Therefore, the ZrO2-QD nanocomposites could be promising biocompatible nanomaterials with strong fluorescence emission to replace or complement QDs in biomedical applications.

  13. Biocompatible fluorescence-enhanced ZrO2-CdTe quantum dot nanocomposite for in vitro cell imaging

    International Nuclear Information System (INIS)

    Lu Zhisong; Zhu Zhihong; Zheng Xinting; Qiao Yan; Li Changming; Guo Jun

    2011-01-01

    With advances of quantum dots (QDs) in bioimaging applications, various materials have been used to coat QDs to reduce their nanotoxicity; however, the coating could introduce new toxic sources and quench the fluorescence in bioimaging applications. In this work, ZrO 2 , an excellent ceramic material with low extinction coefficient and good biocompatibility, is utilized to coat CdTe QDs for the first time. Experimental results show that ZrO 2 -QD nanocomposites with the size of ∼ 30 nm possess enhanced fluorescence emission, lower nanotoxicity and gradually increased fluorescence under 350 nm light illumination. After functionalization with folic acid, they were applied to label cultured HeLa cells effectively. Therefore, the ZrO 2 -QD nanocomposites could be promising biocompatible nanomaterials with strong fluorescence emission to replace or complement QDs in biomedical applications.

  14. Biocompatible fluorescence-enhanced ZrO{sub 2}-CdTe quantum dot nanocomposite for in vitro cell imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lu Zhisong; Zhu Zhihong; Zheng Xinting; Qiao Yan; Li Changming [School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, 637457 (Singapore); Guo Jun, E-mail: ecmli@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, 639798 (Singapore)

    2011-04-15

    With advances of quantum dots (QDs) in bioimaging applications, various materials have been used to coat QDs to reduce their nanotoxicity; however, the coating could introduce new toxic sources and quench the fluorescence in bioimaging applications. In this work, ZrO{sub 2}, an excellent ceramic material with low extinction coefficient and good biocompatibility, is utilized to coat CdTe QDs for the first time. Experimental results show that ZrO{sub 2}-QD nanocomposites with the size of {approx} 30 nm possess enhanced fluorescence emission, lower nanotoxicity and gradually increased fluorescence under 350 nm light illumination. After functionalization with folic acid, they were applied to label cultured HeLa cells effectively. Therefore, the ZrO{sub 2}-QD nanocomposites could be promising biocompatible nanomaterials with strong fluorescence emission to replace or complement QDs in biomedical applications.

  15. BM Solar Cells

    KAUST Repository

    Firdaus, Yuliar

    2018-05-02

    Fullerene‐based materials are widely used as electron acceptors in organic bulk‐heterojunction solar cells; yet, they have rarely been used as the only photoactive component due to their low absorbance and limited charge generation efficiency. However, blending the wide‐bandgap p‐type material copper (I) thiocyanate (CuSCN) with [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC70BM) leads to the formation of a unique mesostructured p‐n like heterointerface between CuSCN and PC70BM and solar cells with a power conversion efficiency (PCE) of up to 5.4%. Here, we examine in detail the reasons for the surprisingly good device performance and elucidate the charge photogeneration and recombination mechanisms in CuSCN‐based devices with PC70BM as the exclusive light‐absorbing material. Our studies clearly demonstrate that a substantial fraction of the photocurrent in the CuSCN‐based devices results from improved dissociation of fullerene excitons and efficient charge transfer at the CuSCN:PC70BM interface combined with reduced geminate and nongeminate charge recombination losses. Our results have implications beyond the fullerene‐based devices studied here, as they demonstrate that careful selection of a mesostructured p‐type transparent semiconductor paves the path to a new type of efficient single photoactive material solar cells.

  16. BM Solar Cells

    KAUST Repository

    Firdaus, Yuliar; Seitkhan, Akmaral; Eisner, Flurin; Sit, Wai-Yu; Kan, Zhipeng; Wehbe, Nimer; Balawi, Ahmed H.; Yengel, Emre; Karuthedath, Safakath; Laquai, Fré dé ric; Anthopoulos, Thomas D.

    2018-01-01

    Fullerene‐based materials are widely used as electron acceptors in organic bulk‐heterojunction solar cells; yet, they have rarely been used as the only photoactive component due to their low absorbance and limited charge generation efficiency. However, blending the wide‐bandgap p‐type material copper (I) thiocyanate (CuSCN) with [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC70BM) leads to the formation of a unique mesostructured p‐n like heterointerface between CuSCN and PC70BM and solar cells with a power conversion efficiency (PCE) of up to 5.4%. Here, we examine in detail the reasons for the surprisingly good device performance and elucidate the charge photogeneration and recombination mechanisms in CuSCN‐based devices with PC70BM as the exclusive light‐absorbing material. Our studies clearly demonstrate that a substantial fraction of the photocurrent in the CuSCN‐based devices results from improved dissociation of fullerene excitons and efficient charge transfer at the CuSCN:PC70BM interface combined with reduced geminate and nongeminate charge recombination losses. Our results have implications beyond the fullerene‐based devices studied here, as they demonstrate that careful selection of a mesostructured p‐type transparent semiconductor paves the path to a new type of efficient single photoactive material solar cells.

  17. Solar cell. Taiyo denchi

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, S.; Hashimoto, Y. (Canon Inc., Tokyo (Japan))

    1991-05-17

    This invention provides a cheap solar cell having a transparent surface protective layer which satisfies both controversial properties such as high electroconductivity and high water repellency and also abated the reduction of photoelectric conversion. In other words, this invention provides a solar cell having a surface-protective layer prepared by lamination of a mixture of a transparent water-repelling resin and a transparent electroconductive oxide powder; said protective layer is grounded at the surface resistance of 1 {times} 10 {sup 10} ohm or less and the contact angle of water on said protective layer is 90 degrees or more. The transparent water-repelling resin used is a fliorine resin such as PTFE and a silicone resin such as organopolysiloxane. The transparent electrodonductive oxide powder used is tin oxide, indium oxide or a complex compound of ton oxide and antimony oxide. The solar cell of this invention can be used for a long time because the adhesion of the dusts and the contamination by dirty water are restricted. 1 fig., 1 tab.

  18. Transparent solar cell window module

    Energy Technology Data Exchange (ETDEWEB)

    Chau, Joseph Lik Hang; Chen, Ruei-Tang; Hwang, Gan-Lin; Tsai, Ping-Yuan [Nanopowder and Thin Film Technology Center, ITRI South, Industrial Technology Research Institute, Tainan County 709 (China); Lin, Chien-Chu [I-Lai Acrylic Corporation, Tainan City (China)

    2010-03-15

    A transparent solar cell window module based on the integration of traditional silicon solar cells and organic-inorganic nanocomposite material was designed and fabricated. The transparent solar cell window module was composed of a nanocomposite light-guide plate and traditional silicon solar cells. The preparation of the nanocomposite light-guide plate is easy without modification of the traditional casting process, the nanoparticles sol can be added directly to the polymethyl methacrylate (PMMA) monomer syrup during the process. The solar energy collected by this window can be used to power up small household electrical appliances. (author)

  19. Cytotoxicity of CdTe quantum dots in human umbilical vein endothelial cells: the involvement of cellular uptake and induction of pro-apoptotic endoplasmic reticulum stress

    Directory of Open Access Journals (Sweden)

    Yan M

    2016-02-01

    Full Text Available Ming Yan,1,* Yun Zhang,2,* Haiyan Qin,3 Kezhou Liu,1 Miao Guo,1 Yakun Ge,1 Mingen Xu,1 Yonghong Sun,4 Xiaoxiang Zheng4 1Department of Biomedical Engineering, College of Life Information Science and Instrument Engineering, Hangzhou Dianzi University, Hangzhou, 2Basic Medical Sciences, College of Medicine, Shaoxing University, Shaoxing, 3Department of Chemistry, Zhejiang University, 4Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal, Department of Biomedical Engineering, Zhejiang University, Hangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Cadmium telluride quantum dots (CdTe QDs have been proposed to induce oxidative stress, which plays a crucial role in CdTe QDs-mediated mitochondrial-dependent apoptosis in human umbilical vein endothelial cells (HUVECs. However, the direct interactions of CdTe QDs with HUVECs and their potential impairment of other organelles like endoplasmic reticulum (ER in HUVECs are poorly understood. In this study, we reported that the negatively charged CdTe QDs (–21.63±0.91 mV, with good dispersity and fluorescence stability, were rapidly internalized via endocytosis by HUVECs, as the notable internalization could be inhibited up to 95.52% by energy depletion (NaN3/deoxyglucose or low temperature. The endocytosis inhibitors (methyl-β-cyclodextrin, genistein, sucrose, chlorpromazine, and colchicine dramatically decreased the uptake of CdTe QDs by HUVECs, suggesting that both caveolae/raft- and clathrin-mediated endocytosis were involved in the endothelial uptake of CdTe QDs. Using immunocytochemistry, a striking overlap of the internalized CdTe QDs and ER marker was observed, which indicates that QDs may be transported to ER. The CdTe QDs also caused remarkable ER stress responses in HUVECs, confirmed by significant dilatation of ER cisternae, upregulation of ER stress markers GRP78/GRP94, and

  20. Silicon heterojunction solar cells

    CERN Document Server

    Fahrner, W R; Neitzert, H C

    2006-01-01

    The world of today must face up to two contradictory energy problems: on the one hand, there is the sharply growing consumer demand in countries such as China and India. On the other hand, natural resources are dwindling. Moreover, many of those countries which still possess substantial gas and oil supplies are politically unstable. As a result, renewable natural energy sources have received great attention. Among these, solar-cell technology is one of the most promising candidates. However, there still remains the problem of the manufacturing costs of such cells. Many attempts have been made

  1. Silicon Solar Cell Turns 50

    Energy Technology Data Exchange (ETDEWEB)

    Perlin, J.

    2004-08-01

    This short brochure describes a milestone in solar (or photovoltaic, PV) research-namely, the 50th anniversary of the invention of the first viable silicon solar cell by three researchers at Bell Laboratories.

  2. Processing of semiconductors and thin film solar cells using electroplating

    Science.gov (United States)

    Madugu, Mohammad Lamido

    The global need for a clean, sustainable and affordable source of energy has triggered extensive research especially in renewable energy sources. In this sector, photovoltaic has been identified as a cheapest, clean and reliable source of energy. It would be of interest to obtain photovoltaic material in thin film form by using simple and inexpensive semiconductor growth technique such as electroplating. Using this growth technique, four semiconductor materials were electroplated on glass/fluorine-doped tin oxide (FTO) substrate from aqueous electrolytes. These semiconductors are indium selenide (In[x]Sey), zinc sulphide (ZnS), cadmium sulphide (CdS) and cadmium telluride (CdTe). In[x]Se[y] and ZnS were incorporated as buffer layers while CdS and CdTe layers were utilised as window and absorber layers respectively. All materials were grown using two-electrode (2E) system except for CdTe which was grown using 3E and 2E systems for comparison. To fully optimise the growth conditions, the as-deposited and annealed layers from all the materials were characterised for their structural, morphological, optical, electrical and defects structures using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), optical absorption (UV-Vis spectroscopy), photoelectrochemical (PEC) cell measurements, current-voltage (I-V), capacitance-voltage (C-V), DC electrical measurements, ultraviolet photoelectron spectroscopy (UPS) and photoluminescence (PL) techniques. Results show that InxSey and ZnS layers were amorphous in nature and exhibit both n-type and p-type in electrical conduction. CdS layers are n-type in electrical conduction and show hexagonal and cubic phases in both the as-deposited and after annealing process. CdTe layers show cubic phase structure with both n-type and p-type in electrical conduction. CdTe-based solar cell structures with a n-n heterojunction plus large Schottky barrier, as well as multi-layer graded

  3. Effects of various deposition times and RF powers on CdTe thin film growth using magnetron sputtering

    Science.gov (United States)

    Ghorannevis, Z.; Akbarnejad, E.; Ghoranneviss, M.

    2016-09-01

    Cadmium telluride (CdTe) is a p-type II-VI compound semiconductor, which is an active component for producing photovoltaic solar cells in the form of thin films, due to its desirable physical properties. In this study, CdTe film was deposited using the radio frequency (RF) magnetron sputtering system onto a glass substrate. To improve the properties of the CdTe film, effects of two experimental parameters of deposition time and RF power were investigated on the physical properties of the CdTe films. X-ray Diffraction (XRD), atomic force microscopy (AFM) and spectrophotometer were used to study the structural, morphological and optical properties of the CdTe samples grown at different experimental conditions, respectively. Our results suggest that film properties strongly depend on the experimental parameters and by optimizing these parameters, it is possible to tune the desired structural, morphological and optical properties. From XRD data, it is found that increasing the deposition time and RF power leads to increasing the crystallinity as well as the crystal sizes of the grown film, and all the films represent zinc blende cubic structure. Roughness values given from AFM images suggest increasing the roughness of the CdTe films by increasing the RF power and deposition times. Finally, optical investigations reveal increasing the film band gaps by increasing the RF power and the deposition time.

  4. Surface preparation effects on efficient indium-tin-oxide-CdTe and CdS-CdTe heterojunction solar cells

    Science.gov (United States)

    Werthen, J. G.; Fahrenbruch, A. L.; Bube, R. H.; Zesch, J. C.

    1983-05-01

    The effects of CdTe surface preparation and subsequent junction formation have been investigated through characterization of ITO/CdTe and CdS/CdTe heterojunction solar cells formed by electron beam evaporation of indium-tin-oxide (ITO) and CdS onto single crystal p-type CdTe. Surfaces investigated include air-cleaved (110) surfaces, bromine-in-methanol etched (110) and (111) surfaces, and teh latter surfaces subjected to a hydrogen heat treatment. Both air-cleaved and hydrogen heat treated surfaces have a stoichiometric Cd to Te ratio. The ITO/CdTe junction formation process involves an air heat treatment, which ahs serious effects on the behavior of junctions formed on these surfaces. Etched surfaces which have a large excesss of Te, are less affected by the junction formation process and result in ITO/CdTe heterojunctions with solar efficiencies of 9% (Vsc =20 mA/cm2). Use of low-doped CdTe results in junctions characterized by considerably larger open-circuit votages (Voc =0.81 V) which are attributable to increasing diode factors caused by a shift from interfacial recombination to recombination in the depletion region. Resulting solar efficiencies reach 10.5% which is the highest value reported to date for a genuine CdTe heterojunction, CdS/CdTe heterojunctions show a strong dependence on CdTe surface condition, but less influence on the junction formation process. Solar efficiencies of 7.5% on an etched and heat treated surface are observed. All of these ITO/CdTe and CdS/CdTe heterojunctions have been stable for at least 10 months.

  5. Development and prospects of CdS/CdTe solar cell

    International Nuclear Information System (INIS)

    Vaillant, L.

    2008-01-01

    Based on the n-CdS/p-CdTe heterojunction solar cell to thin films, both polycrystalline materials, started to be studied at beginning of the 1970s. However, since the 1960s were structures in which the active material was CdTe. Since then, in almost all proposed cell designs, the main problems encountered related to two important points: recombination losses associated with the main interface and the difficulty to obtain a low resistance ohmic contact with the p-CdTe. For decades, the efficiency of the cell was to rise as I studied and perfected the same from a macroscopic view of the device. Slowly they proposed, manufactured and studied structures responding with higher conversion efficiency. However, in recent years emphasis has been on the need to understand the microscopic mechanisms responsible for the transformations that occur in the device during the manufacturing process of the same. This fact has caused a deepening in the study of polycrystalline nature of the materials making up the cell, using techniques for solving micro and Nano. Special attention have been the borders of grain in the CdTe and studies related to the main junction between CdTe and CdS. This article will attempt to reflect an analysis of the evolution in the design of this type of cell, from its beginnings up to our times.

  6. Cascade Organic Solar Cells

    KAUST Repository

    Schlenker, Cody W.

    2011-09-27

    We demonstrate planar organic solar cells consisting of a series of complementary donor materials with cascading exciton energies, incorporated in the following structure: glass/indium-tin-oxide/donor cascade/C 60/bathocuproine/Al. Using a tetracene layer grown in a descending energy cascade on 5,6-diphenyl-tetracene and capped with 5,6,11,12-tetraphenyl- tetracene, where the accessibility of the π-system in each material is expected to influence the rate of parasitic carrier leakage and charge recombination at the donor/acceptor interface, we observe an increase in open circuit voltage (Voc) of approximately 40% (corresponding to a change of +200 mV) compared to that of a single tetracene donor. Little change is observed in other parameters such as fill factor and short circuit current density (FF = 0.50 ± 0.02 and Jsc = 2.55 ± 0.23 mA/cm2) compared to those of the control tetracene-C60 solar cells (FF = 0.54 ± 0.02 and Jsc = 2.86 ± 0.23 mA/cm2). We demonstrate that this cascade architecture is effective in reducing losses due to polaron pair recombination at donor-acceptor interfaces, while enhancing spectral coverage, resulting in a substantial increase in the power conversion efficiency for cascade organic photovoltaic cells compared to tetracene and pentacene based devices with a single donor layer. © 2011 American Chemical Society.

  7. Cascade Organic Solar Cells

    KAUST Repository

    Schlenker, Cody W.; Barlier, Vincent S.; Chin, Stephanie W.; Whited, Matthew T.; McAnally, R. Eric; Forrest, Stephen R.; Thompson, Mark E.

    2011-01-01

    We demonstrate planar organic solar cells consisting of a series of complementary donor materials with cascading exciton energies, incorporated in the following structure: glass/indium-tin-oxide/donor cascade/C 60/bathocuproine/Al. Using a tetracene layer grown in a descending energy cascade on 5,6-diphenyl-tetracene and capped with 5,6,11,12-tetraphenyl- tetracene, where the accessibility of the π-system in each material is expected to influence the rate of parasitic carrier leakage and charge recombination at the donor/acceptor interface, we observe an increase in open circuit voltage (Voc) of approximately 40% (corresponding to a change of +200 mV) compared to that of a single tetracene donor. Little change is observed in other parameters such as fill factor and short circuit current density (FF = 0.50 ± 0.02 and Jsc = 2.55 ± 0.23 mA/cm2) compared to those of the control tetracene-C60 solar cells (FF = 0.54 ± 0.02 and Jsc = 2.86 ± 0.23 mA/cm2). We demonstrate that this cascade architecture is effective in reducing losses due to polaron pair recombination at donor-acceptor interfaces, while enhancing spectral coverage, resulting in a substantial increase in the power conversion efficiency for cascade organic photovoltaic cells compared to tetracene and pentacene based devices with a single donor layer. © 2011 American Chemical Society.

  8. Industrial Silicon Wafer Solar Cells

    OpenAIRE

    Neuhaus, Dirk-Holger; Münzer, Adolf

    2007-01-01

    In 2006, around 86% of all wafer-based silicon solar cells were produced using screen printing to form the silver front and aluminium rear contacts and chemical vapour deposition to grow silicon nitride as the antireflection coating onto the front surface. This paper reviews this dominant solar cell technology looking into state-of-the-art equipment and corresponding processes for each process step. The main efficiency losses of this type of solar cell are analyzed to demonstrate the future e...

  9. Solar cell materials developing technologies

    CERN Document Server

    Conibeer, Gavin J

    2014-01-01

    This book presents a comparison of solar cell materials, including both new materials based on organics, nanostructures and novel inorganics and developments in more traditional photovoltaic materials. It surveys the materials and materials trends in the field including third generation solar cells (multiple energy level cells, thermal approaches and the modification of the solar spectrum) with an eye firmly on low costs, energy efficiency and the use of abundant non-toxic materials.

  10. Dye solar cell research

    CSIR Research Space (South Africa)

    Cummings, F

    2009-11-01

    Full Text Available Cummings Energy and Processes Materials Science and Manufacturing Council for Scientific and Industrial Research P.O. Box 395 Pretoria 0001, South Africa 27 November 2009 CONTENT head2rightBackground head2rightCSIR Dye Solar Cell Research head2... rightCollaborations and Links © CSIR 2007 www.csir.co.za head2rightAcknowledgements BACKGROUND head2rightSA is dry: Annual rainfall average of 450 mm compared with a world average of 860 mm head2rightOn upside, we have some...

  11. Dye Sensitized Solar Cell, DSSC

    Directory of Open Access Journals (Sweden)

    Pongsatorn Amornpitoksuk

    2003-07-01

    Full Text Available A dye sensitized solar cell is a new type of solar cell. The operating system of this solar cell type is similar to plant’s photosynthesis process. The sensitizer is available for absorption light and transfer electrons to nanocrystalline metal oxide semiconductor. The ruthenium(II complexes with polypyridyl ligands are usually used as the sensitizers in solar cell. At the present time, the complex of [Ru(2,2',2'’-(COOH3- terpy(NCS3] is the most efficient sensitizer. The total photon to current conversion efficiency was approximately 10% at AM = 1.5.

  12. Space Solar Cell Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Measures, characterizes, and analyzes photovoltaic materials and devices. The primary focus is the measurement and characterization of solar cell response...

  13. Quantum Junction Solar Cells

    KAUST Repository

    Tang, Jiang

    2012-09-12

    Colloidal quantum dot solids combine convenient solution-processing with quantum size effect tuning, offering avenues to high-efficiency multijunction cells based on a single materials synthesis and processing platform. The highest-performing colloidal quantum dot rectifying devices reported to date have relied on a junction between a quantum-tuned absorber and a bulk material (e.g., TiO 2); however, quantum tuning of the absorber then requires complete redesign of the bulk acceptor, compromising the benefits of facile quantum tuning. Here we report rectifying junctions constructed entirely using inherently band-aligned quantum-tuned materials. Realizing these quantum junction diodes relied upon the creation of an n-type quantum dot solid having a clean bandgap. We combine stable, chemically compatible, high-performance n-type and p-type materials to create the first quantum junction solar cells. We present a family of photovoltaic devices having widely tuned bandgaps of 0.6-1.6 eV that excel where conventional quantum-to-bulk devices fail to perform. Devices having optimal single-junction bandgaps exhibit certified AM1.5 solar power conversion efficiencies of 5.4%. Control over doping in quantum solids, and the successful integration of these materials to form stable quantum junctions, offers a powerful new degree of freedom to colloidal quantum dot optoelectronics. © 2012 American Chemical Society.

  14. Effect of In Situ Thermal Annealing on Structural, Optical, and Electrical Properties of CdS/CdTe Thin Film Solar Cells Fabricated by Pulsed Laser Deposition

    Directory of Open Access Journals (Sweden)

    Alaa Ayad Al-mebir

    2016-01-01

    Full Text Available An in situ thermal annealing process (iTAP has been introduced before the common ex situ cadmium chloride (CdCl2 annealing to improve crystal quality and morphology of the CdTe thin films after pulsed laser deposition of CdS/CdTe heterostructures. A strong correlation between the two annealing processes was observed, leading to a profound effect on the performance of CdS/CdTe thin film solar cells. Atomic force microscopy and Raman spectroscopy show that the iTAP in the optimal processing window produces considerable CdTe grain growth and improves the CdTe crystallinity, which results in significantly improved optoelectronic properties and quantum efficiency of the CdS/CdTe solar cells. A power conversion efficiency of up to 7.0% has been obtained on thin film CdS/CdTe solar cells of absorber thickness as small as 0.75 μm processed with the optimal iTAP at 450°C for 10–20 min. This result illustrates the importance of controlling microstructures of CdTe thin films and iTAP provides a viable approach to achieve such a control.

  15. Emerging Solar Technologies: Perovskite Solar Cell

    Indian Academy of Sciences (India)

    energy technologies and ... cost-effective and feasible non-silicon solar cell technologies. ..... storing in the air for long periods, and the stability reached up to .... [12] Y Liu, L A Renna, M Bag, Z A Page, P Kim, J Choi, T Emrick, D Venkatara-.

  16. Electro-Plating and Characterisation of CdTe Thin Films Using CdCl2 as the Cadmium Source

    Directory of Open Access Journals (Sweden)

    Nor A. Abdul-Manaf

    2015-09-01

    Full Text Available Cadmium telluride (CdTe thin films have been successfully prepared from an aqueous electrolyte bath containing cadmium chloride (CdCl2·H2O and tellurium dioxide (TeO2 using an electrodeposition technique. The structural, electrical, morphological and optical properties of these thin films have been characterised using X-ray diffraction (XRD, Raman spectroscopy, optical profilometry, DC current-voltage (I-V measurements, photoelectrochemical (PEC cell measurement, scanning electron microscopy (SEM, atomic force microscopy (AFM and UV-Vis spectrophotometry. It is observed that the best cathodic potential is 698 mV with respect to standard calomel electrode (SCE in a three electrode system. Structural analysis using XRD shows polycrystalline crystal structure in the as-deposited CdTe thin films and the peaks intensity increase after CdCl2 treatment. PEC cell measurements show the possibility of growing p-, i- and n-type CdTe layers by varying the growth potential during electrodeposition. The electrical resistivity of the as-deposited layers are in the order of 104 Ω·cm. SEM and AFM show that the CdCl2 treated samples are more roughness and have larger grain size when compared to CdTe grown by CdSO4 precursor. Results obtained from the optical absorption reveal that the bandgap of as-deposited CdTe (1.48–1.52 eV reduce to (1.45–1.49 eV after CdCl2 treatment. Full characterisation of this material is providing new information on crucial CdCl2 treatment of CdTe thin films due to its built-in CdCl2 treatment during the material growth. The work is progressing to fabricate solar cells with this material and compare with CdTe thin films grown by conventional sulphate precursors.

  17. Thin-film solar cell

    NARCIS (Netherlands)

    Metselaar, J.W.; Kuznetsov, V.I.

    1998-01-01

    The invention relates to a thin-film solar cell provided with at least one p-i-n junction comprising at least one p-i junction which is at an angle alpha with that surface of the thin-film solar cell which collects light during operation and at least one i-n junction which is at an angle beta with

  18. Electroplating of CdTe Thin Films from Cadmium Sulphate Precursor and Comparison of Layers Grown by 3-Electrode and 2-Electrode Systems

    Directory of Open Access Journals (Sweden)

    Imyhamy M. Dharmadasa

    2017-01-01

    Full Text Available Electrodeposition of CdTe thin films was carried out from the late 1970s using the cadmium sulphate precursor. The solar energy group at Sheffield Hallam University has carried out a comprehensive study of CdTe thin films electroplated using cadmium sulfate, cadmium nitrate and cadmium chloride precursors, in order to select the best electrolyte. Some of these results have been published elsewhere, and this manuscript presents the summary of the results obtained on CdTe layers grown from cadmium sulphate precursor. In addition, this research program has been exploring the ways of eliminating the reference electrode, since this is a possible source of detrimental impurities, such as K+ and Ag+ for CdS/CdTe solar cells. This paper compares the results obtained from CdTe layers grown by three-electrode (3E and two-electrode (2E systems for their material properties and performance in CdS/CdTe devices. Thin films were characterized using a wide range of analytical techniques for their structural, morphological, optical and electrical properties. These layers have also been used in device structures; glass/FTO/CdS/CdTe/Au and CdTe from both methods have produced solar cells to date with efficiencies in the region of 5%–13%. Comprehensive work carried out to date produced comparable and superior devices fabricated from materials grown using 2E system.

  19. Solar cell reloaded; Solarzelle reloaded

    Energy Technology Data Exchange (ETDEWEB)

    Iken, Joern

    2013-06-06

    Who comes up with something special, he may also compete with Chinese. The German-Scandinavian company Innotech Solar extends its solar module production capacity even in the midst of the crisis. Innotech Solar restores damaged cells. For this, the damaged areas are isolated and inactivated. [German] Wer sich etwas Besonderes einfallen laesst, kann auch mit chinesischer Konkurrenz bestehen. Das deutsch-skandinavische Unternehmen Innotech Solar erweitert seine Kapazitaet zur Modulherstellung sogar mitten in der Krise. Das Geschaeftsmodell der Innotech Solar sieht vor, vorgeschaedigte Solarzellen wiederherzustellen. Dafuer werden die schadhaften Stellen isoliert und stillgelegt.

  20. Upconversion in solar cells

    Science.gov (United States)

    2013-01-01

    The possibility to tune chemical and physical properties in nanosized materials has a strong impact on a variety of technologies, including photovoltaics. One of the prominent research areas of nanomaterials for photovoltaics involves spectral conversion. Modification of the spectrum requires down- and/or upconversion or downshifting of the spectrum, meaning that the energy of photons is modified to either lower (down) or higher (up) energy. Nanostructures such as quantum dots, luminescent dye molecules, and lanthanide-doped glasses are capable of absorbing photons at a certain wavelength and emitting photons at a different (shorter or longer) wavelength. We will discuss upconversion by lanthanide compounds in various host materials and will further demonstrate upconversion to work for thin-film silicon solar cells. PMID:23413889

  1. Back wall solar cell

    Science.gov (United States)

    Brandhorst, H. W., Jr. (Inventor)

    1978-01-01

    A solar cell is disclosed which comprises a first semiconductor material of one conductivity type with one face having the same conductivity type but more heavily doped to form a field region arranged to receive the radiant energy to be converted to electrical energy, and a layer of a second semiconductor material, preferably highly doped, of opposite conductivity type on the first semiconductor material adjacent the first semiconductor material at an interface remote from the heavily doped field region. Instead of the opposite conductivity layer, a metallic Schottky diode layer may be used, in which case no additional back contact is needed. A contact such as a gridded contact, previous to the radiant energy may be applied to the heavily doped field region of the more heavily doped, same conductivity material for its contact.

  2. Photon management in solar cells

    CERN Document Server

    Rau, Uwe; Gombert, Andreas

    2015-01-01

    Written by renowned experts in the field of photon management in solar cells, this one-stop reference gives an introduction to the physics of light management in solar cells, and discusses the different concepts and methods of applying photon management. The authors cover the physics, principles, concepts, technologies, and methods used, explaining how to increase the efficiency of solar cells by splitting or modifying the solar spectrum before they absorb the sunlight. In so doing, they present novel concepts and materials allowing for the cheaper, more flexible manufacture of solar cells and systems. For educational purposes, the authors have split the reasons for photon management into spatial and spectral light management. Bridging the gap between the photonics and the photovoltaics communities, this is an invaluable reference for materials scientists, physicists in industry, experimental physicists, lecturers in physics, Ph.D. students in physics and material sciences, engineers in power technology, appl...

  3. Three-dimensional minority carrier lifetime mapping of thin film semiconductors for solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Hardin, Brian [PLANT PV, Inc., Belmont, CA (United States); Peters, Craig [PLANT PV, Inc., Belmont, CA (United States); Barnard, Edward [PLANT PV, Inc., Belmont, CA (United States)

    2015-09-30

    This project addresses the difficulty of accurately measuring charge carrier dynamics in novel semiconductor materials for thin film photovoltaic cells. We have developed a two- photon lifetime tomography technique to separate bulk minority carrier lifetime from surface recombination effects and effects of recombination at sub-surface defects. This technique also enables us to characterize how local defects such as grain boundaries– buried below the surface of a sample–affect carrier lifetimes in the active layer, dynamics that have been previously inaccessible. We have applied this newly developed technique to illuminate how CdCl2 treatment improves CdTe PV efficiency. From striking 3D lifetime tomography maps, a clear, sub- surface understanding emerges of the photophysical changes that occur in CdTe active medium following exposure to CdCl2, a standard step in the fabrication of high-efficiency CdTe-based solar cells. This work demonstrates a well-defined method to quantify grain-boundary, interface, and bulk recombination in CdTe and other optically-active polycrystalline semiconductor materials; information that can provide critical information to the development of next- generation photovoltaics and many other semiconductor technologies.

  4. Nanostructuring of Solar Cell Surfaces

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk

    Solar energy is by far the most abundant renewable energy source available, but the levelized cost of solar energy is still not competitive with that of fossil fuels. Therefore there is a need to improve the power conversion effciency of solar cells without adding to the production cost. The main...... objective of this PhD thesis is to develop nanostructured silicon (Si) solar cells with higher power conversion efficiency using only scalable and cost-efficient production methods. The nanostructures, known as 'black silicon', are fabricated by single-step, maskless reactive ion etching and used as front...... texturing of different Si solar cells. Theoretically the nanostructure topology may be described as a graded refractive index in a mean-field approximation between air and Si. The optical properties of the developed black Si were simulated and experimentally measured. Total AM1.5G-weighted average...

  5. Dust Removal from Solar Cells

    Science.gov (United States)

    Ashpis, David E. (Inventor)

    2015-01-01

    A solar panel cleaning device includes a solar panel having a plurality of photovoltaic cells arranged in rows and embedded in the solar panel with space between the rows. A transparent dielectric overlay is affixed to the solar panel. A plurality of electrode pairs each of which includes an upper and a lower electrode are arranged on opposite sides of the transparent dielectric and are affixed thereto. The electrodes may be transparent electrodes which may be arranged without concern for blocking sunlight to the solar panel. The solar panel may be a dielectric and its dielectric properties may be continuously and spatially variable. Alternatively the dielectric used may have dielectric segments which produce different electrical field and which affects the wind "generated."

  6. Optimization of Monocrystalline MgxCd1-xTe/MgyCd1-yTe Double-Heterostructure Solar Cells

    Science.gov (United States)

    Becker, Jacob J.

    Polycrystalline CdS/CdTe solar cells continue to dominate the thin-film photovoltaics industry with an achieved record efficiency of over 22% demonstrated by First Solar, yet monocrystalline CdTe devices have received considerably less attention over the years. Monocrystalline CdTe double-heterostructure solar cells show great promise with respect to addressing the problem of low Voc with the passing of the 1 V benchmark. Rapid progress has been made in driving the efficiency in these devices ever closer to the record presently held by polycrystalline thin-films. This achievement is primarily due to the utilization of a remote p-n heterojunction in which the heavily doped contact materials, which are so problematic in terms of increasing non-radiative recombination inside the absorber, are moved outside of the CdTe double heterostructure with two MgyCd1-yTe barrier layers to provide confinement and passivation at the CdTe surfaces. Using this design, the pursuit and demonstration of efficiencies beyond 20% in CdTe solar cells is reported through the study and optimization of the structure barriers, contacts layers, and optical design. Further development of a wider bandgap MgxCd1-xTe solar cell based on the same design is included with the intention of applying this knowledge to the development of a tandem solar cell constructed on a silicon subcell. The exploration of different hole-contact materials--ZnTe, CuZnS, and a-Si:H--and their optimization is presented throughout the work. Devices utilizing a-Si:H hole contacts exhibit open-circuit voltages of up to 1.11 V, a maximum total-area efficiency of 18.5% measured under AM1.5G, and an active-area efficiency of 20.3% for CdTe absorber based devices. The achievement of voltages beyond 1.1V while still maintaining relatively high fill factors with no rollover, either before or after open-circuit, is a promising indicator that this approach can result in devices surpassing the 22% record set by polycrystalline

  7. Solar cell with back side contacts

    Science.gov (United States)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

    2013-12-24

    A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

  8. Industrial Silicon Wafer Solar Cells

    Directory of Open Access Journals (Sweden)

    Dirk-Holger Neuhaus

    2007-01-01

    Full Text Available In 2006, around 86% of all wafer-based silicon solar cells were produced using screen printing to form the silver front and aluminium rear contacts and chemical vapour deposition to grow silicon nitride as the antireflection coating onto the front surface. This paper reviews this dominant solar cell technology looking into state-of-the-art equipment and corresponding processes for each process step. The main efficiency losses of this type of solar cell are analyzed to demonstrate the future efficiency potential of this technology. In research and development, more various advanced solar cell concepts have demonstrated higher efficiencies. The question which arises is “why are new solar cell concepts not transferred into industrial production more frequently?”. We look into the requirements a new solar cell technology has to fulfill to have an advantage over the current approach. Finally, we give an overview of high-efficiency concepts which have already been transferred into industrial production.

  9. Performance of Photovoltaic Modules of Different Solar Cells

    Directory of Open Access Journals (Sweden)

    Ankita Gaur

    2013-01-01

    Full Text Available In this paper, an attempt of performance evaluation of semitransparent and opaque photovoltaic (PV modules of different generation solar cells, having the maximum efficiencies reported in the literature at standard test conditions (STC, has been carried out particularly for the months of January and June. The outdoor performance is also evaluated for the commercially available semitransparent and opaque PV modules. Annual electrical energy, capitalized cost, annualized uniform cost (unacost, and cost per unit electrical energy for both types of solar modules, namely, semitransparent and opaque have also been computed along with their characteristics curves. Semitransparent PV modules have shown higher efficiencies compared to the opaque ones. Calculations show that for the PV modules made in laboratory, CdTe exhibits the maximum annual electrical energy generation resulting into minimum cost per unit electrical energy, whereas a-Si/nc-Si possesses the maximum annual electrical energy generation giving minimum cost per unit electrical energy when commercially available solar modules are concerned. CIGS has shown the lowest capitalized cost over all other PV technologies.

  10. Effects of anodic aluminum oxide membrane on performance of nanostructured solar cells

    International Nuclear Information System (INIS)

    Dang, Hongmei; Singh, Vijay

    2015-01-01

    Three nanowire solar cell device configurations have been fabricated to demonstrate the effects of the host anodized aluminum oxide (AAO) membrane on device performance. The three configurations show similar transmittance spectra, indicating that AAO membrane has negligible optical absorption. Power conversion efficiency (PCE) of the device is studied as a function of the carrier transport and collection in cell structures with and without AAO membrane. Free standing nanowire solar cells exhibit PCE of 9.9%. Through inclusion of AAO in solar cell structure, interface defects and traps caused by humidity and oxygen are reduced, and direct contact of CdTe tentacles with SnO 2 and formation of micro shunt shorts are prevented; hence PCE is improved to 11.1%–11.3%. Partially embedded nanowire solar cells further reduce influence of non-ideal and non-uniform nanowire growth and generate a large amount of carriers in axial direction and also a small quantity of carriers in lateral direction, thus becoming a promising solar cell structure. Thus, including AAO membrane in solar cell structure provides favorable electro-optical properties as well as mechanical advantages. (paper)

  11. Effects of anodic aluminum oxide membrane on performance of nanostructured solar cells

    Science.gov (United States)

    Dang, Hongmei; Singh, Vijay

    2015-05-01

    Three nanowire solar cell device configurations have been fabricated to demonstrate the effects of the host anodized aluminum oxide (AAO) membrane on device performance. The three configurations show similar transmittance spectra, indicating that AAO membrane has negligible optical absorption. Power conversion efficiency (PCE) of the device is studied as a function of the carrier transport and collection in cell structures with and without AAO membrane. Free standing nanowire solar cells exhibit PCE of 9.9%. Through inclusion of AAO in solar cell structure, interface defects and traps caused by humidity and oxygen are reduced, and direct contact of CdTe tentacles with SnO2 and formation of micro shunt shorts are prevented; hence PCE is improved to 11.1%-11.3%. Partially embedded nanowire solar cells further reduce influence of non-ideal and non-uniform nanowire growth and generate a large amount of carriers in axial direction and also a small quantity of carriers in lateral direction, thus becoming a promising solar cell structure. Thus, including AAO membrane in solar cell structure provides favorable electro-optical properties as well as mechanical advantages.

  12. Radiation hard solar cell and array

    International Nuclear Information System (INIS)

    Russell, R.L.

    1975-01-01

    A power generating solar cell for a spacecraft solar array is hardened against transient response to nuclear radiation while permitting normal operation of the cell in a solar radiation environment by shunting the cell with a second solar cell whose contacts are reversed relative to the power cell to form a cell module, exposing the power cell only to the solar radiation in a solar radiation environment to produce an electrical output at the module terminals, and exposing both cells to the nuclear radiation in a nuclear radiation environment so that the radiation induced currents generated by the cells suppress one another

  13. Solar electron source and thermionic solar cell

    Directory of Open Access Journals (Sweden)

    Parham Yaghoobi

    2012-12-01

    Full Text Available Common solar technologies are either photovoltaic/thermophotovoltaic, or use indirect methods of electricity generation such as boiling water for a steam turbine. Thermionic energy conversion based on the emission of electrons from a hot cathode into vacuum and their collection by an anode is also a promising route. However, thermionic solar conversion is extremely challenging as the sunlight intensity is too low for heating a conventional cathode to thermionic emission temperatures in a practical manner. Therefore, compared to other technologies, little has been done in this area, and the devices have been mainly limited to large experimental apparatus investigated for space power applications. Based on a recently observed “Heat Trap” effect in carbon nanotube arrays, allowing their efficient heating with low-power light, we report the first compact thermionic solar cell. Even using a simple off-the-shelf focusing lens, the device delivered over 1 V across a load. The device also shows intrinsic storage capacity.

  14. Photoluminescence measurement of polycrystalline CdTe made of high purity source material

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, Hannes; Kraft, Christian; Heisler, Christoph; Geburt, Sebastian; Ronning, Carsten; Wesch, Werner [Institute of Solid State Physics, Friedrich Schiller Universitaet Jena, Helmholtzweg 3, 07743 Jena (Germany)

    2012-07-01

    CdTe is a common material for thin film solar cells. However, the mainly used CdTe source material is known to contain a high number of intrinsic defects and impurities. In this work we investigate the defect structure of high purity CdTe by means of Photoluminescence, which is a common method to detect the energy levels of defects in the band gap of semiconductors. We used a 633 nm HeNe-Laser at sample temperatures of 8 K. The examined samples were processed in a new vacuum system based on the PVD method. They yield significantly different spectra on as-grown samples compared to those measured on samples which are grown by the standard process, since the double peak at 1.55 eV was hardly detectable and the A-center correlated transition vanished. Instead a peak at 1.50 eV with pronounced phonon coupling was observed. The 1.50 eV peak is known from other measurements but has not been characterized so far. The intention of this work is to characterize this new feature and the influence of post deposition treatments of the CdTe layers on the PL spectra.

  15. About the use of photoacoustic spectroscopy for the optical characterization of semiconductor thin films: CdTe

    International Nuclear Information System (INIS)

    Marin, E.; Calderon, A.; Vigil G, O.; Sastre, J.; Contreras P, G.; Aguilar H, J.; Saucedo, E.; Ruiz, C.M.

    2006-01-01

    CdTe has been used satisfactorily in multiple and diverse technological applications such as detectors of X and gamma rays that operate at room temperature, for digital imagenology of X rays with medical and industrial applications and as active part in CdTe/CdS solar cells. In form of films, CdTe is generally grown with thicknesses ranging between 3 and 15 μm, for which it is difficult to measure, by means of optical techniques, absorption coefficients greater than 10 3 cm -1 because nearly full absorption of light should occur below 800 nm. The exact determination of the optical absorption coefficient in detectors on the basis of CdTe is very important since this parameter determines the absorption length at which 90% of the photons with energies over the forbidden zone of the CdTe will be absorbed by this. In CdS/CdTe polycrystalline solar cells the greater efficiency of conversion have been reported for film thicknesses of 10 mm, however, the optimal value of this parameter depends strongly on the method and the variables of growth. The optical absorption coefficient spectrum can be determined by several methods, often involving several approximations and the knowledge of some minority carrier related electronic parameters that reduce their application in general way. In this work we propose to determine the absorption coefficient in CdTe thin films by photoacoustic spectroscopy (PAS), because this technique allow us to obtain the optical absorption spectra in thicker layers and therefore the study of the influence of the several growth and post-growth processes in the optical properties of this thin films. We measure by PAS the optical-absorption coefficients of CdTe thin films in the spectral region near the fundamental absorption edge ranging from 1.0 to 2.4 eV using an open cell in the transmission configuration. The films were deposited on different substrates by the CSVT-HW (hot wall) technique. In order to study the influence of several growth

  16. About the use of photoacoustic spectroscopy for the optical characterization of semiconductor thin films: CdTe

    Energy Technology Data Exchange (ETDEWEB)

    Marin, E.; Calderon, A. [CICATA-IPN, Av. Legaria 694, 11500 Mexico D.F. (Mexico); Vigil G, O.; Sastre, J.; Contreras P, G.; Aguilar H, J. [ESFM-IPN, 07738 Mexico D.F. (Mexico); Saucedo, E.; Ruiz, C.M. [Departamento de Fisica de Materiales, Facultad de Ciencias, Universidad Autonoma de Madrid, 28049 Madrid (Spain)

    2006-07-01

    CdTe has been used satisfactorily in multiple and diverse technological applications such as detectors of X and gamma rays that operate at room temperature, for digital imagenology of X rays with medical and industrial applications and as active part in CdTe/CdS solar cells. In form of films, CdTe is generally grown with thicknesses ranging between 3 and 15 {mu}m, for which it is difficult to measure, by means of optical techniques, absorption coefficients greater than 10{sup 3} cm{sup -1} because nearly full absorption of light should occur below 800 nm. The exact determination of the optical absorption coefficient in detectors on the basis of CdTe is very important since this parameter determines the absorption length at which 90% of the photons with energies over the forbidden zone of the CdTe will be absorbed by this. In CdS/CdTe polycrystalline solar cells the greater efficiency of conversion have been reported for film thicknesses of 10 mm, however, the optimal value of this parameter depends strongly on the method and the variables of growth. The optical absorption coefficient spectrum can be determined by several methods, often involving several approximations and the knowledge of some minority carrier related electronic parameters that reduce their application in general way. In this work we propose to determine the absorption coefficient in CdTe thin films by photoacoustic spectroscopy (PAS), because this technique allow us to obtain the optical absorption spectra in thicker layers and therefore the study of the influence of the several growth and post-growth processes in the optical properties of this thin films. We measure by PAS the optical-absorption coefficients of CdTe thin films in the spectral region near the fundamental absorption edge ranging from 1.0 to 2.4 eV using an open cell in the transmission configuration. The films were deposited on different substrates by the CSVT-HW (hot wall) technique. In order to study the influence of several

  17. Ninth workshop on crystalline silicon solar cell materials and processes: Summary discussion sessions

    International Nuclear Information System (INIS)

    Sopori, B.; Tan, T.; Swanson, D.; Rosenblum, M.; Sinton, R.

    1999-01-01

    This report is a summary of the panel discussions included with the Ninth Workshop on Crystalline Silicon Solar Cell Materials and Processes. The theme for the workshop was ''R and D Challenges and Opportunities in Si Photovoltaics''. This theme was chosen because it appropriately reflects a host of challenges that the growing production of Si photovoltaics will be facing in the new millennium. The anticipated challenges will arise in developing strategies for cost reduction, increased production, higher throughput per manufacturing line, new sources of low-cost Si, and the introduction of new manufacturing processes for cell production. At the same time, technologies based on CdTe and CIS will come on line posing new competition. With these challenges come new opportunities for Si PV to wean itself from the microelectronics industry, to embark on a more aggressive program in thin-film Si solar cells, and to try new approaches to process monitoring

  18. Concentrator-solar-cell development

    Science.gov (United States)

    Grenon, L.

    1982-07-01

    A program is described which is a continuation of earlier programs for the development of high-efficiency, low-cost, silicon concentrator solar cells. The base-line process steps and process sequences identified in these earlier contracts were evaluated and specific processes reviewed. In particular, emphasis on the use of Czochralski-grown silicon wafers rather than float-zone wafers were examined. Additionally, a study of the trade-offs between textured and nontextured cells was initiated, and the limits within which the low-cost plated nickel copper metallization can be used in concentrator solar cell applications was identified.

  19. Thin-film solar cells

    International Nuclear Information System (INIS)

    Aberle, Armin G.

    2009-01-01

    The rapid progress that is being made with inorganic thin-film photovoltaic (PV) technologies, both in the laboratory and in industry, is reviewed. While amorphous silicon based PV modules have been around for more than 20 years, recent industrial developments include the first polycrystalline silicon thin-film solar cells on glass and the first tandem solar cells based on stacks of amorphous and microcrystalline silicon films ('micromorph cells'). Significant thin-film PV production levels are also being set up for cadmium telluride and copper indium diselenide.

  20. Solar cell power source system

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yoichi; Toma, Kunio; Fukuwa, Shinji

    1988-05-14

    This invention aims to supply a power source system with stable power output by reducing the power loss due to switching in the voltage stabilization even when the power source is a solar cell with frequent voltage variation. For this purpose, in a solar cell power source system consisting of a solar cell, a storage battery, a switching regulator placed between the storage cell and the load, and a load, arrangement was made that, by judging the input voltage from the storage battery, switch-acting the transistor of the switching regulator, if the input voltage is higher than the specified voltage; is the input voltage is lower than the specified voltage, the transistor is put in a full-on state. By this, the supply voltage can be stabilized even when the voltage fluctuates, and system gets more efficient as the switching loss decreases in the voltage stabilizing means. (1 fig)

  1. Solar energy utilization by solar cells and superblack absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, D; Selders, M

    1975-10-31

    A review is presented of the physical principles responsible for the characteristics of solar cells, with particular reference to Si homojunction and CdS--Cu/sub 2/S thin film devices. Electric power generation from solar cells still appears uncompetitive economically except in special circumstances, but heating from solar energy using selective absorbers with low reemission is more promising.

  2. Rehydrating dye sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Christian Hellert

    2017-05-01

    Full Text Available Dye sensitized solar cells (DSSCs are silicon free, simply producible solar cells. Longevity, however, is a longstanding problem for DSSCs. Due to liquid electrolytes being commonly used, evaporation of the electrolyte causes a dramatic drop in electric output as cells continue to be used unmaintained. Stopping evaporation has been tried in different ways in the past, albeit with differing degrees of success. In a recent project, a different route was chosen, exploring ways of revitalizing DSSCs after varying periods of usage. For this, we focused on rehydration of the cells using distilled water as well as the electrolyte contained in the cells. The results show a significant influence of these rehydration procedures on the solar cell efficiency. In possible applications of DSSCs in tents etc., morning dew may thus be used for rehydration of solar cells. Refillable DSSCs can also be used in tropical climates or specific types of farms and greenhouses where high humidity serves the purpose of rehydrating DSSCs.

  3. Plastic solar cells : understanding the special additive

    NARCIS (Netherlands)

    van Franeker, H.; Janssen, R.A.J.

    2015-01-01

    Solar cells use freely available sunlight to make electricity. At the present time, solar electricity does not come cheap, because solar panels are rather expensive. Now imagine that we could reduce costs by printing solar panels like we print newspapers! We can do just that with plastic solar

  4. Characterization of multicrystalline solar cells

    International Nuclear Information System (INIS)

    Malik, A.Q.; Chong Chew Hah; Chan Siang Khwang; Tan Kha Sheng; Lim Chee Ming

    2006-01-01

    The evaluation and assessment of the performance of photovoltaic (PV) cells in terms of measurable parameters requires the measurement of the current as a function of voltage, temperature, intensity, wind speed and spectrum. Most noticeable of all these parameters in the PV conversion efficiency η, defined as the maximum electrical power P max produced by the PV cell divided by the incident photon power P in which is measured with respect to standard test conditions (Sc). These conditions refer to the spectrum (AM 1.5), solar radiation intensity (1000 Wm -2 ), cell temperature (25 ± 2 degree C) and wind speed (2 mph). Tests under STC are carried out in the laboratory at a controlled environment. There have been several studies that analyze uncertainties in the laboratory measurement of solar cell efficiencies using different solar simulators and their transference to operational situations. Our preliminary results demonstrate that the short circuit current (I SC ) of the solar cell decreases when irradiance is less than 1000 Wm -2 irrespective of the working temperature of the cell

  5. Characterisation of multicrystalline solar cells

    Directory of Open Access Journals (Sweden)

    A.Q. Malik

    2017-10-01

    Full Text Available The evaluation and assessment of the performance of photovoltaic (PV cells in terms of measurable parameters requires the measurement of the current as a function of voltage, temperature, intensity, wind speed and spectrum. Mo st noticeable of all these parameters is the PV conversion efficiency η, defined as the maximum electrical power Pmax produced by the PV cell divided by the incident photon power P in which is measured with respect to standard test conditions (STC. These conditions refer to the spectrum (AM 1.5, solar radiation intensity (1000 Wm-2, cell temperature (25 ±2oC and wind speed (2 mph. Tests under STC are carried out in the laboratory at a controlled environment. There have been several studies that analyze uncertainties in the laboratory measurement of solar cell efficiencies using different solar simulators and their transference to operational situations. Our preliminary results demonstratethat the short circuit current (ISC of the solar cell decreases when irradiance is less than 1000 Wm-2 irrespective of the working temperature of the cell.

  6. Comparison of structural properties of thermally evaporated CdTe thin films on different substrates

    International Nuclear Information System (INIS)

    Tariq, G.H.; Anis-ur-Rehman, M.

    2011-01-01

    The direct energy band gap in the range of 1.5 eV and the high absorption coefficient (105 cm/sup -1/) makes Cadmium Telluride (CdTe) a suitable material for fabrication of thin film solar cells. Thin film solar cells based on CdTe (1 cm area) achieved efficiency of 15.6% on a laboratory scale. CdTe thin films were deposited by thermal evaporation technique under vacuum 2 X 10/sup -5/mbar on glass and stainless steel (SS) substrates. During deposition substrates temperature was kept same at 200 deg. C for all samples. The structural properties were determined by the X-ray Diffraction (XRD) patterns. All samples exhibit polycrystalline nature. Dependence of different structural parameters such as lattice parameter, micro strain, and grain size and dislocation density on thickness was studied. Also the influence of the different substrates on these parameters was investigated. The analysis showed that the preferential orientation of films was dependent on the substrate type. (author)

  7. New mounting improves solar-cell efficiency

    Science.gov (United States)

    Shepard, N. F., Jr.

    1980-01-01

    Method boosts output by about 20 percent by trapping and redirecting solar radiation without increasing module depth. Mounted solar-cell array is covered with internally reflecting plate. Plate is attached to each cell by transparent adhesive, and space between cells is covered with layer of diffusely reflecting material. Solar energy falling on space between cells is diffused and reflected internally by plate until it is reflected onto solar cell.

  8. Compositionally Graded Absorber for Efficient and Stable Near-Infrared-Transparent Perovskite Solar Cells.

    Science.gov (United States)

    Fu, Fan; Pisoni, Stefano; Weiss, Thomas P; Feurer, Thomas; Wäckerlin, Aneliia; Fuchs, Peter; Nishiwaki, Shiro; Zortea, Lukas; Tiwari, Ayodhya N; Buecheler, Stephan

    2018-03-01

    Compositional grading has been widely exploited in highly efficient Cu(In,Ga)Se 2 , CdTe, GaAs, quantum dot solar cells, and this strategy has the potential to improve the performance of emerging perovskite solar cells. However, realizing and maintaining compositionally graded perovskite absorber from solution processing is challenging. Moreover, the operational stability of graded perovskite solar cells under long-term heat/light soaking has not been demonstrated. In this study, a facile partial ion-exchange approach is reported to achieve compositionally graded perovskite absorber layers. Incorporating compositional grading improves charge collection and suppresses interface recombination, enabling to fabricate near-infrared-transparent perovskite solar cells with power conversion efficiency of 16.8% in substrate configuration, and demonstrate 22.7% tandem efficiency with 3.3% absolute gain when mechanically stacked on a Cu(In,Ga)Se 2 bottom cell. Non-encapsulated graded perovskite device retains over 93% of its initial efficiency after 1000 h operation at maximum power point at 60 °C under equivalent 1 sun illumination. The results open an avenue in exploring partial ion-exchange to design graded perovskite solar cells with improved efficiency and stability.

  9. Compositionally Graded Absorber for Efficient and Stable Near‐Infrared‐Transparent Perovskite Solar Cells

    Science.gov (United States)

    Pisoni, Stefano; Weiss, Thomas P.; Feurer, Thomas; Wäckerlin, Aneliia; Fuchs, Peter; Nishiwaki, Shiro; Zortea, Lukas; Tiwari, Ayodhya N.

    2018-01-01

    Abstract Compositional grading has been widely exploited in highly efficient Cu(In,Ga)Se2, CdTe, GaAs, quantum dot solar cells, and this strategy has the potential to improve the performance of emerging perovskite solar cells. However, realizing and maintaining compositionally graded perovskite absorber from solution processing is challenging. Moreover, the operational stability of graded perovskite solar cells under long‐term heat/light soaking has not been demonstrated. In this study, a facile partial ion‐exchange approach is reported to achieve compositionally graded perovskite absorber layers. Incorporating compositional grading improves charge collection and suppresses interface recombination, enabling to fabricate near‐infrared‐transparent perovskite solar cells with power conversion efficiency of 16.8% in substrate configuration, and demonstrate 22.7% tandem efficiency with 3.3% absolute gain when mechanically stacked on a Cu(In,Ga)Se2 bottom cell. Non‐encapsulated graded perovskite device retains over 93% of its initial efficiency after 1000 h operation at maximum power point at 60 °C under equivalent 1 sun illumination. The results open an avenue in exploring partial ion‐exchange to design graded perovskite solar cells with improved efficiency and stability. PMID:29593970

  10. A Mini Review: Can Graphene Be a Novel Material for Perovskite Solar Cell Applications?

    Science.gov (United States)

    Lim, Eng Liang; Yap, Chi Chin; Jumali, Mohammad Hafizuddin Hj; Teridi, Mohd Asri Mat; Teh, Chin Hoong

    2018-06-01

    Perovskite solar cells (PSCs) have raised research interest in scientific community because their power conversion efficiency is comparable to that of traditional commercial solar cells (i.e., amorphous Si, GaAs, and CdTe). Apart from that, PSCs are lightweight, are flexible, and have low production costs. Recently, graphene has been used as a novel material for PSC applications due to its excellent optical, electrical, and mechanical properties. The hydrophobic nature of graphene surface can provide protection against air moisture from the surrounding medium, which can improve the lifetime of devices. Herein, we review recent developments in the use of graphene for PSC applications as a conductive electrode, carrier transporting material, and stabilizer material. By exploring the application of graphene in PSCs, a new class of strategies can be developed to improve the device performance and stability before it can be commercialized in the photovoltaic market in the near future.

  11. Compound polycrystalline solar cells. Recent progress and Y2K perspective

    Energy Technology Data Exchange (ETDEWEB)

    Birkmire, R.W. [Institute of Energy Conversion, University of Delaware, DE 19716 Newark (United States)

    2001-01-01

    A historical perspective on the development of polycrystalline thin-film solar cells based on CdTe and CuInSe{sub 2} is presented, and recent progress of these thin-film technologies is discussed. Impressive improvements in the efficiency of laboratory scale devices has not been easy to translate to the manufacturing environment, principally due to our lack of understanding of the basic science and engineering of these materials and devices. 'Next-generation' high-performance thin-film solar cells utilizing multijunction device configurations should achieve efficiencies of more than 25% within ten years. However, our cost-effective manufacturing of these more complex devices will be problematic unless the science and engineering issues associated with processing of thin-film PV devices are addressed.

  12. Structural and optoelectronic properties of β-In{sub 2}S{sub 3} thin films to Be applied on cadmium reduced solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Galarza Gutierrez, Uziel; Albor Aguilera, Maria Lourdes de; Hernandez Vasquez, Cesar; Aguilar Hernandez, Jorge R.; Remolina Millan, Aduljay [Instituto Politecnico Nacional - ESFM, Dept. de Fisica, U.P.A.L.M., Zacatenco (Mexico); Flores Marquez, Jose M. [Instituto Politecnico Nacional - ESIQIE, Dept. Metalurgia y Mat., U.P.A.L.M., Zacatenco (Mexico); Gonzalez Trujillo, Miguel A. [Instituto Politecnico Nacional - ESCOM, Dept. de Ciencias Basicas, U.P.A.L.M., Zacatenco (Mexico); Jimenez Olarte, Daniel [Instituto Politecnico Nacional - ESIME, SEPI, U.P.A.L.M., Zacatenco (Mexico)

    2018-02-15

    In{sub 2}S{sub 3} thin films are prepared by chemical bath deposition (CBD) technique to be applied as buffer layer in CdTe solar cells. CdTe photovoltaic devices are developed using In{sub 2}S{sub 3} as ''standard buffer layer'' in order to reduce the CdS thickness used as window material. It is important to examine potential thin films in a prospective life cycle study, focusing on direct costs, resource availability, and environmental impacts. Open and closed CBD system influence on the In{sub 2}S{sub 3} physical properties is analyzed. Stable tetragonal β-In{sub 2}S{sub 3} phase was confirmed by X-ray diffraction. Electrical properties were determined by four-point probe technique obtaining a resistivity value of 10{sup 2} Ω cm. CdTe solar cells performance was studied by measuring J-V characteristics and spectral quantum efficiencies. These results reveal In{sub 2}S{sub 3} thin films as buffer layer reduce the cadmium quantity used in solar cells manufacture and improve their current collection in blue wavelength region (300-500 nm). (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Development of Inorganic Solar Cells by Nanotechnology

    Institute of Scientific and Technical Information of China (English)

    Yafei Zhang; Huijuan Geng; Zhihua Zhou; Jiang Wu; Zhiming Wang; Yaozhong Zhang; Zhongli Li; Liying Zhang; Zhi Yang; Huey Liang Hwang

    2012-01-01

    Inorganic solar cells, as durable photovoltaic devices for harvesting electric energy from sun light,have received tremendous attention due to the fear of exhausting the earth’s energy resources and damaging the living environment due to greenhouse gases. Some recent developments in nanotechnology have opened up new avenues for more relevant inorganic solar cells produced by new photovoltaic conversion concepts and effective solar energy harvesting nanostructures. In this review, the multiple exciton generation effect solar cells, hot carrier solar cells, one dimensional material constructed asymmetrical schottky barrier arrays, noble nanoparticle induced plasmonic enhancement, and light trapping nanostructured semiconductor solar cells are highlighted.

  14. Embedded vertically aligned cadmium telluride nanorod arrays grown by one-step electrodeposition for enhanced energy conversion efficiency in three-dimensional nanostructured solar cells.

    Science.gov (United States)

    Wang, Jun; Liu, Shurong; Mu, Yannan; Liu, Li; A, Runa; Yang, Jiandong; Zhu, Guijie; Meng, Xianwei; Fu, Wuyou; Yang, Haibin

    2017-11-01

    Vertically aligned CdTe nanorods (NRs) arrays are successfully grown by a simple one-step and template-free electrodeposition method, and then embedded in the CdS window layer to form a novel three-dimensional (3D) heterostructure on flexible substrates. The parameters of electrodeposition such as deposition potential and pH of the solution are varied to analyze their important role in the formation of high quality CdTe NRs arrays. The photovoltaic conversion efficiency of the solar cell based on the 3D heterojunction structure is studied in detail. In comparison with the standard planar heterojunction solar cell, the 3D heterojunction solar cell exhibits better photovoltaic performance, which can be attributed to its enhanced optical absorption ability, increased heterojunction area and improved charge carrier transport. The better photoelectric property of the 3D heterojunction solar cell suggests great application potential in thin film solar cells, and the simple electrodeposition process represents a promising technique for large-scale fabrication of other nanostructured solar energy conversion devices. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Neutral Color Semitransparent Microstructured Perovskite Solar Cells

    KAUST Repository

    Eperon, Giles E.; Burlakov, Victor M.; Goriely, Alain; Snaith, Henry J.

    2014-01-01

    Neutral-colored semitransparent solar cells are commercially desired to integrate solar cells into the windows and cladding of buildings and automotive applications. Here, we report the use of morphological control of perovskite thin films to form

  16. Atomic-resolution characterization of the effects of CdCl2 treatment on poly-crystalline CdTe thin films

    Science.gov (United States)

    Paulauskas, T.; Buurma, C.; Colegrove, E.; Guo, Z.; Sivananthan, S.; Chan, M. K. Y.; Klie, R. F.

    2014-08-01

    Poly-crystalline CdTe thin films on glass are used in commercial solar-cell superstrate devices. It is well known that post-deposition annealing of the CdTe thin films in a CdCl2 environment significantly increases the device performance, but a fundamental understanding of the effects of such annealing has not been achieved. In this Letter, we report a change in the stoichiometry across twin boundaries in CdTe and propose that native point defects alone cannot account for this variation. Upon annealing in CdCl2, we find that the stoichiometry is restored. Our experimental measurements using atomic-resolution high-angle annular dark field imaging, electron energy-loss spectroscopy, and energy dispersive X-ray spectroscopy in a scanning transmission electron microscope are supported by first-principles density functional theory calculations.

  17. Organic and hybrid solar cells

    CERN Document Server

    Huang, Hui

    2014-01-01

    This book delivers a comprehensive evaluation of organic and hybrid solar cells and identifies their fundamental principles and numerous applications. Great attention is given to the charge transport mechanism, donor and acceptor materials, interfacial materials, alternative electrodes, device engineering and physics, and device stability. The authors provide an industrial perspective on the future of photovoltaic technologies.

  18. Plastic solar cells

    International Nuclear Information System (INIS)

    Brabec, C.J.; Sariciftci, N.S.; Hummelen, J.C.

    2001-01-01

    Recent developments in conjugated-polymer-based photovoltaic elements are reviewed. The photophysics of such photoactive devices is based on the photo-induced charge transfer from donor-type semiconducting conjugated polymers to acceptor-type conjugated polymers or acceptor molecules such as Buckminsterfullerene, C 60 . This photo-induced charge transfer is reversible, ultrafast (within 100 fs) with a quantum efficiency approaching unity, and the charge-separated state is metastable (up to milliseconds at 80 K). Being similar to the first steps in natural photosynthesis, this photo-induced electron transfer leads to a number of potentially interesting applications, which include sensitization of the photoconductivity and photovoltaic phenomena. Examples of photovoltaic architectures are presented and their potential in terrestrial solar energy conversion discussed. Recent progress in the realization of improved photovoltaic elements with 3% power conversion efficiency is reported. (orig.)

  19. Surface Passivation for Silicon Heterojunction Solar Cells

    NARCIS (Netherlands)

    Deligiannis, D.

    2017-01-01

    Silicon heterojunction solar cells (SHJ) are currently one of the most promising solar cell technologies in the world. The SHJ solar cell is based on a crystalline silicon (c-Si) wafer, passivated on both sides with a thin intrinsic hydrogenated amorphous silicon (a-Si:H) layer. Subsequently, p-type

  20. Challenges in amorphous silicon solar cell technology

    NARCIS (Netherlands)

    Swaaij, van R.A.C.M.M.; Zeman, M.; Korevaar, B.A.; Smit, C.; Metselaar, J.W.; Sanden, van de M.C.M.

    2000-01-01

    Hydrogenated amorphous silicon is nowadays extensively used for a range of devices, amongst others solar cells, Solar cell technology has matured over the last two decades and resulted in conversion efficiencies in excess of 15%. In this paper the operation of amorphous silicon solar cells is

  1. Microstructure of absorber layers in CdTe/CdS solar cells

    International Nuclear Information System (INIS)

    Cousins, M.A.

    2001-04-01

    This work concerns the microstructure of CSS-grown CdTe layers used for CdTe/CdS solar cells. Particular attention is given to how the development of microstructure on annealing with CdCl 2 may correlate with increases in efficiency. By annealing pressed pellets of bulk CdTe powder, it is shown that microstructural change does occur on heating the material, enhanced by the inclusion of CdCl 2 flux. However, the temperature required to cause significant effects is demonstrated to be higher than that at which heavy oxidation takes place. The dynamics of this oxidation are also examined. To investigate microstructural evolution in thin-films of CdTe, bi-layers of CdTe and CdS are examined by bevelling, thus revealing the microstructure to within ∼1 μm of the interface. This allows optical microscopy and subsequent image analysis of grain structure. The work shows that the grain-size, which is well described by the Rayleigh distribution, varies linearly throughout the layer, but is invariant under CdCl 2 treatment. Electrical measurements on these bi-layers, however, showed increased efficiency, as is widely reported. This demonstrates that the efficiency of these devices is not dictated by the bulk microstructure. Further, the region within 1 μm of the interface, of similar bi-layers to above, is examined by plan-view TEM. This reveals five-fold grain-growth on CdCl 2 treatment. Moreover, these grains show a considerably smaller grain size than expected from extrapolating the linear trend in the bulk. These observations are explained in terms of the pinning of the CdTe grain size to the underlying CdS, and the small grain size this causes. A simple model was proposed for a link between the grain-growth to the efficiency improvement. The study also examines the behaviour of defects within grains upon CdCl 2 treatment provided the first direct evidence of recovery on CdCl 2 treatment in this system. Finally, a computer model is presented to describe the evolution of

  2. Hybrid emitter all back contact solar cell

    Science.gov (United States)

    Loscutoff, Paul; Rim, Seung

    2016-04-12

    An all back contact solar cell has a hybrid emitter design. The solar cell has a thin dielectric layer formed on a backside surface of a single crystalline silicon substrate. One emitter of the solar cell is made of doped polycrystalline silicon that is formed on the thin dielectric layer. The other emitter of the solar cell is formed in the single crystalline silicon substrate and is made of doped single crystalline silicon. The solar cell includes contact holes that allow metal contacts to connect to corresponding emitters.

  3. Development of Deposition and Characterization Systems for Thin Film Solar Cells

    Science.gov (United States)

    Cimaroli, Alexander J.

    Photovoltaic (PV) devices are becoming more important due to a number of economic and environmental factors. PV research relies on the ability to quickly fabricate and characterize these devices. While there are a number of deposition methods that are available in a laboratory setting, they are not necessarily able to be scaled to provide high throughput in a commercial setting. A close-space sublimation (CSS) system was developed to provide a means of depositing thin films in a very controlled and scalable manner. Its viability was explored by using it to deposit the absorber layer in Zn3P2 and CdTe solar cell devices. Excellent control over morphology and growth conditions and a high level of repeatability was demonstrated in the study of textured Zn3P2 thin films. However, some limitations imposed by the structure of Zn3P 2-based PV devices showed that CSS may not be the best approach for depositing Zn3P2 thin films. Despite the inability to make Zn3P2 solar cell devices, high efficiency CdTe solar cells were fabricated using CSS. With the introduction of Perovskite-based solar cell devices, the viability of data collected from conventional J-V measurements was questioned due to the J-V hysteresis that Perovskite devices exhibited. New methods of solar cell characterization were developed in order to accurately and quickly assess the performance of hysteretic PV devices. Both J-V measurements and steady-state efficiency measurements are prone to errors due to hysteresis and maximum power point drift. To resolve both of these issues, a maximum power point tracking (MPPT) system was developed with two algorithms: a simple algorithm and a predictive algorithm. The predictive algorithm showed increased resistance to the effects of hysteresis because of its ability to predict the steady-state current after a bias step with a double exponential decay model fit. Some publications have attempted to quantify the degree of J-V hysteresis present in fabricated Perovskite

  4. Three-Terminal Amorphous Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Cheng-Hung Tai

    2011-01-01

    Full Text Available Many defects exist within amorphous silicon since it is not crystalline. This provides recombination centers, thus reducing the efficiency of a typical a-Si solar cell. A new structure is presented in this paper: a three-terminal a-Si solar cell. The new back-to-back p-i-n/n-i-p structure increased the average electric field in a solar cell. A typical a-Si p-i-n solar cell was also simulated for comparison using the same thickness and material parameters. The 0.28 μm-thick three-terminal a-Si solar cell achieved an efficiency of 11.4%, while the efficiency of a typical a-Si p-i-n solar cell was 9.0%. Furthermore, an efficiency of 11.7% was achieved by thickness optimization of the three-terminal solar cell.

  5. Translocation and neurotoxicity of CdTe quantum dots in RMEs motor neurons in nematode Caenorhabditis elegans

    International Nuclear Information System (INIS)

    Zhao, Yunli; Wang, Xiong; Wu, Qiuli; Li, Yiping; Wang, Dayong

    2015-01-01

    Graphical abstract: - Highlights: • We investigated in vivo neurotoxicity of CdTe QDs on RMEs motor neurons in C. elegans. • CdTe QDs in the range of μg/L caused neurotoxicity on RMEs motor neurons. • Bioavailability of CdTe QDs may be the primary inducer for CdTe QDs neurotoxicity. • Both oxidative stress and cell identity regulate the CdTe QDs neurotoxicity. • CdTe QDs were translocated and deposited into RMEs motor neurons. - Abstract: We employed Caenorhabditis elegans assay system to investigate in vivo neurotoxicity of CdTe quantum dots (QDs) on RMEs motor neurons, which are involved in controlling foraging behavior, and the underlying mechanism of such neurotoxicity. After prolonged exposure to 0.1–1 μg/L of CdTe QDs, abnormal foraging behavior and deficits in development of RMEs motor neurons were observed. The observed neurotoxicity from CdTe QDs on RMEs motor neurons might be not due to released Cd 2+ . Overexpression of genes encoding Mn-SODs or unc-30 gene controlling cell identity of RMEs neurons prevented neurotoxic effects of CdTe QDs on RMEs motor neurons, suggesting the crucial roles of oxidative stress and cell identity in regulating CdTe QDs neurotoxicity. In nematodes, CdTe QDs could be translocated through intestinal barrier and be deposited in RMEs motor neurons. In contrast, CdTe@ZnS QDs could not be translocated into RMEs motor neurons and therefore, could only moderately accumulated in intestinal cells, suggesting that ZnS coating might reduce neurotoxicity of CdTe QDs on RMEs motor neurons. Therefore, the combinational effects of oxidative stress, cell identity, and bioavailability may contribute greatly to the mechanism of CdTe QDs neurotoxicity on RMEs motor neurons. Our results provide insights into understanding the potential risks of CdTe QDs on the development and function of nervous systems in animals

  6. Translocation and neurotoxicity of CdTe quantum dots in RMEs motor neurons in nematode Caenorhabditis elegans

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yunli; Wang, Xiong; Wu, Qiuli; Li, Yiping; Wang, Dayong, E-mail: dayongw@seu.edu.cn

    2015-02-11

    Graphical abstract: - Highlights: • We investigated in vivo neurotoxicity of CdTe QDs on RMEs motor neurons in C. elegans. • CdTe QDs in the range of μg/L caused neurotoxicity on RMEs motor neurons. • Bioavailability of CdTe QDs may be the primary inducer for CdTe QDs neurotoxicity. • Both oxidative stress and cell identity regulate the CdTe QDs neurotoxicity. • CdTe QDs were translocated and deposited into RMEs motor neurons. - Abstract: We employed Caenorhabditis elegans assay system to investigate in vivo neurotoxicity of CdTe quantum dots (QDs) on RMEs motor neurons, which are involved in controlling foraging behavior, and the underlying mechanism of such neurotoxicity. After prolonged exposure to 0.1–1 μg/L of CdTe QDs, abnormal foraging behavior and deficits in development of RMEs motor neurons were observed. The observed neurotoxicity from CdTe QDs on RMEs motor neurons might be not due to released Cd{sup 2+}. Overexpression of genes encoding Mn-SODs or unc-30 gene controlling cell identity of RMEs neurons prevented neurotoxic effects of CdTe QDs on RMEs motor neurons, suggesting the crucial roles of oxidative stress and cell identity in regulating CdTe QDs neurotoxicity. In nematodes, CdTe QDs could be translocated through intestinal barrier and be deposited in RMEs motor neurons. In contrast, CdTe@ZnS QDs could not be translocated into RMEs motor neurons and therefore, could only moderately accumulated in intestinal cells, suggesting that ZnS coating might reduce neurotoxicity of CdTe QDs on RMEs motor neurons. Therefore, the combinational effects of oxidative stress, cell identity, and bioavailability may contribute greatly to the mechanism of CdTe QDs neurotoxicity on RMEs motor neurons. Our results provide insights into understanding the potential risks of CdTe QDs on the development and function of nervous systems in animals.

  7. Work Station For Inverting Solar Cells

    Science.gov (United States)

    Feder, H.; Frasch, W.

    1982-01-01

    Final work station along walking-beam conveyor of solar-array assembly line turns each pretabbed solar cell over, depositing it back-side-up onto landing pad, which centers cell without engaging collector surface. Solar cell arrives at inverting work station collector-side-up with two interconnect tabs attached to collector side. Cells are inverted so that second soldering operation takes place in plain view of operator. Inversion protects collector from damage when handled at later stages of assembly.

  8. Extended Temperature Solar Cell Technology Development

    Science.gov (United States)

    Landis, Geoffrey A.; Jenkins, Phillip; Scheiman, David; Rafaelle, Ryne

    2004-01-01

    Future NASA missions will require solar cells to operate both in regimes closer to the sun, and farther from the sun, where the operating temperatures will be higher and lower than standard operational conditions. NASA Glenn is engaged in testing solar cells under extended temperature ranges, developing theoretical models of cell operation as a function of temperature, and in developing technology for improving the performance of solar cells for both high and low temperature operation.

  9. Hybrid Perovskites: Prospects for Concentrator Solar Cells.

    Science.gov (United States)

    Lin, Qianqian; Wang, Zhiping; Snaith, Henry J; Johnston, Michael B; Herz, Laura M

    2018-04-01

    Perovskite solar cells have shown a meteoric rise of power conversion efficiency and a steady pace of improvements in their stability of operation. Such rapid progress has triggered research into approaches that can boost efficiencies beyond the Shockley-Queisser limit stipulated for a single-junction cell under normal solar illumination conditions. The tandem solar cell architecture is one concept here that has recently been successfully implemented. However, the approach of solar concentration has not been sufficiently explored so far for perovskite photovoltaics, despite its frequent use in the area of inorganic semiconductor solar cells. Here, the prospects of hybrid perovskites are assessed for use in concentrator solar cells. Solar cell performance parameters are theoretically predicted as a function of solar concentration levels, based on representative assumptions of charge-carrier recombination and extraction rates in the device. It is demonstrated that perovskite solar cells can fundamentally exhibit appreciably higher energy-conversion efficiencies under solar concentration, where they are able to exceed the Shockley-Queisser limit and exhibit strongly elevated open-circuit voltages. It is therefore concluded that sufficient material and device stability under increased illumination levels will be the only significant challenge to perovskite concentrator solar cell applications.

  10. Thermochromic halide perovskite solar cells

    Science.gov (United States)

    Lin, Jia; Lai, Minliang; Dou, Letian; Kley, Christopher S.; Chen, Hong; Peng, Fei; Sun, Junliang; Lu, Dylan; Hawks, Steven A.; Xie, Chenlu; Cui, Fan; Alivisatos, A. Paul; Limmer, David T.; Yang, Peidong

    2018-03-01

    Smart photovoltaic windows represent a promising green technology featuring tunable transparency and electrical power generation under external stimuli to control the light transmission and manage the solar energy. Here, we demonstrate a thermochromic solar cell for smart photovoltaic window applications utilizing the structural phase transitions in inorganic halide perovskite caesium lead iodide/bromide. The solar cells undergo thermally-driven, moisture-mediated reversible transitions between a transparent non-perovskite phase (81.7% visible transparency) with low power output and a deeply coloured perovskite phase (35.4% visible transparency) with high power output. The inorganic perovskites exhibit tunable colours and transparencies, a peak device efficiency above 7%, and a phase transition temperature as low as 105 °C. We demonstrate excellent device stability over repeated phase transition cycles without colour fade or performance degradation. The photovoltaic windows showing both photoactivity and thermochromic features represent key stepping-stones for integration with buildings, automobiles, information displays, and potentially many other technologies.

  11. Thermochromic halide perovskite solar cells.

    Science.gov (United States)

    Lin, Jia; Lai, Minliang; Dou, Letian; Kley, Christopher S; Chen, Hong; Peng, Fei; Sun, Junliang; Lu, Dylan; Hawks, Steven A; Xie, Chenlu; Cui, Fan; Alivisatos, A Paul; Limmer, David T; Yang, Peidong

    2018-03-01

    Smart photovoltaic windows represent a promising green technology featuring tunable transparency and electrical power generation under external stimuli to control the light transmission and manage the solar energy. Here, we demonstrate a thermochromic solar cell for smart photovoltaic window applications utilizing the structural phase transitions in inorganic halide perovskite caesium lead iodide/bromide. The solar cells undergo thermally-driven, moisture-mediated reversible transitions between a transparent non-perovskite phase (81.7% visible transparency) with low power output and a deeply coloured perovskite phase (35.4% visible transparency) with high power output. The inorganic perovskites exhibit tunable colours and transparencies, a peak device efficiency above 7%, and a phase transition temperature as low as 105 °C. We demonstrate excellent device stability over repeated phase transition cycles without colour fade or performance degradation. The photovoltaic windows showing both photoactivity and thermochromic features represent key stepping-stones for integration with buildings, automobiles, information displays, and potentially many other technologies.

  12. Semiconductor materials for solar photovoltaic cells

    CERN Document Server

    Wong-Ng, Winnie; Bhattacharya, Raghu

    2016-01-01

    This book reviews the current status of semiconductor materials for conversion of sunlight to electricity, and highlights advances in both basic science and manufacturing.  Photovoltaic (PV) solar electric technology will be a significant contributor to world energy supplies when reliable, efficient PV power products are manufactured in large volumes at low cost.  Expert chapters cover the full range of semiconductor materials for solar-to-electricity conversion, from crystalline silicon and amorphous silicon to cadmium telluride, copper indium gallium sulfide selenides, dye sensitized solar cells, organic solar cells, and environmentally friendly copper zinc tin sulfide selenides. The latest methods for synthesis and characterization of solar cell materials are described, together with techniques for measuring solar cell efficiency. Semiconductor Materials for Solar Photovoltaic Cells presents the current state of the art as well as key details about future strategies to increase the efficiency and reduce ...

  13. Nanostructures for Organic Solar Cells

    DEFF Research Database (Denmark)

    Goszczak, Arkadiusz Jarosław

    2016-01-01

    The experimental work in this thesis is focused on the fabrication of nanostructures that can be implemented in organic solar cell (OSC) architecture for enhancement of the device performance. Solar devices made from organic material are gaining increased attention, compared to their inorganic...... counterparts, due to the promising advantages, such as transparency, flexibility, ease of processing etc. But their efficiencies cannot be compared to the inorganic ones. Boosting the efficiency of OSCs by nanopatterning has thus been puzzling many researchers within the past years. Therefore various methods...... have been proposed to be used for developing efficient nanostructures for OSC devices such as, plasmonic structures, nanowires (NWs), gratings, nanorods etc. The nanostructuring methods applied though, do not offer the possibility of a cheap, rapid, reproducible and scalable fabrication. It is the aim...

  14. Dye solar cells: a different approach to solar energy

    CSIR Research Space (South Africa)

    Le Roux, Lukas J

    2008-11-01

    Full Text Available An attractive and cheaper alternative to siliconbased photovoltaic (PV) cells for the conversion of solar light into electrical energy is to utilise dyeadsorbed, large-band-gap metal oxide materials such as TiO2 to absorb the solar light...

  15. Quantum Dots for Solar Cell Application

    Science.gov (United States)

    Poudyal, Uma

    Solar energy has been anticipated as the most important and reliable source of renewable energy to address the ever-increasing energy demand. To harvest solar energy efficiently, diverse kinds of solar cells have been studied. Among these, quantum dot sensitized solar cells have been an interesting group of solar cells mainly due to tunable, size-dependent electronic and optical properties of quantum dots. Moreover, doping these quantum dots with transition metal elements such as Mn opens avenue for improved performance of solar cells as well as for spin based technologies. In this dissertation, Mn-doped CdSe QDs (Mn-CdSe) have been synthesized by Successive Ionic Layer Adsorption and Reaction (SILAR) method. They are used in solar cells to study the effect of Mn doping in the performance of solar cells. Incident photon to current-conversion efficiency (IPCE) is used to record the effect of Mn-doping. Intensity modulated photovoltage and photocurrent spectroscopy (IMVS/PS) has been used to study the carrier dynamics in these solar cells. Additionally, the magnetic properties of Mn-CdSe QDs is studied and its possible origin is discussed. Moreover, CdS/CdSe QDs have been used to study the effect of liquid, gel and solid electrolyte in the performance and stability of the solar cells. Using IPCE spectra, the time decay measurements are presented and the possible reactions between the QD and the electrolytes are explained.

  16. Reduction of Fermi level pinning and recombination at polycrystalline CdTe surfaces by laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Simonds, Brian J. [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Kheraj, Vipul [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Department of Applied Physics, S. V. National Institute of Technology, Surat 395 007 (India); Palekis, Vasilios; Ferekides, Christos [Electrical Engineering, University of South Florida, Tampa, Florida 33620 (United States); Scarpulla, Michael A., E-mail: scarpulla@eng.utah.edu [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112 (United States)

    2015-06-14

    Laser processing of polycrystalline CdTe is a promising approach that could potentially increase module manufacturing throughput while reducing capital expenditure costs. For these benefits to be realized, the basic effects of laser irradiation on CdTe must be ascertained. In this study, we utilize surface photovoltage spectroscopy (SPS) to investigate the changes to the electronic properties of the surface of polycrystalline CdTe solar cell stacks induced by continuous-wave laser annealing. The experimental data explained within a model consisting of two space charge regions, one at the CdTe/air interface and one at the CdTe/CdS junction, are used to interpret our SPS results. The frequency dependence and phase spectra of the SPS signal are also discussed. To support the SPS findings, low-temperature spectrally-resolved photoluminescence and time-resolved photoluminescence were also measured. The data show that a modest laser treatment of 250 W/cm{sup 2} with a dwell time of 20 s is sufficient to reduce the effects of Fermi level pinning at the surface due to surface defects.

  17. First-principles-based analysis of the influence of Cu on CdTe electronic properties

    International Nuclear Information System (INIS)

    Krasikov, D.; Knizhnik, A.; Potapkin, B.; Selezneva, S.; Sommerer, T.

    2013-01-01

    The maximum voltage of CdTe solar cells is limited by low majority carrier concentration and doping difficulty. Copper that enters from the back contact can form both donors and acceptors in CdTe. It is empirically known that the free carrier concentration is several orders lower than the total Cu concentration. Simplified thermodynamic models of defect compensation after Cu introduction can be found in literature. We present a first-principles-based analysis of kinetics of defect formation upon Cu introduction, and show that Cu i is mobile at room temperature. Calculations of properties of Cu i –V Cd and Cu i –Cu Cd complexes show that the neutral Cu i –Cu Cd complex is mobile at elevated temperatures, while formation of the V Cd –Cu i complex is unlikely because it transforms into the Cu Cd defect. - Highlights: ► First-principles calculations of copper defects in CdTe are performed. ► Formation of Cd vacancy + Cu interstitial(Cu i ) complex is unlikely. ► Cu i defect is mobile at room temperature. ► Cu i + Cu on Cd-site (Cu Cd ) complex is mobile at elevated temperature. ► Cu Cd defect forms by kicking-out of the regular lattice Cd by Cu i

  18. Unconventional device concepts for polymer solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Veenstra, S.C.; Slooff, L.H.; Verhees, W.J.H.; Cobussen-Pool, E.M.; Lenzmann, F.O.; Kroon, J.M. [ECN Solar Energy, Petten (Netherlands); Sessolo, M.; Bolink, H.J. [Instituto de Ciencia Molecular, Universidad de Valencia, Valencia (Spain)

    2009-09-15

    The inclusion of metal-oxide layers in polymer solar cells enables the fabrication of a series of unconventional device architectures. These devices include: semi-transparent polymer solar cells, devices with inverted polarity, as well as devices with air stable electrodes. A proof-of-principle of these devices is presented. The anticipated benefits of these novel device structures over conventional polymer solar cells are discussed.

  19. Device operation of organic tandem solar cells

    NARCIS (Netherlands)

    Hadipour, A.; de Boer, B.; Blom, P. W. M.

    2008-01-01

    A generalized methodology is developed to obtain the current-voltage characteristic of polymer tandem solar cells by knowing the electrical performance of both sub cells. We demonstrate that the electrical characteristics of polymer tandem solar cells are correctly predicted for both the series and

  20. Solar Cells Using Quantum Funnels

    KAUST Repository

    Kramer, Illan J.

    2011-09-14

    Colloidal quantum dots offer broad tuning of semiconductor bandstructure via the quantum size effect. Devices involving a sequence of layers comprised of quantum dots selected to have different diameters, and therefore bandgaps, offer the possibility of funneling energy toward an acceptor. Here we report a quantum funnel that efficiently conveys photoelectrons from their point of generation toward an intended electron acceptor. Using this concept we build a solar cell that benefits from enhanced fill factor as a result of this quantum funnel. This concept addresses limitations on transport in soft condensed matter systems and leverages their advantages in large-area optoelectronic devices and systems. © 2011 American Chemical Society.

  1. Integration of Solar Cells on Top of CMOS Chips - Part II: CIGS Solar Cells

    NARCIS (Netherlands)

    Lu, J.; Liu, Wei; Kovalgin, Alexeij Y.; Sun, Yun; Schmitz, Jurriaan

    2011-01-01

    We present the monolithic integration of deepsubmicrometer complementary metal–oxide–semiconductor (CMOS) microchips with copper indium gallium (di)selenide (CIGS) solar cells. Solar cells are manufactured directly on unpackaged CMOS chips. The microchips maintain comparable electronic performance,

  2. Machine for welding solar cell connections

    Energy Technology Data Exchange (ETDEWEB)

    Lorans, D.Y.

    1977-08-09

    A machine for welding a connection wire over a solar cell electrode is described which comprises a base, a welding mount for the solar cell which is supported on the base, means for holding the solar cell on the welding mount, welding electrodes, means to lower the welding electrodes over the solar cell and the connection wire superimposed thereon, means for applying electric current pulses to said welding electrodes. It is characterized by the fact that it further comprises means for imparting to said mount an alternating transverse movement in relation to said base before and during the welding operation.

  3. Theoretical investigation on heterojunction solar cell

    International Nuclear Information System (INIS)

    Prema, K.; Geetha, K.

    1986-11-01

    The study of thin film solar cells has proved that the surface is rough. A two-dimensional method based on the integral equation technique to analyse thin film solar cells has been developed by DeMey et al. In this paper we present our analysis of a thin film solar cell using the above techniques. Variation of the minority carrier concentration, the saturation current and the junction current of the solar cell with surface roughness is presented. (author). 8 refs, 4 figs

  4. Integration of Solar Cells on Top of CMOS Chips Part I: a-Si Solar Cells

    NARCIS (Netherlands)

    Lu, J.; Kovalgin, Alexeij Y.; van der Werf, Karine H.M.; Schropp, Ruud E.I.; Schmitz, Jurriaan

    2011-01-01

    We present the monolithic integration of deepsubmicrometer complementary metal–oxide–semiconductor (CMOS) microchips with a-Si:H solar cells. Solar cells are manufactured directly on the CMOS chips. The microchips maintain comparable electronic performance, and the solar cells show efficiency values

  5. Multi-Material Front Contact for 19% Thin Film Solar Cells

    Directory of Open Access Journals (Sweden)

    Joop van Deelen

    2016-02-01

    Full Text Available The trade-off between transmittance and conductivity of the front contact material poses a bottleneck for thin film solar panels. Normally, the front contact material is a metal oxide and the optimal cell configuration and panel efficiency were determined for various band gap materials, representing Cu(In,GaSe2 (CIGS, CdTe and high band gap perovskites. Supplementing the metal oxide with a metallic copper grid improves the performance of the front contact and aims to increase the efficiency. Various front contact designs with and without a metallic finger grid were calculated with a variation of the transparent conductive oxide (TCO sheet resistance, scribing area, cell length, and finger dimensions. In addition, the contact resistance and illumination power were also assessed and the optimal thin film solar panel design was determined. Adding a metallic finger grid on a TCO gives a higher solar cell efficiency and this also enables longer cell lengths. However, contact resistance between the metal and the TCO material can reduce the efficiency benefit somewhat.

  6. Influences of the CdS nanoparticles grown strategies on CdTe nanorods array films: A comparison between successive ionic layer absorption and reaction and chemical bath deposition

    International Nuclear Information System (INIS)

    Wang, Jun; Zhou, Xiaoming; Lv, Pin; Yang, Lihua; Ding, Dong; Niu, Jiasheng; Liu, Li; Li, Xue; Fu, Wuyou; Yang, Haibin

    2016-01-01

    The cadmium sulfide (CdS) film is deposited on the surface of cadmium telluride (CdTe) nanorods (NRs) by two different methods, successive ionic layer adsorption and reaction (SILAR) and chemical bath deposition (CBD) techniques. The influence of the deposition parameters on the properties of the films is investigated. Compared to SILAR, CBD is a simple and time saving technique, which can ensure full coverage and better growth of CdS on the surface of CdTe NRs. The photovoltaic characteristics of CdS sensitized CdTe films are also investigated. It is found that the CdTe/CBD-CdS thin film demonstrates excellent photoelectrical properties, which is ascribed to the large absorption coefficient of the material, indicating the potential applications in solar cells.

  7. Superior light trapping in thin film silicon solar cells through nano imprint lithography

    Energy Technology Data Exchange (ETDEWEB)

    Soppe, W.J.; Dorenkamper, M.S.; Schropp, R.E.I.; Pex, P.P.A.C.

    2013-10-15

    ECN and partners have developed a fabrication process based on nanoimprint lithography (NIL) of textures for light trapping in thin film solar cells such as thin-film silicon, OPV, CIGS and CdTe. The process can be applied in roll-to-roll mode when using a foil substrate or in roll-to-plate mode when using a glass substrate. The lacquer also serves as an electrically insulating layer for cells if steel foil is used as substrate, to enable monolithic series interconnection. In this paper we will show the superior light trapping in thin film silicon solar cells made on steel foil with nanotextured back contacts. We have made single junction a-Si and {mu}c-Si and a-Si/{mu}c-Si tandem cells, where we applied several types of nano-imprints with random and periodic structures. We will show that the nano-imprinted back contact enables more than 30% increase of current in comparison with non-textured back contacts and that optimized periodic textures outperform state-of-the-art random textures. For a-Si cells we obtained Jsc of 18 mA/cm{sup 2} and for {mu}c-Si cells more than 24 mA/cm{sup 2}. Tandem cells with a total Si absorber layer thickness of only 1350 nm have an initial efficiency of 11%.

  8. Scaling up ITO-Free solar cells

    NARCIS (Netherlands)

    Galagan, Y.O.; Coenen, E.W.C.; Zimmermann, B.; Slooff, L.H.; Verhees, W.J.H.; Veenstra, S.C.; Kroon, J.M.; Jørgensen, M.; Krebs, F.C.; Andriessen, H.A.J.M.

    2014-01-01

    Indium-tin-oxide-free (ITO-free) polymer solar cells with composite electrodes containing current-collecting grids and a semitransparent poly(3,4-ethylenedioxythiophene):polystyrenesulfonate) (PEDOT:PSS) conductor are demonstrated. The up-scaling of the length of the solar cell from 1 to 6 cm and

  9. Dye-sensitised solar cell (artificial photosynthesis)

    CSIR Research Space (South Africa)

    Le Roux, Lukas J

    2005-07-01

    Full Text Available A novel system that harnesses solar energy is the nano-crystalline TiO dye-sensitised solar cell (DSC), in conjunction with several new concepts, such as nanotechnology and molecular devices. An efficient and low-cost cell can be produced by using...

  10. Predicted solar cell edge radiation effects

    International Nuclear Information System (INIS)

    Gates, M.T.

    1993-01-01

    The Advanced Solar Cell Orbital Test (ASCOT) will test six types of solar cells in a high energy proton environment. During the design of the experiment a question was raised about the effects of proton radiation incident on the edge of the solar cells and whether edge radiation shielding was required. Historical geosynchronous data indicated that edge radiation damage is not detectable over the normal end of life solar cell degradation; however because the ASCOT radiation environment has a much higher and more energetic fluence of protons, considerably more edge damage is expected. A computer analysis of the problem was made by modeling the expected radiation damage at the cell edge and using a network model of small interconnected solar cells to predict degradation in the cell's electrical output. The model indicated that the deepest penetration of edge radiation was at the top of the cell near the junction where the protons have access to the cell through the low density cell/cover adhesive layer. The network model indicated that the cells could tolerate high fluences at their edge as long as there was high electrical resistance between the edge radiated region and the contact system on top of the cell. The predicted edge radiation related loss was less than 2% of maximum power for GaAs/Ge solar cells. As a result, no edge radiation protection was used for ASCOT

  11. Fullerene surfactants and their use in polymer solar cells

    Science.gov (United States)

    Jen, Kwan-Yue; Yip, Hin-Lap; Li, Chang-Zhi

    2015-12-15

    Fullerene surfactant compounds useful as interfacial layer in polymer solar cells to enhance solar cell efficiency. Polymer solar cell including a fullerene surfactant-containing interfacial layer intermediate cathode and active layer.

  12. Landfill waste and recycling: Use of a screening-level risk assessment tool for end-of-life cadmium telluride (CdTe) thin-film photovoltaic (PV) panels

    International Nuclear Information System (INIS)

    Cyrs, William D.; Avens, Heather J.; Capshaw, Zachary A.; Kingsbury, Robert A.; Sahmel, Jennifer; Tvermoes, Brooke E.

    2014-01-01

    Grid-connected solar photovoltaic (PV) power is currently one of the fastest growing power-generation technologies in the world. While PV technologies provide the environmental benefit of zero emissions during use, the use of heavy metals in thin-film PV cells raises important health and environmental concerns regarding the end-of-life disposal of PV panels. To date, there is no published quantitative assessment of the potential human health risk due to cadmium leaching from cadmium telluride (CdTe) PV panels disposed in a landfill. Thus, we used a screening-level risk assessment tool to estimate possible human health risk associated with disposal of CdTe panels into landfills. In addition, we conducted a literature review of potential cadmium release from the recycling process in order to contrast the potential health risks from PV panel disposal in landfills to those from PV panel recycling. Based on the results of our literature review, a meaningful risk comparison cannot be performed at this time. Based on the human health risk estimates generated for PV panel disposal, our assessment indicated that landfill disposal of CdTe panels does not pose a human health hazard at current production volumes, although our results pointed to the importance of CdTe PV panel end-of-life management. - Highlights: • Analysis of possible human health risk posed by disposal of CdTe panels into landfills. • Qualitative comparison of risks associated with landfill disposal and recycling of CdTe panels. • Landfill disposal of CdTe panels does not pose a human health hazard at current production volumes. • There could be potential risks associated with recycling if not properly managed. • Factors other than concerns over toxic substances will likely drive the decisions of how to manage end-of-life PV panels

  13. High Radiation Resistance IMM Solar Cell

    Science.gov (United States)

    Pan, Noren

    2015-01-01

    Due to high launch costs, weight reduction is a key driver for the development of new solar cell technologies suitable for space applications. This project is developing a unique triple-junction inverted metamorphic multijunction (IMM) technology that enables the manufacture of very lightweight, low-cost InGaAsP-based multijunction solar cells. This IMM technology consists of indium (In) and phosphorous (P) solar cell active materials, which are designed to improve the radiation-resistant properties of the triple-junction solar cell while maintaining high efficiency. The intrinsic radiation hardness of InP materials makes them of great interest for building solar cells suitable for deployment in harsh radiation environments, such as medium Earth orbit and missions to the outer planets. NASA Glenn's recently developed epitaxial lift-off (ELO) process also will be applied to this new structure, which will enable the fabrication of the IMM structure without the substrate.

  14. Organic Based Solar Cells with Morphology Control

    DEFF Research Database (Denmark)

    Andersen, Thomas Rieks

    The field of organic solar cells has in the last years gone through an impressive development with efficiencies reported up to 12 %. For organic solar cells to take the leap from primarily being a laboratory scale technology to being utilized as renewable energy source, several issues need...... Microscopy and as solar cells in a blend with PCBM. It was concluded that these particles did not show a potential large enough for continuous work due to a high material loss and low efficiency when applied in solar cells. The second method to achieve was preparation of pre-arranged morphology organic...... nanoparticles consisting of a blend of donor and acceptor in an aqueous dispersion, thereby addressing two of the issues remaining in the field of organic solar cells. This approach was used on six different polymers, which all had the ability to prepare aqueous nanoparticle inks. The morphology...

  15. Numerical study of the influence of ZnTe thickness on CdS/ZnTe solar cell performance

    Science.gov (United States)

    Skhouni, Othmane; El Manouni, Ahmed; Mari, Bernabe; Ullah, Hanif

    2016-05-01

    At present most of II-VI semiconductor based solar cells use the CdTe material as an absorber film. The simulation of its performance is realized by means of various numerical modelling programs. We have modelled a solar cell based on zinc telluride (ZnTe) thin film as absorber in substitution to the CdTe material, which contains the cadmium element known by its toxicity. The performance of such photovoltaic device has been numerically simulated and the thickness of the absorber layer has been optimized to give the optimal conversion efficiency. A photovoltaic device consisting of a ZnTe layer as absorber, CdS as the buffer layer and ZnO as a window layer was modelled through Solar Cell Capacitance Simulator Software. Dark and illuminated I-V characteristics and the results for different output parameters of ZnO/CdS/ZnTe solar cell were analyzed. The effect of ZnTe absorber thickness on different main working parameters such as: open-circuit voltage Voc, short-circuit current density Jsc, fill factor FF, photovoltaic conversion efficiency η was intensely studied in order to optimize ZnTe film thickness. This study reveals that increasing the thickness of ZnTe absorber layer results in higher efficiency until a maximum value and then decreases slightly. This maximum was found to be 10% at ZnTe optimum thickness close to 2 µm. Contribution to the topical issue "Materials for Energy Harvesting, Conversion and Storage (ICOME 2015) - Elected submissions", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

  16. Bonder for Solar-Cell Strings

    Science.gov (United States)

    Garwood, G.; Frasch, W.

    1982-01-01

    String bonder for solar-cell arrays eliminates tedious manual assembly procedure that could damage cell face. Vacuum arm picks up face-down cell from cell-inverting work station and transfers it to string conveyor without changing cell orientation. Arm is activated by signal from microprocessor.

  17. Tandem photovoltaic solar cells and increased solar energy conversion efficiency

    Science.gov (United States)

    Loferski, J. J.

    1976-01-01

    Tandem photovoltaic cells, as proposed by Jackson (1955) to increase the efficiency of solar energy conversion, involve the construction of a system of stacked p/n homojunction photovoltaic cells composed of different semiconductors. It had been pointed out by critics, however, that the total power which could be extracted from the cells in the stack placed side by side was substantially greater than the power obtained from the stacked cells. A reexamination of the tandem cell concept in view of the development of the past few years is conducted. It is concluded that the use of tandem cell systems in flat plate collectors, as originally envisioned by Jackson, may yet become feasible as a result of the development of economically acceptable solar cells for large scale terrestrial power generation.

  18. Solar Cell Panel and the Method for Manufacturing the Same

    Science.gov (United States)

    Richards, Benjamin C. (Inventor); Sarver, Charles F. (Inventor); Naidenkova, Maria (Inventor)

    2016-01-01

    According to an aspect of an embodiment of the present disclosure, there is provided a solar cell panel and a method for manufacturing the same. The solar cell panel comprises: a solar cell for generating electric power from sunlight; a coverglass for covering the solar cell; transparent shims, which are disposed between the solar cell and the coverglass at the points where the distance between the solar cell and the coverglass needs to be controlled, and form a space between the solar cell and the coverglass; and adhesive layer, which fills the space between the solar cell and the coverglass and has the thickness the same as that of the transparent shims.

  19. Industrial n-type solar cells with >20% cell efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Romijn, I.G.; Anker, J.; Burgers, A.R.; Gutjahr, A.; Koppes, M.; Kossen, E.J.; Lamers, M.W.P.E.; Heurtault, Benoit; Saynova-Oosterling, D.S.; Tool, C.J.J. [ECN Solar Energy, Petten (Netherlands)

    2013-03-15

    To realize high efficiencies at low costs, ECN has developed the n-Pasha solar cell concept. The n-Pasha cell concept is a bifacial solar cell concept on n-Cz base material, with which average efficiencies of above 20% have been demonstrated. In this paper recent developments at ECN to improve the cost of ownership (lower Euro/Wp) of the n-Pasha cell concept are discussed. Two main drivers for the manufacturing costs of n-type solar cells are addressed: the n-type Cz silicon material and the silver consumption. We show that a large resistivity range between 2 and 8 cm can be tolerated for high cell efficiency, and that the costs due to the silver metallization can be significantly reduced while increasing the solar cell efficiency. Combining the improved efficiency and cost reduction makes the n-Pasha cell concept a very cost effective solution to manufacture high efficient solar cells and modules.

  20. Recent Advances in Organic Solar Cells

    Directory of Open Access Journals (Sweden)

    Thomas Kietzke

    2007-01-01

    Full Text Available Solar cells based on organic semiconductors have attracted much attention. The thickness of the active layer of organic solar cells is typically only 100 nm thin, which is about 1000 times thinner than for crystalline silicon solar cells and still 10 times thinner than for current inorganic thin film cells. The low material consumption per area and the easy processing of organic semiconductors offer a huge potential for low cost large area solar cells. However, to compete with inorganic solar cells the efficiency of organic solar cells has to be improved by a factor of 2-3. Several organic semiconducting materials have been investigated so far, but the optimum material still has to be designed. Similar as for organic light emitting devices (OLED small molecules are competing with polymers to become the material of choice. After a general introduction into the device structures and operational principles of organic solar cells the three different basic types (all polymer based, all small molecules based and small molecules mixed with polymers are described in detail in this review. For each kind the current state of research is described and the best of class reported efficiencies are listed.

  1. Semiconductor quantum dot-sensitized solar cells.

    Science.gov (United States)

    Tian, Jianjun; Cao, Guozhong

    2013-10-31

    Semiconductor quantum dots (QDs) have been drawing great attention recently as a material for solar energy conversion due to their versatile optical and electrical properties. The QD-sensitized solar cell (QDSC) is one of the burgeoning semiconductor QD solar cells that shows promising developments for the next generation of solar cells. This article focuses on recent developments in QDSCs, including 1) the effect of quantum confinement on QDSCs, 2) the multiple exciton generation (MEG) of QDs, 3) fabrication methods of QDs, and 4) nanocrystalline photoelectrodes for solar cells. We also make suggestions for future research on QDSCs. Although the efficiency of QDSCs is still low, we think there will be major breakthroughs in developing QDSCs in the future.

  2. Development and Prospect of Nanoarchitectured Solar Cells

    OpenAIRE

    Zhang, Bo; Xie, Wenxu; Xiang, Yong

    2015-01-01

    This paper gives an overview of the development and prospect of nanotechnologies utilized in the solar cell applications. Even though it is not clearly pointed out, nanostructures indeed have been used in the fabrication of conventional solar cells for a long time. However, in those circumstances, only very limited benefits of nanostructures have been used to improve cell performance. During the last decade, the development of the photovoltaic device theory and nanofabrication technology enab...

  3. NREL Scientists Report First Solar Cell Producing More Electrons In

    Science.gov (United States)

    measured in operating quantum dot solar cells at low light intensity; these cells showed significant power Photocurrent Than Solar Photons Entering Cell | News | NREL NREL Scientists Report First Solar Cell Producing More Electrons In Photocurrent Than Solar Photons Entering Cell News Release: NREL

  4. Assessment of market possibilities for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Djukanovic, S. [Advanced School of Business Novi Sad (Czechoslovakia)

    2004-07-01

    Global heating increases profitability of solar energy application in the Balkans. The most important market segments for wider solar cells utilization in Yugoslavia (Serbia and Montenegro) are solar pumps for irrigation in agriculture, traffic lights, lighting of weekend houses, air-conditioning, telecommunications, electric vehicles, solar hydro-electric power plants, sports centers and schools and orthodox monasteries. In addition to these applications of solar modules of relatively high capacity, a wide scope of applications of mini solar modules in consumer goods is given serious consideration (flashlights, bicycle lights, fan caps, beach hats, solar parasols, toys for children, solar watches, minicomputers, walkmans and alike). In this paper is projected gradually increase of solar cells applications in Yugoslavia, from 772 kW in 2006., to 3,901 kW installed photovoltaic power in 2010. year. The largest parts of this projected 3.9 MW in 2010., ought to be solar pumps (498 kW), telecommunications (470 kW) and traffic lights (468 kW). (orig.)

  5. Scaling Up ITO-free solar cells

    DEFF Research Database (Denmark)

    Galagan, Yulia; Coenen, Erica W. C.; Zimmermann, Birger

    2014-01-01

    Indium-tin-oxide-free (ITO-free) polymer solar cells with composite electrodes containing current-collecting grids and a semitransparent poly(3,4-ethylenedioxythiophene):polystyrenesulfonate) (PEDOT:PSS) conductor are demonstrated. The up-scaling of the length of the solar cell from 1 to 6 cm...... resistances. The performance of ITO-free organic solar cells with different dimensions and different electrode resistances are evaluated for different light intensities. The current generation and electric potential distribution are found to not be uniformly distributed in large-area devices at simulated 1...

  6. Cheap electricity with autonomous solar cell systems

    International Nuclear Information System (INIS)

    Ouwens, C.D.

    1993-01-01

    A comparison has been made between the costs of an autonomous solar cell system and a centralized electricity supply system. In both cases investment costs are the main issue. It is shown that for households in densely populated sunny areas, the use of autonomous solar cell systems is - even with today's market prices - only as expensive or even cheaper than a grid connection, as long as efficient electric appliances are used. The modular nature of solar cell systems makes it possible to start with any number of appliances, depending on the amount of money available to be spent. (author)

  7. Silicon nanowire-based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Stelzner, Th; Pietsch, M; Andrae, G; Falk, F; Ose, E; Christiansen, S [Institute of Photonic Technology, Albert-Einstein-Strasse 9, D-07745 Jena (Germany)], E-mail: thomas.stelzner@ipht-jena.de

    2008-07-23

    The fabrication of silicon nanowire-based solar cells on silicon wafers and on multicrystalline silicon thin films on glass is described. The nanowires show a strong broadband optical absorption, which makes them an interesting candidate to serve as an absorber in solar cells. The operation of a solar cell is demonstrated with n-doped nanowires grown on a p-doped silicon wafer. From a partially illuminated area of 0.6 cm{sup 2} open-circuit voltages in the range of 230-280 mV and a short-circuit current density of 2 mA cm{sup -2} were obtained.

  8. Silicon nanowire-based solar cells

    International Nuclear Information System (INIS)

    Stelzner, Th; Pietsch, M; Andrae, G; Falk, F; Ose, E; Christiansen, S

    2008-01-01

    The fabrication of silicon nanowire-based solar cells on silicon wafers and on multicrystalline silicon thin films on glass is described. The nanowires show a strong broadband optical absorption, which makes them an interesting candidate to serve as an absorber in solar cells. The operation of a solar cell is demonstrated with n-doped nanowires grown on a p-doped silicon wafer. From a partially illuminated area of 0.6 cm 2 open-circuit voltages in the range of 230-280 mV and a short-circuit current density of 2 mA cm -2 were obtained

  9. Coupling of Luminescent Solar Concentrators to Plasmonic Solar Cells

    Science.gov (United States)

    Wang, Shu-Yi

    To make inexpensive solar cells is a continuous goal for solar photovoltaic (PV) energy industry. Thin film solar cells of various materials have been developed and continue to emerge in order to replace bulk silicon solar cells. A thin film solar cell not only uses less material but also requires a less expensive refinery process. In addition, other advantages coming along with small thickness are higher open circuit voltage and higher conversion efficiency. However, thin film solar cells, especially those made of silicon, have significant optical losses. In order to address this problem, this thesis investigates the spectral coupling of thin films PV to luminescent solar concentrators (LSC). LSC are passive devices, consisting of plastic sheets embedded with fluorescent dyes which absorb part of the incoming radiation spectrum and emit at specific wavelength. The emitted light is concentrated by total internal reflection to the edge of the sheet, where the PVs are placed. Since the light emitted from the LSC edge is usually in a narrow spectral range, it is possible to employ diverse strategies to enhance PV absorption at the peak of the emission wavelength. Employing plasmonic nanostructures has been shown to enhance absorption of thin films via forward scattering, diffraction and localized surface plasmon. These two strategies are theoretically investigated here for improving the absorption and elevating the output power of a thin film solar cell. First, the idea of spectral coupling of luminescent solar concentrators to plasmonic solar cells is introduced to assess its potential for increasing the power output. This study is carried out employing P3HT/PC60BM organic solar cells and LSC with Lumogen Red dyes. A simplified spectral coupling analysis is employed to predict the power density, considering the output spectrum of the LSC equivalent to the emission spectrum of the dye and neglecting any angular dependence. Plasmonic tuning is conducted to enhance

  10. Development and Prospect of Nanoarchitectured Solar Cells

    Directory of Open Access Journals (Sweden)

    Bo Zhang

    2015-01-01

    Full Text Available This paper gives an overview of the development and prospect of nanotechnologies utilized in the solar cell applications. Even though it is not clearly pointed out, nanostructures indeed have been used in the fabrication of conventional solar cells for a long time. However, in those circumstances, only very limited benefits of nanostructures have been used to improve cell performance. During the last decade, the development of the photovoltaic device theory and nanofabrication technology enables studies of more complex nanostructured solar cells with higher conversion efficiency and lower production cost. The fundamental principles and important features of these advanced solar cell designs are systematically reviewed and summarized in this paper, with a focus on the function and role of nanostructures and the key factors affecting device performance. Among various nanostructures, special attention is given to those relying on quantum effect.

  11. Recent Advances in Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Umer Mehmood

    2014-01-01

    Full Text Available Solar energy is an abundant and accessible source of renewable energy available on earth, and many types of photovoltaic (PV devices like organic, inorganic, and hybrid cells have been developed to harness the energy. PV cells directly convert solar radiation into electricity without affecting the environment. Although silicon based solar cells (inorganic cells are widely used because of their high efficiency, they are rigid and manufacturing costs are high. Researchers have focused on organic solar cells to overcome these disadvantages. DSSCs comprise a sensitized semiconductor (photoelectrode and a catalytic electrode (counter electrode with an electrolyte sandwiched between them and their efficiency depends on many factors. The maximum electrical conversion efficiency of DSSCs attained so far is 11.1%, which is still low for commercial applications. This review examines the working principle, factors affecting the efficiency, and key challenges facing DSSCs.

  12. Aqueous-Processed Inorganic Thin-Film Solar Cells Based on CdSe(x)Te(1-x) Nanocrystals: The Impact of Composition on Photovoltaic Performance.

    Science.gov (United States)

    Zeng, Qingsen; Chen, Zhaolai; Zhao, Yue; Du, Xiaohang; Liu, Fangyuan; Jin, Gan; Dong, Fengxia; Zhang, Hao; Yang, Bai

    2015-10-21

    Aqueous processed nanocrystal (NC) solar cells are attractive due to their environmental friendliness and cost effectiveness. Controlling the bandgap of absorbing layers is critical for achieving high efficiency for single and multijunction solar cells. Herein, we tune the bandgap of CdTe through the incorporation of Se via aqueous process. The photovoltaic performance of aqueous CdSexTe1-x NCs is systematically investigated, and the impacts of charge generation, transport, and injection on device performance for different compositions are deeply discussed. We discover that the performance degrades with the increasing Se content from CdTe to CdSe. This is mainly ascribed to the lower conduction band (CB) of CdSexTe1-x with higher Se content, which reduces the driving force for electron injection into TiO2. Finally, the performance is improved by mixing CdSexTe1-x NCs with conjugated polymer poly(p-phenylenevinylene) (PPV), and power conversion efficiency (PCE) of 3.35% is achieved based on ternary NCs. This work may provide some information to further optimize the aqueous-processed NC and hybrid solar cells.

  13. An effective medium model versus a network model for nano-structured solar cells

    International Nuclear Information System (INIS)

    Minnaert, B.; Grasso, C.; Burgelman, M.

    2006-01-01

    In this paper, two methods are compared to model the I-V curves of nano-structured solar cells. These cells consist of an interpenetrating network of an n-type transparent semiconductor oxide (e.g. TiO 2 ) and a p-type semiconductor absorber (e.g. CdTe, CuInS 2 ), deposited on TCO covered glass. The methods are also applicable when a dye and an electrolyte replace the p-semiconductor, and even to organic bulk heterojunction cells. A network model (NM) with resistors and diodes has been published by us before. Another method which has been proposed in the literature is an effective medium model (EMM). In this model, the whole p-n nano-structure is represented by one single effective semiconductor layer, which then is fed into a standard solar cell device simulator, e.g. SCAPS. In this work, it is shown that the NM and the EMM can describe the same physical structure, when they are set up properly. As an illustration, some problems are described both by EMM and NM, and the results are compared. The EMM in this work confirms the results obtained earlier with a simplified NM (constant R n , R p ): when illuminating the n-side, the structure is tolerant to R n but not to R p ; the interpenetrating geometry is disadvantageous for V oc . (authors)

  14. Indium oxide/n-silicon heterojunction solar cells

    Science.gov (United States)

    Feng, Tom; Ghosh, Amal K.

    1982-12-28

    A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

  15. PbSe Nanocrystal Excitonic Solar Cells

    KAUST Repository

    Choi, Joshua J.; Lim, Yee-Fun; Santiago-Berrios, Mitk’ El B.; Oh, Matthew; Hyun, Byung-Ryool; Sun, Liangfeng; Bartnik, Adam C.; Goedhart, Augusta; Malliaras, George G.; Abruña, Héctor D.; Wise, Frank W.; Hanrath, Tobias

    2009-01-01

    that Is distinct from previously reported Schottky devices and consistent with signatures of excitonic solar cells. Remarkably, despite the limitation of planar junction structure, and without film thickness optimization, the best performing device shows a 1-sun

  16. Black Silicon Solar Cells with Black Ribbons

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io

    2016-01-01

    We present the combination of mask-less reactive ion etch (RIE) texturing and blackened interconnecting ribbons as a method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon made by mask-less reactive ion etching has total, average...... in the range 15.7-16.3%. The KOH-textured reference cell had an efficiency of 17.9%. The combination of black Si and black interconnecting ribbons may result in aesthetic, all-black panels based on conventional, front-contacted silicon solar cells....... reflectance below 0.5% across a 156x156 mm2 silicon (Si) wafer. Black interconnecting ribbons were realized by oxidizing copper resulting in reflectance below 3% in the visible wavelength range. Screen-printed Si solar cells were realized on 156x156 mm2 black Si substrates with resulting efficiencies...

  17. Diketopyrrolopyrrole polymers for organic solar cells

    NARCIS (Netherlands)

    Li, Wei Wei; Hendriks, K.H.; Wienk, M.M.; Janssen, R.A.J.

    2016-01-01

    Conspectus Conjugated polymers have been extensively studied for application in organic solar cells. In designing new polymers, particular attention has been given to tuning the absorption spectrum, molecular energy levels, crystallinity, and charge carrier mobility to enhance performance. As a

  18. Silicon Germanium Quantum Well Solar Cell

    Data.gov (United States)

    National Aeronautics and Space Administration — A single crystal SiGe has enormous potentials for high performance chips and solar cells. This project seeks to fabricate a rudimentary but 1st cut quantum-well...

  19. A Bicontinuous Double Gyroid Hybrid Solar Cell

    KAUST Repository

    Crossland, Edward J. W.; Kamperman, Marleen; Nedelcu, Mihaela; Ducati, Caterina; Wiesner, Ulrich; Smilgies, Detlef -M.; Toombes, Gilman E. S.; Hillmyer, Marc A.; Ludwigs, Sabine; Steiner, Ullrich; Snaith, Henry J.

    2009-01-01

    We report the first successful application of an ordered bicontinuous gyroid semiconducting network in a hybrid bulk heterojunction solar cell. The freestanding gyroid network is fabricated by electrochemical deposition into the 10 nm wide voided

  20. Effect of solar-terrestrial phenomena on solar cell's efficiency

    International Nuclear Information System (INIS)

    Zahee, K. B.; Ansari, W.A.; Raza, S.M.M.

    2012-01-01

    It is assumed that the solar cell efficiency of PV device is closely related to the solar irradiance, consider the solar parameter Global Solar Irradiance (G) and the meteorological parameters like daily data of Earth Skin Temperature (E), Average Temperature (T), Relative Humidity (H) and Dew Frost Point (D), for the coastal city Karachi and a non-coastal city Jacobabad, K and J is used as a subscripts for parameters of Karachi and Jacobabad respectively. All variables used here are dependent on the location (latitude and longitude) of our stations except G. To employ ARIMA modeling, the first eighteen years data is used for modeling and forecast is done for the last five years data. In most cases results show good correlation among monthly actual and monthly forecasted values of all the predictors. Next, multiple linear regression is employed to the data obtained by ARIMA modeling and models for mean monthly observed G values are constructed. For each station, two equations are constructed, the R values are above 93% for each model, showing adequacy of the fit. Our computations show that solar cell efficiency can be increased if better modeling for meteorological predictors governs the process. (author)

  1. Perovskite Solar Cells: Progress and Advancements

    Directory of Open Access Journals (Sweden)

    Naveen Kumar Elumalai

    2016-10-01

    Full Text Available Organic–inorganic hybrid perovskite solar cells (PSCs have emerged as a new class of optoelectronic semiconductors that revolutionized the photovoltaic research in the recent years. The perovskite solar cells present numerous advantages include unique electronic structure, bandgap tunability, superior charge transport properties, facile processing, and low cost. Perovskite solar cells have demonstrated unprecedented progress in efficiency and its architecture evolved over the period of the last 5–6 years, achieving a high power conversion efficiency of about 22% in 2016, serving as a promising candidate with the potential to replace the existing commercial PV technologies. This review discusses the progress of perovskite solar cells focusing on aspects such as superior electronic properties and unique features of halide perovskite materials compared to that of conventional light absorbing semiconductors. The review also presents a brief overview of device architectures, fabrication methods, and interface engineering of perovskite solar cells. The last part of the review elaborates on the major challenges such as hysteresis and stability issues in perovskite solar cells that serve as a bottleneck for successful commercialization of this promising PV technology.

  2. Concentrated sunlight for organic solar cells

    DEFF Research Database (Denmark)

    Tromholt, Thomas

    2010-01-01

    . A high solar intensity study of inverted P3HT:PCBM solar cells is presented. Performance peak positions were found to be in the range of 1-5 suns, with smaller cells peaking at higher solar concentrations. Additionally, concentrated sunlight is demonstrated as a practical tool for accelerated stability...... were degraded resulting in acceleration factors in the range of 19-55. This shows that concentrated sunlight can be used as qualitatively to determine the lifetime of polymers under highly accelerated conditions....

  3. Application of photoluminescence imaging and laser-beam-induced-current mapping in thin film solar cell characterization

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Geyuan [Iowa State Univ., Ames, IA (United States)

    2017-05-06

    My research projects are focused on application of photonics, optics and micro- fabrication technology in energy related fields. Photonic crystal fabrication research has the potential to help us generate and use light more efficiently. In order to fabricate active 3D woodpile photonic structure devices, a woodpile template is needed to enable the crystal growth process. We developed a silica woodpile template fabrication process based on two polymer transfer molding technique. A silica woodpile template is demonstrated to work with temperature up to 900 C. It provides a more economical way to explore making better 3D active woodpile photonic devices like 3D photonic light emitting diodes (LED). Optical research on solar cell testing has the potential to make our energy generation more e cient and greener. PL imaging and LBIC mapping are used to measure CdTe solar cells with different back contacts. A strong correlation between PL image defects and LBIC map defects is observed. This opens up potential application for PL imaging in fast solar cell inspection. 2D laser IV scan shows its usage in 2D parameter mapping. We show its ability to generate important information about solar cell performance locally around PL image defects.

  4. CdTe and related compounds: physics, defects, hetero- and nano-structures, crystal growth, surfaces and applications

    CERN Document Server

    Triboulet, Robert

    Almost thirty years after the remarkable monograph of K. Zanio and the numerous conferences and articles dedicated since that time to CdTe and CdZnTe, after all the significant progresses in that field and the increasing interest in these materials for several extremely attractive industrial applications, such as nuclear detectors and solar cells, the edition of a new enriched and updated monograph dedicated to these two very topical II-VI semiconductor compounds, covering all their most prominent, modern and fundamental aspects, seemed very relevant and useful.

  5. High p-type doping, mobility, and photocarrier lifetime in arsenic-doped CdTe single crystals

    Science.gov (United States)

    Nagaoka, Akira; Kuciauskas, Darius; McCoy, Jedidiah; Scarpulla, Michael A.

    2018-05-01

    Group-V element doping is promising for simultaneously maximizing the hole concentration and minority carrier lifetime in CdTe for thin film solar cells, but there are roadblocks concerning point defects including the possibility of self-compensation by AX metastability. Herein, we report on doping, lifetime, and mobility of CdTe single crystals doped with As between 1016 and 1020 cm-3 grown from the Cd solvent by the travelling heater method. Evidence consistent with AX instability as a major contributor to compensation in samples doped below 1017 cm-3 is presented, while for higher-doped samples, precipitation of a second phase on planar structural defects is also observed and may explain spatial variation in properties such as lifetime. Rapid cooling after crystal growth increases doping efficiency and mobility for times up to 20-30 days at room temperature with the highest efficiencies observed close to 45% and a hole mobility of 70 cm2/Vs at room temperature. A doping limit in the low 1017/cm3 range is observed for samples quenched at 200-300 °C/h. Bulk minority carrier lifetimes exceeding 20 ns are observed for samples doped near 1016 cm-3 relaxed in the dark and for unintentionally doped samples, while a lifetime of nearly 5 ns is observed for 1018 cm-3 As doping. These results help us to establish limits on properties expected for group-V doped CdTe polycrystalline thin films for use in photovoltaics.

  6. Doping properties of cadmium-rich arsenic-doped CdTe single crystals: Evidence of metastable AX behavior

    Science.gov (United States)

    Nagaoka, Akira; Kuciauskas, Darius; Scarpulla, Michael A.

    2017-12-01

    Cd-rich composition and group-V element doping are of interest for simultaneously maximizing the hole concentration and minority carrier lifetime in CdTe, but the critical details concerning point defects are not yet fully established. Herein, we report on the properties of arsenic doped CdTe single crystals grown from Cd solvent by the travelling heater method. The photoluminescence spectra and activation energy of 74 ± 2 meV derived from the temperature-dependent Hall effect are consistent with AsTe as the dominant acceptor. Doping in the 1016 to 1017/cm3 range is achieved for measured As concentrations between 1016 and 1020/cm3 with the highest doping efficiency of 40% occurring near 1017 As/cm3. We observe persistent photoconductivity, a hallmark of light-induced metastable configuration changes consistent with AX behavior. Additionally, quenching experiments reveal at least two mechanisms of increased p-type doping in the dark, one decaying over 2-3 weeks and the other persisting for at least 2 months. These results provide essential insights for the application of As-doped CdTe in thin film solar cells.

  7. Method to manufacture solar cells

    International Nuclear Information System (INIS)

    Hanschmann, H.

    1978-01-01

    An attempt has been made to outwit physics and to improve the solar energy utilization in households and space ships by means of power storers, gravitational drive and other futuristic means. (DG) [de

  8. Nanoparticle Solar Cell Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Breeze, Alison, J; Sahoo, Yudhisthira; Reddy, Damoder; Sholin, Veronica; Carter, Sue

    2008-06-17

    The purpose of this work was to demonstrate all-inorganic nanoparticle-based solar cells with photovoltaic performance extending into the near-IR region of the solar spectrum as a pathway towards improving power conversion efficiencies. The field of all-inorganic nanoparticle-based solar cells is very new, with only one literature publication in the prior to our project. Very little is understood regarding how these devices function. Inorganic solar cells with IR performance have previously been fabricated using traditional methods such as physical vapor deposition and sputtering, and solution-processed devices utilizing IR-absorbing organic polymers have been investigated. The solution-based deposition of nanoparticles offers the potential of a low-cost manufacturing process combined with the ability to tune the chemical synthesis and material properties to control the device properties. This work, in collaboration with the Sue Carter research group at the University of California, Santa Cruz, has greatly expanded the knowledge base in this field, exploring multiple material systems and several key areas of device physics including temperature, bandgap and electrode device behavior dependence, material morphological behavior, and the role of buffer layers. One publication has been accepted to Solar Energy Materials and Solar Cells pending minor revision and another two papers are being written now. While device performance in the near-IR did not reach the level anticipated at the beginning of this grant, we did observe one of the highest near-IR efficiencies for a nanoparticle-based solar cell device to date. We also identified several key parameters of importance for improving both near-IR performance and nanoparticle solar cells in general, and demonstrated multiple pathways which showed promise for future commercialization with further research.

  9. Advanced Solar Cells for Satellite Power Systems

    Science.gov (United States)

    Flood, Dennis J.; Weinberg, Irving

    1994-01-01

    The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

  10. 24% efficient PERL structure silicon solar cells

    International Nuclear Information System (INIS)

    Zhao, J.; Wang, A.; Green, M.A.

    1990-01-01

    This paper reports that the performance of silicon solar cells have been significantly improved using an improved PERL (passivated emitter, rear locally-diffused) cell structure. This structure overcomes deficiencies in an earlier PERC (passivated emitter and rear cell) cell structure by locally diffusing boron into contact areas at the rear of the cells. Terrestrial energy conversion efficiencies up to 24% are reported for silicon cells for the first time. Air Mass O efficiencies approach 21%. The first batches of concentrator cells using the new structure have demonstrated significant improvement with 29% efficient concentrator silicon cells expected in the near future

  11. Morphology control and device optimization for efficient organic solar cells

    NARCIS (Netherlands)

    Gevaerts, Veronique

    2013-01-01

    Renewable energy is paramount for a sustainable global future. Solar cells convert solar light directly into electricity and are therefore of great interest in meeting the world’s energy demand. Currently crystalline silicon solar cells dominate the market. Solution processed organic solar cells can

  12. Investigation of solar cell radiation damage

    International Nuclear Information System (INIS)

    Bernard, J.; Reulet, R.; Arndt, R.A.

    1974-01-01

    Development of communications satellites has led to the requirement for a greater and longer lived solar cell power source. Accordingly, studies have been undertaken with the aim of determining which solar cell array provides the greatest power at end of life and the amount of degradation. Investigation of the damage done to thin silicon and thin film CdS solar cells is being carried out in two steps. First, irradiations were performed singly with 0.15, 1.0 and 2.0MeV electrons and 0.7, 2.5 and 22MeV proton. Solar cells and their cover materials were irradiated separately in order to locate the sites of the damage. Diffusion length and I.V. characteristics of the cells and transmission properties of the cover materials were measured. All neasurements were made in vacuum immediately after irradiation. In the second part it is intended to study the effect of various combinations of proton, electron and photon irradiation both with and without an electrical load. The results of this part show whether synergism is involved in solar cell damage and the relative importance of each of three radiation sources if synergism is found [fr

  13. Progress in Thin Film Solar Cells Based on Cu2ZnSnS4

    Directory of Open Access Journals (Sweden)

    Hongxia Wang

    2011-01-01

    Full Text Available The research in thin film solar cells has been dominated by light absorber materials based on CdTe and Cu(In,GaSe2 (CIGS in the last several decades. The concerns of environment impact of cadmium and the limited availability of indium in those materials have driven the research towards developing new substitute light absorbers made from earth abundant, environment benign materials. Cu2ZnSnS4 (CZTS semiconductor material has emerged as one of the most promising candidates for this aim and has attracted considerable interest recently. Significant progress in this relatively new research area has been achieved in the last three years. Over 130 papers on CZTS have been published since 2007, and the majority of them are on the preparation of CZTS thin films by different methods. This paper, will review the wide range of techniques that have been used to deposit CZTS semiconductor thin films. The performance of the thin film solar cells using the CZTS material will also be discussed.

  14. C-V Calculations in CdS/CdTe Thin Films Solar Cells with a CdSxTe1-x Interlayer

    Directory of Open Access Journals (Sweden)

    A. Gonzalez-Cisneros

    2013-01-01

    Full Text Available In CdS/CdTe solar cells, chemical interdiffusion at the interface gives rise to the formation of an interlayer of the ternary compound CdSxCdTe1-x. In this work, we evaluate the effects of this interlayer in CdS/CdTe photovoltaic cells in order to improve theoretical results describing experimental C-V (capacitance versus voltage characteristics. We extended our previous theoretical methodology developed on the basis of three cardinal equations (Castillo-Alvarado et al., 2010. The present results provide a better fit to experimental data obtained from CdS/CdTe solar cells grown in our laboratory by the chemical bath deposition (for CdS film and the close-spaced vapor transport (for CdTe film techniques.

  15. Microscopic optoelectronic defectoscopy of solar cells

    Directory of Open Access Journals (Sweden)

    Dallaeva D.

    2013-05-01

    Full Text Available Scanning probe microscopes are powerful tool for micro- or nanoscale diagnostics of defects in crystalline silicon solar cells. Solar cell is a large p-n junction semiconductor device. Its quality is strongly damaged by the presence of defects. If the cell works under low reverse-biased voltage, defects emit a light in visible range. The suggested method combines three different measurements: electric noise measurement, local topography and near-field optical beam induced current and thus provides more complex information. To prove its feasibility, we have selected one defect (truncated pyramid in the sample, which emitted light under low reverse-biased voltage.

  16. Organic solar cells fundamentals, devices, and upscaling

    CERN Document Server

    Rand, Barry P

    2014-01-01

    Solution-Processed DonorsB. Burkhart, B. C. ThompsonSmall-Molecule and Vapor-Deposited Organic Photovoltaics R. R. Lunt, R. J. HolmesAcceptor Materials for Solution-Processed Solar Cells Y. HeInterfacial Layers R. Po, C. Carbonera, A. BernardiElectrodes in Organic Photovoltaic Cells S. Yoo, J.-Y. Lee, H. Kim, J. LeeTandem and Multi-Junction Organic Solar Cells J. Gilot, R. A. J. JanssenBulk Heterojunction Morphology Control and Characterization T. Wang, D. G. LidzeyOptical Modeling and Light Management

  17. Amorphous silicon crystalline silicon heterojunction solar cells

    CERN Document Server

    Fahrner, Wolfgang Rainer

    2013-01-01

    Amorphous Silicon/Crystalline Silicon Solar Cells deals with some typical properties of heterojunction solar cells, such as their history, the properties and the challenges of the cells, some important measurement tools, some simulation programs and a brief survey of the state of the art, aiming to provide an initial framework in this field and serve as a ready reference for all those interested in the subject. This book helps to "fill in the blanks" on heterojunction solar cells. Readers will receive a comprehensive overview of the principles, structures, processing techniques and the current developmental states of the devices. Prof. Dr. Wolfgang R. Fahrner is a professor at the University of Hagen, Germany and Nanchang University, China.

  18. Solar Cell Calibration and Measurement Techniques

    Science.gov (United States)

    Bailey, Sheila; Brinker, Dave; Curtis, Henry; Jenkins, Phillip; Scheiman, Dave

    2004-01-01

    The increasing complexity of space solar cells and the increasing international markets for both cells and arrays has resulted in workshops jointly sponsored by NASDA, ESA and NASA. These workshops are designed to obtain international agreement on standardized values for the AMO spectrum and constant, recommend laboratory measurement practices and establish a set of protocols for international comparison of laboratory measurements. A working draft of an ISO standard, WD15387, "Requirements for Measurement and Calibration Procedures for Space Solar Cells" was discussed with a focus on the scope of the document, a definition of primary standard cell, and required error analysis for all measurement techniques. Working groups addressed the issues of Air Mass Zero (AMO) solar constant and spectrum, laboratory measurement techniques, and te international round robin methodology. A summary is presented of the current state of each area and the formulation of the ISO document.

  19. Dye-sensitised solar cell (artificial photosynthesis)

    CSIR Research Space (South Africa)

    Le Roux, Lukas J

    2006-02-01

    Full Text Available is the nano- crystalline TiO2dye- sensitised solar cell (DSC), in conjunction with several new concepts, such as nanotechnology and molecular devices. An efficient and low-cost cell can be produced by using simple materials. The production process generates...

  20. Walking-Beam Solar-Cell Conveyor

    Science.gov (United States)

    Feder, H.; Frasch, W.

    1982-01-01

    Microprocessor-controlled walking-beam conveyor moves cells between work stations in automated assembly line. Conveyor has arm at each work station. In unison arms pick up all solar cells and advance them one station; then beam retracks to be in position for next step. Microprocessor sets beam stroke, speed, and position.

  1. Polymer-fullerene bulk heterojunction solar cells

    NARCIS (Netherlands)

    Janssen, RAJ; Hummelen, JC; Saricifti, NS

    Nanostructured phase-separated blends, or bulk heterojunctions, of conjugated Polymers and fullerene derivatives form a very attractive approach to large-area, solid-state organic solar cells.The key feature of these cells is that they combine easy, processing from solution on a variety of

  2. High-efficiency concentrator silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Sinton, R.A.; Cuevas, A.; King, R.R.; Swanson, R.M. (Stanford Univ., CA (USA). Solid-State Electronics Lab.)

    1990-11-01

    This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm{sup 2} cell with front grids achieved 26% efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21--22% for one-sun cells in sizes up to 37.5 cm{sup 2}. An efficiency of 26% was achieved for similar 0.64-cm{sup 2} concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling. 68 refs., 50 figs.

  3. Radiation resistant passivation of silicon solar cells

    International Nuclear Information System (INIS)

    Swanson, R.M.; Gan, J.Y.; Gruenbaum, P.E.

    1991-01-01

    This patent describes a silicon solar cell having improved stability when exposed to concentrated solar radiation. It comprises a body of silicon material having a major surface for receiving radiation, a plurality of p and n conductivity regions in the body for collecting electrons and holes created by impinging radiation, and a passivation layer on the major surface including a first layer of silicon oxide in contact with the body and a polycrystalline silicon layer on the first layer of silicon oxide

  4. Cytotoxicity assessment of functionalized CdSe, CdTe and InP quantum dots in two human cancer cell models

    International Nuclear Information System (INIS)

    Liu, Jing; Hu, Rui; Liu, Jianwei; Zhang, Butian; Wang, Yucheng; Liu, Xin; Law, Wing-Cheung; Liu, Liwei; Ye, Ling; Yong, Ken-Tye

    2015-01-01

    protocols are urgently needed to be developed and employed for fully assessing and understanding the origins of the toxicity arising from different QD formulations. - Highlights: • The cytotoxicity of CdSe, CdTe and InP based on four QD formulations were assessed. • Gastric adenocarcinoma and neuroblastoma cells showed different toxicity responses. • Multi-factors including core, coating and cell type contribute to QD cytotoxicity. • The cellular uptake of QDs plays an important role in the toxicity impact of QDs

  5. Cytotoxicity assessment of functionalized CdSe, CdTe and InP quantum dots in two human cancer cell models

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jing [Institute of Gerontology and Geriatrics & Beijing Key Lab of Aging and Geriatrics, Chinese PLA General Hospital, Beijing 100853 (China); Hu, Rui [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Liu, Jianwei [Institute of Gerontology and Geriatrics & Beijing Key Lab of Aging and Geriatrics, Chinese PLA General Hospital, Beijing 100853 (China); Zhang, Butian; Wang, Yucheng [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Liu, Xin [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Law, Wing-Cheung [Department of Industrial and System Engineering, The Hang Kong Polytechnic University, Hung Hom (Hong Kong); Liu, Liwei [School of Science, Changchun University of Science and Technology, Changchun 130022 (China); Ye, Ling, E-mail: lye_301@163.com [Institute of Gerontology and Geriatrics & Beijing Key Lab of Aging and Geriatrics, Chinese PLA General Hospital, Beijing 100853 (China); Yong, Ken-Tye, E-mail: ktyong@ntu.edu.sg [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2015-12-01

    protocols are urgently needed to be developed and employed for fully assessing and understanding the origins of the toxicity arising from different QD formulations. - Highlights: • The cytotoxicity of CdSe, CdTe and InP based on four QD formulations were assessed. • Gastric adenocarcinoma and neuroblastoma cells showed different toxicity responses. • Multi-factors including core, coating and cell type contribute to QD cytotoxicity. • The cellular uptake of QDs plays an important role in the toxicity impact of QDs.

  6. Development of large area, high efficiency amorphous silicon solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, K.S.; Kim, S.; Kim, D.W. [Yu Kong Taedok Institute of Technology (Korea, Republic of)

    1996-02-01

    The objective of the research is to develop the mass-production technologies of high efficiency amorphous silicon solar cells in order to reduce the costs of solar cells and dissemination of solar cells. Amorphous silicon solar cell is the most promising option of thin film solar cells which are relatively easy to reduce the costs. The final goal of the research is to develop amorphous silicon solar cells having the efficiency of 10%, the ratio of light-induced degradation 15% in the area of 1200 cm{sup 2} and test the cells in the form of 2 Kw grid-connected photovoltaic system. (author) 35 refs., 8 tabs., 67 figs.

  7. Influence of the optical window on the performance of TCO/CdS/CdTe solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Gordillo, G [Universidad Nacional de Colombia, Bogota (Colombia). Dept. de Fisica; Grizalez, M [Univ. de la Amazonia, Florencia (Colombia); Moreno, L C [Dept. de Quimica, Univ. Nacional de Colombia, Bogota (Colombia); Landazabal, F [Dept. de Fisica, Univ. de Cundinamarca, Fusagasuga (Colombia)

    2000-07-01

    Thin film solar cells, with structure TCO/CdS/CdTe/Cu, were fabricated using the transparent conducting oxides (TCOs) SnO{sub 2}:F, deposited by spray pyrolysis, and ZnO, deposited by reactive evaporation, as transparent electrodes. The TCO/CdS system with the CdS layer deposited by CBD (chemical bath deposition) method acts in the cell as an optical window and the CdTe deposited by CSS (close space sublimation) method acts as absorber layer, being the unique active layer of the cell. Details of the technological aspects of the solar cells fabrication as well as a discussion to explain the effect of the TCO layer on the solar cell performance will be given. The best results obtained in this work were: open circuit voltage of 0.57 V, short circuit current of 13 mA/cm{sup 2}, fill factor of 0.63 and conversion efficiency of 5.8%. (orig.)

  8. Solar heating of GaAs nanowire solar cells.

    Science.gov (United States)

    Wu, Shao-Hua; Povinelli, Michelle L

    2015-11-30

    We use a coupled thermal-optical approach to model the operating temperature rise in GaAs nanowire solar cells. We find that despite more highly concentrated light absorption and lower thermal conductivity, the overall temperature rise in a nanowire structure is no higher than in a planar structure. Moreover, coating the nanowires with a transparent polymer can increase the radiative cooling power by 2.2 times, lowering the operating temperature by nearly 7 K.

  9. Neutral Color Semitransparent Microstructured Perovskite Solar Cells

    KAUST Repository

    Eperon, Giles E.

    2014-01-28

    Neutral-colored semitransparent solar cells are commercially desired to integrate solar cells into the windows and cladding of buildings and automotive applications. Here, we report the use of morphological control of perovskite thin films to form semitransparent planar heterojunction solar cells with neutral color and comparatively high efficiencies. We take advantage of spontaneous dewetting to create microstructured arrays of perovskite "islands", on a length-scale small enough to appear continuous to the eye yet large enough to enable unattenuated transmission of light between the islands. The islands are thick enough to absorb most visible light, and the combination of completely absorbing and completely transparent regions results in neutral transmission of light. Using these films, we fabricate thin-film solar cells with respectable power conversion efficiencies. Remarkably, we find that such discontinuous films still have good rectification behavior and relatively high open-circuit voltages due to the inherent rectification between the n- and p-type charge collection layers. Furthermore, we demonstrate the ease of "color-tinting" such microstructured perovksite solar cells with no reduction in performance, by incorporation of a dye within the hole transport medium. © 2013 American Chemical Society.

  10. Light-trapping in perovskite solar cells

    Directory of Open Access Journals (Sweden)

    Qing Guo Du

    2016-06-01

    Full Text Available We numerically demonstrate enhanced light harvesting efficiency in both CH3NH3PbI3 and CH(NH22PbI3-based perovskite solar cells using inverted vertical-cone photonic-crystal nanostructures. For CH3NH3PbI3 perovskite solar cells, the maximum achievable photocurrent density (MAPD reaches 25.1 mA/cm2, corresponding to 92% of the total available photocurrent in the absorption range of 300 nm to 800 nm. Our cell shows 6% absorption enhancement compared to the Lambertian limit (23.7 mA/cm2 and has a projected power conversion efficiency of 12.9%. Excellent solar absorption is numerically demonstrated over a broad angular range from 0 to 60 degree for both S- and P- polarizations. For the corresponding CH(NH22PbI3 based perovskite solar cell, with absorption range of 300 nm to 850 nm, we find a MAPD of 29.1 mA/cm2, corresponding to 95.4% of the total available photocurrent. The projected power conversion efficiency of the CH(NH22PbI3 based photonic crystal solar cell is 23.4%, well above the current world record efficiency of 20.1%.

  11. Light-trapping in perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Du, Qing Guo, E-mail: duqi0001@e.ntu.edu.sg [Department of Physics, University of Toronto, 60 ST. George St., Toronto, Ontario, M5S 1A7 (Canada); Institute of High Performance Computing, A* STAR, Singapore, 138632 (Singapore); Shen, Guansheng [Department of Physics, University of Toronto, 60 ST. George St., Toronto, Ontario, M5S 1A7 (Canada); School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876 (China); John, Sajeev [Department of Physics, University of Toronto, 60 ST. George St., Toronto, Ontario, M5S 1A7 (Canada); Department of Physics, Soochow University, Suzhou (China)

    2016-06-15

    We numerically demonstrate enhanced light harvesting efficiency in both CH{sub 3}NH{sub 3}PbI{sub 3} and CH(NH{sub 2}){sub 2}PbI{sub 3}-based perovskite solar cells using inverted vertical-cone photonic-crystal nanostructures. For CH{sub 3}NH{sub 3}PbI{sub 3} perovskite solar cells, the maximum achievable photocurrent density (MAPD) reaches 25.1 mA/cm{sup 2}, corresponding to 92% of the total available photocurrent in the absorption range of 300 nm to 800 nm. Our cell shows 6% absorption enhancement compared to the Lambertian limit (23.7 mA/cm{sup 2}) and has a projected power conversion efficiency of 12.9%. Excellent solar absorption is numerically demonstrated over a broad angular range from 0 to 60 degree for both S- and P- polarizations. For the corresponding CH(NH{sub 2}){sub 2}PbI{sub 3} based perovskite solar cell, with absorption range of 300 nm to 850 nm, we find a MAPD of 29.1 mA/cm{sup 2}, corresponding to 95.4% of the total available photocurrent. The projected power conversion efficiency of the CH(NH{sub 2}){sub 2}PbI{sub 3} based photonic crystal solar cell is 23.4%, well above the current world record efficiency of 20.1%.

  12. Investigation of Processing, Microstructures and Efficiencies of Polycrystalline CdTe Photovoltaic Films and Devices

    Science.gov (United States)

    Munshi, Amit Harenkumar

    CdTe based photovoltaics have been commercialized at multiple GWs/year level. The performance of CdTe thin film photovoltaic devices is sensitive to process conditions. Variations in deposition temperatures as well as other treatment parameters have a significant impact on film microstructure and device performance. In this work, extensive investigations are carried out using advanced microstructural characterization techniques in an attempt to relate microstructural changes due to varying deposition parameters and their effects on device performance for cadmium telluride based photovoltaic cells deposited using close space sublimation (CSS). The goal of this investigation is to apply advanced material characterization techniques to aid process development for higher efficiency CdTe based photovoltaic devices. Several techniques have been used to observe the morphological changes to the microstructure along with materials and crystallographic changes as a function of deposition temperature and treatment times. Traditional device structures as well as advanced structures with electron reflector and films deposited on Mg1-xZnxO instead of conventional CdS window layer are investigated. These techniques include Scanning Electron Microscopy (SEM) with Electron Back Scattered Diffraction (EBSD) and Energy dispersive X-ray spectroscopy (EDS) to study grain structure and High Resolution Transmission Electron Microscopy (TEM) with electron diffraction and EDS. These investigations have provided insights into the mechanisms that lead to change in film structure and device performance with change in deposition conditions. Energy dispersive X-ray spectroscopy (EDS) is used for chemical mapping of the films as well as to understand interlayer material diffusion between subsequent layers. Electrical performance of these devices has been studied using current density vs voltage plots. Devices with efficiency over 18% have been fabricated on low cost commercial glass substrates

  13. Quantum-Tuned Multijunction Solar Cells

    Science.gov (United States)

    Koleilat, Ghada I.

    Multijunction solar cells made from a combination of CQDs of differing sizes and thus bandgaps are a promising means by which to increase the energy harvested from the Sun's broad spectrum. In this dissertation, we first report the systematic engineering of 1.6 eV PbS CQD solar cells, optimal as the front cell responsible for visible wavelength harvesting in tandem photovoltaics. We rationally optimize each of the device's collecting electrodes---the heterointerface with electron accepting TiO2 and the deep-work-function hole-collecting MoO3 for ohmic contact---for maximum efficiency. Room-temperature processing enables flexible substrates, and permits tandem solar cells that integrate a small-bandgap back cell atop a low thermal-budget larger-bandgap front cell. We report an electrode strategy that enables a depleted heterojunction CQD PV device to be fabricated entirely at room temperature. We develop a two-layer donor-supply electrode (DSE) in which a highly doped, shallow work function layer supplies a high density of free electrons to an ultrathin TiO2 layer via charge-transfer doping. Using the DSE we build all-room-temperature-processed small-bandgap (1 eV) colloidal quantum dot solar cells suitable for use as the back junction in tandem solar cells. We further report in this work the first efficient CQD tandem solar cells. We use a graded recombination layer (GRL) to provide a progression of work functions from the hole-accepting electrode in the bottom cell to the electron-accepting electrode in the top cell. The recombination layers must allow the hole current from one cell to recombine, with high efficiency and low voltage loss, with the electron current from the next cell. We conclude our dissertation by presenting the generalized conditions for design of efficient graded recombination layer solar devices. We demonstrate a family of new GRL designs experimentally and highlight the benefits of the progression of dopings and work functions in the

  14. Morphology of polymer solar cells

    DEFF Research Database (Denmark)

    Böttiger, Arvid P.L.

    as a function of polymer, type of ink, annealing etc. Ptychography is a new state of the art X-ray imaging technique based on coherent scattering. Together with Scanning X-ray Transmission Microscopy (STXM) it has been used in this study to inspect the morphology of the active layer taken from working solar...

  15. Achievement report for fiscal 1997. Technological development for practical application of a solar energy power generation system (development of technology to manufacture thin film solar cells (surveys and researches on analyzing practical application )). Volume 1; 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu (jitsuyoka kaiseki ni kansuru chosa kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    It is intended to identify and analyze quickly and accurately the technological trends inside and outside the country on thin film solar cells, to reflect the results effectively on research and development of practical application of the thin film solar cells for power use, and to aid the research on practical application of the technology to manufacture the thin film solar cells. This fiscal year introduced the new project of researching and developing the poly-crystal silicon-based thin film solar cells. Discussions were given on designing the solar cells, including setting of thickness of an active layer required to improve efficiency of the silicon-based thin film solar cells, the light confining technology, and surface passivation. Comparisons and discussions were given on the new amorphous/poly-crystal silicon thin film manufacturing method and the conventional plasma CVD process. A research development program was introduced for a super laboratory to aid establishing the practical application technology for the silicon-based thin film solar cells. Chalcopyrite compounds including CuInSe2, and CdTe have not shown deterioration even in a long-term outdoor exposure test, hence they are noted as materials for high-efficiency solar cells and studied actively. Although still small in area, the net conversion efficiency was found in the order of 17%. Technological development has started to search mass production processes and commercialization possibility in the future. (NEDO)

  16. Stability Issues on Perovskite Solar Cells

    Directory of Open Access Journals (Sweden)

    Xing Zhao

    2015-11-01

    Full Text Available Organo lead halide perovskite materials like methylammonium lead iodide (CH3NH3PbI3 and formamidinium lead iodide (HC(NH22PbI3 show superb opto-electronic properties. Based on these perovskite light absorbers, power conversion efficiencies of the perovskite solar cells employing hole transporting layers have increased from 9.7% to 20.1% within just three years. Thus, it is apparent that perovskite solar cell is a promising next generation photovoltaic technology. However, the unstable nature of perovskite was observed when exposing it to continuous illumination, moisture and high temperature, impeding the commercial development in the long run and thus becoming the main issue that needs to be solved urgently. Here, we discuss the factors affecting instability of perovskite and give some perspectives about further enhancement of stability of perovskite solar cell.

  17. Fabricating solar cells with silicon nanoparticles

    Science.gov (United States)

    Loscutoff, Paul; Molesa, Steve; Kim, Taeseok

    2014-09-02

    A laser contact process is employed to form contact holes to emitters of a solar cell. Doped silicon nanoparticles are formed over a substrate of the solar cell. The surface of individual or clusters of silicon nanoparticles is coated with a nanoparticle passivation film. Contact holes to emitters of the solar cell are formed by impinging a laser beam on the passivated silicon nanoparticles. For example, the laser contact process may be a laser ablation process. In that case, the emitters may be formed by diffusing dopants from the silicon nanoparticles prior to forming the contact holes to the emitters. As another example, the laser contact process may be a laser melting process whereby portions of the silicon nanoparticles are melted to form the emitters and contact holes to the emitters.

  18. A special issue on solar cells

    Institute of Scientific and Technical Information of China (English)

    Yi-Bing CHENG

    2011-01-01

    @@ The increasing demand for renewable energy has made the solar cell technology as one of the most significantresearch and development areas of today.Silicon based solar cells are the dominant photovoltaic products at the present time, but the relatively high costs are barriers for their broad applications.Research has been active worldwide in developing other photovoltaic technologies that use cheap materials and can be easily manufactured.Organic solar cells have attracted a lot of interests recently due to their potential to be low cost photovoltaic technologies.This special issue of the Frontiers of Optoelectronics in China has collected research articles by a number of Chinese and international experts.It is aimed to broaden the readers' view about some of the recent developments and challenges in this important R&D field.Thirteen excellent papers are in this special issue including 4 review articles and 9 research articles.

  19. Doctor Blade-Coated Polymer Solar Cells

    KAUST Repository

    Cho, Nam Chul

    2016-10-25

    In this work, we report polymer solar cells based on blade-coated P3HT:PC71BM and PBDTTT-EFT:PC71BM bulk heterojunction photoactive layers. Enhanced power conversion efficiency of 2.75 (conventional structure) and 3.03% (inverted structure) with improved reproducibility was obtained from blade-coated P3HT:PC71BM solar cells, compared to spin-coated ones. Furthermore, by demonstrating 3.10% efficiency flexible solar cells using blade-coated PBDTTT-EFT:PC71BM films on the plastic substrates, we suggest the potential applicability of blade coating technique to the high throughput roll-to-roll fabrication systems.

  20. Perovskite Solar Cells: Potentials, Challenges, and Opportunities

    Directory of Open Access Journals (Sweden)

    Muhammad Imran Ahmed

    2015-01-01

    Full Text Available Heralded as a major scientific breakthrough of 2013, organic/inorganic lead halide perovskite solar cells have ushered in a new era of renewed efforts at increasing the efficiency and lowering the cost of solar energy. As a potential game changer in the mix of technologies for alternate energy, it has emerged from a modest beginning in 2012 to efficiencies being claimed at 20.1% in a span of just two years. This remarkable progress, encouraging at one end, also points to the possibility that the potential may still be far from being fully realized. With greater insight into the photophysics involved and optimization of materials and methods, this technology stands to match or even exceed the efficiencies for single crystal silicon solar cells. With thin film solution processability, applicability to flexible substrates, and being free of liquid electrolyte, this technology combines the benefits of Dye Sensitized Solar Cells (DSSCs, Organic Photovoltaics (OPVs, and thin film solar cells. In this review we present a brief historic perspective to this development, take a cognizance of the current state of the art, and highlight challenges and the opportunities.

  1. Questionable effects of antireflective coatings on inefficiently cooled solar cells

    DEFF Research Database (Denmark)

    Akhmatov, Vladislav; Galster, Georg; Larsen, Esben

    1998-01-01

    of the output power and efficiency curves throughout the day the coherence between technical parameters of the solar cells and the climate in the operation region is observed and examined. It is shown how the drop in output power around noon can be avoided by fitting technical parameters of the solar cells......A model for temperature effects in p-n junction solar cells is introduced. The temperature of solar cells and the losses in the solar cell junction region caused by elevating temperature are discussed. The model developed is examined for low-cost silicon solar cells. In order to improve the shape...

  2. Application of porous silicon in solar cell

    Science.gov (United States)

    Maniya, Nalin H.; Ashokan, Jibinlal; Srivastava, Divesh N.

    2018-05-01

    Silicon is widely used in solar cell applications with over 95% of all solar cells produced worldwide composed of silicon. Nanostructured thin porous silicon (PSi) layer acting as anti-reflecting coating is used in photovoltaic solar cells due to its advantages including simple and low cost fabrication, highly textured surfaces enabling lowering of reflectance, controllability of thickness and porosity of layer, and high surface area. PSi layers have previously been reported to reduce the reflection of light and replaced the conventional anti-reflective coating layers on solar cells. This can essentially improve the efficiency and decrease the cost of silicon solar cells. Here, we investigate the reflectance of different PSi layers formed by varying current density and etching time. PSi layers were formed by a combination of current density including 60 and 80 mA/cm2 and time for fabrication as 2, 4, 6, and 8 seconds. The fabricated PSi layers were characterized using reflectance spectroscopy and field emission scanning electron microscopy. Thickness and pore size of PSi layer were increased with increase in etching time and current density, respectively. The reflectance of PSi layers was decreased with increase in etching time until 6 seconds and increased again after 6 seconds, which was observed across both the current density. Reduction in reflectance indicates the increase of absorption of light by silicon due to the thin PSi layer. In comparison with the reflectance of silicon wafer, PSi layer fabricated at 80 mA/cm2 for 6 seconds gave the best result with reduction in reflectance up to 57%. Thus, the application of PSi layer as an effective anti-reflecting coating for the fabrication of solar cell has been demonstrated.

  3. High throughput solar cell ablation system

    Science.gov (United States)

    Harley, Gabriel; Pass, Thomas; Cousins, Peter John; Viatella, John

    2012-09-11

    A solar cell is formed using a solar cell ablation system. The ablation system includes a single laser source and several laser scanners. The laser scanners include a master laser scanner, with the rest of the laser scanners being slaved to the master laser scanner. A laser beam from the laser source is split into several laser beams, with the laser beams being scanned onto corresponding wafers using the laser scanners in accordance with one or more patterns. The laser beams may be scanned on the wafers using the same or different power levels of the laser source.

  4. Origami-enabled deformable silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Rui; Huang, Hai; Liang, Hanshuang; Liang, Mengbing [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); Tu, Hongen; Xu, Yong [Electrical and Computer Engineering, Wayne State University, 5050 Anthony Wayne Dr., Detroit, Michigan 48202 (United States); Song, Zeming; Jiang, Hanqing, E-mail: hanqing.jiang@asu.edu [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States); Yu, Hongyu, E-mail: hongyu.yu@asu.edu [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287 (United States)

    2014-02-24

    Deformable electronics have found various applications and elastomeric materials have been widely used to reach flexibility and stretchability. In this Letter, we report an alternative approach to enable deformability through origami. In this approach, the deformability is achieved through folding and unfolding at the creases while the functional devices do not experience strain. We have demonstrated an example of origami-enabled silicon solar cells and showed that this solar cell can reach up to 644% areal compactness while maintaining reasonable good performance upon cyclic folding/unfolding. This approach opens an alternative direction of producing flexible, stretchable, and deformable electronics.

  5. Origami-enabled deformable silicon solar cells

    International Nuclear Information System (INIS)

    Tang, Rui; Huang, Hai; Liang, Hanshuang; Liang, Mengbing; Tu, Hongen; Xu, Yong; Song, Zeming; Jiang, Hanqing; Yu, Hongyu

    2014-01-01

    Deformable electronics have found various applications and elastomeric materials have been widely used to reach flexibility and stretchability. In this Letter, we report an alternative approach to enable deformability through origami. In this approach, the deformability is achieved through folding and unfolding at the creases while the functional devices do not experience strain. We have demonstrated an example of origami-enabled silicon solar cells and showed that this solar cell can reach up to 644% areal compactness while maintaining reasonable good performance upon cyclic folding/unfolding. This approach opens an alternative direction of producing flexible, stretchable, and deformable electronics

  6. Microstructured extremely thin absorber solar cells

    DEFF Research Database (Denmark)

    Biancardo, Matteo; Krebs, Frederik C

    2007-01-01

    In this paper we present the realization of extremely thin absorber (ETA) solar cells employing conductive glass substrates functionalized with TiO2 microstructures produced by embossing. Nanocrystalline or compact TiO2 films on Indium doped tin oxide (ITO) glass substrates were embossed by press......In this paper we present the realization of extremely thin absorber (ETA) solar cells employing conductive glass substrates functionalized with TiO2 microstructures produced by embossing. Nanocrystalline or compact TiO2 films on Indium doped tin oxide (ITO) glass substrates were embossed...

  7. Design issues for optimum solar cell configuration

    Science.gov (United States)

    Kumar, Atul; Thakur, Ajay D.

    2018-05-01

    A computer based simulation of solar cell structure is performed to study the optimization of pn junction configuration for photovoltaic action. The fundamental aspects of photovoltaic action viz, absorption, separation collection, and their dependence on material properties and deatails of device structures is discussed. Using SCAPS 1D we have simulated the ideal pn junction and shown the effect of band offset and carrier densities on solar cell performance. The optimum configuration can be achieved by optimizing transport of carriers in pn junction under effect of field dependent recombination (tunneling) and density dependent recombination (SRH, Auger) mechanisms.

  8. Management of light absorption in extraordinary optical transmission based ultra-thin-film tandem solar cells

    International Nuclear Information System (INIS)

    Mashooq, Kishwar; Talukder, Muhammad Anisuzzaman

    2016-01-01

    polygon, total absorption remains approximately the same. However, the total absorption suffers significantly if the holes are triangle. The transmission spectra of incident light into the bottom subcell, and hence the absorption, change significantly for square and circle holes if the active materials change to cadmium selenide (CdSe) and cadmium telluride (CdTe) in the top and bottom subcells, respectively. Although the intermediate metal layer may induce electron-hole pair recombination due to surface defects, the short-circuit current density of an ultra-thin plasmonic solar cell with an intermediate metal layer with two-dimensional hole array is >9% of that of a structure without the intermediate metal layer.

  9. Management of light absorption in extraordinary optical transmission based ultra-thin-film tandem solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Mashooq, Kishwar; Talukder, Muhammad Anisuzzaman, E-mail: anis@eee.buet.ac.bd [Department of Electrical and Electronic Engineering, Bangladesh University of Engineering and Technology, Dhaka 1205 (Bangladesh)

    2016-05-21

    polygon, total absorption remains approximately the same. However, the total absorption suffers significantly if the holes are triangle. The transmission spectra of incident light into the bottom subcell, and hence the absorption, change significantly for square and circle holes if the active materials change to cadmium selenide (CdSe) and cadmium telluride (CdTe) in the top and bottom subcells, respectively. Although the intermediate metal layer may induce electron-hole pair recombination due to surface defects, the short-circuit current density of an ultra-thin plasmonic solar cell with an intermediate metal layer with two-dimensional hole array is >9% of that of a structure without the intermediate metal layer.

  10. High efficiency double sided solar cells

    International Nuclear Information System (INIS)

    Seddik, M.M.

    1990-06-01

    Silicon technology state of the art for single crystalline was given to be limited to less than 20% efficiency. A proposed new form of photovoltaic solar cell of high current high efficiency with double sided structures has been given. The new forms could be n ++ pn ++ or p ++ np ++ double side junctions. The idea of double sided devices could be understood as two solar cells connected back-to-back in parallel electrical connection, in which the current is doubled if the cell is illuminated from both sides by a V-shaped reflector. The cell is mounted to the reflector such that each face is inclined at an angle of 45 deg. C to each side of the reflector. The advantages of the new structure are: a) High power devices. b) Easy to fabricate. c) The cells are used vertically instead of horizontal use of regular solar cell which require large area to install. This is very important in power stations and especially for satellite installation. If the proposal is made real and proved to be experimentally feasible, it would be a new era for photovoltaic solar cells since the proposal has already been extended to even higher currents. The suggested structures could be stated as: n ++ pn ++ Vp ++ np ++ ;n ++ pn ++ Vn ++ pn ++ ORp ++ np ++ Vp ++ np ++ . These types of structures are formed in wedged shape to employ indirect illumination by either parabolic; conic or V-shaped reflectors. The advantages of these new forms are low cost; high power; less in size and space; self concentrating; ... etc. These proposals if it happens to find their ways to be achieved experimentally, I think they will offer a short path to commercial market and would have an incredible impact on solar cell technology and applications. (author). 12 refs, 5 figs

  11. The Role of Interface States and Series Resistance on the Current Voltage (I-V) Characterises of Au/n-CdTe Solar Cells

    International Nuclear Information System (INIS)

    Fiat, S.

    2008-01-01

    In order to well interpret the experimentally observed nonideal Au/n-CdTe solar cells parameters such as the zero-bias barrier height ( Φ B o), ideality factor (n), interface states (Nss) and series resistance. The energy distribution profile of Nss was obtained from forward bias I-V characteristics by taking in to account the bias dependent of the effective barrier height (Φ e )at room temperature.The values of Rs obtained from Cheung's functions. The higher values of n and Rs were attributed to the existence of a native insulator layer on CdTe surface and to high density of Nss localized at semiconductor/ insulator layer interface. The experimental I-V characteristics confirmed that the the thickness of insulator layer (δ o x) ,magnitude or Rs and Nss and a particular distribution of Nss in the band gap are important parameters that influence the electrical parameters of Au/n-CdTe solar cells

  12. Development of high-performance transparent conducting oxides and their impact on the performance of CdS/CdTe solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Coutts, T.J.; Wu, X.; Sheldon, P.; Rose, D.H. [National Renewable Energy Lab., Golden, CO (United States)

    1998-09-01

    This paper begins with a review of the modeled performance of transparent conducting oxides (TCOs) as a function of their free-carrier concentration, mobility, and film thickness. It is shown that it is vital to make a film with high mobility to minimize the width and height of the free-carrier absorption band, and to optimize the optical properties. The free-carrier concentration must be kept sufficiently small that the absorption band does not extend into that part of the spectrum to which the solar cell responds. Despite this consideration, a high electrical conductivity is essential to minimize series resistance losses. Hence, a high mobility is vital for these materials. The fabrication of thin-films of cadmium stannate is then discussed, and their performance is compared with that of tin oxide, both optically and as these materials influence the performance of CdTe solar cells.

  13. Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

    International Nuclear Information System (INIS)

    Gross, Dieter Konrad Michael

    2013-01-01

    electronic Dexter energy transfer. On the other hand, it may pave the way for imitation of the natural photosynthesis where both energy transfer and charge separation are realized on the nanoscale. The nanocrystals may be used as building blocks to replace the organic molecules of natural processes. The closely packed selfassembly of type II aligned nanocrystals may find application in solid state devices such as extremely thin absorber solar cells with surface enhanced substrates. Also colloidal application for water splitting may be an option, where semiconductor nanocrystals may provide both energy transfer and charge separation. The organic barrier around the particles may help to protect the semiconductor nanocrystals against degradation during photo-catalytic water splitting. Moreover, the semiconductor nanocrystals may be used as a tape rule for sensing the relative energetic alignment to other nanoparticles or molecules. The PL-quenching rate correlates with the offset of the energy levels which can be tuned due to the quantum confinement effect. PL-quenching studies may reveal the relative energetic alignment of other nanoparticles when experimental series of their closely packed hybrid assemblies with different nanocrystal sizes are analyzed.

  14. Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Dieter Konrad Michael

    2013-11-08

    electronic Dexter energy transfer. On the other hand, it may pave the way for imitation of the natural photosynthesis where both energy transfer and charge separation are realized on the nanoscale. The nanocrystals may be used as building blocks to replace the organic molecules of natural processes. The closely packed selfassembly of type II aligned nanocrystals may find application in solid state devices such as extremely thin absorber solar cells with surface enhanced substrates. Also colloidal application for water splitting may be an option, where semiconductor nanocrystals may provide both energy transfer and charge separation. The organic barrier around the particles may help to protect the semiconductor nanocrystals against degradation during photo-catalytic water splitting. Moreover, the semiconductor nanocrystals may be used as a tape rule for sensing the relative energetic alignment to other nanoparticles or molecules. The PL-quenching rate correlates with the offset of the energy levels which can be tuned due to the quantum confinement effect. PL-quenching studies may reveal the relative energetic alignment of other nanoparticles when experimental series of their closely packed hybrid assemblies with different nanocrystal sizes are analyzed.

  15. Advances in solar cell welding technology

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, L.G.; Lott, D.R.

    1982-09-01

    In addition to developing the rigid substrate welded conventional cell panels for an earlier U.S. flight program, LMSC recently demonstrated a welded lightweight array system using both 2 x 4 and 5.9 x 5.9 cm wraparound solar cells. This weld system uses infrared sensing of weld joint temperature at the cell contact metalization interface to precisely control weld energy on each joint. Modules fabricated using this weld control system survived lowearth-orbit simulated 5-year tests (over 30,000 cycles) without joint failure. The data from these specifically configured modules, printed circuit substrate with copper interconnect and dielectric wraparound solar cells, can be used as a basis for developing weld schedules for additional cell array panel types.

  16. Heteroepitaxially grown InP solar cells

    International Nuclear Information System (INIS)

    Weinberg, I.; Swartz, C.K.; Brinker, D.J.; Wilt, D.M.

    1990-01-01

    Although they are significantly more radiation resistant than either Si or GaAs solar cells, their high wafer cost presents a barrier to the widespread use of InP solar cells in space. For this reason, the authors have initiated a program aimed at producing high efficiency, radiation resistant solar cells processed from InP heteroepitaxially grown on cheaper substrates. The authors' objective is to present the most recent results emanating from this program together with the results of their initial proton irradiations on these cells. This paper reports that InP cells were processed from a 4 micron layer of InP, grown by OMCVD on a silicon substrate, with a 0.5 micron buffer layer between the InP directly grown on a GaAs substrate. Initial feasibility studies, in a Lewis sponsored program at the Spire corporation, resulted in air mass zero efficiencies of 7.1% for the former cells and 9.1% for the latter. These initial low efficiencies are attributed to the high dislocation densities caused by lattice mismatch. The authors' preirradiation analysis indicates extremely low minority carrier diffusion lengths, in both cell base and emitter, and high values of both the diffusion and recombination components of the diode reverse saturation currents. Irradiation by 10 MeV protons, to a fluence of 10 13 cm -2 , resulted in relatively low degradation in cell efficiency, short circuit current and open circuit voltage

  17. Full space device optimization for solar cells.

    Science.gov (United States)

    Baloch, Ahmer A B; Aly, Shahzada P; Hossain, Mohammad I; El-Mellouhi, Fedwa; Tabet, Nouar; Alharbi, Fahhad H

    2017-09-20

    Advances in computational materials have paved a way to design efficient solar cells by identifying the optimal properties of the device layers. Conventionally, the device optimization has been governed by single or double descriptors for an individual layer; mostly the absorbing layer. However, the performance of the device depends collectively on all the properties of the material and the geometry of each layer in the cell. To address this issue of multi-property optimization and to avoid the paradigm of reoccurring materials in the solar cell field, a full space material-independent optimization approach is developed and presented in this paper. The method is employed to obtain an optimized material data set for maximum efficiency and for targeted functionality for each layer. To ensure the robustness of the method, two cases are studied; namely perovskite solar cells device optimization and cadmium-free CIGS solar cell. The implementation determines the desirable optoelectronic properties of transport mediums and contacts that can maximize the efficiency for both cases. The resulted data sets of material properties can be matched with those in materials databases or by further microscopic material design. Moreover, the presented multi-property optimization framework can be extended to design any solid-state device.

  18. Development of Inorganic Solar Cells by Nano-technology

    Institute of Scientific and Technical Information of China (English)

    Yafei Zhang; HueyLiang Hwang; Huijuan Geng; Zhihua Zhou; Jiang Wu; Zhiming Wang; Yaozhong Zhang; Zhongli Li; Liying Zhang; Zhi Yang

    2012-01-01

    Inorganic solar cells, as durable photovoltaic devices for harvesting electric energy from sun light, have received tremendous attention due to the fear of exhausting the earth’s energy resources and damaging the living environment due to greenhouse gases. Some recent developments in nanotechnology have opened up new avenues for more relevant inorganic solar cells produced by new photovoltaic conversion concepts and effective solar energy harvesting nanostructures. In this review, the multiple exciton generation effect solar cells, hot carrier solar cells, one dimensional material constructed asymmetrical schottky barrier arrays, noble nanoparticle induced plasmonic enhancement, and light trapping nanostructured semiconductor solar cells are highlighted.

  19. Photonic crystal geometry for organic solar cells.

    Science.gov (United States)

    Ko, Doo-Hyun; Tumbleston, John R; Zhang, Lei; Williams, Stuart; DeSimone, Joseph M; Lopez, Rene; Samulski, Edward T

    2009-07-01

    We report organic solar cells with a photonic crystal nanostructure embossed in the photoactive bulk heterojunction layer, a topography that exhibits a 3-fold enhancement of the absorption in specific regions of the solar spectrum in part through multiple excitation resonances. The photonic crystal geometry is fabricated using a materials-agnostic process called PRINT wherein highly ordered arrays of nanoscale features are readily made in a single processing step over wide areas (approximately 4 cm(2)) that is scalable. We show efficiency improvements of approximately 70% that result not only from greater absorption, but also from electrical enhancements. The methodology is generally applicable to organic solar cells and the experimental findings reported in our manuscript corroborate theoretical expectations.

  20. Colloidal quantum dot solar cells exploiting hierarchical structuring

    KAUST Repository

    Labelle, André J.; Thon, Susanna; Masala, Silvia; Adachi, Michael M.; Dong, Haopeng; Farahani, Maryam; Ip, Alexander H.; Fratalocchi, Andrea; Sargent, E. H.

    2015-01-01

    Extremely thin-absorber solar cells offer low materials utilization and simplified manufacture but require improved means to enhance photon absorption in the active layer. Here, we report enhanced-absorption colloidal quantum dot (CQD) solar cells

  1. Generalized detailed balance theory of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Kirchartz, Thomas

    2009-12-12

    The principle of detailed balance is the requirement that every microscopic process in a system must be in equilibrium with its inverse process, when the system itself is in thermodynamic equilibrium. This detailed balance principle has been of special importance for photovoltaics, since it allows the calculation of the limiting efficiency of a given solar cell by defining the only fundamental loss process as the radiative recombination of electron/hole pairs followed by the emission of a photon. In equilibrium, i.e. in the dark and without applied voltage, the absorbed and emitted photon flux must be equal due to detailed balance. This equality determines the radiative recombination from absorption and vice versa. While the classical theory of photovoltaic efficiency limits by Shockley and Queisser considers only one detailed balance pair, namely photogeneration and radiative recombination, the present work extends the detailed balance principle to any given process in the solar cell. Applying the detailed balance principle to the whole device leads to two major results, namely (i) a model that is compatible with the Shockley-Queisser efficiency limit for efficient particle transport, while still being able to describe non-ideal and non-linear solar cells, and (ii) an analytical relation between electroluminescent emission and photovoltaic action of a diode that is applied to a variety of different solar cells. This thesis presents several variations of a detailed balance model that are applicable to different types of solar cells. Any typical inorganic solar cell is a mainly bipolar device, meaning that the current is carried by electrons and holes. The detailed balance model for pn-type and pin-type bipolar solar cells is therefore the most basic incorporation of a detailed balance model. The only addition compared to the classical diode theory or compared to standard one-dimensional device simulators is the incorporation of photon recycling, making the model

  2. Charge-carrier transport and recombination in heteroepitaxial CdTe

    International Nuclear Information System (INIS)

    Kuciauskas, Darius; Farrell, Stuart; Dippo, Pat; Moseley, John; Moutinho, Helio; Li, Jian V.; Allende Motz, A. M.; Kanevce, Ana; Zaunbrecher, Katherine; Gessert, Timothy A.; Levi, Dean H.; Metzger, Wyatt K.; Colegrove, Eric; Sivananthan, S.

    2014-01-01

    We analyze charge-carrier dynamics using time-resolved spectroscopy and varying epitaxial CdTe thickness in undoped heteroepitaxial CdTe/ZnTe/Si. By employing one-photon and nonlinear two-photon excitation, we assess surface, interface, and bulk recombination. Two-photon excitation with a focused laser beam enables characterization of recombination velocity at the buried epilayer/substrate interface, 17.5 μm from the sample surface. Measurements with a focused two-photon excitation beam also indicate a fast diffusion component, from which we estimate an electron mobility of 650 cm 2 (Vs) −1 and diffusion coefficient D of 17 cm 2  s −1 . We find limiting recombination at the epitaxial film surface (surface recombination velocity S surface  = (2.8 ± 0.3) × 10 5  cm s −1 ) and at the heteroepitaxial interface (interface recombination velocity S interface  = (4.8 ± 0.5) × 10 5  cm s −1 ). The results demonstrate that reducing surface and interface recombination velocity is critical for photovoltaic solar cells and electronic devices that employ epitaxial CdTe.

  3. Hybrid nanocrystal/polymer solar cells based on tetrapod-shaped CdSexTe1-x nanocrystals

    International Nuclear Information System (INIS)

    Zhou Yi; Li Yunchao; Zhong Haizheng; Hou Jianhui; Ding Yuqin; Yang Chunhe; Li Yongfang

    2006-01-01

    A series of ternary tetrapodal nanocrystals of CdSe x Te 1-x with x = 0 (CdTe), 0.23, 0.53, 0.78, 1 (CdSe) were synthesized and used to fabricate hybrid nanocrystal/polymer solar cells. Herein, the nanocrystals acted as electron acceptors, and poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) was used as an electron donor. It was found that the open circuit voltage (V oc ), short-circuit current (J sc ) and power conversion efficiency (η) of the devices all increased with increasing Se content in the CdSe x Te 1-x nanocrystals under identical experimental conditions. The solar cell based on the blend of tetrapodal CdSe nanocrystals and MEH-PPV (9:1 w/w) showed the highest power conversion efficiency of 1.13% under AM 1.5, 80 mW cm -2 , and the maximum incident photon to converted current efficiency (IPCE) of the device reached 47% at 510 nm. The influence of nanocrystal composition on the photovoltaic properties of the hybrid solar cells was explained by the difference of the band level positions between MEH-PPV and the nanocrystals

  4. Doctor Blade-Coated Polymer Solar Cells

    KAUST Repository

    Cho, Nam Chul; Kim, Jong H.

    2016-01-01

    In this work, we report polymer solar cells based on blade-coated P3HT:PC71BM and PBDTTT-EFT:PC71BM bulk heterojunction photoactive layers. Enhanced power conversion efficiency of 2.75 (conventional structure) and 3.03% (inverted structure

  5. Baselines for Lifetime of Organic Solar Cells

    DEFF Research Database (Denmark)

    Gevorgyan, Suren; Espinosa Martinez, Nieves; Ciammaruchi, Laura

    2016-01-01

    The process of accurately gauging lifetime improvements in organic photovoltaics (OPVs) or other similar emerging technologies, such as perovskites solar cells is still a major challenge. The presented work is part of a larger effort of developing a worldwide database of lifetimes that can help...

  6. Film adhesion in amorphous silicon solar cells

    Indian Academy of Sciences (India)

    TECS

    Film adhesion in amorphous silicon solar cells. A R M YUSOFF*, M N SYAHRUL and K HENKEL. Malaysia Energy Centre, 8th Floor, North Wing, Sapura @ Mines, 7, Jalan Tasik, The Mines Resort City,. 43300 Seri Kembangan, Selangor Darul Ehsan. MS received 11 April 2007. Abstract. A major issue encountered ...

  7. Electrical Characterization of HIT type solar cells

    NARCIS (Netherlands)

    Rath, J.K.

    2012-01-01

    The silicon heterojunction solar cell (SHJ) has made rapid progress in reaching high efficiency and it is already developed as an industrially viable product. However, much of its progress has come through process development while there is scarce knowledge on the microscopic nature of the

  8. Characterization of HIT type solar cells

    NARCIS (Netherlands)

    Rath, J.K.

    2011-01-01

    The silicon heterojunction solar cell (SHJ) has made rapid progress in reaching high efficiency and it is already developed as an industrially viable product. However, much of its progress has come through process development while there is scarce knowledge on the microscopic nature of the

  9. Fullerenes and nanostructured plastic solar cells

    NARCIS (Netherlands)

    Knol, Joop; Hummelen, Jan C.; Kuzmany, H; Fink, J; Mehring, M; Roth, S

    1998-01-01

    We report on the present on the present status of the plastic solar cell and on the design of fullerene derivatives and pi-conjugated donor molecules that can function as acceptor-donor pairs and (supra-) molecular building blocks in organized, nanostructured interpenetrating networks, forming a

  10. Photochromic dye-sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Noah M. Johnson

    2015-11-01

    Full Text Available We report the fabrication and characterization of photochromic dye sensitized solar cells that possess the ability to change color depending on external lighting conditions. This device can be used as a “smart” window shade that tints, collects the sun's energy, and blocks sunlight when the sun shines, and is completely transparent at night.

  11. Hybrid Silicon Nanocone–Polymer Solar Cells

    KAUST Repository

    Jeong, Sangmoo

    2012-06-13

    Recently, hybrid Si/organic solar cells have been studied for low-cost Si photovoltaic devices because the Schottky junction between the Si and organic material can be formed by solution processes at a low temperature. In this study, we demonstrate a hybrid solar cell composed of Si nanocones and conductive polymer. The optimal nanocone structure with an aspect ratio (height/diameter of a nanocone) less than two allowed for conformal polymer surface coverage via spin-coating while also providing both excellent antireflection and light trapping properties. The uniform heterojunction over the nanocones with enhanced light absorption resulted in a power conversion efficiency above 11%. Based on our simulation study, the optimal nanocone structures for a 10 μm thick Si solar cell can achieve a short-circuit current density, up to 39.1 mA/cm 2, which is very close to the theoretical limit. With very thin material and inexpensive processing, hybrid Si nanocone/polymer solar cells are promising as an economically viable alternative energy solution. © 2012 American Chemical Society.

  12. Solar Cell Efficiency Tables (Version 51)

    Energy Technology Data Exchange (ETDEWEB)

    Levi, Dean H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Green, Martin A. [University of New South Wales; Hishikawa, Yoshihiro [National Institute of Advanced Industrial Science and Technology (AIST); Dunlop, Ewan D. [European Commission-Joint Research Centre; Hohl-Ebinger, Jochen [Fraunhofer Institute for Solar Energy Systems; Ho-Baillie, Anita W. Y. [University of New South Wales

    2017-12-14

    Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2017 are reviewed, together with progress over the last 25 years. Appendices are included documenting area definitions and also listing recognised test centres.

  13. Distributed series resistance effects in solar cells

    DEFF Research Database (Denmark)

    Nielsen, Lars Drud

    1982-01-01

    A mathematical treatment is presented of the effects of one-dimensional distributed series resistance in solar cells. A general perturbation theory is developed, including consistently the induced spatial variation of diode current density and leading to a first-order equivalent lumped resistance...

  14. Hybrid solar cells : Perovskites under the Sun

    NARCIS (Netherlands)

    Loi, Maria Antonietta; Hummelen, Jan C.

    2013-01-01

    Mixed-halide organic–inorganic hybrid perovskites are reported to display electron–hole diffusion lengths over 1 μm. This observation provides important insight into the charge-carrier dynamics of this class of semiconductors and increases the expectations for highly efficient and cheap solar cells.

  15. Energy. From firewood to solar cell

    International Nuclear Information System (INIS)

    Reijnders, L.

    2006-01-01

    An outline is given of the development of energy and the options to secure the energy supply for the future. Much information is given about energy efficiency, the exploitation of tar sands, reopening of the coal mines in the Netherlands, nuclear fusion and fission, wave energy and solar cells, etc [nl

  16. Fuel Cell / electrolyser, Solar Photovoltaic Powered

    Directory of Open Access Journals (Sweden)

    Chioncel Cristian Paul

    2012-01-01

    Full Text Available The paper presents experimental obtained results in the operation ofelectrolyzer powered by solar photovoltaic modules, for the waterelectrolysis and with the obtained hydrogen and oxygen proceeds tothe operation in fuel cell mode, type PEM. The main operatingparameters and conditions to optimize the energy conversion on thesolar-hydrogen-electricity cycle are highlighted, so that those arecomparable or superior to conventional cycles.

  17. Numerical simulation model of multijunction solar cell

    NARCIS (Netherlands)

    Babar, M.; Al-Ammar, E.A.; Malik, N.H.

    2012-01-01

    Multi-junction solar cells play an important and significant role in the Concentrated Photovoltaic (CPV) Systems. Recent developments in Concentrated Photovoltaic concerning high power production and cost effective- ness along with better efficiency are due to the advancements in multi-junction

  18. Solar cells for space applications (part 2)

    International Nuclear Information System (INIS)

    Gomez, T.J.

    1992-01-01

    This lecture focusses on qualification and verification tests and procedures on solar cells designed for space applications. The series of tests should produce orbital performance under determined illumination, temperature and irradiance. Tests are divided in outdoor and laboratory experiments. Environmental tests include durability, qualification (mechanical and electrical), I-V curves, Spectral response

  19. Hybrid Silicon Nanocone–Polymer Solar Cells

    KAUST Repository

    Jeong, Sangmoo; Garnett, Erik C.; Wang, Shuang; Yu, Zongfu; Fan, Shanhui; Brongersma, Mark L.; McGehee, Michael D.; Cui, Yi

    2012-01-01

    Recently, hybrid Si/organic solar cells have been studied for low-cost Si photovoltaic devices because the Schottky junction between the Si and organic material can be formed by solution processes at a low temperature. In this study, we demonstrate a hybrid solar cell composed of Si nanocones and conductive polymer. The optimal nanocone structure with an aspect ratio (height/diameter of a nanocone) less than two allowed for conformal polymer surface coverage via spin-coating while also providing both excellent antireflection and light trapping properties. The uniform heterojunction over the nanocones with enhanced light absorption resulted in a power conversion efficiency above 11%. Based on our simulation study, the optimal nanocone structures for a 10 μm thick Si solar cell can achieve a short-circuit current density, up to 39.1 mA/cm 2, which is very close to the theoretical limit. With very thin material and inexpensive processing, hybrid Si nanocone/polymer solar cells are promising as an economically viable alternative energy solution. © 2012 American Chemical Society.

  20. Passivated emitters in silicon solar cells

    International Nuclear Information System (INIS)

    King, R.R.; Gruenbaum, P.E.; Sinton, R.A.; Swanson, R.M.

    1990-01-01

    In high-efficiency silicon solar cells with low metal contact coverage fractions and high bulk lifetimes, cell performance is often dominated by recombination in the oxide-passivated diffusions on the cell surface. Measurements of the emitter saturation current density, J o , of oxide-passivated, boron and phosphorus diffusions are presented, and from these measurements, the dependence of surface recombination velocity on dopant concentration was extracted. The lowest observed values of J o which are stable under UV light are given for both boron- and phosphorus-doped, oxide-passivated diffusions, for both textured and untextured surfaces. Contour plots which incorporate the above data have been applied to two types of backside-contact solar cells with large area (37.5 cm 2 ) and one-sun efficiencies up to 22.7%

  1. Diketopyrrolopyrrole Polymers for Organic Solar Cells.

    Science.gov (United States)

    Li, Weiwei; Hendriks, Koen H; Wienk, Martijn M; Janssen, René A J

    2016-01-19

    Conjugated polymers have been extensively studied for application in organic solar cells. In designing new polymers, particular attention has been given to tuning the absorption spectrum, molecular energy levels, crystallinity, and charge carrier mobility to enhance performance. As a result, the power conversion efficiencies (PCEs) of solar cells based on conjugated polymers as electron donor and fullerene derivatives as electron acceptor have exceeded 10% in single-junction and 11% in multijunction devices. Despite these efforts, it is notoriously difficult to establish thorough structure-property relationships that will be required to further optimize existing high-performance polymers to their intrinsic limits. In this Account, we highlight progress on the development and our understanding of diketopyrrolopyrrole (DPP) based conjugated polymers for polymer solar cells. The DPP moiety is strongly electron withdrawing and its polar nature enhances the tendency of DPP-based polymers to crystallize. As a result, DPP-based conjugated polymers often exhibit an advantageously broad and tunable optical absorption, up to 1000 nm, and high mobilities for holes and electrons, which can result in high photocurrents and good fill factors in solar cells. Here we focus on the structural modifications applied to DPP polymers and rationalize and explain the relationships between chemical structure and organic photovoltaic performance. The DPP polymers can be tuned via their aromatic substituents, their alkyl side chains, and the nature of the π-conjugated segment linking the units along the polymer chain. We show that these building blocks work together in determining the molecular conformation, the optical properties, the charge carrier mobility, and the solubility of the polymer. We identify the latter as a decisive parameter for DPP-based organic solar cells because it regulates the diameter of the semicrystalline DPP polymer fibers that form in the photovoltaic blends with

  2. How the relative permittivity of solar cell materials influences solar cell performance

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Huss-Hansen, Mathias K.; Hansen, Ole

    2017-01-01

    of the materials permittivity on the physics and performance of the solar cell by means of numerical simulation supported by analytical relations. We demonstrate that, depending on the specific solar cell configuration and materials properties, there are scenarios where the relative permittivity has a major......The relative permittivity of the materials constituting heterojunction solar cells is usually not considered as a design parameter when searching for novel combinations of heterojunction materials. In this work, we investigate the validity of such an approach. Specifically, we show the effect...... the heterojunction partner has a high permittivity, solar cells are consistently more robust against several non-idealities that are especially likely to occur in early-stage development, when the device is not yet optimized....

  3. Nanocluster production for solar cell applications

    International Nuclear Information System (INIS)

    Al Dosari, Haila M.; Ayesh, Ahmad I.

    2013-01-01

    This research focuses on the fabrication and characterization of silver (Ag) and silicon (Si) nanoclusters that might be used for solar cell applications. Silver and silicon nanoclusters have been synthesized by means of dc magnetron sputtering and inert gas condensation inside an ultra-high vacuum compatible system. We have found that nanocluster size distributions can be tuned by various source parameters, such as the sputtering discharge power, flow rate of argon inert gas, and aggregation length. Quadrupole mass filter and transmission electron microscopy were used to evaluate the size distribution of Ag and Si nanoclusters. Ag nanoclusters with average size in the range of 3.6–8.3 nm were synthesized (herein size refers to the nanocluster diameter), whereas Si nanoclusters' average size was controlled to range between 2.9 and 7.4 nm by controlling the source parameters. This work illustrates the ability of controlling the Si and Ag nanoclusters' sizes by proper optimization of the operation conditions. By controlling nanoclusters' sizes, one can alter their surface properties to suit the need to enhance solar cell efficiency. Herein, Ag nanoclusters were deposited on commercial polycrystalline solar cells. Short circuit current (I SC ), open circuit voltage (V OC ), fill factor, and efficiency (η) were obtained under light source with an intensity of 30 mW/cm 2 . A 22.7% enhancement in solar cell efficiency could be measured after deposition of Ag nanoclusters, which demonstrates that Ag nanoclusters generated in this work are useful to enhance solar cell efficiency

  4. Solar cell radiation handbook. Addendum 1: 1982-1988

    International Nuclear Information System (INIS)

    Anspaugh, B.E.

    1989-02-01

    The Solar Cell Radiation Handbook (JPL Publication 82-69) is updated. In order to maintain currency of solar cell radiation data, recent solar cell designs have been acquired, irradiated with 1 MeV electrons, and measured. The results of these radiation experiments are reported

  5. NREL Solar Cell Wins Federal Technology Transfer Prize | News | NREL

    Science.gov (United States)

    Solar Cell Wins Federal Technology Transfer Prize News Release: NREL Solar Cell Wins Federal Technology Transfer Prize May 7, 2009 A new class of ultra-light, high-efficiency solar cells developed by the U.S. Department of Energy's National Renewable Energy Laboratory has been awarded a national prize

  6. Flexible thermal cycle test equipment for concentrator solar cells

    Science.gov (United States)

    Hebert, Peter H [Glendale, CA; Brandt, Randolph J [Palmdale, CA

    2012-06-19

    A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

  7. A cost roadmap for silicon heterojunction solar cells

    NARCIS (Netherlands)

    Louwen, A.; van Sark, W.; Schropp, R.E.I.; Faaij, A.

    2016-01-01

    Research and development of silicon heterojunction (SHJ) solar cells has seen a marked increase since the recent expiry of core patents describing SHJ technology. SHJ solar cells are expected to offer various cost benefits compared to conventional crystalline silicon solar cells. This paper analyses

  8. A Cost Roadmap for Silicon Heterojunction Solar Cells

    NARCIS (Netherlands)

    Louwen, A.; van Sark, W.G.J.H.M.; Schropp, Ruud; Faaij, A.

    Research and development of silicon heterojunction (SHJ) solar cells has seen a marked increase since the recent expiry of core patents describing SHJ technology. SHJ solar cells are expected to offer various cost benefits compared to conventional crystalline silicon solar cells. This paper analyses

  9. High-efficient solar cells with porous silicon

    International Nuclear Information System (INIS)

    Migunova, A.A.

    2002-01-01

    It has been shown that the porous silicon is multifunctional high-efficient coating on silicon solar cells, modifies its surface and combines in it self antireflection and passivation properties., The different optoelectronic effects in solar cells with porous silicon were considered. The comparative parameters of uncovered photodetectors also solar cells with porous silicon and other coatings were resulted. (author)

  10. C-Si solar cell modules

    International Nuclear Information System (INIS)

    Tomita, Takashi

    2005-01-01

    In order to meet the rapidly growing demand for solar power photovoltaic systems which is based on public consciousness of global environmental issues, SHARP has increased the production of solar cells and modules over 10-fold in the last 5 years. Silicon-based technologies are expected to be dominant in the coming decade. In the course of an increase of the annual production scale to 1000 MW, the efficiency of modules will be improved and the thickness of wafers will be decreased and all this will lead to a drastic price reduction of PV systems. (Author)

  11. Unified Numerical Solver for Device Metastabilities in CdTe Thin-Film PV

    Energy Technology Data Exchange (ETDEWEB)

    Vasileska, Dragica [Arizona State Univ., Tempe, AZ (United States)

    2017-08-17

    Thin-film modules of all technologies often suffer from performance degradation over time. Some of the performance changes are reversible and some are not, which makes deployment, testing, and energy-yield prediction more challenging. Manufacturers de-vote significant empirical efforts to study these phenomena and to improve semiconduc-tor device stability. Still, understanding the underlying reasons of these instabilities re-mains clouded due to the lack of ability to characterize materials at atomistic levels and the lack of interpretation from the most fundamental material science. The most com-monly alleged causes of metastability in CdTe device, such as “migration of Cu,” have been investigated rigorously over the past fifteen years. Still, the discussion often ended prematurely with stating observed correlations between stress conditions and changes in atomic profiles of impurities or CV doping concentration. Multiple hypotheses sug-gesting degradation of CdTe solar cell devices due to interaction and evolution of point defects and complexes were proposed, and none of them received strong theoretical or experimental confirmation. It should be noted that atomic impurity profiles in CdTe pro-vide very little intelligence on active doping concentrations. The same elements could form different energy states, which could be either donors or acceptors, depending on their position in crystalline lattice. Defects interact with other extrinsic and intrinsic de-fects; for example, changing the state of an impurity from an interstitial donor to a sub-stitutional acceptor often is accompanied by generation of a compensating intrinsic in-terstitial donor defect. Moreover, all defects, intrinsic and extrinsic, interact with the elec-trical potential and free carriers so that charged defects may drift in the electric field and the local electrical potential affects the formation energy of the point defects. Such complexity of interactions in CdTe makes understanding of

  12. Characterisation of multicrystalline solar cells

    OpenAIRE

    A.Q. Malik; Chong Chew Hah; Chan Siang Khwang; Lim Chee Ming; Tan Kha Sheng

    2017-01-01

    The evaluation and assessment of the performance of photovoltaic (PV) cells in terms of measurable parameters requires the measurement of the current as a function of voltage, temperature, intensity, wind speed and spectrum. Mo st noticeable of all these parameters is the PV conversion efficiency η, defined as the maximum electrical power Pmax produced by the PV cell divided by the incident photon power P in which is measured with respect to standard test conditions (STC). These conditions re...

  13. Fabrication of transparent TiO2 nanotube-based photoanodes for CdS/CdTe quantum co-sensitized solar cells

    Science.gov (United States)

    Gualdrón-Reyes, A. F.; Cárdenas-Arenas, A.; Martínez, C. A.; Kouznetsov, V. V.; Meléndez, A. M.

    2017-01-01

    In order to fabricate a solar cell, ordered TiO2 nanotube (TNT) arrays were prepared by double anodization. TNT arrays with variable lengths were obtained by changing the duration of the anodizing process of up to 3h. TNT membranes were transferred to indium tin oxide substrates and attached with a B-TiO2 sol. TNT photoanode with the best photoelectrochemical performance was sensitized with CdS by SILAR method. On other hand, CdTe quantum dots prepared via colloidal synthesis were deposited on TNT photoanodes for 2h, 4h and 6h. In addition, TNT/CdS was loaded with CdTe quantum dots for 4 h. Morphology and chemical modification of TiO2 were characterized by FESEM and XPS, while their photoelectrochemical performance was measured by open-circuit photopotential and photovoltammetry under visible light. TiO2 nanotubes grown during 2.5h showed the highest photocurrent due to presence of Ti3+ donor states by N and F co-doping, increasing the number of photogenerated electrons transported to back collector. TNT/CdS/CdTe photoanode reach the highest conversion efficiency under AM 1.5G simulated solar illumination.

  14. Influence of CdCl{sub 2} activation treatment on ultra-thin Cd{sub 1−x}Zn{sub x}S/CdTe solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, A.J., E-mail: a.clayton@glyndwr.ac.uk [Centre for Solar Energy Research, Glyndŵr University, OpTIC, St. Asaph LL17 0JD (United Kingdom); Baker, M.A.; Babar, S. [Faculty of Engineering & Physical Sciences, University of Surrey, Guildford GU2 7XH (United Kingdom); Gibson, P.N. [Institute for Health & Consumer Protection, Joint Research Centre, 21020 Ispra, VA (Italy); Irvine, S.J.C.; Kartopu, G.; Lamb, D.A.; Barrioz, V. [Centre for Solar Energy Research, Glyndŵr University, OpTIC, St. Asaph LL17 0JD (United Kingdom)

    2015-09-01

    Ultra-thin CdTe photovoltaic solar cells with an absorber thickness of 0.5 μm were produced by metal organic chemical vapour deposition onto indium tin oxide coated boroaluminosilicate glass. A wide band gap Cd{sub 1−x}Zn{sub x}S alloy window layer was employed to improve spectral response in the blue region of the solar spectrum. X-ray photoelectron spectroscopy, X-ray diffraction and scanning electron microscopy were used to monitor changes in the chemical composition and microstructure of the Cd{sub 1−x}Zn{sub x}S/CdTe solar cell after varying the post-deposition CdCl{sub 2} activation treatment time and annealing temperature. The CdCl{sub 2} treatment leached Zn from the Cd{sub 1−x}Zn{sub x}S layer causing a redshift in the spectral response onset of window absorption. S diffusion occurred across the Cd{sub 1−x}Zn{sub x}S/CdTe interface, which was more pronounced as the CdCl{sub 2} treatment was increased. A CdTe{sub 1−y}S{sub y} alloy was formed at the interface, which thickened with CdCl{sub 2} treatment time. Small concentrations of S (up to 2 at.%) were observed throughout the CdTe layer as the degree of CdCl{sub 2} treatment was increased. Greater S diffusion across the Cd{sub 1−x}Zn{sub x}S/CdTe interface caused the device open-circuit voltage (V{sub oc}) to increase. The higher V{sub oc} is attributed to enhanced strain relaxation and associated reduction of defects in the interface region as well as the increase in CdTe grain size. - Highlights: • Increased CdCl{sub 2} activation treatment resulted in loss of Zn from Cd{sub 1−x}Zn{sub x}S. • Sulphur diffusion into CdTe was enhanced with greater CdCl{sub 2} activation treatment. • Improvement to V{sub oc} correlated with increased sulphur diffusion into CdTe.

  15. Laser scanning of experimental solar cells

    Science.gov (United States)

    Plunkett, B. C.; Lasswell, P. G.

    1980-01-01

    A description is presented of a laser scanning instrument which makes it possible to display and measure the spatial response of a solar cell. Examples are presented to illustrate the use of generated micrographs in the isolation of flaws and features of the cell. The laser scanner system uses a 4 mW, CW helium-neon laser, operating a wavelength of 0.633 micrometers. The beam is deflected by two mirror galvanometers arranged to scan in orthogonal directions. After being focused on the solar cell by the beam focusing lens, the moving light spot raster scans the specimen. The current output of the photovoltaic device under test, as a function of the scan dot position, can be displayed in several modes. The laser scanner has proved to be a very useful diagnostic tool in optimizing the process design of transparent metal film photovoltaic devices on Zn3P2, a relatively new photovoltaic material.

  16. TRANSPARENT COATINGS FOR SOLAR CELLS RESEARCH

    Energy Technology Data Exchange (ETDEWEB)

    Glatkowski, P. J.; Landis, D. A.

    2013-04-16

    Todays solar cells are fabricated using metal oxide based transparent conductive coatings (TCC) or metal wires with optoelectronic performance exceeding that currently possible with Carbon Nanotube (CNT) based TCCs. The motivation for replacing current TCC is their inherent brittleness, high deposition cost, and high deposition temperatures; leading to reduced performance on thin substrates. With improved processing, application and characterization techniques Nanofiber and/or CNT based TCCs can overcome these shortcomings while offering the ability to be applied in atmospheric conditions using low cost coating processes At todays level of development, CNT based TCC are nearing commercial use in touch screens, some types of information displays (i.e. electronic paper), and certain military applications. However, the resistivity and transparency requirements for use in current commercial solar cells are more stringent than in many of these applications. Therefore, significant research on fundamental nanotube composition, dispersion and deposition are required to reach the required performance commanded by photovoltaic devices. The objective of this project was to research and develop transparent conductive coatings based on novel nanomaterial composite coatings, which comprise nanotubes, nanofibers, and other nanostructured materials along with binder materials. One objective was to show that these new nanomaterials perform at an electrical resistivity and optical transparency suitable for use in solar cells and other energy-related applications. A second objective was to generate new structures and chemistries with improved resistivity and transparency performance. The materials also included the binders and surface treatments that facilitate the utility of the electrically conductive portion of these composites in solar photovoltaic devices. Performance enhancement venues included: CNT purification and metallic tube separation techniques, chemical doping, CNT

  17. Solar Airplanes and Regenerative Fuel Cells

    Science.gov (United States)

    Bents, David J.

    2007-01-01

    A solar electric aircraft with the potential to "fly forever" has captured NASA's interest, and the concept for such an aircraft was pursued under Aeronautics Environmental Research Aircraft and Sensor Technology (ERAST) project. Feasibility of this aircraft happens to depend on the successful development of solar power technologies critical to NASA's Exploration Initiatives; hence, there was widespread interest throughout NASA to bring these technologies to a flight demonstration. The most critical is an energy storage system to sustain mission power during night periods. For the solar airplane, whose flight capability is already limited by the diffuse nature of solar flux and subject to latitude and time of year constraints, the feasibility of long endurance flight depends on a storage density figure of merit better than 400-600 watt-hr per kilogram. This figure of merit is beyond the capability of present day storage technologies (other than nuclear) but may be achievable in the hydrogen-oxygen regenerative fuel cell (RFC). This potential has led NASA to undertake the practical development of a hydrogen-oxygen regenerative fuel cell, initially as solar energy storage for a high altitude UAV science platform but eventually to serve as the primary power source for NASAs lunar base and other planet surface installations. Potentially the highest storage capacity and lowest weight of any non-nuclear device, a flight-weight RFC aboard a solar-electric aircraft that is flown continuously through several successive day-night cycles will provide the most convincing demonstration that this technology's widespread potential has been realized. In 1998 NASA began development of a closed cycle hydrogen oxygen PEM RFC under the Aeronautics Environmental Research Aircraft and Sensor Technology (ERAST) project and continued its development, originally for a solar electric airplane flight, through FY2005 under the Low Emissions Alternative Power (LEAP) project. Construction of

  18. BODIPYs for Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Klfout, Hafsah; Stewart, Adam; Elkhalifa, Mahmoud; He, Hongshan

    2017-11-22

    BODIPY, abbreviation of boron-dipyrromethene, is one class of robust organic molecules that has been used widely in bioimaging, sensing, and logic gate design. Recently, BODIPY dyes have been explored for dye-sensitized solar cells (DSCs). Studies demonstrate their potential as light absorbers for the conversion of solar energy to electricity. However, their photovoltaic performance is inferior to many other dyes, including porphyrin dyes. In this review, several synthetic strategies of BODIPY dyes for DSCs and their further functionalization are described. The photophysical properties of dye molecules and their photovoltaic performances in DSCs are summarized. We aim to provide readers a clear picture of the field and expect to shed light on the next generation of BODIPY dyes for their applications in solar energy conversion.

  19. Proton irradiation effects of amorphous silicon solar cell for solar power satellite

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Yousuke; Oshima, Takeshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Sasaki, Susumu; Kuroda, Hideo; Ushirokawa, Akio

    1997-03-01

    Flexible amorphous silicon(fa-Si) solar cell module, a thin film type, is regarded as a realistic power generator for solar power satellite. The radiation resistance of fa-Si cells was investigated by the irradiations of 3,4 and 10 MeV protons. The hydrogen gas treatment of the irradiated fa-Si cells was also studied. The fa-Si cell shows high radiation resistance for proton irradiations, compared with a crystalline silicon solar cell. (author)

  20. Solar Cell Production in Nigeria: Prospects, Options and Problems

    International Nuclear Information System (INIS)

    Fasasi, A. Y.; Siyanbola, W.O.; Ibitoye, F. I.; Pelemo, D. A.

    2002-01-01

    The prospects and problems facing solar cell production in Nigeria are discussed. The paper reviews many proven solar cell materials in terms of their current efficiencies and production costs. Silicon solar cell production appears to be the best technology option for Nigeria because of the abundant quartz sand and waste products from our phosphate fertiliser company that can be employed as starting materials to produce solar grade silicon. Factors affecting solar cell efficiency, choice of solar cell as well as financial and material problems limiting the progress on silicon solar cell production are also discussed. Finally, the paper recommends the simultaneous production of solar grade silicon and coordinated development of the balance of system components as first steps towards actualizing this objective

  1. Type conversion, contacts, and surface effects in electroplated CdTe films

    International Nuclear Information System (INIS)

    Basol, B.M.; Ou, S.S.; Stafsudd, O.M.

    1985-01-01

    Efficient electroplated CdS/CdTe solar cells can be fabricated by heat treating and type-converting the n-CdTe films deposited on CdS layers. In this paper, various mechanisms which may give rise to the conversion of electroplated CdTe films from n to p type are investigated. It is concluded that Cd-vacancy generation is the main mechanism of type conversion. Possible effects of oxygen on this mechanism are also discussed. Evaporated Au contacts to electroplated p-CdTe films were studied. It was found that the Au contacts depleted the excess Te present on the surface of Br 2 -methanol etched p-CdTe films. Oxygen was found to affect the electrical characteristics of such contacts

  2. Semiconductor Nanocrystals as Light Harvesters in Solar Cells

    Directory of Open Access Journals (Sweden)

    Lioz Etgar

    2013-02-01

    Full Text Available Photovoltaic cells use semiconductors to convert sunlight into electrical current and are regarded as a key technology for a sustainable energy supply. Quantum dot-based solar cells have shown great potential as next generation, high performance, low-cost photovoltaics due to the outstanding optoelectronic properties of quantum dots and their multiple exciton generation (MEG capability. This review focuses on QDs as light harvesters in solar cells, including different structures of QD-based solar cells, such as QD heterojunction solar cells, QD-Schottky solar cells, QD-sensitized solar cells and the recent development in organic-inorganic perovskite heterojunction solar cells. Mechanisms, procedures, advantages, disadvantages and the latest results obtained in the field are described. To summarize, a future perspective is offered.

  3. Semiconductor Nanocrystals as Light Harvesters in Solar Cells.

    Science.gov (United States)

    Etgar, Lioz

    2013-02-04

    Photovoltaic cells use semiconductors to convert sunlight into electrical current and are regarded as a key technology for a sustainable energy supply. Quantum dot-based solar cells have shown great potential as next generation, high performance, low-cost photovoltaics due to the outstanding optoelectronic properties of quantum dots and their multiple exciton generation (MEG) capability. This review focuses on QDs as light harvesters in solar cells, including different structures of QD-based solar cells, such as QD heterojunction solar cells, QD-Schottky solar cells, QD-sensitized solar cells and the recent development in organic-inorganic perovskite heterojunction solar cells. Mechanisms, procedures, advantages, disadvantages and the latest results obtained in the field are described. To summarize, a future perspective is offered.

  4. Semiconductor Nanocrystals as Light Harvesters in Solar Cells

    Science.gov (United States)

    Etgar, Lioz

    2013-01-01

    Photovoltaic cells use semiconductors to convert sunlight into electrical current and are regarded as a key technology for a sustainable energy supply. Quantum dot-based solar cells have shown great potential as next generation, high performance, low-cost photovoltaics due to the outstanding optoelectronic properties of quantum dots and their multiple exciton generation (MEG) capability. This review focuses on QDs as light harvesters in solar cells, including different structures of QD-based solar cells, such as QD heterojunction solar cells, QD-Schottky solar cells, QD-sensitized solar cells and the recent development in organic-inorganic perovskite heterojunction solar cells. Mechanisms, procedures, advantages, disadvantages and the latest results obtained in the field are described. To summarize, a future perspective is offered. PMID:28809318

  5. Rational Strategies for Efficient Perovskite Solar Cells.

    Science.gov (United States)

    Seo, Jangwon; Noh, Jun Hong; Seok, Sang Il

    2016-03-15

    A long-standing dream in the large scale application of solar energy conversion is the fabrication of solar cells with high-efficiency and long-term stability at low cost. The realization of such practical goals depends on the architecture, process and key materials because solar cells are typically constructed from multilayer heterostructures of light harvesters, with electron and hole transporting layers as a major component. Recently, inorganic-organic hybrid lead halide perovskites have attracted significant attention as light absorbers for the fabrication of low-cost and high-efficiency solar cells via a solution process. This mainly stems from long-range ambipolar charge transport properties, low exciton binding energies, and suitable band gap tuning by managing the chemical composition. In our pioneering work, a new photovoltaic platform for efficient perovskite solar cells (PSCs) was proposed, which yielded a high power conversion efficiency (PCE) of 12%. The platform consisted of a pillared architecture of a three-dimensional nanocomposite of perovskites fully infiltrating mesoporous TiO2, resulting in the formation of continuous phases and perovskite domains overlaid with a polymeric hole conductor. Since then, the PCE of our PSCs has been rapidly increased from 3% to over 20% certified efficiency. The unprecedented increase in the PCE can be attributed to the effective integration of the advantageous attributes of the refined bicontinuous architecture, deposition process, and composition of perovskite materials. Specifically, the bicontinuous architectures used in the high efficiency comprise a layer of perovskite sandwiched between mesoporous metal-oxide layer, which is a very thinner than that of used in conventional dye-sensitized solar cells, and hole-conducting contact materials with a metal back contact. The mesoporous scaffold can affect the hysteresis under different scan direction in measurements of PSCs. The hysteresis also greatly depends on

  6. METHOD AND APPARATUS FOR CHARACTERIZATION OF A SOLAR CELL

    DEFF Research Database (Denmark)

    2017-01-01

    ; and estimating variations in the solar cell, thereby electrically characterizing the solar cell. The disclosure further relates to a solar cell characterization apparatus for characterization of a solar cell, comprising: a light source for generating an optical probe light; a modulation unit, configured...... to produce modulated probe light by modulating the optical probe light with a modulation frequency of between 100 kHz and 0 MHz; a light scanning unit for scanning the modulated probe light such that said modulated probe light is incident on at least a part of the surface of the solar cell; and a 1 signal...

  7. Fabrication and Characterization of Dye-Sensitized Solar Cells

    OpenAIRE

    Mohamed FATHALLAH; Ahmed TORCHANI; Rached GHARBI

    2014-01-01

    Dye-sensitized solar cell (DSSC) constitutes a real revolution in the conversion of solar energy into electricity after 40 years of the invention of silicon solar cells. The working mechanism is based on a photoelectrochemical system, similar to the photosynthesis in plant leaves. The efficiencies of the DSSC are high as those obtained from amorphous silicon solar cells (10-11 %) and intensive efforts are done in different directions to improve this efficiency.

  8. Fabrication and Characterization of Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Mohamed FATHALLAH

    2014-05-01

    Full Text Available Dye-sensitized solar cell (DSSC constitutes a real revolution in the conversion of solar energy into electricity after 40 years of the invention of silicon solar cells. The working mechanism is based on a photoelectrochemical system, similar to the photosynthesis in plant leaves. The efficiencies of the DSSC are high as those obtained from amorphous silicon solar cells (10-11 % and intensive efforts are done in different directions to improve this efficiency.

  9. Highly efficient light management for perovskite solar cells.

    Science.gov (United States)

    Wang, Dong-Lin; Cui, Hui-Juan; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

    2016-01-06

    Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells.

  10. Recent progress in Si thin film technology for solar cells

    Science.gov (United States)

    Kuwano, Yukinori; Nakano, Shoichi; Tsuda, Shinya

    1991-11-01

    Progress in Si thin film technology 'specifically amorphous Si (a-Si) and polycrystalline Si (poly-Si) thin film' for solar cells is summarized here from fabrication method, material, and structural viewpoints. In addition to a-Si, primary results on poly-Si thin film research are discussed. Various applications for a-Si solar cells are mentioned, and consumer applications and a-Si solar cell photovoltaic systems are introduced. New product developments include see-through solar cells, solar cell roofing tiles, and ultra-light flexible solar cells. As for new systems, air conditioning equipment powered by solar cells is described. Looking to the future, the proposed GENESIS project is discussed.

  11. Perovskite Materials: Solar Cell and Optoelectronic Applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Bin [ORNL; Geohegan, David B [ORNL; Xiao, Kai [ORNL

    2017-01-01

    Hybrid organometallic trihalide perovskites are promising candidates in the applications for next-generation, high-performance, low-cost optoelectronic devices, including photovoltaics, light emitting diodes, and photodetectors. Particularly, the solar cells based on this type of materials have reached 22% lab scale power conversion efficiency in only about seven years, comparable to the other thin film photovoltaic technologies. Hybrid perovskite materials not only exhibit superior optoelectronic properties, but also show many interesting physical properties such as ion migration and defect physics, which may allow the exploration of more device functionalities. In this article, the fundamental understanding of the interrelationships between crystal structure, electronic structure, and material properties is discussed. Various chemical synthesis and processing methods for superior device performance in solar cells and optoelectronic devices are reviewed.

  12. Thin-film polycrystalline silicon solar cells

    Science.gov (United States)

    Funghnan, B. W.; Blanc, J.; Phillips, W.; Redfield, D.

    1980-08-01

    Thirty-four new solar cells were fabricated on Wacker Sislo substrates and the AM-1 parameters were measured. A detailed comparison was made between the measurement of minority carrier diffusion length by the OE method and the penetrating light laser scan grain boundary photoresponse linewidth method. The laser scan method has more experimental uncertainty and agrees within 10 to 50% with the QE method. It allows determination of L over a large area. Atomic hydrogen passivation studies continued on Wacker material by three techniques. A method of determining surface recombination velocity, s, from laser scan data was developed. No change in s in completed solar cells after H-plasma treatment was observed within experimental error. H-passivation of bare silicon cars as measured by the new laser scan photoconductivity technique showed very large effects.

  13. High efficiency thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Hans-Werner [Helmholtz Zentrum Berlin (Germany). Solar Energy

    2012-11-01

    Production of photovoltaics is growing worldwide on a gigawatt scale. Among the thin film technologies, Cu(In,Ga)S,Se{sub 2} (CIS or CIGS) based solar cells have been the focus of more and more attention. This paper aims to analyze the success of CIGS based solar cells and the potential of this technology for future photovoltaics large-scale production. Specific material properties make CIS unique and allow the preparation of the material with a wide range of processing options. The huge potential lies in the possibility to take advantage of modern thin film processing equipment and combine it with very high efficiencies beyond 20% already achieved on the laboratory scale. A sustainable development of this technology could be realized by modifying the materials and replacing indium by abundant elements. (orig.)

  14. A Bicontinuous Double Gyroid Hybrid Solar Cell

    KAUST Repository

    Crossland, Edward J. W.

    2009-08-12

    We report the first successful application of an ordered bicontinuous gyroid semiconducting network in a hybrid bulk heterojunction solar cell. The freestanding gyroid network is fabricated by electrochemical deposition into the 10 nm wide voided channels of a self-assembled, selectively degradable block copolymer film. The highly ordered pore structure is ideal for uniform infiltration of an organic hole transporting material, and solid-state dye-sensitized solar cells only 400 nm thick exhibit up to 1.7% power conversion efficiency. This patterning technique can be readily extended to other promising heterojunction systems and is a major step toward realizing the full potential of self-assembly in the next generation of device technologies. © 2009 American Chemical Society.

  15. Surface passivation for CdTe devices

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Matthew O.; Perkins, Craig L.; Burst, James M.; Gessert, Timothy A.; Barnes, Teresa M.; Metzger, Wyatt K.

    2017-08-01

    In one embodiment, a method for surface passivation for CdTe devices is provided. The method includes adjusting a stoichiometry of a surface of a CdTe material layer such that the surface becomes at least one of stoichiometric or Cd-rich; and reconstructing a crystalline lattice at the surface of the CdTe material layer by annealing the adjusted surface.

  16. Plasmonic Dye-Sensitized Solar Cells

    KAUST Repository

    Ding, I-Kang

    2010-12-14

    This image presents a scanning electron microscopy image of solid state dye-sensitized solar cell with a plasmonic back reflector, overlaid with simulated field intensity plots when monochromatic light is incident on the device. Plasmonic back reflectors, which consist of 2D arrays of silver nanodomes, can enhance absorption through excitation of plasmonic modes and increased light scattering, as reported by Michael D. McGehee, Yi Cui, and co-workers.

  17. Milestones Toward 50% Efficient Solar Cell Modules

    Science.gov (United States)

    2007-09-01

    efficiency, both at solar cells and module level. The optical system consists of a tiled nonimaging concentrating system, coupled with a spectral...which combines a nonimaging optical concentrator (which does not require tracking and is called a static concentrator) with spectral splitting...DESIGN AND RESULTS The optical design is based on non-symmetric, nonimaging optics, tiled into an array. The central issues in the optical system

  18. Nanostructured dye-sensitized solar cells

    OpenAIRE

    Palma, Giuseppina

    2014-01-01

    2012/2013 Dye-sensitized solar cells (DSSCs) represent a promising alternative to silicon-based technology. From the first publications about DSSCs in the 90s, they are considered an important breakthrough for achieving high efficiency by using relatively inexpensive and abundant materials. Stability and efficiency are two crucial points in the development of this new class of hybrid photovoltaic devices. Most of the DSSC studies carried out over the past twenty years are based on the o...

  19. Fiscal 1976 Sunshine Project result report. R and D on photovoltaic power generation system (R and D on 2-6 group compound semiconductor solar cells); 1976 nendo taiyoko hatsuden system no kenkyu kaihatsu seika hokokusho. 2-6 zoku kagobutsu handotai taiyo denchi no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1977-03-31

    This report describes the fiscal 1976 research result on 2-6 group compound semiconductor solar cells for photovoltaic power generation systems. The research aims at the system less than 1/100 in cost. Vapor deposition resulted in failure to obtain high-efficiency cells. Vapor-phase growth revealed Cd-Te single-crystal solar cell is promising, however, resulted in failure to obtain high-efficiency thin film elements. Both chemical deposition and sintering succeeded in mass production of prototype high-efficiency elements equal in performance. However, since chemically deposited CdS film is too thin having higher serial resistance, it requires In{sub 2}O{sub 3} auxiliary transmissive electrodes on glass substrates. Since CdTe film and CdS film also require completely different vapor deposition processes in hetero- junction, chemical deposition is more disadvantageous in cost than sintering. CdTe thin film fabricated by screen printing/sintering is most promising. Since Cd is harmful to human bodies, study was made on pollution preventive measures in its production or use stage, and accidents or fires, obtaining some results. (NEDO)

  20. Accelerated stress testing of terrestrial solar cells

    Science.gov (United States)

    Lathrop, J. W.; Hawkins, D. C.; Prince, J. L.; Walker, H. A.

    1982-01-01

    The development of an accelerated test schedule for terrestrial solar cells is described. This schedule, based on anticipated failure modes deduced from a consideration of IC failure mechanisms, involves bias-temperature testing, humidity testing (including both 85-85 and pressure cooker stress), and thermal-cycle thermal-shock testing. Results are described for 12 different unencapsulated cell types. Both gradual electrical degradation and sudden catastrophic mechanical change were observed. These effects can be used to discriminate between cell types and technologies relative to their reliability attributes. Consideration is given to identifying laboratory failure modes which might lead to severe degradation in the field through second quadrant operation. Test results indicate that the ability of most cell types to withstand accelerated stress testing depends more on the manufacturer's design, processing, and worksmanship than on the particular metallization system. Preliminary tests comparing accelerated test results on encapsulated and unencapsulated cells are described.

  1. PbSe Nanocrystal Excitonic Solar Cells

    KAUST Repository

    Choi, Joshua J.

    2009-11-11

    We report the design, fabrication, and characterization of colloidal PbSe nanocrystal (NC)-based photovoltaic test structures that exhibit an excitonic solar cell mechanism. Charge extraction from the NC active layer is driven by a photoinduced chemical potential energy gradient at the nanostructured heterojunction. By minimizing perturbation to PbSe NC energy levels and thereby gaining insight into the "intrinsic" photovoltaic properties and charge transfer mechanism of PbSe NC, we show a direct correlation between interfacial energy level offsets and photovoltaic device performance. Size dependent PbSe NC energy levels were determined by cyclic voltammetry and optical spectroscopy and correlated to photovoltaic measurements. Photovoltaic test structures were fabricated from PbSe NC films sandwiched between layers of ZnO nanoparticles and PEDOT:PSS as electron and hole transporting elements, respectively. The device current-voltage characteristics suggest a charge separation mechanism that Is distinct from previously reported Schottky devices and consistent with signatures of excitonic solar cells. Remarkably, despite the limitation of planar junction structure, and without film thickness optimization, the best performing device shows a 1-sun power conversion efficiency of 3.4%, ranking among the highest performing NC-based solar cells reported to date. © 2009 American Chemical Society.

  2. Crossed BiOI flake array solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Kewei; Jia, Falong; Zhang, Lizhi [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan (China); Zheng, Zhi [Institute of Surface Micro and Nano Materials, Xuchang University (China)

    2010-12-15

    We report a new kind of solar cell based on crossed flake-like BiOI arrays for the first time. The BiOI flake arrays were fabricated on an FTO glass with a TiO{sub 2} block layer at room temperature by successive ionic layer adsorption and reaction (SILAR) method. The resulting BiOI flake array solar cell exhibited enhanced photovoltaic performance under solar illumination. This work provides an attractive and new solar cell system and a facile route to fabricate low cost and non-toxic solar cell. (author)

  3. Novel patterning of CdS / CdTe thin film with back contacts for photovoltaic application

    Science.gov (United States)

    Ilango, Murugaiya Sridar; Ramasesha, Sheela K.

    2018-04-01

    The heterostructure of patterned CdS / CdTe thin films with back contact have been devised with electron beam lithography and fabricated using sputter deposition technique. The metallic contacts for n-CdS and p-CdTe are patterned such that both are placed at the bottom of the cell. This avoids losses due to contact shading and increases absorption in the window layer. Patterning of the device surface helps in increasing the junction area which can modulate the absorption of more number of photons due to total internal reflection. Computing the surface area between a planar and a patterned device has revealed 133% increase in the junction area. The physical and optical properties of the sputter-deposited CdS / CdTe layers are also presented. J- V characteristics of the solar cell showed the fill factor to be 25.9%, open circuit voltage to be 17 mV and short-circuit current density to be 113.68 A/m2. The increase in surface area is directly related to the increase in the short circuit current of the photovoltaic cell, which is observed from the results of simulated model in Atlas / Silvaco.

  4. Alloyed Aluminum Contacts for Silicon Solar Cells

    International Nuclear Information System (INIS)

    Tin Tin Aye

    2010-12-01

    Aluminium is usually deposited and alloyed at the back of p-p silicon solar cell for making a good ohmic contact and establishing a back electric field which avoids carrier recombination of the back surface. It was the deposition of aluminum on multicrystalline silicon (mc-Si) substrate at various annealing temperature. Physical and elemental analysis was carried out by using scanning electron microscopy (SEM) and X-rays diffraction (XRD). The electrical (I-V) characteristic of the photovoltaic cell was also measured.

  5. Recent Advances in High Efficiency Solar Cells

    Institute of Scientific and Technical Information of China (English)

    Yoshio; Ohshita; Hidetoshi; Suzuki; Kenichi; Nishimura; Masafumi; Yamaguchi

    2007-01-01

    1 Results The conversion efficiency of sunlight to electricity is limited around 25%,when we use single junction solar cells. In the single junction cells,the major energy losses arise from the spectrum mismatching. When the photons excite carriers with energy well in excess of the bandgap,these excess energies were converted to heat by the rapid thermalization. On the other hand,the light with lower energy than that of the bandgap cannot be absorbed by the semiconductor,resulting in the losses. One way...

  6. Solar energy powered microbial fuel cell with a reversible bioelectrode

    NARCIS (Netherlands)

    Strik, D.P.B.T.B.; Hamelers, H.V.M.; Buisman, C.J.N.

    2010-01-01

    The solar energy powered microbial fuel cell is an emerging technology for electricity generation via electrochemically active microorganisms fueled by solar energy via in situ photosynthesized metabolites from algae, cyanobacteria, or living higher plants. A general problem with microbial fuel

  7. Interactive Visual Analysis for Organic Photovoltaic Solar Cells

    KAUST Repository

    Abouelhassan, Amal A.

    2017-01-01

    Organic Photovoltaic (OPV) solar cells provide a promising alternative for harnessing solar energy. However, the efficient design of OPV materials that achieve better performance requires support by better-tailored visualization tools than

  8. Inverted amorphous silicon solar cell utilizing cermet layers

    Science.gov (United States)

    Hanak, Joseph J.

    1979-01-01

    An amorphous silicon solar cell incorporating a transparent high work function metal cermet incident to solar radiation and a thick film cermet contacting the amorphous silicon opposite to said incident surface.

  9. High Temperature InGaN-based Solar Cells

    Data.gov (United States)

    National Aeronautics and Space Administration — An efficient generation of solar power in a space environment is an enduring challenging for all NASA missions. The current available solar cells, however, suffer...

  10. Temperature dependence of organic solar cell parameters

    Energy Technology Data Exchange (ETDEWEB)

    Richter, Matthias; Mueller, Klaus; Philip, Shine; Paloumpa, Ioanna; Henkel, Karsten; Schmeisser, Dieter [Brandenburgische Technische Universitaet Cottbus (Germany). Angewandte Physik - Sensorik

    2009-07-01

    The influence of an annealing step on the parameters of bulk heterojunction organic solar cells is investigated. In order to fabricate the solar cells we use glass coated with ITO (indium-tin oxide) as a substrate on which the active layer consisting of P3HT and PCBM is spincoated. Al-electrodes are evaporated on top of the active layer. We use PEDOT:PSS as buffer layer. Each sample is annealed at different temperatures for a short time. Between every temperature step the I-V characteristic of the cell is measured. The following parameters are derived afterwards: FF, I{sub sc} (density), V{sub oc}. Also the efficiency is estimated. The results show a maximum cell efficiency for drying at 100 C for 20sec. A further important step for preparation is the drying procedure of the PEDOT:PSS layer. Here an improvement of about 50% in cell efficiency is measured after drying at 50 C for 5 days under inert gas atmosphere.

  11. Research on fabrication technology for thin film solar cells for practical use. Survey on the commercialization analysis; Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Jitsuyoka kaiseki ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the survey results on the technological trend, safety and latest technologies of thin film solar cells in fiscal 1994. As the fabrication technology for amorphous film solar cells, three-electrode plasma CVD was surveyed as fabrication method for high-mobility materials, and hydrogen radical CVD as fabrication method for high-photostable films. Current foreign and domestic reliability tests were surveyed for reliability evaluation of solar cells. In order to ascertain the performance, efficiency, physical properties and optimum structure of polycrystalline Si thin film solar cells, previously reported test results on physical properties such as carrier concentration, carrier lifetime and mobility of films were surveyed together with device simulation results. In addition, technologies for high-efficiency CuInSe2 system and CdTe system solar cells, technologies for cost reduction and mass production, and environmental influence were surveyed. Estimation of production costs for cell modules, and safety of thin film solar cells were also surveyed.

  12. Materials That Enhance Efficiency and Radiation Resistance of Solar Cells

    Science.gov (United States)

    Sun, Xiadong; Wang, Haorong

    2012-01-01

    A thin layer (approximately 10 microns) of a novel "transparent" fluorescent material is applied to existing solar cells or modules to effectively block and convert UV light, or other lower solar response waveband of solar radiation, to visible or IR light that can be more efficiently used by solar cells for additional photocurrent. Meanwhile, the layer of fluorescent coating material remains fully "transparent" to the visible and IR waveband of solar radiation, resulting in a net gain of solar cell efficiency. This innovation alters the effective solar spectral power distribution to which an existing cell gets exposed, and matches the maximum photovoltaic (PV) response of existing cells. By shifting a low PV response waveband (e.g., UV) of solar radiation to a high PV response waveband (e.g. Vis-Near IR) with novel fluorescent materials that are transparent to other solar-cell sensitive wavebands, electrical output from solar cells will be enhanced. This approach enhances the efficiency of solar cells by converting UV and high-energy particles in space that would otherwise be wasted to visible/IR light. This innovation is a generic technique that can be readily implemented to significantly increase efficiencies of both space and terrestrial solar cells, without incurring much cost, thus bringing a broad base of economical, social, and environmental benefits. The key to this approach is that the "fluorescent" material must be very efficient, and cannot block or attenuate the "desirable" and unconverted" waveband of solar radiation (e.g. Vis-NIR) from reaching the cells. Some nano-phosphors and novel organometallic complex materials have been identified that enhance the energy efficiency on some state-of-the-art commercial silicon and thin-film-based solar cells by over 6%.

  13. Enhancing Solar Cell Efficiency Using Photon Upconversion Materials.

    Science.gov (United States)

    Shang, Yunfei; Hao, Shuwei; Yang, Chunhui; Chen, Guanying

    2015-10-27

    Photovoltaic cells are able to convert sunlight into electricity, providing enough of the most abundant and cleanest energy to cover our energy needs. However, the efficiency of current photovoltaics is significantly impeded by the transmission loss of sub-band-gap photons. Photon upconversion is a promising route to circumvent this problem by converting these transmitted sub-band-gap photons into above-band-gap light, where solar cells typically have high quantum efficiency. Here, we summarize recent progress on varying types of efficient upconversion materials as well as their outstanding uses in a series of solar cells, including silicon solar cells (crystalline and amorphous), gallium arsenide (GaAs) solar cells, dye-sensitized solar cells, and other types of solar cells. The challenge and prospect of upconversion materials for photovoltaic applications are also discussed.

  14. Enhancing Solar Cell Efficiency Using Photon Upconversion Materials

    Directory of Open Access Journals (Sweden)

    Yunfei Shang

    2015-10-01

    Full Text Available Photovoltaic cells are able to convert sunlight into electricity, providing enough of the most abundant and cleanest energy to cover our energy needs. However, the efficiency of current photovoltaics is significantly impeded by the transmission loss of sub-band-gap photons. Photon upconversion is a promising route to circumvent this problem by converting these transmitted sub-band-gap photons into above-band-gap light, where solar cells typically have high quantum efficiency. Here, we summarize recent progress on varying types of efficient upconversion materials as well as their outstanding uses in a series of solar cells, including silicon solar cells (crystalline and amorphous, gallium arsenide (GaAs solar cells, dye-sensitized solar cells, and other types of solar cells. The challenge and prospect of upconversion materials for photovoltaic applications are also discussed

  15. Si Wire-Array Solar Cells

    Science.gov (United States)

    Boettcher, Shannon

    2010-03-01

    Micron-scale Si wire arrays are three-dimensional photovoltaic absorbers that enable orthogonalization of light absorption and carrier collection and hence allow for the utilization of relatively impure Si in efficient solar cell designs. The wire arrays are grown by a vapor-liquid-solid-catalyzed process on a crystalline (111) Si wafer lithographically patterned with an array of metal catalyst particles. Following growth, such arrays can be embedded in polymethyldisiloxane (PDMS) and then peeled from the template growth substrate. The result is an unusual photovoltaic material: a flexible, bendable, wafer-thickness crystalline Si absorber. In this paper I will describe: 1. the growth of high-quality Si wires with controllable doping and the evaluation of their photovoltaic energy-conversion performance using a test electrolyte that forms a rectifying conformal semiconductor-liquid contact 2. the observation of enhanced absorption in wire arrays exceeding the conventional light trapping limits for planar Si cells of equivalent material thickness and 3. single-wire and large-area solid-state Si wire-array solar cell results obtained to date with directions for future cell designs based on optical and device physics. In collaboration with Michael Kelzenberg, Morgan Putnam, Joshua Spurgeon, Daniel Turner-Evans, Emily Warren, Nathan Lewis, and Harry Atwater, California Institute of Technology.

  16. Applications of Laser Precisely Processing Technology in Solar Cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    According to the design method of laser resonator cavity, we optimized the primary parameters of resonator and utilized LD arrays symmetrically pumping manner to implementing output of the high-brightness laser in our laser cutter, then which was applied to precisely cutting the conductive film of CuInSe2 solar cells, the buried contact silicon solar cells' electrode groove, and perforating in wafer which is used to the emitter wrap through silicon solar cells. Laser processing precision was less than 40μm, the results have met solar cell's fabrication technology, and made finally the buried cells' conversion efficiency be improved from 18% to 21% .

  17. Photovoltaic characteristics of porous silicon /(n+ - p) silicon solar cells

    International Nuclear Information System (INIS)

    Dzhafarov, T.D.; Aslanov, S.S.; Ragimov, S.H.; Sadigov, M.S.; Nabiyeva, A.F.; Yuksel, Aydin S.

    2012-01-01

    Full text : The purpose of this work is to improve the photovoltaic parameters of the screen-printed silicon solar cells by formation the nano-porous silicon film on the frontal surface of the cell. The photovoltaic characteristics of two type silicon solar cells with and without porous silicon layer were measured and compared. A remarkable increment of short-circuit current density and the efficiency by 48 percent and 20 percent, respectively, have been achieved for PS/(n + - pSi) solar cell comparing to (n + - p)Si solar cell without PS layer

  18. Industrialization of polymer solar cells - phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Lauritzen, H.; Krebs, F.C. [Technical Univ. of Denmark. DTU Energy Conversion, DTU Risoe Campus, Roskilde (Denmark); Andersen, Rasmus B. [Mekoprint A/S, Stoevrimg (Denmark); Bork, J.; Bentzen, B.

    2012-03-15

    A three-phased project with the objective to industrialize DTU's basic polymer solar cell technology was started in the summer of 2009. The technology comprises a specific design of the polymer solar cell and a corresponding roll-to-roll manufacturing process. This basic technology is referred to as ProcessOne in the open literature. The present report relates to the project's phase 1.The key tasks in phase 1 are to stream-line DTU's tech-nology for the industrial utilization, to demonstrate production according to this stream-lined technology at Mekoprint A/S and finally to fertilize the market for polymer solar cells by demonstrating their use in appli-cations that harmonize with their present maturity level. The main focus in the stream-lining of DTU's technology has been to demonstrate a convincing rate of reduction for the production cost, and thereby make a competitive price plausible. This has been materialized as a learning curve showing that the polymer technology presently develops considerably faster than the silicon technology. The polymer solar cells will, under the assumption that both technologies follow a projection of the learning curve, gain a cost-leading position within a reasonable time. A production cost of 5 Euro/Wp has already been demonstrated in DTU's pilot plant, and a road map for the further decrease to 1 Euro/Wp is drawn. This target is expected to be reached in 2013 in the ongoing phase 2 of the project. Another activity essential for the industrialization has been the launch of specialized materials, equipment and services required for the processing of DTU's polymer solar cells. Relevant products and services are made available for sale on DTU's homepage, www.energyconversion.dtu.dk. A production line for polymer solar cells has been established at Mekoprint. For this a retrofit solution was chosen where the core of an existing screen-printing line was dismantled and fitted to a slot-die printing head manufactured in DTU's workshop

  19. Preface to the SPECIAL ISSUE: Excitonic Solar Cells(II)

    Institute of Scientific and Technical Information of China (English)

    Jianjun Tian; Meicheng Li; Kaibo Zheng

    2016-01-01

    Among all the excitonic solar cells(ESCs)including dyesensitized solar cells(DSSCs),quantum solar cells(QDSCs),perovskites solar cells(PSCs),and organic photovoltaics(OPVs),PSCs attracted enormous research attention in the past 7 years and attained the highest power conversion efficiency(PCE)of over 20%with the biggest progress,from 3.8%to over 22.1%in 7 years.However,one can easily realize the fact that such a rapid progress achieved in PSCs was made possible is largely based on the fundamental knowledge,experimental skills,and characterization facilities obtained and accumulated through the multi-decade long endeavor in the study of other excitonic solar cells.Even though PSCs have attractedmuch research human resource and funding,the study on other excitonic solar cells has never stopped,and such persistent efforts

  20. Applications of Fluorogens with Rotor Structures in Solar Cells.

    Science.gov (United States)

    Ong, Kok-Haw; Liu, Bin

    2017-05-29

    Solar cells are devices that convert light energy into electricity. To drive greater adoption of solar cell technologies, higher cell efficiencies and reductions in manufacturing cost are necessary. Fluorogens containing rotor structures may be helpful in addressing some of these challenges due to their unique twisted structures and photophysics. In this review, we discuss the applications of rotor-containing molecules as dyes for luminescent down-shifting layers and luminescent solar concentrators, where their aggregation-induced emission properties and large Stokes shifts are highly desirable. We also discuss the applications of molecules containing rotors in third-generation solar cell technologies, namely dye-sensitized solar cells and organic photovoltaics, where the twisted 3-dimensional rotor structures are used primarily for aggregation control. Finally, we discuss perspectives on the future role of molecules containing rotor structures in solar cell technologies.

  1. Solare Cell Roof Tile And Method Of Forming Same

    Science.gov (United States)

    Hanoka, Jack I.; Real, Markus

    1999-11-16

    A solar cell roof tile includes a front support layer, a transparent encapsulant layer, a plurality of interconnected solar cells and a backskin layer. The front support layer is formed of light transmitting material and has first and second surfaces. The transparent encapsulant layer is disposed adjacent the second surface of the front support layer. The interconnected solar cells has a first surface disposed adjacent the transparent encapsulant layer. The backskin layer has a first surface disposed adjacent a second surface of the interconnected solar cells, wherein a portion of the backskin layer wraps around and contacts the first surface of the front support layer to form the border region. A portion of the border region has an extended width. The solar cell roof tile may have stand-offs disposed on the extended width border region for providing vertical spacing with respect to an adjacent solar cell roof tile.

  2. Progress in batteries and solar cells. Volume 5

    International Nuclear Information System (INIS)

    Shimotake, H.

    1984-01-01

    The 89 articles in this book are on research in batteries, solar cells and fuel cells. Topics include uses of batteries in electric powered vehicles, load management in power plants, batteries for miniature electronic devices, electrochemical processes, and various electrode and electrolyte materials, including organic compounds. Types of batteries discussed are lithium, lead-acid, manganese dioxide, Silver cells, Air cells, Nickel cells and solar cells. Problems of recharging and life cycle are also discussed

  3. Hybrid Solar Cells: Materials, Interfaces, and Devices

    Science.gov (United States)

    Mariani, Giacomo; Wang, Yue; Kaner, Richard B.; Huffaker, Diana L.

    Photovoltaic technologies could play a pivotal role in tackling future fossil fuel energy shortages, while significantly reducing our carbon dioxide footprint. Crystalline silicon is pervasively used in single junction solar cells, taking up 80 % of the photovoltaic market. Semiconductor-based inorganic solar cells deliver relatively high conversion efficiencies at the price of high material and manufacturing costs. A great amount of research has been conducted to develop low-cost photovoltaic solutions by incorporating organic materials. Organic semiconductors are conjugated hydrocarbon-based materials that are advantageous because of their low material and processing costs and a nearly unlimited supply. Their mechanical flexibility and tunable electronic properties are among other attractions that their inorganic counterparts lack. Recently, collaborations in nanotechnology research have combined inorganic with organic semiconductors in a "hybrid" effort to provide high conversion efficiencies at low cost. Successful integration of these two classes of materials requires a profound understanding of the material properties and an exquisite control of the morphology, surface properties, ligands, and passivation techniques to ensure an optimal charge carrier generation across the hybrid device. In this chapter, we provide background information of this novel, emerging field, detailing the various approaches for obtaining inorganic nanostructures and organic polymers, introducing a multitude of methods for combining the two components to achieve the desired morphologies, and emphasizing the importance of surface manipulation. We highlight several studies that have fueled new directions for hybrid solar cell research, including approaches for maximizing efficiencies by controlling the morphologies of the inorganic component, and in situ molecular engineering via electrochemical polymerization of a polymer directly onto the inorganic nanowire surfaces. In the end, we

  4. Self-Catalyzed CdTe Wires

    Directory of Open Access Journals (Sweden)

    Tom Baines

    2018-04-01

    Full Text Available CdTe wires have been fabricated via a catalyst free method using the industrially scalable physical vapor deposition technique close space sublimation. Wire growth was shown to be highly dependent on surface roughness and deposition pressure, with only low roughness surfaces being capable of producing wires. Growth of wires is highly (111 oriented and is inferred to occur via a vapor-solid-solid growth mechanism, wherein a CdTe seed particle acts to template the growth. Such seed particles are visible as wire caps and have been characterized via energy dispersive X-ray analysis to establish they are single phase CdTe, hence validating the self-catalysation route. Cathodoluminescence analysis demonstrates that CdTe wires exhibited a much lower level of recombination when compared to a planar CdTe film, which is highly beneficial for semiconductor applications.

  5. High p-Type Doping, Mobility, and Photocarrier Lifetime in Arsenic-Doped CdTe Single Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kuciauskas, Darius [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nagaoka, Akira [Kyoto University; University of Utah; McCoy, Jedidiah [Washington State University; Scarpulla, Michael A. [University of Utah

    2018-05-08

    Group-V element doping is promising for simultaneously maximizing the hole concentration and minority carrier lifetime in CdTe for thin film solar cells, but there are roadblocks concerning point defects including the possibility of self-compensation by AX metastability. Herein, we report on doping, lifetime, and mobility of CdTe single crystals doped with As between 10^16 and 10^20 cm-3 grown from the Cd solvent by the travelling heater method. Evidence consistent with AX instability as a major contributor to compensation in samples doped below 10^17 cm-3 is presented, while for higher-doped samples, precipitation of a second phase on planar structural defects is also observed and may explain spatial variation in properties such as lifetime. Rapid cooling after crystal growth increases doping efficiency and mobility for times up to 20-30 days at room temperature with the highest efficiencies observed close to 45% and a hole mobility of 70 cm2/Vs at room temperature. A doping limit in the low 10^17/cm3 range is observed for samples quenched at 200-300 degrees C/h. Bulk minority carrier lifetimes exceeding 20 ns are observed for samples doped near 10^16 cm-3 relaxed in the dark and for unintentionally doped samples, while a lifetime of nearly 5 ns is observed for 10^18 cm-3 As doping. These results help us to establish limits on properties expected for group-V doped CdTe polycrystalline thin films for use in photovoltaics.

  6. Monocrystalline silicon solar cells applied in photovoltaic system

    OpenAIRE

    L.A. Dobrzański; A. Drygała; M. Giedroć; M. Macek

    2012-01-01

    Purpose: The aim of the paper is to fabricate the monocrystalline silicon solar cells using the conventional technology by means of screen printing process and to make of them photovoltaic system.Design/methodology/approach: The investigation of current – voltage characteristic to determinate basic electrical properties of monocrystalline silicon solar cells were investigated under Standard Test Condition. Photovoltaic module was produced from solar cells with the largest short-circuit curren...

  7. Triple junction polymer solar cells for photoelectrochemical water splitting

    NARCIS (Netherlands)

    Esiner, S.; Eersel, van H.; Wienk, M.M.; Janssen, R.A.J.

    2013-01-01

    A triple junction polymer solar cell in a novel 1 + 2 type configuration provides photoelectrochemical water splitting in its maximum power point at V ˜ 1.70 V with an estimated solar to hydrogen energy conversion efficiency of 3.1%. The triple junction cell consists of a wide bandgap front cell and

  8. Performance improvement of silicon solar cells by nanoporous silicon coating

    Directory of Open Access Journals (Sweden)

    Dzhafarov T. D.

    2012-04-01

    Full Text Available In the present paper the method is shown to improve the photovoltaic parameters of screen-printed silicon solar cells by nanoporous silicon film formation on the frontal surface of the cell using the electrochemical etching. The possible mechanisms responsible for observed improvement of silicon solar cell performance are discussed.

  9. Intermediate Bandgap Solar Cells From Nanostructured Silicon

    Energy Technology Data Exchange (ETDEWEB)

    Black, Marcie [Bandgap Engineering, Lincoln, MA (United States)

    2014-10-30

    This project aimed to demonstrate increased electronic coupling in silicon nanostructures relative to bulk silicon for the purpose of making high efficiency intermediate bandgap solar cells using silicon. To this end, we formed nanowires with controlled crystallographic orientation, small diameter, <111> sidewall faceting, and passivated surfaces to modify the electronic band structure in silicon by breaking down the symmetry of the crystal lattice. We grew and tested these silicon nanowires with <110>-growth axes, which is an orientation that should produce the coupling enhancement.

  10. Optimal Speed Scaling with a Solar Cell

    OpenAIRE

    Barcelo, Neal; Kling, Peter; Nugent, Michael; Pruhs, Kirk

    2016-01-01

    We consider the setting of a sensor that consists of a speed-scalable processor, a battery, and a solar cell that harvests energy from its environment at a time-invariant recharge rate. The processor must process a collection of jobs of various sizes. Jobs arrive at different times and have different deadlines. The objective is to minimize the *recharge rate*, which is the rate at which the device has to harvest energy in order to feasibly schedule all jobs. The main result is a polynomial-ti...

  11. Transmutation doping of silicon solar cells

    Science.gov (United States)

    Wood, R. F.; Westbrook, R. D.; Young, R. T.; Cleland, J. W.

    1977-01-01

    Normal isotopic silicon contains 3.05% of Si-30 which transmutes to P-31 after thermal neutron absorption, with a half-life of 2.6 hours. This reaction is used to introduce extremely uniform concentrations of phosphorus into silicon, thus eliminating the areal and spatial inhomogeneities characteristic of chemical doping. Annealing of the lattice damage in the irradiated silicon does not alter the uniformity of dopant distribution. Transmutation doping also makes it possible to introduce phosphorus into polycrystalline silicon without segregation of the dopant at the grain boundaries. The use of neutron transmutation doped (NTD) silicon in solar cell research and development is discussed.

  12. Flexible ITO-Free Polymer Solar Cells

    DEFF Research Database (Denmark)

    Angmo, Dechan; Krebs, Frederik C

    2013-01-01

    Indium tin oxide (ITO) is the material-of-choice for transparent conductors in any optoelectronic application. However, scarce resources of indium and high market demand of ITO have created large price fluctuations and future supply concerns. In polymer solar cells (PSCs), ITO is the single......-cost alternatives to ITO suitable for use in PSCs. These alternatives belong to four material groups: polymers; metal and polymer composites; metal nanowires and ultra-thin metal films; and carbon nanotubes and graphene. We further present the progress of employing these alternatives in PSCs and identify future...

  13. Hydrogen passivation of silicon sheet solar cells

    International Nuclear Information System (INIS)

    Tsuo, Y.S.; Milstein, J.B.

    1984-01-01

    Significant improvements in the efficiencies of dendritic web and edge-supported-pulling silicon sheet solar cells have been obtained after hydrogen ion beam passivation for a period of ten minutes or less. We have studied the effects of the hydrogen ion beam treatment with respect to silicon material damage, silicon sputter rate, introduction of impurities, and changes in reflectance. The silicon sputter rate for constant ion beam flux of 0.60 +- 0.05 mA/cm 2 exhibits a maximum at approximately 1400-eV ion beam energy

  14. Solar Energy Materials & Solar Cells Solvent additives for tuning the photovoltaic properties of polymer – fullerene solar cells

    NARCIS (Netherlands)

    Sio, Antonietta De; Madena, Thomas; Huber, Ralph; Deschler, Felix; Como, Enrico Da; Esposito, Salvatore; Hauff, Elizabeth Von

    2011-01-01

    We use solvent additives as a simple method to tune the photovoltaic performance of poly-3-hexylthiophene (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) bulk heterojuncton solar cells. 1,2-dichlorobenzene (oDCB) was used as the reference solvent; chlorobenzene (CB) and 1,2,3,4-

  15. Ion-damage-free planarization or shallow angle sectioning of solar cells for mapping grain orientation and nanoscale photovoltaic properties

    Science.gov (United States)

    Kutes, Yasemin; Luria, Justin; Sun, Yu; Moore, Andrew; Aguirre, Brandon A.; Cruz-Campa, Jose L.; Aindow, Mark; Zubia, David; Huey, Bryan D.

    2017-05-01

    Ion beam milling is the most common modern method for preparing specific features for microscopic analysis, even though concomitant ion implantation and amorphization remain persistent challenges, particularly as they often modify materials properties of interest. Atomic force microscopy (AFM), on the other hand, can mechanically mill specific nanoscale regions in plan-view without chemical or high energy ion damage, due to its resolution, directionality, and fine load control. As an example, AFM-nanomilling (AFM-NM) is implemented for top-down planarization of polycrystalline CdTe thin film solar cells, with a resulting decrease in the root mean square (RMS) roughness by an order of magnitude, even better than for a low incidence FIB polished surface. Subsequent AFM-based property maps reveal a substantially stronger contrast, in this case of the short-circuit current or open circuit voltage during light exposure. Electron back scattering diffraction (EBSD) imaging also becomes possible upon AFM-NM, enabling direct correlations between the local materials properties and the polycrystalline microstructure. Smooth shallow-angle cross-sections are demonstrated as well, based on targeted oblique milling. As expected, this reveals a gradual decrease in the average short-circuit current and maximum power as the underlying CdS and electrode layers are approached, but a relatively consistent open-circuit voltage through the diminishing thickness of the CdTe absorber. AFM-based nanomilling is therefore a powerful tool for material characterization, uniquely providing ion-damage free, selective area, planar smoothing or low-angle sectioning of specimens while preserving their functionality. This enables novel, co-located advanced AFM measurements, EBSD analysis, and investigations by related techniques that are otherwise hindered by surface morphology or surface damage.

  16. Testing of gallium arsenide solar cells on the CRRES vehicle

    International Nuclear Information System (INIS)

    Trumble, T.M.

    1985-01-01

    A flight experiment was designed to determine the optimum design for gallium arsenide (GaAs) solar cell panels in a radiation environment. Elements of the experiment design include, different coverglass material and thicknesses, welded and soldered interconnects, different solar cell efficiencies, different solar cell types, and measurement of annealing properties. This experiment is scheduled to fly on the Combined Release and Radiation Effects Satellite (CRRES). This satellite will simultaneously measure the radiation environment and provide engineering data on solar cell degradation that can be directly related to radiation damage

  17. Flexible PCPDTBT:PCBM solar cells with integrated grating structures

    DEFF Research Database (Denmark)

    Oliveira Hansen, Roana Melina de; Liu, Yinghui; Madsen, Morten

    2013-01-01

    We report on development of flexible PCPDTBT:PCBM solar cells with integrated diffraction gratings on the bottom electrodes. The presented results address PCPDTBT:PCBM solar cells in an inverted geometry, which contains implemented grating structures whose pitch is tuned to match the absorption...... spectra of the active layer. This optimized solar cell structure leads to an enhanced absorption in the active layer and thus improved short-circuit currents and power conversion efficiencies in the fabricated devices. Fabrication of the solar cells on thin polyimide substrates which are compatible...

  18. Nanostructured InGaP Solar Cells, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The operating conditions of conventional multijunction solar cells are severely limited by the current matching requirements of serially connected devices. The goal...

  19. Enhanced Photovoltaic Properties of Gradient Doping Solar Cells

    International Nuclear Information System (INIS)

    Zhang Chun-Lei; Du Hui-Jing; Zhu Jian-Zhuo; Xu Tian-Fu; Fang Xiao-Yong

    2012-01-01

    An optimum design of a-Si:H(n)/a-Si:H(i)/c-Si(p) heterojunction solar cell is realized with 24.27% conversion efficiency by gradient doping of the a-Si:H(n) layer. The photovoltaic properties are simulated by the AFORSHET software. Besides the additional electric field caused by the gradient doping, the enhanced and widen spectral response also improves the solar cell performance compared with the uniform-doping mode. The simulation shows that the gradient doping is efficient to improve the photovoltaic performance of the solar cells. The study is valuable for the solar cell design with excellent performances

  20. Enhanced photovoltaic performance of an inclined nanowire array solar cell.

    Science.gov (United States)

    Wu, Yao; Yan, Xin; Zhang, Xia; Ren, Xiaomin

    2015-11-30

    An innovative solar cell based on inclined p-i-n nanowire array is designed and analyzed. The results show that the inclined geometry can sufficiently increase the conversion efficiency of solar cells by enhancing the absorption of light in the active region. By tuning the nanowire array density, nanowire diameter, nanowire length, as well as the proportion of intrinsic region of the inclined nanowire solar cell, a remarkable efficiency in excess of 16% can be obtained in GaAs. Similar results have been obtained in InP and Si nanowire solar cells, demonstrating the universality of the performance enhancement of inclined nanowire arrays.

  1. Investigation of back surface fields effect on bifacial solar cells

    Science.gov (United States)

    Sepeai, Suhaila; Sulaiman, M. Y.; Sopian, Kamaruzzaman; Zaidi, Saleem H.

    2012-11-01

    A bifacial solar cell, in contrast with a conventional monofacial solar cell, produces photo-generated current from both front and back sides. Bifacial solar cell is an attractive candidate for enhancing photovoltaic (PV) market competitiveness as well as supporting the current efforts to increase efficiency and lower material costs. This paper reports on the fabrication of bifacial solar cells using phosphorus-oxytrichloride (POCl3) emitter formation on p-type, nanotextured silicon (Si) wafer. Backside surface field was formed through Al-diffusion using conventional screen-printing process. Bifacial solar cells with a structure of n+pp+ with and without back surface field (BSF) were fabricated in which silicon nitride (SiN) anti reflection and passivation films were coated on both sides, followed by screen printing of Argentum (Ag) and Argentum/Aluminum (Ag/Al) on front and back contacts, respectively. Bifacial solar cells without BSF exhibited open circuit voltage (VOC) of 535 mV for front and 480 mV for back surface. With Al-alloyed BSF bifacial solar cells, the VOC improved to 580 mV for the front surface and 560 mV for the back surface. Simulation of bifacial solar cells using PC1D and AFORS software demonstrated good agreement with experimental results. Simulations showed that best bifacial solar cells are achieved through a combination of high lifetime wafer, low recombination back surface field, reduced contact resistance, and superior surface passivation.

  2. Organic solar cells theory, experiment, and device simulation

    CERN Document Server

    Tress, Wolfgang

    2014-01-01

    This book covers in a textbook-like fashion the basics or organic solar cells, addressing the limits of photovoltaic energy conversion and giving a well-illustrated introduction to molecular electronics with focus on the working principle and characterization of organic solar cells. Further chapters based on the author's dissertation focus on the electrical processes in organic solar cells by presenting a detailed drift-diffusion approach to describe exciton separation and charge-carrier transport and extraction. The results, although elaborated on small-molecule solar cells and with focus on

  3. Recyclable organic solar cells on cellulose nanocrystal substrates.

    Science.gov (United States)

    Zhou, Yinhua; Fuentes-Hernandez, Canek; Khan, Talha M; Liu, Jen-Chieh; Hsu, James; Shim, Jae Won; Dindar, Amir; Youngblood, Jeffrey P; Moon, Robert J; Kippelen, Bernard

    2013-01-01

    Solar energy is potentially the largest source of renewable energy at our disposal, but significant advances are required to make photovoltaic technologies economically viable and, from a life-cycle perspective, environmentally friendly, and consequently scalable. Cellulose nanomaterials are emerging high-value nanoparticles extracted from plants that are abundant, renewable, and sustainable. Here, we report on the first demonstration of efficient polymer solar cells fabricated on optically transparent cellulose nanocrystal (CNC) substrates. The solar cells fabricated on the CNC substrates display good rectification in the dark and reach a power conversion efficiency of 2.7%. In addition, we demonstrate that these solar cells can be easily separated and recycled into their major components using low-energy processes at room temperature, opening the door for a truly recyclable solar cell technology. Efficient and easily recyclable organic solar cells on CNC substrates are expected to be an attractive technology for sustainable, scalable, and environmentally-friendly energy production.

  4. Photosensitizers from Spirulina for Solar Cell

    Directory of Open Access Journals (Sweden)

    Liqiu Wang

    2014-01-01

    Full Text Available Spirulina is a kind of blue-green algae with good photosynthetic efficiency and might be used for photovoltaic power generation. So this paper used living spirulina as novel photosensitizer to construct spirulina biosolar cell. The results showed that spirulina had the photoelectric conversion effect, and could let the spirulina biosolar cell have 70 μA photocurrent. Meanwhile, adding glucose sucrose or chitosan in the spirulina anode chamber, they could make the maxima current density of the cell greatly increased by 80 μA, 100 μA, and 84 μA, respectively, and the sucrose could improve the maximum power density of the cell to 63 mW/m−2. Phycobiliprotein played an important role in the photosynthesis of spirulina. So in this paper phycobiliprotein was extracted from spirulina to composite with squaraine dye to sensitize nanocrystalline TiO2 photoanode for building dye sensitized solar cell, and the photoelectric properties of the cell also were investigated.

  5. Solar Cell Capacitance Determination Based on an RLC Resonant Circuit

    Directory of Open Access Journals (Sweden)

    Petru Adrian Cotfas

    2018-03-01

    Full Text Available The capacitance is one of the key dynamic parameters of solar cells, which can provide essential information regarding the quality and health state of the cell. However, the measurement of this parameter is not a trivial task, as it typically requires high accuracy instruments using, e.g., electrical impedance spectroscopy (IS. This paper introduces a simple and effective method to determine the electric capacitance of the solar cells. An RLC (Resistor Inductance Capacitor circuit is formed by using an inductor as a load for the solar cell. The capacitance of the solar cell is found by measuring the frequency of the damped oscillation that occurs at the moment of connecting the inductor to the solar cell. The study is performed through simulation based on National Instruments (NI Multisim application as SPICE simulation software and through experimental capacitance measurements of a monocrystalline silicon commercial solar cell and a photovoltaic panel using the proposed method. The results were validated using impedance spectroscopy. The differences between the capacitance values obtained by the two methods are of 1% for the solar cells and of 9.6% for the PV panel. The irradiance level effect upon the solar cell capacitance was studied obtaining an increase in the capacitance in function of the irradiance. By connecting different inductors to the solar cell, the frequency effect upon the solar cell capacitance was studied noticing a very small decrease in the capacitance with the frequency. Additionally, the temperature effect over the solar cell capacitance was studied achieving an increase in capacitance with temperature.

  6. Red-shift of the photoluminescent emission peaks of CdTe quantum dots due to the synergistic interaction with carbon quantum dot mixtures

    International Nuclear Information System (INIS)

    Pelayo, E; Zazueta, A; López-Delgado, R; Ayón, A; Saucedo, E; Ruelas, R

    2016-01-01

    We report the relatively large red-shift effect observed in down-shifting carbon quantum dots (CQDs) that is anticipated to have a positive impact on the power conversion efficiency of solar cells. Specifically, with an excitation wavelength of 390 nm, CQDs of different sizes, exhibited down-shifted emission peaks centered around 425 nm. However, a solution comprised of a mixture of CQDs of different sizes, was observed to have an emission peak red-shifted to 515 nm. The effect could arise when larger carbon quantum dots capture the photons emitted by their smaller counterparts followed by the subsequent re-emission at longer wavelengths. Furthermore, the red-shift effect was also observed in CdTe QDs when added to a solution with the aforementioned mixture of Carbon QDs. Thus, whereas a solution solely comprised of a collection of CdTe QDs of different sizes, exhibited a down-shifted photoluminescence centered around 555 nm, the peak was observed to be further red-shifted to 580 nm when combined with the solution of CQDs of different sizes. The quantum dot characterization included crystal structure analysis as well as photon absorption and photoluminescence wavelengths. Subsequently, the synthesized QDs were dispersed in a polymeric layer of poly-methyl-methacrylate (PMMA) and incorporated on functional and previously characterized solar cells, to quantify their influence in the electrical performance of the photovoltaic structures. We discuss the synthesis and characterization of the produced Carbon and CdTe QDs, as well as the observed improvement in the power conversion efficiency of the fabricated photovoltaic devices. (paper)

  7. Chalcopyrite semiconductors for quantum well solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Afshar, Maziar; Sadewasser, Sascha; Albert, Juergen; Lehmann, Sebastian; Abou-Ras, Daniel; Lux-Steiner, Martha C. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Marron, David Fuertes [Instituto de Energia Solar - ETSIT, Universidad Politecnica de Madrid, Ciudad Universitaria s.n., 28040 Madrid (Spain); Rockett, Angus A. [Department of Materials Science and Engineering, University of Illinois, 1304 W. Green Street, Urbana, IL 61801 (United States); Raesaenen, Esa [Nanoscience Center, Department of Physics University of Jyvaeskylae, FI-40014 Jyvaeskylae (Finland)

    2011-11-15

    The possibilities of using highly absorbing chalcopyrite semiconductors of the type Cu(In,Ga)Se{sub 2} in a quantum well solar cell structure are explored. Thin alternating layers of 50 nm CuInSe{sub 2} and CuGaSe{sub 2} were grown epitaxially on a GaAs(100) substrate. The optical properties of a resulting structure of three layers indicate charge carrier confinement in the low band gap CuInSe{sub 2} layer. By compositional analysis interdiffusion of In and Ga at the interfaces was found. The compositional profile was converted into a conduction-band diagram, for which the quantization of energy levels was numerically confirmed using the effective-mass approximation. The results provide a promising basis for the future development of chalcopyrite-type quantum well structures and their application, i.e. in quantum well solar cells. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Nanobump assembly for plasmonic organic solar cells

    Science.gov (United States)

    Song, Hyung-Jun; Jung, Kinam; Lee, Gunhee; Ko, Youngjun; Lee, Jong-Kwon; Choi, Mansoo; Lee, Changhee

    2014-10-01

    We demonstrate novel plasmonic organic solar cells (OSCs) by embedding an easy processible nanobump assembly (NBA) for harnessing more light. The NBA is consisted of precisely size-controlled Ag nanoparticles (NPs) generated by an aerosol process at atmospheric pressure and thermally deposited molybdenum oxide (MoO3) layer which follows the underlying nano structure of NPs. The active layer, spin-casted polymer blend solution, has an undulated structure conformably covering the NBA structure. To find the optimal condition of the NBA structure for enhancing light harvest as well as carrier transfer, we systematically investigate the effect of the size of Ag NPs and the MoO3 coverage on the device performance. It is observed that the photocurrent of device increases as the size of Ag NP increases owing to enhanced plasmonic and scattering effect. In addition, the increased light absorption is effectively transferred to the photocurrent with small carrier losses, when the Ag NPs are fully covered by the MoO3 layer. As a result, the NBA structure consisted of 40 nm Ag NPs enclosed by 20 nm MoO3 layer leads to 18% improvement in the power conversion efficiency compared to the device without the NBA structure. Therefore, the NBA plasmonic structure provides a reliable and efficient light harvesting in a broad range of wavelength, which consequently enhances the performance of organic solar cells.

  9. Processes for chalcopyrite-based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Lux-Steiner, M.C.; Ennaoui, A.; Fischer, C.-H.; Jaeger-Waldau, A.; Klaer, J.; Klenk, R.; Koenenkamp, R.; Matthes, T.; Scheer, R.; Siebentritt, S.; Weidinger, A. [Hahn-Meitner-Institut Berlin GmbH (Germany)

    2000-02-21

    This contribution deals with the investigations of chalcopyrite solar cells. Main attention is paid to absorber materials with band gaps larger than 1.5 eV. Besides the different efforts to modify and optimise stoichiometric CuInS{sub 2} films, novel deposition technologies for CuGaSe{sub 2} films and buffer layers as well as alternative buffer layers were studied and compared. With ZnSe as alternative buffer layer on Cu(InGa)(S,Se){sub 2} absorbers developed by SSI Camarillo and Siemens Solar, Munich, total area efficiencies up to 13.7% and active area efficiencies up to 15.7% could be reached, respectively. For CuInS{sub 2} two important results were achieved. The efficiency of Cu-poor CuInS{sub 2} cells could be increased to 8.3%. Standard Cu-rich prepared devices led to a new record efficiency of 12.5%. (orig.)

  10. Hybrid Perovskite/Perovskite Heterojunction Solar Cells.

    Science.gov (United States)

    Hu, Yinghong; Schlipf, Johannes; Wussler, Michael; Petrus, Michiel L; Jaegermann, Wolfram; Bein, Thomas; Müller-Buschbaum, Peter; Docampo, Pablo

    2016-06-28

    Recently developed organic-inorganic hybrid perovskite solar cells combine low-cost fabrication and high power conversion efficiency. Advances in perovskite film optimization have led to an outstanding power conversion efficiency of more than 20%. Looking forward, shifting the focus toward new device architectures holds great potential to induce the next leap in device performance. Here, we demonstrate a perovskite/perovskite heterojunction solar cell. We developed a facile solution-based cation infiltration process to deposit layered perovskite (LPK) structures onto methylammonium lead iodide (MAPI) films. Grazing-incidence wide-angle X-ray scattering experiments were performed to gain insights into the crystallite orientation and the formation process of the perovskite bilayer. Our results show that the self-assembly of the LPK layer on top of an intact MAPI layer is accompanied by a reorganization of the perovskite interface. This leads to an enhancement of the open-circuit voltage and power conversion efficiency due to reduced recombination losses, as well as improved moisture stability in the resulting photovoltaic devices.

  11. TEMPERATUREEFFECT OFELECTRICALPROPERTIES OF CIGS SOLAR CELL

    Directory of Open Access Journals (Sweden)

    A. M. Ferouani

    2015-07-01

    Full Text Available In this paper we are interested in studying the copper–indium–gallium–selenium (CIGS solar cells sandwiched between cadmium sulfide (CdS and ZnO as buffer layers, and Molybdenum (Mo. Thus, we report our simulation results using the capacitance simulator (SCAPS in terms of layer thickness, absorber layer band gap and operating temperature to find out the optimum choice. An efficiency of 20.61% (with Voc of 635.2mV, Jsc of 44.08 mA/cm2 and fill factor of 0.73 has been achieved with CdS used as buffer layer as the reference case. It is also found that the high efficiency CIGS cells with the low temperature were a very high efficiency conversion.

  12. Scalable fabrication of perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhen; Klein, Talysa R.; Kim, Dong Hoe; Yang, Mengjin; Berry, Joseph J.; van Hest, Maikel F. A. M.; Zhu, Kai

    2018-03-27

    Perovskite materials use earth-abundant elements, have low formation energies for deposition and are compatible with roll-to-roll and other high-volume manufacturing techniques. These features make perovskite solar cells (PSCs) suitable for terawatt-scale energy production with low production costs and low capital expenditure. Demonstrations of performance comparable to that of other thin-film photovoltaics (PVs) and improvements in laboratory-scale cell stability have recently made scale up of this PV technology an intense area of research focus. Here, we review recent progress and challenges in scaling up PSCs and related efforts to enable the terawatt-scale manufacturing and deployment of this PV technology. We discuss common device and module architectures, scalable deposition methods and progress in the scalable deposition of perovskite and charge-transport layers. We also provide an overview of device and module stability, module-level characterization techniques and techno-economic analyses of perovskite PV modules.

  13. FY 2000 report on the results of the development of technology for commercialization of the photovoltaic power system - Development of production technology of thin film solar cells. Separate Volume 1. Development of production technology of low cost/large area modules (Investigational study on the commercialization analysis); 2000 nendo New sunshine keikaku seika hokokusho. Taiyoko hatsuden system jitsuyoka gijutsu kaihatsu {sup H}akumaku taiyodenchi no seizo gijutsu kaihatsu{sup -} Tei cost dai menseki mojuru seizo gijutsu kaihatsu (Jitsuyoka kaiseki ni kansuru chosa kenkyu) - 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    For the purpose of supporting the study of commercialization of thin film solar cells for electric power use and the study of production technology of thin film solar cells, survey of the technical trend of the thin film solar cell was conducted, and the FY 2000 results were summed up. The typical Si system thin film solar cell is the amorphous Si solar cell, and the quantity production has already started in Japan and abroad. Further, with the aim of making use of characteristics of the amorphous Si solar cell and also making its defects up, the development of Si thin film solar cell using microcrystal Si and polycrystal Si is greatly expected. Among those, attention is paid to the hybrid type that was proposed for the remarkable improvement in the conversion efficiency of amorphous Si solar cell. In the compound thin film system, the Cu(InGa)Se{sub 2}(CiGS) solar cell was put on the market as product by SSI, though the market scale is small. Further, as to the CdTe thin film solar cell, trial manufacture of the large area module was made in view of the housing use. In addition, there was seen great progress in the color sensitized cell and organic semiconducting solar cell mainly in the U.S. and Europe. (NEDO)

  14. Study on the fabrication of silicon nanoparticles in an amorphous silicon light absorbing layer for solar cell applications

    International Nuclear Information System (INIS)

    Park, Joo Hyung; Song, Jin Soo; Lee, Jae Hee; Lee, Jeong Chul

    2012-01-01

    Hydrogenated amorphous-silicon (a-Si:H) thin-film solar cells have advantages of relatively simple technology, less material consumption, higher absorption ratio compared to crystalline silicon, and low cost due to the use of cheaper substrates rather than silicon wafers. However, together with those advantages, amorphous-silicon thin-film solar cells face several issues such as a relatively lower efficiency, a relatively wider bandgap, and the Staebler-Wronski effect (SWE) compared to other competing materials (i.e., crystalline silicon, CdTe, Cu(In x Ga (1-x) )Se 2 (CIGS), etc.). As a remedy for those drawbacks and a way to enhance the cell conversion efficiency at the same time, the employment of crystalline silicon nanoparticles (Si-NPs) in the a-Si matrix is proposed to organize the quantum-dot (QD) structure as the light-absorbing layer. This structure of the light absorbing layer consists of single-crystal Si-NPs in an a-Si:H thin-film matrix. The single-crystal Si-NPs are synthesized by using SiH 4 gas decomposition with CO 2 laser pyrolysis, and the sizes of Si-NPs are calibrated to control their bandgaps. The synthesized size-controlled Si-NPs are directly transferred to another chamber to form a QD structure by using co-deposition of the Si-NPs and the a-Si:H matrix. Transmission electron microscopy (TEM) analyses are employed to verify the sizes and the crystalline properties of the Si-NPs alone and of the Si-NPs in the a-Si:H matrix. The TEM results show successful co-deposition of size-controlled Si-NPs in the a-Si:H matrix, which is meaningful because it suggests the possibility of further enhancement of the a-Si:H solar-cell structure and of tandem structure applications by using a single element.

  15. Metal Matrix Composite Solar Cell Metallization

    Directory of Open Access Journals (Sweden)

    Wilt David M.

    2017-01-01

    Full Text Available Advanced solar cells are moving to ever thinner formats in order to save mass and in some cases improve performance. As cells are thinned, the possibility that they may fracture or cleave due to mechanical stresses is increased. Fractures of the cell can degrade the overall device performance if the fracture propagates through the contact metallization, which frequently occurs. To address this problem, a novel semiconductor metallization system based on multi-walled carbon nanotube (CNT reinforcement, termed metal matrix composite (MMC metallization is under investigation. Electro-mechanical characterization of MMC films demonstrate their ability to provide electrical conductivity over >40 micron wide cracks in the underlying semiconductor, with the carbon nanotubes bridging the gap. In addition, these materials show a “self-healing” behaviour, electrically reconnecting at ~30 microns when strained past failure. Triple junction (TJ space cells with MMC metallization demonstrated no loss in Jsc after intentional fracture, whereas TJ cells with conventional metallization suffer up to 50% Jsc loss.

  16. Ninth Workshop on Crystalline Silicon Solar Cell Materials and Processes: Extended Abstracts and Papers of the Workshop, 9-11 August 1999, Breckenridge, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Sopori, B.L.; Gee, J.; Kalejs, J.; Saitoh, R.; Stavola, M.; Swanson, D.; Tan, T.; Weber, E.; Werner, J.

    2000-08-04

    Since 1997, the PV sales have exceeded 100 MW/yr with > 85% of the production coming from silicon photovoltaics (Si-PV). As the PV demands increase in the new millennium, there will be a host of challenges to Si-PV. The challenges will arise in developing strategies for cost reduction, increased production, higher throughput per manufacturing line, new sources of low-cost Si, and introduction of new manufacturing processes for cell fabrication. At the same time, newer thin-film technologies, based on CdTe and CIS, will come on board posing new competition. With these challenges come new opportunities for the Si-PV-to detach itself from the microelectronics industry, to embark on an aggressive program in thin-film Si solar cells, and to try new approaches to process monitoring. The 9th Workshop on Crystalline Silicon Solar Cell Materials and Processes addressed these issues in a number of sessions. In addition to covering the usual topics of impurity gettering, defects, passivation, and solar cell processing, there were sessions on poly feedstock, mechanical properties of Si, metallization, and process monitoring.

  17. Numerical modelling of CIGS/CdS solar cell

    Science.gov (United States)

    Devi, Nisha; Aziz, Anver; Datta, Shouvik

    2018-05-01

    In this work, we design and analyze the Cu(In,Ga)Se2 (CIGS) solar cell using simulation software "Solar Cell Capacitance Simulator in One Dimension (SCAPS-1D)". The conventional CIGS solar cell uses various layers, like intrinsic ZnO/Aluminium doped ZnO as transparent oxide, antireflection layer MgF2, and electron back reflection (EBR) layer at CIGS/Mo interface for good power conversion efficiency. We replace this conventional model by a simple model which is easy to fabricate and also reduces the cost of this cell because of use of lesser materials. The new designed model of CIGS solar cell is ITO/CIGS/OVC/CdS/Metal contact, where OVC is ordered vacancy compound. From this simple structure, even at very low illumination we are getting good results. We simulate this CIGS solar cell model by varying various physical parameters of CIGS like thickness, carrier density, band gap and temperature.

  18. Advanced laser processing for industrial solar cell manufacturing (ALPINISM)

    Energy Technology Data Exchange (ETDEWEB)

    Mason, N.B.; Fieret, J. [Exitech Ltd. (United Kingdom)

    2006-05-04

    The study was aimed at improving methods for the manufacture of high efficiency solar cells and thereby increase production rates. The project focused on the laser grooved buried contact solar cell (LGBC) which is produced by high-speed laser machining. The specific objectives were (i) to optimise the laser technology for high speed processing; (ii) to optimise the solar cell process conditions for high speed processing; (iii) to produce a prototype tool and demonstrate high throughput; and (iv) to demonstrate increased cell efficiency using laser processing of rear contact. Essentially, all the objectives were met and Exitech have already sold six production tools and one research tool developed in this study. In addition, it was found that laser processing at the rear cell surface offers the prospect of LGBC solar cells with an efficiency of 20 per cent. BP Solar Limited carried out this work under contract to the DTI.

  19. Review of Polymer, Dye-Sensitized, and Hybrid Solar Cells

    Directory of Open Access Journals (Sweden)

    S. N. F. Mohd-Nasir

    2014-01-01

    Full Text Available The combination of inorganic nanoparticles semiconductor, conjugated polymer, and dye-sensitized in a layer of solar cell is now recognized as potential application in developing flexible, large area, and low cost photovoltaic devices. Several conjugated low bandgap polymers, dyes, and underlayer materials based on the previous studies are quoted in this paper, which can provide guidelines in designing low cost photovoltaic solar cells. All of these materials are designed to help harvest more sunlight in a wider range of the solar spectrum besides enhancing the rate of charge transfer in a device structure. This review focuses on developing solid-state dye-synthesized, polymer, and hybrid solar cells.

  20. Experiment Based Teaching of Solar Cell Operation and Characterization Using the SolarLab Platform

    DEFF Research Database (Denmark)

    Spataru, Sergiu; Sera, Dezso; Kerekes, Tamas

    2014-01-01

    interfaces for exploring different solar cell principles and topics. The exercises presented in the current paper have been adapted from the original exercises developed for the SolarLab platform and are currently included in the Photovoltaic Power Systems courses (MSc and PhD level) taught at the Department...... which is a laboratory teaching tool developed at Transylvania University of Brasov. Using this platform, solar cells can be characterized under various illumination, temperature and angle of light incidence. Additionally, the SolarLab platform includes guided exercises and intuitive graphical user......Experiment based teaching methods are a great way to get students involved and interested in almost any topic. This paper presents such a hands-on approach for teaching solar cell operation principles along with characterization and modelling methods. This is achieved with the SolarLab platform...

  1. Electron Acceptor Materials Engineering in Colloidal Quantum Dot Solar Cells

    KAUST Repository

    Liu, Huan

    2011-07-15

    Lead sulfide colloidal quantum dot (CQD) solar cells with a solar power conversion efficiency of 5.6% are reported. The result is achieved through careful optimization of the titanium dioxide electrode that serves as the electron acceptor. Metal-ion-doped sol-gel-derived titanium dioxide electrodes produce a tunable-bandedge, well-passivated materials platform for CQD solar cell optimization. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Silicon Thin-Film Solar Cells

    Directory of Open Access Journals (Sweden)

    Guy Beaucarne

    2007-01-01

    with plasma-enhanced chemical vapor deposition (PECVD. In spite of the fundamental limitation of this material due to its disorder and metastability, the technology is now gaining industrial momentum thanks to the entry of equipment manufacturers with experience with large-area PECVD. Microcrystalline Si (also called nanocrystalline Si is a material with crystallites in the nanometer range in an amorphous matrix, and which contains less defects than amorphous silicon. Its lower bandgap makes it particularly appropriate as active material for the bottom cell in tandem and triple junction devices. The combination of an amorphous silicon top cell and a microcrystalline bottom cell has yielded promising results, but much work is needed to implement it on large-area and to limit light-induced degradation. Finally thin-film polysilicon solar cells, with grain size in the micrometer range, has recently emerged as an alternative photovoltaic technology. The layers have a grain size ranging from 1 μm to several tens of microns, and are formed at a temperature ranging from 600 to more than 1000∘C. Solid Phase Crystallization has yielded the best results so far but there has recently been fast progress with seed layer approaches, particularly those using the aluminum-induced crystallization technique.

  3. Photoelectrode nanostructure dye-sensitized solar cell | Kimpa ...

    African Journals Online (AJOL)

    This study used carica papaya (pawpaw leaf) extracts as natural organic dye for dye sensitized solar cell (DSSC). Pawpaw leaf extract is rich in chlorophyll and was extracted using ethanol as the extracting solvent and serve as the sensitizer for DSSC. The specialty of the DSSC relative to other types of solar cells is the use ...

  4. Topology optimization of front metallization patterns for solar cells

    NARCIS (Netherlands)

    Gupta, D.K.; Langelaar, M.; Barink, M.; Keulen, F. van

    2015-01-01

    This paper presents the application of topology optimization (TO) for designing the front electrode patterns for solar cells. Improving the front electrode design is one of the approaches to improve the performance of the solar cells. It serves to produce the voltage distribution for the front

  5. Microstructure and Mechanical Aspects of Multicrystalline Silicon Solar Cells

    NARCIS (Netherlands)

    Popovich, V.A.

    2013-01-01

    Due to pressure from the photovoltaic industry to decrease the cost of solar cell production, there is a tendency to reduce the thickness of silicon wafers. Unfortunately, wafers contain defects created by the various processing steps involved in solar cell production, which significantly reduce the

  6. Characteristics of dye-sensitized solar cells using natural dye

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, Shoji, E-mail: furukawa@cse.kyutech.ac.j [Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka-shi, Fukuoka-ken 820-8502 (Japan); Iino, Hiroshi; Iwamoto, Tomohisa; Kukita, Koudai; Yamauchi, Shoji [Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka-shi, Fukuoka-ken 820-8502 (Japan)

    2009-11-30

    Dye-sensitized solar cells are expected to be used for future clean energy. Recently, most of the researchers in this field use Ruthenium complex as dye in the dye-sensitized solar cells. However, Ruthenium is a rare metal, so the cost of the Ruthenium complex is very high. In this paper, various dye-sensitized solar cells have been fabricated using natural dye, such as the dye of red-cabbage, curcumin, and red-perilla. As a result, it was found that the conversion efficiency of the solar cell fabricated using the mixture of red-cabbage and curcumin was about 0.6% (light source: halogen lamp), which was larger than that of the solar cells using one kind of dye. It was also found that the conversion efficiency was about 1.0% for the solar cell with the oxide semiconductor film fabricated using polyethylene glycol (PEG) whose molecular weight was 2,000,000 and red-cabbage dye. This indicates that the cost performance (defined by [conversion efficiency]/[cost of dye]) of the latter solar cell (dye: red-cabbage) is larger by more than 50 times than that of the solar cell using Ruthenium complex, even if the effect of the difference between the halogen lamp and the standard light source is taken into account.

  7. STUDY OF PERFORMANCES OF ORGANIC SOLAR CELLS BY ...

    African Journals Online (AJOL)

    30 juin 2011 ... results of analysis of performances of organic solar cells by using what one call the datamining materials. ... Keywords: organic solar cells, gap energie, effiency, PCA. Author Correspondence .... oubli est malencontreux car le type de données disponibles influence toujours la direction de la recherche.

  8. Five-Junction Solar Cell Optimization Using Silvaco Atlas

    Science.gov (United States)

    2017-09-01

    SOLAR CELL OPTIMIZATION USING SILVACO ATLAS by Raymond J. Kilway II September 2017 Thesis Advisor: Sherif Michael Second Reader: Matthew......12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) Multi-junction solar cells have given rise to compact high-efficiency photovoltaic

  9. Phenothiazine-Based Dyes in Solar Cell Technology

    Directory of Open Access Journals (Sweden)

    Andrei Bejan

    2017-12-01

    Full Text Available Phenothiazine is a fused heterocyclic ring with strong electron-donating character which makes it an important building block for designing organic materials for solar cells applications. The present paper reviews the most recent achievements of phenothiazine-based compounds as dyes in solar cells, with special emphasis on the structure – performance relationship.

  10. Pathways to a New Efficiency Regime for Organic Solar Cells

    NARCIS (Netherlands)

    Koster, L. Jan Anton; Shaheen, Sean E.; Hummelen, Jan C.

    2012-01-01

    Three different theoretical approaches are presented to identify pathways to organic solar cells with power conversion efficiencies in excess of 20%. A radiation limit for organic solar cells is introduced that elucidates the role of charge-transfer (CT) state absorption. Provided this CT action is

  11. Transparent conductive oxides for thin-film silicon solar cells

    NARCIS (Netherlands)

    Löffler, J.

    2005-01-01

    This thesis describes research on thin-film silicon solar cells with focus on the transparent conductive oxide (TCO) for such devices. In addition to the formation of a transparent and electrically conductive front electrode for the solar cell allowing photocurrent collection with low ohmic losses,

  12. Low-cost production of solar-cell panels

    Science.gov (United States)

    Bickler, D. B.; Gallagher, B. D.; Sanchez, L. E.

    1980-01-01

    Large-scale production model combines most modern manufacturing techniques to produce silicon-solar-cell panels of low costs by 1982. Model proposes facility capable of operating around the clock with annual production capacity of 20 W of solar cell panels.

  13. Stability and degradation mechanisms in organic solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ecker, Bernhard

    2012-04-26

    This thesis deals with stability improvements and the investigation of degradation mechanisms in organic solar cells. Organic solar cells have been in the focus of extensive academic research for over almost two decades and are currently entering the market in small scale applications. For successful large scale applications, next to the improvement of the power conversion efficiency, the stability of organic solar cells has to be increased. This thesis is dedicated to the investigation of novel materials and architectures to study stability-related issues and degradation mechanisms in order to contribute to the basic understanding of the working principles of organic solar cells. Here, impedance spectroscopy, a frequency domain technique, is used to gain information about stability and degradation mechanisms in organic solar cells. In combination with systematic variations in the preparation of solar cells, impedance spectroscopy gives the possibility to differentiate between interface and bulk dominated effects. Additionally, impedance spectroscopy gives access to the dielectric properties of the device, such as capacitance. This offers among other things the opportunity to probe the charge carrier concentration and the density of states. Another powerful way of evaluation is the combination of experimentally obtained impedance spectra with equivalent circuit modelling. The thesis presents results on novel materials and solar cell architectures for efficient hole and electron extraction. This indicates the importance of knowledge over interlayers and interfaces for improving both the efficiency and stability of organic solar cells.

  14. Silicon solar cells made by ion implantation and glow discharge

    International Nuclear Information System (INIS)

    Ponpon, J.P.; Siffert, P.

    1975-01-01

    Three different methods of silicon solar cell preparation are considered and investigated: low energy implantation, glow discharge and prebombarded Schottky barriers. The properties of the contact layers realized by these processes are compared in terms of junction depth and sheet resistance. Preliminary results show the usefulness of these techniques for terrestrial solar cell realization [fr

  15. 3D-Printed external light traps for solar cells

    NARCIS (Netherlands)

    van Dijk, L.; Paetzold, U.W.; Blab, Gerhard; Marcus, E.A.P.; Oostra, A.J.; van de Groep, J.; Polman, A.; Schropp, R.E.I.; Di Vece, M.

    2015-01-01

    We demonstrate a universally applicable 3D-printed external light trap for solar cells. We placed a macroscopic external light trap made of smoothened, silver coated plastic at the sun-facing surface of different types of solar cells. The trap consists of a reflective parabolic concentrator on top

  16. Electrical equivalent model of intermediate band solar cell using ...

    Indian Academy of Sciences (India)

    presents a structure of IBSC based on ZnTe:O. The proposed model uses irradiance and temperature as ... of solar cells. They are based on different processes and properties such as photon recycling, ... The MATLAB interface was used .... ioral model of an arbitrary solar cell to amend the PSPICE simulation performance.

  17. Principles and operation of crystalline and amorphous silicon solar cells

    International Nuclear Information System (INIS)

    Chambouleyron, I.

    1983-01-01

    This paper deals with the fundamental aspects of photovoltaic energy conversion. Crystalline silicon solar cell physics together with design criteria and conversion losses are discussed. The general properties of hydrogenated amorphous silicon and the principles of a-Si:H solar cell operation are briefly reviewed. New trends in amorphous materials of photovoltaic interest and novel device structures are finally presented. (Author) [pt

  18. Applications of ``PV Optics`` for solar cell and module design

    Energy Technology Data Exchange (ETDEWEB)

    Sopori, B.L.; Madjdpour, J.; Chen, W. [National Renewable Energy Lab., Golden, CO (United States)

    1998-09-01

    This paper describes some applications of a new optics software package, PV Optics, developed for the optical design of solar cells and modules. PV Optics is suitable for the analysis and design of both thick and thin solar cells. It also includes a feature for calculation of metallic losses related to contacts and back reflectors.

  19. Assessment of the dye-sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, R. D. [Center for Basic Sciences, National Renewable Energy Laboratory, MIS 3211, 1617 Cole Boulevard, Golden, CO 80401 (United States)

    2002-09-01

    The field of solar electricity, or photovoltaics (PV), is rich in that there are many materials and concepts for converting sunlight into electricity. The technologies accepted as conventional are those well along in the process of commercialization. The dye-sensitized solar cell, developed in the 1990s, is a nonconventional solar electric technology that has attracted much attention, perhaps a result of its record cell efficiency above 10%. This paper reviews the technology, discusses new research results and approaches presented at a recent symposium of many of the world's important dye solar cell researchers, and presents an assessment of the dye-sensitized solar cell in a comparison with current conventional solar electric technologies. It concludes the dye solar cell has potential for becoming a cost-effective means for producing electricity, capable of competing with available solar electric technologies and, eventually, with today's conventional power technologies. But it is a relatively new technology and faces many hurdles on the path to commercialization. Because of its potential, this assessment recommends further funding for research and development (RandD) of the dye-sensitized solar cell technology on the basis of the promising technical characteristics of the technology, a strong US and worldwide research base, positive industry interest, and today's relatively small funding allocation for its RandD. (Author)

  20. Monolithic Perovskite Silicon Tandem Solar Cells with Advanced Optics

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, Jan C.; Bett, Alexander J.; Bivour, Martin; Blasi, Benedikt; Eisenlohr, Johannes; Kohlstadt, Markus; Lee, Seunghun; Mastroianni, Simone; Mundt, Laura; Mundus, Markus; Ndione, Paul; Reichel, Christian; Schubert, Martin; Schulze, Patricia S.; Tucher, Nico; Veit, Clemens; Veurman, Welmoed; Wienands, Karl; Winkler, Kristina; Wurfel, Uli; Glunz, Stefan W.; Hermle, Martin

    2016-11-14

    For high efficiency monolithic perovskite silicon tandem solar cells, we develop low-temperature processes for the perovskite top cell, rear-side light trapping, optimized perovskite growth, transparent contacts and adapted characterization methods.

  1. Studying nanotoxic effects of CdTe quantum dots in Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Cecilia Stahl Vieira

    2011-03-01

    Full Text Available Semiconductor nanoparticles, such as quantum dots (QDs, were used to carry out experiments in vivo and ex vivo with Trypanosoma cruzi. However, questions have been raised regarding the nanotoxicity of QDs in living cells, microorganisms, tissues and whole animals. The objective of this paper was to conduct a QD nanotoxicity study on living T. cruzi protozoa using analytical methods. This was accomplished using in vitro experiments to test the interference of the QDs on parasite development, morphology and viability. Our results show that after 72 h, a 200 μM cadmium telluride (CdTe QD solution induced important morphological alterations in T. cruzi, such as DNA damage, plasma membrane blebbing and mitochondrial swelling. Flow cytometry assays showed no damage to the plasma membrane when incubated with 200 μM CdTe QDs for up to 72 h (propidium iodide cells, giving no evidence of classical necrosis. Parasites incubated with 2 μM CdTe QDs still proliferated after seven days. In summary, a low concentration of CdTe QDs (2 μM is optimal for bioimaging, whereas a high concentration (200 μM CdTe could be toxic to cells. Taken together, our data indicate that 2 μM QD can be used for the successful long-term study of the parasite-vector interaction in real time.

  2. In-situ X-ray Nanocharacterization of Defect Kinetics in Chalcogenide Solar Cell Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bertoni, Mariana [Arizona State Univ., Tempe, AZ (United States); Lai, Barry [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Masser, Jorg [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Buonassisi, Tonio [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2016-09-21

    For decades the optimization of polycrystalline absorbers has been done using an Edisonian approach, where trial and error and complex design of experiments in large parameter spaces have driven efficiencies to the record values we see today – CIGS at 22.5%, 22.1% for CdTe, 21.3% for high purity multi-crystalline silicon. Appropriate growth parameters are critical to ensure good quality crystals with low concentration of structural defects - low dislocation density and large grain sizes. However, to bridge the gap between the efficiencies today and the fundamental Shockley-Queisser limit for these materials a much more fundamental understanding of the role and interaction between composition, structure, defect density and electrical properties is required. In recent years multiple novel characterization techniques have shown the potential that nanoscale characterization can have in deciphering the composition of grain boundaries in materials like CIGS and CdTe. However, high resolution has come at the cost of small sampling areas and number of specimens, making it extremely difficult to draw conclusions based on the characteristic small sampling sizes. The missing links thus far have been: (1) the lack of statistical meaningfulness of the nanosclae studies and (2) the direct correlation of compositional variations to electrical performance with nanoscale resolution. In this work we present the use of synchrotron-based nano-X-ray fluorescence microscopy (nano-XRF), x-ray absorption nanospectroscopy (nano-XAS) coupled with nano-x-ray beam induced current (nano-XBIC) as ideal tools for investigating elemental, chemical and electrical properties of large areas of solar cell materials at the sub-micron scale with very high sensitivity. We show how the technique can provide statistical valuable information regarding the elemental segregation in CIGS and the direct correlation to current collection. For example, we demonstrate that Cu and Ga (and with that, CGI and GGI

  3. Photoelectrochemistry of metallo-octacarboxyphthalocyanines for the development of dye solar cells

    CSIR Research Space (South Africa)

    Mphahlele, N

    2011-09-01

    Full Text Available Significant attention is being paid to dye solar cells (DSCs) as the next generation in solar cell technology for their low cost alternative as compared to solid state solar cells....

  4. AlGaAs top solar cell for mechanical attachment in a multi-junction tandem concentrator solar cell stack

    Science.gov (United States)

    Dinetta, L. C.; Hannon, M. H.; Cummings, J. R.; Mcneeley, J. B.; Barnett, Allen M.

    1990-01-01

    Free-standing, transparent, tunable bandgap AlxGa1-xAs top solar cells have been fabricated for mechanical attachment in a four terminal tandem stack solar cell. Evaluation of the device results has demonstrated 1.80 eV top solar cells with efficiencies of 18 percent (100 X, and AM0) which would yield stack efficiencies of 31 percent (100 X, AM0) with a silicon bottom cell. When fully developed, the AlxGa1-xAs/Si mechanically-stacked two-junction solar cell concentrator system can provide efficiencies of 36 percent (AM0, 100 X). AlxGa1-xAs top solar cells with bandgaps from 1.66 eV to 2.08 eV have been fabricated. Liquid phase epitaxy (LPE) growth techniques have been used and LPE has been found to yield superior AlxGa1-xAs material when compared to molecular beam epitaxy and metal-organic chemical vapor deposition. It is projected that stack assembly technology will be readily applicable to any mechanically stacked multijunction (MSMJ) system. Development of a wide bandgap top solar cell is the only feasible method for obtaining stack efficiencies greater than 40 percent at AM0. System efficiencies of greater than 40 percent can be realized when the AlGaAs top solar cell is used in a three solar cell mechanical stack.

  5. Innovative laser based solar cell scribing

    Science.gov (United States)

    Frei, Bruno; Schneeberger, Stefan; Witte, Reiner

    2011-03-01

    The solar photovoltaic market is continuously growing utilizing boths crystalline silicon (c-Si) as well as thin film technologies. This growth is directly dependant on the manufacturing costs for solar cells. Factors for cost reduction are innovative ideas for an optimization of precision and throughput. Lasers are excellent tools to provide highly efficient processes with impressive accuracy. They need to be used in combination with fast and precise motion systems for a maximum gain in the manufacturing process, yielding best cost of ownership. In this article such an innovative solution is presented for laser scribing in thin film Si modules. A combination of a new glass substrate holding system combined with a fast and precise motion system is the foundation for a cost effective scribing machine. In addition, the advantages of fiber lasers in beam delivery and beam quality guarantee not only shorter setup and down times but also high resolution and reproducibility for the scribing processes P1, P2 and P3. The precision of the whole system allows to reduce the dead zone to a minimum and therefore to improve the efficiency of the modules.

  6. Environmentally benign silicon solar cell manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Tsuo, Y.S. [National Renewable Energy Lab., Golden, CO (United States); Gee, J.M. [Sandia National Labs., Albuquerque, NM (United States); Menna, P. [National Agency for New Technologies Energy and Environment, Portici (Italy); Strebkov, D.S.; Pinov, A.; Zadde, V. [Intersolarcenter, Moscow (Russian Federation)

    1998-09-01

    The manufacturing of silicon devices--from polysilicon production, crystal growth, ingot slicing, wafer cleaning, device processing, to encapsulation--requires many steps that are energy intensive and use large amounts of water and toxic chemicals. In the past two years, the silicon integrated-circuit (IC) industry has initiated several programs to promote environmentally benign manufacturing, i.e., manufacturing practices that recover, recycle, and reuse materials resources with a minimal consumption of energy. Crystalline-silicon solar photovoltaic (PV) modules, which accounted for 87% of the worldwide module shipments in 1997, are large-area devices with many manufacturing steps similar to those used in the IC industry. Obviously, there are significant opportunities for the PV industry to implement more environmentally benign manufacturing approaches. Such approaches often have the potential for significant cost reduction by reducing energy use and/or the purchase volume of new chemicals and by cutting the amount of used chemicals that must be discarded. This paper will review recent accomplishments of the IC industry initiatives and discuss new processes for environmentally benign silicon solar-cell manufacturing.

  7. Dye-sensitized solar cells based on nanostructured zinc oxide

    Energy Technology Data Exchange (ETDEWEB)

    Conradt, Jonas; Maier-Flaig, Florian; Sartor, Janos; Fallert, Johannes [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Szmytkowski, Jedrzej; Kalt, Heinz [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Center for Functional Nanostructures (CFN), Karlsruhe (Germany); Reinhard, Manuel; Colsmann, Alexander [Karlsruhe Institute of Technology (KIT), Lichttechnisches Institut, Karlsruhe (Germany); Lemmer, Uli [Center for Functional Nanostructures (CFN), Karlsruhe (Germany); Karlsruhe Institute of Technology (KIT), Lichttechnisches Institut, Karlsruhe (Germany); Balaban, Teodor Silviu [Center for Functional Nanostructures (CFN), Karlsruhe (Germany); Karlsruhe Institute of Technology (KIT), Institute for Nanotechnology, Karlsruhe (Germany)

    2009-07-01

    Hybrid solar cells represent a promising (cost-efficient) alternative to pure inorganic solar cells. We present dye-sensitized solar cells (DSSC) which are based on a zinc oxide (ZnO) electrode covered with a ruthenium dye. Our work focuses on the morphology of the ZnO electrode and its impact on the photovoltaic performance of the solar cell. Nanocrystalline ZnO powder layers and arrays of nanorods are incorporated into the DSSCs. The ZnO nanorods are grown by vapor transport deposition. The morphology and doping concentration of the rods can be controlled by the choice of substrate material, growth condition and catalytic metal layers. The nanorod arrays are expected to fasten the electron transport towards the anode and thereby improve the solar cell efficiency. In addition, novel self-assembling (porphyrin) dyes are tested as sensitizer within a DSSC.

  8. Design and Photovoltaic Properties of Graphene/Silicon Solar Cell

    Science.gov (United States)

    Xu, Dikai; Yu, Xuegong; Yang, Lifei; Yang, Deren

    2018-04-01

    Graphene/silicon (Gr/Si) Schottky junction solar cells have attracted widespread attention for the fabrication of high-efficiency and low-cost solar cells. However, their performance is still limited by the working principles of Schottky junctions. Modulating the working mechanism of the solar cells into a quasi p-n junction has advantages, including higher open-circuit voltage (V OC) and less carrier recombination. In this study, Gr/Si quasi p-n junction solar cells were formed by inserting a tunneling Al2O3 interlayer in-between graphene and silicon, which led to obtain the PCE up to 8.48% without antireflection or chemical doping techniques. Our findings could pave a new way for the development of Gr/Si solar cells.

  9. Emerging Semitransparent Solar Cells: Materials and Device Design.

    Science.gov (United States)

    Tai, Qidong; Yan, Feng

    2017-09-01

    Semitransparent solar cells can provide not only efficient power-generation but also appealing images and show promising applications in building integrated photovoltaics, wearable electronics, photovoltaic vehicles and so forth in the future. Such devices have been successfully realized by incorporating transparent electrodes in new generation low-cost solar cells, including organic solar cells (OSCs), dye-sensitized solar cells (DSCs) and organometal halide perovskite solar cells (PSCs). In this review, the advances in the preparation of semitransparent OSCs, DSCs, and PSCs are summarized, focusing on the top transparent electrode materials and device designs, which are all crucial to the performance of these devices. Techniques for optimizing the efficiency, color and transparency of the devices are addressed in detail. Finally, a summary of the research field and an outlook into the future development in this area are provided. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Simple processing of high efficiency silicon solar cells

    International Nuclear Information System (INIS)

    Hamammu, I.M.; Ibrahim, K.

    2006-01-01

    Cost effective photovoltaic devices have been an area research since the development of the first solar cells, as cost is the major factor in their usage. Silicon solar cells have the biggest share in the photovoltaic market, though silicon os not the optimal material for solar cells. This work introduces a simplified approach for high efficiency silicon solar cell processing, by minimizing the processing steps and thereby reducing cost. The suggested procedure might also allow for the usage of lower quality materials compared to the one used today. The main features of the present work fall into: simplifying the diffusion process, edge shunt isolation and using acidic texturing instead of the standard alkaline processing. Solar cells of 17% efficiency have been produced using this procedure. Investigations on the possibility of improving the efficiency and using less quality material are still underway

  11. Business, market and intellectual property analysis of polymer solar cells

    DEFF Research Database (Denmark)

    Damgaard Nielsen, Torben; Cruickshank, C.; Foged, S.

    2010-01-01

    and manufacturing cost leaves little room for competition on the thin film photovoltaic market. However, polymer solar cells do enable the competitive manufacture of low cost niche products and is viewed as financially viable in its currently available form in a large volume approximation. Finally, it is found......The business potential of polymer solar cells is reviewed and the market opportunities analyzed on the basis of the currently reported and projected performance and manufacturing cost of polymer solar cells. Possible new market areas are identified and described. An overview of the present patent...... and intellectual property situation is also given and a patent map of polymer solar cells is drawn in a European context. It is found that the business potential of polymer solar cells is large when taking the projections for future performance into account while the currently available performance...

  12. Neutral- and Multi-Colored Semitransparent Perovskite Solar Cells.

    Science.gov (United States)

    Lee, Kyu-Tae; Guo, L Jay; Park, Hui Joon

    2016-04-11

    In this review, we summarize recent works on perovskite solar cells with neutral- and multi-colored semitransparency for building-integrated photovoltaics and tandem solar cells. The perovskite solar cells exploiting microstructured arrays of perovskite "islands" and transparent electrodes-the latter of which include thin metallic films, metal nanowires, carbon nanotubes, graphenes, and transparent conductive oxides for achieving optical transparency-are investigated. Moreover, the perovskite solar cells with distinctive color generation, which are enabled by engineering the band gap of the perovskite light-harvesting semiconductors with chemical management and integrating with photonic nanostructures, including microcavity, are discussed. We conclude by providing future research directions toward further performance improvements of the semitransparent perovskite solar cells.

  13. Workshop - Solar cells and daylight. Solar cell house. House building with integrated solar cell systems; Workshop - Solceller og dagslys. Solcellehus. Boligbyggeri med integrerede solcelleanlaeg

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Mio; Hansen, Ellen Kathrine

    2005-04-15

    The workshop 'Solar cells and daylight' at Aarhus School of Architecture aimed at studying and developing architectural potentials of integrating solar cell systems in building components for future house building. The aim of the process was to stress that technical conditions such as energy technological component design might work as central points of support in the future shaping and organisation of qualitative and functional design of houses. (BA)

  14. The performance of silicon solar cells operated in liquids

    International Nuclear Information System (INIS)

    Wang Yiping; Fang Zhenlei; Zhu Li; Huang Qunwu; Zhang Yan; Zhang Zhiying

    2009-01-01

    Better performance can be achieved when the bare silicon solar cells are immersed into liquids for the enhanced heat removing. In this study, the performance of solar cells immersed in liquids was examined under simulated sunlight. To distinguish the effects of the liquid optic and electric properties on the solar cells, a comparison between immersion of the solar module and the bare solar cells was carried out. It was found that the optic properties of the liquids can cause minor efficiency changes on the solar cells, while the electric properties of the liquids, the molecular polarizable and ions, are responsible for the most of the changes. The bare solar cells immersed in the non-polar silicon oil have the best performance. The accelerated life tests were carried out at 150 deg. C high temperature and under 200 W/m 2 ultraviolet light irradiation, respectively. It was found that the silicon oil has good stability. This study can give support on the cooling of the concentrated photovoltaic systems by immersing the solar cells in the liquids directly

  15. Metal nanoparticles for thin film solar cells

    DEFF Research Database (Denmark)

    Gritti, Claudia

    and intensity depends on the nanoparticle’s size, shape, and local dielectric environment, thus absorption enhancement in a defined wavelength range can be achieved varying these properties (tuning the LSP resonance). Even though scattering enhancement of photons above the gap of the semiconductor is useful...... to increase light trapping and can come along regardless, we aim, as first target, to absorb forbidden (for the semiconductor) photons by the NPs which can excite hot electrons inside the metal NP and emit them directly into the conduction band of the solar cell semiconductor, without going through...... the promotion of electrons from the valence band of the semiconductor. The photoemission would extend the spectral response of the photovoltaic device. Thus, NPs are placed at the metal/semiconductor interface (in order to exploit the localization characteristic of the LSP enhancement) and are used as active...

  16. Stability and Degradation of Polymer Solar cells

    DEFF Research Database (Denmark)

    Norrman, Kion

    The current state-of-the-art allows for roll-to-roll manufacture of polymer solar cells in high volume with stability and efficiency sufficient to grant success in low-energy applications. However, further improvement is needed for the successful application of the devices in real life applications....... This is obtained by detailed knowledge of the degradation mechanisms. Methods to compare and standardize device stability are urgently needed. Methodologies to study failure mechanism that are based on physical processes (e.g. morphological changes) are well-established. However, methodologies to study chemical...... degradation mechanisms are currently scarce. An overview of known degradation mechanisms will be presented and discussed in relation to state-of-the-art methodologies to study failure mechanisms with focus on chemical degradation....

  17. Development in fiscal 1999 of technologies to put photovoltaic power generation systems into practical use. Volume 1. Development of thin film solar cell manufacturing technologies (Development of technologies to manufacture low-cost large-area modules and survey and research on analyzing how to put products into practical use); 1999 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu (tei cost daimenseki module seizo gijutsu kaihatsu (jitsuyoka kaiseki ni kansuru chosa kenkyu 1))

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    With an objective to assist research and development to put thin film solar cells for power use into practical use and a research to put thin film solar cell manufacturing technologies into practical use, survey and research have been performed on trends in the technologies inside and outside the country. Characteristic points in thin film solar cells during the current fiscal year include: expansion of production scale of amorphous silicon solar cells, rapid progress in poly-crystalline silicon thin film solar cell technologies, and enhancement of performance in large-area modules in the a-Si, CIGS, and CdTe systems. In the trends in research and development of amorphous systems, expectation is heightening on elucidation of optical deterioration phenomena, and establishment of suppression technologies thereof. Although the highest efficiency was not renewed in thin film solar cells of small areas, progress was seen in the post-stabilization efficiency in large-area modules. A thin film solar cell manufacturing plant having an annual production capacity of 20 MW was put into operation in October in Japan. Micro (poly) crystalline silicon based solar cells have high possibility of being compatible in cost reduction and performance improvement, and energetic researches are being carried out on them in recent years as the most promising candidate of the next generation solar cells. (NEDO)

  18. Strategies to reduce the open-circuit voltage deficit in Cu2ZnSn(S,Se)4 thin film solar cells

    Science.gov (United States)

    Kim, Jekyung; Shin, Byungha

    2017-09-01

    Cu2ZnSn(S,Se)4 thin film solar cell has attracted significant attention in thin film solar cell technologies considering its low-cost, non-toxicity, and earth-abundance. However, the highest efficiency still remains at 12.6%, far below the theoretical efficiency of Shockley-Queisser (SQ) limit of around 30%. The limitation behind such shortcoming in the device performance was reported to stem primarily from a high V oc deficit compared to other thin film solar cell technologies such as CdTe or Cu(In,Ga)Se2 (CIGS), whose origins are attributed to the prevalence of band tailing from cation disordering as well as to the high recombination at the interfaces. In this report, systematic studies on the causes of a high V oc deficit and associated remarkable approaches to achieve high V oc have been reviewed, provided with a guidance on the future direction of CZTSSe research in resolving the high V oc deficit issue. [Figure not available: see fulltext.

  19. Silicon solar cells: Past, present and the future

    Science.gov (United States)

    Lee, Youn-Jung; Kim, Byung-Sung; Ifitiquar, S. M.; Park, Cheolmin; Yi, Junsin

    2014-08-01

    There has been a great demand for renewable energy for the last few years. However, the solar cell industry is currently experiencing a temporary plateau due to a sluggish economy and an oversupply of low-quality cells. The current situation can be overcome by reducing the production cost and by improving the cell is conversion efficiency. New materials such as compound semiconductor thin films have been explored to reduce the fabrication cost, and structural changes have been explored to improve the cell's efficiency. Although a record efficiency of 24.7% is held by a PERL — structured silicon solar cell and 13.44% has been realized using a thin silicon film, the mass production of these cells is still too expensive. Crystalline and amorphous silicon — based solar cells have led the solar industry and have occupied more than half of the market so far. They will remain so in the future photovoltaic (PV) market by playing a pivotal role in the solar industry. In this paper, we discuss two primary approaches that may boost the silicon — based solar cell market; one is a high efficiency approach and the other is a low cost approach. We also discuss the future prospects of various solar cells.

  20. Silicon solar cells: past, present and the future

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. J.; Kim, B. S.; Ifitiquar, S. M.; Park, C. M.; Yi, J. S. [Sungkyunkwan University, Suwon (Korea, Republic of)

    2014-08-15

    There has been a great demand for renewable energy for the last few years. However, the solar cell industry is currently experiencing a temporary plateau due to a sluggish economy and an over supply of low-quality cells. The current situation can be overcome by reducing the production cost and by improving the cell is conversion efficiency. New materials such as compound semiconductor thin films have been explored to reduce the fabrication cost, and structural changes have been explored to improve the cell's efficiency. Although a record efficiency of 24.7% is held by a PERL - structured silicon solar cell and 13.44% has been realized using a thin silicon film, the mass production of these cells is still too expensive. Crystalline and amorphous silicon - based solar cells have led the solar industry and have occupied more than half of the market so far. They will remain so in the future photovoltaic (PV) market by playing a pivotal role in the solar industry. In this paper, we discuss two primary approaches that may boost the silicon - based solar cell market; one is a high efficiency approach and the other is a low cost approach. We also discuss the future prospects of various solar cells.

  1. Photovoltaic Test and Demonstration Project. [for solar cell power systems

    Science.gov (United States)

    Forestieri, A. F.; Brandhorst, H. W., Jr.; Deyo, J. N.

    1976-01-01

    The Photovoltaic Test and Demonstration Project was initiated by NASA in June, 1975, to develop economically feasible photovoltaic power systems suitable for a variety of terrestrial applications. Objectives include the determination of operating characteristic and lifetimes of a variety of solar cell systems and components and development of methodology and techniques for accurate measurements of solar cell and array performance and diagnostic measurements for solar power systems. Initial work will be concerned with residential applications, with testing of the first prototype system scheduled for June, 1976. An outdoor 10 kW array for testing solar power systems is under construction.

  2. Perovskite-Based Solar Cells: Materials, Methods, and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Di Zhou

    2018-01-01

    Full Text Available A novel all-solid-state, hybrid solar cell based on organic-inorganic metal halide perovskite (CH3NH3PbX3 materials has attracted great attention from the researchers all over the world and is considered to be one of the top 10 scientific breakthroughs in 2013. The perovskite materials can be used not only as light-absorbing layer, but also as an electron/hole transport layer due to the advantages of its high extinction coefficient, high charge mobility, long carrier lifetime, and long carrier diffusion distance. The photoelectric power conversion efficiency of the perovskite solar cells has increased from 3.8% in 2009 to 22.1% in 2016, making perovskite solar cells the best potential candidate for the new generation of solar cells to replace traditional silicon solar cells in the future. In this paper, we introduce the development and mechanism of perovskite solar cells, describe the specific function of each layer, and focus on the improvement in the function of such layers and its influence on the cell performance. Next, the synthesis methods of the perovskite light-absorbing layer and the performance characteristics are discussed. Finally, the challenges and prospects for the development of perovskite solar cells are also briefly presented.

  3. Analysis of Operating Temperature of the Polycrystalline Solar Cell

    Directory of Open Access Journals (Sweden)

    Vladimír GÁLL

    2017-12-01

    Full Text Available This work deals with the solar cells with orientation on the calculation of operating temperature of the polycrystalline solar cell, which is under actual load. Operating conditions have a significant effect on the efficiency of solar cells. In the summer with increasing temperature, the efficiency decreases. In the winter, efficiency and output voltage are rising. The operating temperature is determined by intensity of solar radiation, the types of materials used by construction and operating condition. The aim of this work was simplify of the calculation of operating temperature of solar cells. The result of this work is a derived equation that allows a more accurate and faster calculation this temperature with using Matlab software.

  4. Comparative modeling of InP solar cell structures

    Science.gov (United States)

    Jain, R. K.; Weinberg, I.; Flood, D. J.

    1991-01-01

    The comparative modeling of p(+)n and n(+)p indium phosphide solar cell structures is studied using a numerical program PC-1D. The optimal design study has predicted that the p(+)n structure offers improved cell efficiencies as compared to n(+)p structure, due to higher open-circuit voltage. The various cell material and process parameters to achieve the maximum cell efficiencies are reported. The effect of some of the cell parameters on InP cell I-V characteristics was studied. The available radiation resistance data on n(+)p and p(+)p InP solar cells are also critically discussed.

  5. Solar Cell and Array Technology Development for NASA Solar Electric Propulsion Missions

    Science.gov (United States)

    Piszczor, Michael; McNatt, Jeremiah; Mercer, Carolyn; Kerslake, Tom; Pappa, Richard

    2012-01-01

    NASA is currently developing advanced solar cell and solar array technologies to support future exploration activities. These advanced photovoltaic technology development efforts are needed to enable very large (multi-hundred kilowatt) power systems that must be compatible with solar electric propulsion (SEP) missions. The technology being developed must address a wide variety of requirements and cover the necessary advances in solar cell, blanket integration, and large solar array structures that are needed for this class of missions. Th is paper will summarize NASA's plans for high power SEP missions, initi al mission studies and power system requirements, plans for advanced photovoltaic technology development, and the status of specific cell and array technology development and testing that have already been conducted.

  6. Dye-sensitized solar cells and solar module using polymer electrolytes: Stability and performance investigations

    Directory of Open Access Journals (Sweden)

    Jilian Nei de Freitas

    2006-01-01

    Full Text Available We present recent results on solid-state dye-sensitized solar cell research using a polymer electrolyte based on a poly(ethylene oxide derivative. The stability and performance of the devices have been improved by a modification in the method of assembly of the cells and by the addition of plasticizers in the electrolyte. After 30 days of solar irradiation (100 mW cm-2 no changes in the cell's efficiency were observed using this new method. The effect of the active area size on cell performance and the first results obtained for the first solar module composed of 4.5 cm2 solid-state solar cells are also presented.

  7. A verified technique for calibrating space solar cells

    Science.gov (United States)

    Anspaugh, Bruce

    1987-01-01

    Solar cells have been flown on high-altitude balloons for over 24 years, to produce solar cell standards that can be used to set the intensity of solar simulators. The events of a typical balloon calibration flight are reported. These are: the preflight events, including the preflight cell measurements and the assembly of the flight cells onto the solar tracker; the activities at the National Scientific Balloon Facility in Palestine, Texas, including the preflight calibrations, the mating of the tracker and cells onto the balloon, preparations for launch, and the launch; the payload recovery, which includes tracking the balloon by aircraft, terminating the flight, and retrieving the payload. In 1985, the cells flow on the balloon were also flown on a shuttle flight and measured independently. The two measurement methods are compared and shown to agree within 1 percent.

  8. Radiation resistance of solar cells for space application, 1

    International Nuclear Information System (INIS)

    Mitsui, Hiroshi; Tanaka, Ryuichi; Sunaga, Hiromi

    1989-07-01

    A 50-μm thick ultrathin silicon solar cell and a 280-μm thick high performance AlGaAs/GaAs solar cell with high radiation resistance have been recently developed by National Space Development Agency of Japan (NASDA). In order to study the radiation resistance of these cells, a joint research was carried out between Japan Atomic Energy Research Institute (JAERI) and NASDA from 1984 through 1987. In this research, the irradiation method of electron beams, the effects of the irradiation conditions on the deterioration of solar cells by electron beams, and the annealing effects of the radiation damage in solar cells were investigated. This paper is the first one of a series of reports of the joint research. In this paper, the space radiation environment which artificial satellites will encounter, the solar cells used, and the experimental methods are described. In addition to these, the results of the study on the irradiation procedure of electron beams are reported. In the study of the irradiation method of electron beams, three methods, that is, the fixed irradiation method, the moving irradiation method, and the spot irradiation method were examined. In the fixed irradiation method and moving one, stationary solar cells and solar cells moving by conveyer were irradiated by scanning electron beams, respectively. On the other hand, in the spot irradiation method, stationary solar cells were irradiated by non-scanning steady electron beams. It was concluded that the fixed irradiation method was the most proper method. In addition to this, in this study, some pieces of information were obtained with respect to the changes in the electrical characteristics of solar cells caused by the irradiation of electron beams. (author) 52 refs

  9. Amorphous and microcrystalline silicon applied in very thin tandem solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Schicho, Sandra

    2011-07-28

    Thin-film solar cells are fabricated by low-cost production processes, and are therefore an alternative to conventionally used wafer solar cells based on crystalline silicon. Due to the different band gaps, tandem cells that consist of amorphous (a-Si:H) and microcrystalline ({mu}c-Si:H) single junction solar cells deposited on top of each other use the solar spectrum much more efficient than single junction solar cells. The silicon layers are usually deposited on TCO (Transparent Conductive Oxide)-coated glass and metal- or plastic foils. Compared to the CdTe and CIGS based thin-film technologies, silicon thin-film solar cells have the advantage that no limitation of raw material supply is expected and no toxic elements are used. Nevertheless, the production cost per Wattpeak is the decisive factor concerning competitiveness and can be reduced by, e.g., shorter deposition times or reduced material consumption. Both cost-reducing conceptions are simultaneously achieved by reducing the a-Si:H and {mu}c-Si:H absorber layer thicknesses in a tandem device. In the work on hand, the influence of an absorber layer thickness reduction up to 77% on the photovoltaic parameters of a-Si:H/{mu}c-Si:H tandem solar cells was investigated. An industry-oriented Radio Frequency Plasma-Enhanced Chemical Vapour Deposition (RF-PECVD) system was used to deposit the solar cells on glass substrates coated with randomly structured TCO layers. The thicknesses of top and bottom cell absorber layers were varied by adjusting the deposition time. Reduced layer thicknesses lead to lower absorption and, hence, to reduced short-circuit current densities which, however, are partially balanced by higher open-circuit voltages and fill factors. Furthermore, by using very thin amorphous top cells, the light-induced degradation decreases tremendously. Accordingly, a thickness reduction of 75% led to an efficiency loss of only 21 %. By adjusting the parameters for the deposition of a-Si:H top cells, a

  10. Indacenodithienothiophene-Based Ternary Organic Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gasparini, Nicola, E-mail: nicola.gasparini@fau.de [Institute of Materials for Electronics and Energy Technology (I-MEET), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen (Germany); García-Rodríguez, Amaranda [Macromolecular Chemistry Group (buwmakro), Institute for Polymer Technology, BergischeUniversität Wuppertal, Wuppertal (Germany); Prosa, Mario [Istituto per lo Studio dei Materiali Nanostrutturati (ISMN), Consiglio Nazionale delle Ricerche (CNR), Bologna (Italy); Bayseç, Şebnem; Palma-Cando, Alex [Macromolecular Chemistry Group (buwmakro), Institute for Polymer Technology, BergischeUniversität Wuppertal, Wuppertal (Germany); Katsouras, Athanasios; Avgeropoulos, Apostolos [Department of Materials Science Engineering, University of Ioannina, Ioannina (Greece); Pagona, Georgia; Gregoriou, Vasilis G. [Advent Technologies SA, Patras Science Park, Patra (Greece); National Hellenic Research Foundation (NHRF), Athens (Greece); Chochos, Christos L. [Department of Materials Science Engineering, University of Ioannina, Ioannina (Greece); Advent Technologies SA, Patras Science Park, Patra (Greece); Allard, Sybille; Scherf, Ulrich [Macromolecular Chemistry Group (buwmakro), Institute for Polymer Technology, BergischeUniversität Wuppertal, Wuppertal (Germany); Brabec, Christoph J. [Institute of Materials for Electronics and Energy Technology (I-MEET), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen (Germany); Bavarian Center for Applied Energy Research (ZAE Bayern), Erlangen (Germany); Ameri, Tayebeh, E-mail: nicola.gasparini@fau.de [Institute of Materials for Electronics and Energy Technology (I-MEET), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen (Germany)

    2017-01-13

    One of the key aspects to achieve high efficiency in ternary bulk-hetorojunction solar cells is the physical and chemical compatibility between the donor materials. Here, we report the synthesis of a novel conjugated polymer (P1) containing alternating pyridyl[2,1,3]thiadiazole between two different donor fragments, dithienosilole and indacenodithienothiophene (IDTT), used as a sensitizer in a host system of indacenodithieno[3,2-b]thiophene,2,3-bis(3-(octyloxy)phenyl)quinoxaline (PIDTTQ) and [6,6]-phenyl C{sub 70} butyric acid methyl ester (PC{sub 71}BM). We found that the use of the same IDTT unit in the host and guest materials does not lead to significant changes in the morphology of the ternary blend compared to the host binary. With the complementary use of optoelectronic characterizations, we found that the ternary cells suffer from a lower mobility-lifetime (μτ) product, adversely impacting the fill factor. However, the significant light harvesting in the near infrared region improvement, compensating the transport losses, results in an overall power conversion efficiency enhancement of ~7% for ternary blends as compared to the PIDTTQ:PC{sub 71}BM devices.

  11. Studies of bulk heterojunction solar cells

    Science.gov (United States)

    Cossel, Raquel; McIntyre, Max; Tzolov, Marian

    We are studying bulk heterojunction solar cells that were fabricated using a mixture of PCPDTBT and PCBM­C60. The impedance data of the cells in dark responded like a simple RC circuit. The value of the dielectric constant derived from these results is consistent with the values reported in the literature for these materials. We are showing that the parallel resistance in the equivalent circuit of linear lump elements can be interpreted using the DC current­voltage measurements. The impedance spectra under light illumination indicated the existence of additional polarization. This extra feature can be described by a model that includes a series RC circuit in parallel with the equivalent circuit for a device in dark. The physical interpretation of the additional polarization is based on photo­generated charges getting trapped in wells, which have a characteristic relaxation time corresponding to the observed break frequency in the impedance spectra. We have studied the influence of the anode and cathode interface on this phenomena, either by using different interface materials, or by depositing the metal electrode while the substate is heated.

  12. Modelling solar cells with thermal phenomena taken into account

    International Nuclear Information System (INIS)

    Górecki, K; Górecki, P; Paduch, K

    2014-01-01

    The paper is devoted to modelling properties of solar cells. The authors' electrothermal model of such cells is described. This model takes into account the influence of temperature on its characteristics. Some results of calculations and measurements of selected solar cells are presented and discussed. The good agreement between the results of calculations and measurements was obtained, which proves the correctness of the elaborated model.

  13. Process development for high-efficiency silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Gee, J.M.; Basore, P.A.; Buck, M.E.; Ruby, D.S.; Schubert, W.K.; Silva, B.L.; Tingley, J.W.

    1991-12-31

    Fabrication of high-efficiency silicon solar cells in an industrial environment requires a different optimization than in a laboratory environment. Strategies are presented for process development of high-efficiency silicon solar cells, with a goal of simplifying technology transfer into an industrial setting. The strategies emphasize the use of statistical experimental design for process optimization, and the use of baseline processes and cells for process monitoring and quality control. 8 refs.

  14. Formation of photovoltaic modules based on polycrystalline solar cells

    OpenAIRE

    L. A. Dobrzański; A. Drygała; A. Januszka

    2009-01-01

    Purpose: The main aim of the paper is formation of photovoltaic modules and analysis of their main electric parameters.Design/methodology/approach: Photovoltaic modules were produced from four polycrystalline silicon solar cells, that were cut and next joined in series. Soft soldering technique and copper-tin strip were used for joining cells.Findings: In order to provide useful power for any application, the individual solar cells must be connected together to give the appropriate current an...

  15. Low cost thin film poly-silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This report presents the results of a project to design and develop a high density plasma based thin-film poly-silicon (TFPS) deposition system based on PQL proprietary advanced plasma technology to produce semiconductor quality TFPS for fabricating a TFPS solar cell. Details are given of the TFPS deposition system, the material development programme, solar cell structure, and cell efficiencies. The reproducibility of the deposition process and prospects for commercial exploitation are discussed.

  16. Molecular and Nanoscale Engineering of High Efficiency Excitonic Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Jenekhe, Samson A. [Univ. of Washington, Seattle, WA (United States); Ginger, David S. [Univ. of Washington, Seattle, WA (United States); Cao, Guozhong [Univ. of Washington, Seattle, WA (United States)

    2016-01-15

    We combined the synthesis of new polymers and organic-inorganic hybrid materials with new experimental characterization tools to investigate bulk heterojunction (BHJ) polymer solar cells and hybrid organic-inorganic solar cells during the 2007-2010 period (phase I) of this project. We showed that the bulk morphology of polymer/fullerene blend solar cells could be controlled by using either self-assembled polymer semiconductor nanowires or diblock poly(3-alkylthiophenes) as the light-absorbing and hole transport component. We developed new characterization tools in-house, including photoinduced absorption (PIA) spectroscopy, time-resolved electrostatic force microscopy (TR-EFM) and conductive and photoconductive atomic force microscopy (c-AFM and pc-AFM), and used them to investigate charge transfer and recombination dynamics in polymer/fullerene BHJ solar cells, hybrid polymer-nanocrystal (PbSe) devices, and dye-sensitized solar cells (DSSCs); we thus showed in detail how the bulk photovoltaic properties are connected to the nanoscale structure of the BHJ polymer solar cells. We created various oxide semiconductor (ZnO, TiO2) nanostructures by solution processing routes, including hierarchical aggregates and nanorods/nanotubes, and showed that the nanostructured photoanodes resulted in substantially enhanced light-harvesting and charge transport, leading to enhanced power conversion efficiency of dye-sensitized solar cells.

  17. Single-Walled Carbon Nanotubes in Solar Cells.

    Science.gov (United States)

    Jeon, Il; Matsuo, Yutaka; Maruyama, Shigeo

    2018-01-22

    Photovoltaics, more generally known as solar cells, are made from semiconducting materials that convert light into electricity. Solar cells have received much attention in recent years due to their promise as clean and efficient light-harvesting devices. Single-walled carbon nanotubes (SWNTs) could play a crucial role in these devices and have been the subject of much research, which continues to this day. SWNTs are known to outperform multi-walled carbon nanotubes (MWNTs) at low densities, because of the difference in their optical transmittance for the same current density, which is the most important parameter in comparing SWNTs and MWNTs. SWNT films show semiconducting features, which make SWNTs function as active or charge-transporting materials. This chapter, consisting of two sections, focuses on the use of SWNTs in solar cells. In the first section, we discuss SWNTs as a light harvester and charge transporter in the photoactive layer, which are reviewed chronologically to show the history of the research progress. In the second section, we discuss SWNTs as a transparent conductive layer outside of the photoactive layer, which is relatively more actively researched. This section introduces SWNT applications in silicon solar cells, organic solar cells, and perovskite solar cells each, from their prototypes to recent results. As we go along, the science and prospects of the application of solar cells will be discussed.

  18. Thin film solar cells grown by organic vapor phase deposition

    Science.gov (United States)

    Yang, Fan

    Organic solar cells have the potential to provide low-cost photovoltaic devices as a clean and renewable energy resource. In this thesis, we focus on understanding the energy conversion process in organic solar cells, and improving the power conversion efficiencies via controlled growth of organic nanostructures. First, we explain the unique optical and electrical properties of organic materials used for photovoltaics, and the excitonic energy conversion process in donor-acceptor heterojunction solar cells that place several limiting factors of their power conversion efficiency. Then, strategies for improving exciton diffusion and carrier collection are analyzed using dynamical Monte Carlo models for several nanostructure morphologies. Organic vapor phase deposition is used for controlling materials crystallization and film morphology. We improve the exciton diffusion efficiency while maintaining good carrier conduction in a bulk heterojunction solar cell. Further efficiency improvement is obtained in a novel nanocrystalline network structure with a thick absorbing layer, leading to the demonstration of an organic solar cell with 4.6% efficiency. In addition, solar cells using simultaneously active heterojunctions with broad spectral response are presented. We also analyze the efficiency limits of single and multiple junction organic solar cells, and discuss the challenges facing their practical implementations.

  19. Business, market and intellectual property analysis of polymer solar cells

    International Nuclear Information System (INIS)

    Nielsen, Torben D.; Krebs, Frederik C.; Cruickshank, Craig; Foged, Soeren; Thorsen, Jesper

    2010-01-01

    The business potential of polymer solar cells is reviewed and the market opportunities analyzed on the basis of the currently reported and projected performance and manufacturing cost of polymer solar cells. Possible new market areas are identified and described. An overview of the present patent and intellectual property situation is also given and a patent map of polymer solar cells is drawn in a European context. It is found that the business potential of polymer solar cells is large when taking the projections for future performance into account while the currently available performance and manufacturing cost leaves little room for competition on the thin film photovoltaic market. However, polymer solar cells do enable the competitive manufacture of low cost niche products and is viewed as financially viable in its currently available form in a large volume approximation. Finally, it is found that the polymer solar cell technology is very poorly protected in Europe with the central patents being valid in only France, Germany, the Netherlands and the United Kingdom. Several countries with a large potential for PV such as Portugal and Greece are completely open and have apparently no relevant patents. This is viewed as a great advantage for the possible commercialization of polymer solar cells in a European setting as the competition for the market will be based on the manufacturing performance rather than domination by a few patent stakeholders. (author)

  20. Research and development for evaluation system of solar cell

    Energy Technology Data Exchange (ETDEWEB)

    1986-08-01

    In order to evaluate the performance and capability of solar cell properly and impartially, the evaluation systems for the performance and reliability have been assured. The results are as follows. 1. Development for performance evaluation method; (1) The international comparisons of standard solar cell calibration methods and our method has been assured to be mostly near to the average value. (2) Experimental solar cell has been made and the indoors and outdoors evaluation of solar cell module have become to be possible with same accuracy. (3) As the spectro-radiometer of high performance have been developed, the measurements of the output of the solar cell module have become possible, monitering spectrum of wide range of natural solar beam. (4) With use of several kinds of standard solar cell, measurement errors have been assured. (5) As for nominal operating cell temperature of module, experimental researches have been done indoors and outdoors and the diffeneces have been assured. 2. Development of reliability evaluation method; (1) In outdoor exposure test, the basic data of the accelerating degradation test have been accumulated and it has been assured that the degradation of crystal type is few. (2) By the acceleration degradation test with use of weathermeter, and temperature and humidity cycling test device, the proceses of degradation have been assured. (3) In the processes of enviromental tests and mechanical strength tests, remarkable degradation has not been recognized.(1 tab)