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Sample records for semiconductor electrolyte photovoltaic

  1. Semiconductor electrolyte photovoltaic energy converter

    Science.gov (United States)

    Anderson, W. W.; Anderson, L. B.

    1975-01-01

    Feasibility and practicality of a solar cell consisting of a semiconductor surface in contact with an electrolyte are evaluated. Basic components and processes are detailed for photovoltaic energy conversion at the surface of an n-type semiconductor in contact with an electrolyte which is oxidizing to conduction band electrons. Characteristics of single crystal CdS, GaAs, CdSe, CdTe and thin film CdS in contact with aqueous and methanol based electrolytes are studied and open circuit voltages are measured from Mott-Schottky plots and open circuit photo voltages. Quantum efficiencies for short circuit photo currents of a CdS crystal and a 20 micrometer film are shown together with electrical and photovoltaic properties. Highest photon irradiances are observed with the GaAs cell.

  2. Organic Semiconductor Photovoltaics

    Science.gov (United States)

    Sariciftci, Niyazi Serdar

    2005-03-01

    Recent developments on organic photovoltaic elements are reviewed. Semiconducting conjugated polymers and molecules as well as nanocrystalline inorganic semiconductors are used in composite thin films. The photophysics of such photoactive devices is based on the photoinduced charge transfer from donor type semiconducting molecules onto acceptor type molecules such as Buckminsterfullerene, C60 and/or nanoparticles. Similar to the first steps in natural photosynthesis, this photoinduced electron transfer leads to a number of potentially interesting applications which include sensitization of the photoconductivity and photovoltaic phenomena. Examples of photovoltaic architectures are discussed with their potential in terrestrial solar energy conversion. Several materials are introduced and discussed for their photovoltaic activities. Furthermore, nanomorphology has been investigated with AFM, SEM and TEM. The morphology/property relationship for a given photoactive system is found to be a major effect.

  3. Charge regulation at semiconductor-electrolyte interfaces.

    Science.gov (United States)

    Fleharty, Mark E; van Swol, Frank; Petsev, Dimiter N

    2015-07-01

    The interface between a semiconductor material and an electrolyte solution has interesting and complex electrostatic properties. Its behavior will depend on the density of mobile charge carriers that are present in both phases as well as on the surface chemistry at the interface through local charge regulation. The latter is driven by chemical equilibria involving the immobile surface groups and the potential determining ions in the electrolyte solution. All these lead to an electrostatic potential distribution that propagate such that the electrolyte and the semiconductor are dependent on each other. Hence, any variation in the charge density in one phase will lead to a response in the other. This has significant implications on the physical properties of single semiconductor-electrolyte interfaces and on the electrostatic interactions between semiconductor particles suspended in electrolyte solutions. The present paper expands on our previous publication (Fleharty et al., 2014) and offers new results on the electrostatics of single semiconductor interfaces as well as on the interaction of charged semiconductor colloids suspended in electrolyte solution. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. 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 ...

  5. Electrolytic Hydrogen obtaining by a photovoltaic source

    International Nuclear Information System (INIS)

    Pasculete, E.; Condrea, F.; Stanoiu, L.

    2005-01-01

    At present, the developed countries allocate large funds for the financing of some global programs for fundamental and applicative research for development of hydrogen non-conventional production technologies. One of these technologies is the photo-assisted electrolysis. This technology is adopted in the research, which results are presented in this paper. The experimental model includes as basic equipment 100 W photovoltaic source, electrolysis battery press filter type, control unit of the electric energy discharged, accumulator, hydrogen storage unit. Five types of material have been tested for the electrolysis cell diaphragm: asbestos; Netrom- unwoven material from fibers of polypropylene; ion changing composite membrane - polysulfone support with an active layer of sulfonated poly-sulfone (PSS/PSJ) and poly-sulfone support with an active layer of sulfonated poly-eter cetone (SPEEK/PSf); ion-exchange membrane made from sulfonated poly-eter cetone (SPEEK). The graphics and results from the test system are presented. The analysis of the experimental results lead to the establishment of the optimal configuration of battery and of the operational conditions of the assembly. The experimental results give the opportunity to obtain electrolytic hydrogen with a photovoltaic source, in an efficient system, and promote the Romanian research at a level of a demonstrative installation

  6. Modeling of semiconductor nanostructures and semiconductor-electrolyte interfaces

    International Nuclear Information System (INIS)

    Birner, Stefan

    2011-01-01

    The main objective of Part I is to give an overview of some of the methods that have been implemented into the nextnano 3 software. Examples are discussed that give insight into doping, strain and mobility. Applications of the single-band Schroedinger equation include three-dimensional superlattices, and a qubit that is manipulated by a magnetic field. Results of the multi-band k.p method are presented for HgTe-CdTe and InAs-GaSb superlattices, and for a SiGe-Si quantum cascade structure. Particular focus is put on a detailed description of the contact block reduction (CBR) method that has been developed within our research group. By means of this approach, quantum transport in the ballistic limit in one, two and three dimensions can be calculated. I provide a very detailed description of the algorithm and present several well documented examples that highlight the key points of this method. Calculating quantum transport in three dimensions is a very challenging task where computationally efficient algorithms - apart from the CBR method - are not available yet. Part II describes the methods that I have implemented into the nextnano 3 software for calculating systems that consist of a combination of semiconductor materials and liquids. These biosensors have a solid-electrolyte interface, and the charges in the solid and in the electrolyte are coupled to each other through the Poisson-Boltzmann equation. I apply this model to a silicon based protein sensor, where I solve the Schroedinger equation together with the Poisson-Boltzmann equation self-consistently, and compare theoretical results with experiment. Furthermore, I have developed a novel approach to model the charge density profiles at semiconductor-electrolyte interfaces that allows us to distinguish hydrophobic and hydrophilic interfaces. Our approach extends previous work where ion specific potentials of mean force describe the distribution of ion species at the interface. I apply this new model to recently

  7. Modeling of semiconductor nanostructures and semiconductor-electrolyte interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Birner, Stefan

    2011-11-15

    The main objective of Part I is to give an overview of some of the methods that have been implemented into the nextnano{sup 3} software. Examples are discussed that give insight into doping, strain and mobility. Applications of the single-band Schroedinger equation include three-dimensional superlattices, and a qubit that is manipulated by a magnetic field. Results of the multi-band k.p method are presented for HgTe-CdTe and InAs-GaSb superlattices, and for a SiGe-Si quantum cascade structure. Particular focus is put on a detailed description of the contact block reduction (CBR) method that has been developed within our research group. By means of this approach, quantum transport in the ballistic limit in one, two and three dimensions can be calculated. I provide a very detailed description of the algorithm and present several well documented examples that highlight the key points of this method. Calculating quantum transport in three dimensions is a very challenging task where computationally efficient algorithms - apart from the CBR method - are not available yet. Part II describes the methods that I have implemented into the nextnano{sup 3} software for calculating systems that consist of a combination of semiconductor materials and liquids. These biosensors have a solid-electrolyte interface, and the charges in the solid and in the electrolyte are coupled to each other through the Poisson-Boltzmann equation. I apply this model to a silicon based protein sensor, where I solve the Schroedinger equation together with the Poisson-Boltzmann equation self-consistently, and compare theoretical results with experiment. Furthermore, I have developed a novel approach to model the charge density profiles at semiconductor-electrolyte interfaces that allows us to distinguish hydrophobic and hydrophilic interfaces. Our approach extends previous work where ion specific potentials of mean force describe the distribution of ion species at the interface. I apply this new model

  8. Bandgap Optimization of Perovskite Semiconductors for Photovoltaic Applications.

    Science.gov (United States)

    Xiao, Zewen; Zhou, Yuanyuan; Hosono, Hideo; Kamiya, Toshio; Padture, Nitin P

    2018-02-16

    The bandgap is the most important physical property that determines the potential of semiconductors for photovoltaic (PV) applications. This Minireview discusses the parameters affecting the bandgap of perovskite semiconductors that are being widely studied for PV applications, and the recent progress in the optimization of the bandgaps of these materials. Perspectives are also provided for guiding future research in this area. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Multiband semiconductor compositions for photovoltaic devices

    Science.gov (United States)

    Walukiewicz, Wladyslaw; Yu, Kin Man; Wu, Junqiao

    2010-05-04

    The highly mismatched alloy Zn.sub.1-yMn.sub.yO.sub.xTe.sub.1-x, 0.ltoreq.ysolar energy spectrum, Zn.sub.1-yMn.sub.yO.sub.xTe.sub.1-x is a material perfectly satisfying the conditions for single-junction photovoltaics with the potential for power conversion efficiencies surpassing 50%.

  10. Tandem junction amorphous semiconductor photovoltaic cell

    Science.gov (United States)

    Dalal, Vikram L.

    1983-01-01

    A photovoltaic stack comprising at least two p.sup.+ i n.sup.+ cells in optical series, said cells separated by a transparent ohmic contact layer(s), provides a long optical path for the absorption of photons while preserving the advantageous field-enhanced minority carrier collection arrangement characteristic of p.sup.+ i n.sup.+ cells.

  11. Broadband absorption of semiconductor nanowire arrays for photovoltaic applications

    International Nuclear Information System (INIS)

    Huang, Ningfeng; Lin, Chenxi; Povinelli, Michelle L

    2012-01-01

    We use electromagnetic simulations to carry out a systematic study of broadband absorption in vertically-aligned semiconductor nanowire arrays for photovoltaic applications. We study six semiconductor materials that are commonly used for solar cells. We optimize the structural parameters of each nanowire array to maximize the ultimate efficiency. We plot the maximal ultimate efficiency as a function of height to determine how it approaches the perfect-absorption limit. We further show that the ultimate efficiencies of optimized nanowire arrays exceed those of equal-height thin films for all six materials and over a wide range of heights from 100 nm to 100 µm

  12. Molecular and polymeric organic semiconductors for applications in photovoltaic devices

    International Nuclear Information System (INIS)

    Meinhardt, G.

    2000-01-01

    Photovoltaic devices based on molecular as well as polymeric semiconductors were investigated and characterized. The organic materials presented here exhibit the advantages of low price, low processing costs and the possibility of tuning their optical properties. The photovoltaic properties were investigated by photocurrent action spectroscopy and I/V-characterization and the electric field distribution in each layer by electroabsorption spectroscopy. Single layer devices of molecular semiconductors and semiconducting polymers like methyl-substituted polyparaphenylene, CN-Ether-PPV, copper-phthalocyanine, the terryleneimide DOTer, the perylene derivatives BBP-perylene and polyBBP-perylene show low photocurrents as well as a small photovoltaic effect in their pristine form. One way to enhance the performance is to blend the active layer with molecular dopands like a soluble form of titaniumoxophthalocyanine or the aromatic macromolecule RS19 or to combine two organic semiconductors in heterostructure devices. The motivation for these experiments was the optimization of either charge transfer or energy transfer from one molecule to its neighbor molecule. A model based on the internal filter effect was used for fitting the photoresponse of single layer devices. For optimising heterostructure solar cells a more sophisticated theoretical model taking into account interference effects was used. (author)

  13. Physical aspects of ferroelectric semiconductors for photovoltaic solar energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Varo, Pilar [Departamento de Electrónica y Tecnología de Computadores, CITIC-UGR, Universidad de Granada, 18071 Granada (Spain); Bertoluzzi, Luca [Institute of Advanced Materials (INAM), Universitat Jaume I, 12006 Castelló (Spain); Bisquert, Juan, E-mail: bisquert@uji.es [Institute of Advanced Materials (INAM), Universitat Jaume I, 12006 Castelló (Spain); Department of Chemistry, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Alexe, Marin [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Coll, Mariona [Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193, Bellaterra, Catalonia (Spain); Huang, Jinsong [Department of Mechanical and Materials Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE 68588-0656 (United States); Jimenez-Tejada, Juan Antonio [Departamento de Electrónica y Tecnología de Computadores, CITIC-UGR, Universidad de Granada, 18071 Granada (Spain); Kirchartz, Thomas [IEK5-Photovoltaik, Forschungszentrum Jülich, 52425 Jülich (Germany); Faculty of Engineering and CENIDE, University of Duisburg–Essen, Carl-Benz-Str. 199, 47057 Duisburg (Germany); Nechache, Riad; Rosei, Federico [INRS—Center Énergie, Matériaux et Télécommunications, Boulevard Lionel-Boulet, Varennes, Québec, J3X 1S2 (Canada); Yuan, Yongbo [Department of Mechanical and Materials Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE 68588-0656 (United States)

    2016-10-07

    Solar energy conversion using semiconductors to fabricate photovoltaic devices relies on efficient light absorption, charge separation of electron–hole pair carriers or excitons, and fast transport and charge extraction to counter recombination processes. Ferroelectric materials are able to host a permanent electrical polarization which provides control over electrical field distribution in bulk and interfacial regions. In this review, we provide a critical overview of the physical principles and mechanisms of solar energy conversion using ferroelectric semiconductors and contact layers, as well as the main achievements reported so far. In a ferroelectric semiconductor film with ideal contacts, the polarization charge would be totally screened by the metal layers and no charge collection field would exist. However, real materials show a depolarization field, smooth termination of polarization, and interfacial energy barriers that do provide the control of interface and bulk electric field by switchable spontaneous polarization. We explore different phenomena as the polarization-modulated Schottky-like barriers at metal/ferroelectric interfaces, depolarization fields, vacancy migration, and the switchable rectifying behavior of ferroelectric thin films. Using a basic physical model of a solar cell, our analysis provides a general picture of the influence of ferroelectric effects on the actual power conversion efficiency of the solar cell device, and we are able to assess whether these effects or their combinations are beneficial or counterproductive. We describe in detail the bulk photovoltaic effect and the contact layers that modify the built-in field and the charge injection and separation in bulk heterojunction organic cells as well as in photocatalytic and water splitting devices. We also review the dominant families of ferroelectric materials that have been most extensively investigated and have provided the best photovoltaic performance.

  14. Physical aspects of ferroelectric semiconductors for photovoltaic solar energy conversion

    International Nuclear Information System (INIS)

    Lopez-Varo, Pilar; Bertoluzzi, Luca; Bisquert, Juan; Alexe, Marin; Coll, Mariona; Huang, Jinsong; Jimenez-Tejada, Juan Antonio; Kirchartz, Thomas; Nechache, Riad; Rosei, Federico; Yuan, Yongbo

    2016-01-01

    Solar energy conversion using semiconductors to fabricate photovoltaic devices relies on efficient light absorption, charge separation of electron–hole pair carriers or excitons, and fast transport and charge extraction to counter recombination processes. Ferroelectric materials are able to host a permanent electrical polarization which provides control over electrical field distribution in bulk and interfacial regions. In this review, we provide a critical overview of the physical principles and mechanisms of solar energy conversion using ferroelectric semiconductors and contact layers, as well as the main achievements reported so far. In a ferroelectric semiconductor film with ideal contacts, the polarization charge would be totally screened by the metal layers and no charge collection field would exist. However, real materials show a depolarization field, smooth termination of polarization, and interfacial energy barriers that do provide the control of interface and bulk electric field by switchable spontaneous polarization. We explore different phenomena as the polarization-modulated Schottky-like barriers at metal/ferroelectric interfaces, depolarization fields, vacancy migration, and the switchable rectifying behavior of ferroelectric thin films. Using a basic physical model of a solar cell, our analysis provides a general picture of the influence of ferroelectric effects on the actual power conversion efficiency of the solar cell device, and we are able to assess whether these effects or their combinations are beneficial or counterproductive. We describe in detail the bulk photovoltaic effect and the contact layers that modify the built-in field and the charge injection and separation in bulk heterojunction organic cells as well as in photocatalytic and water splitting devices. We also review the dominant families of ferroelectric materials that have been most extensively investigated and have provided the best photovoltaic performance.

  15. Characterization and processing of bipolar semiconductor electrodes in a dual electrolyte cell

    Energy Technology Data Exchange (ETDEWEB)

    Cattarin, S.; Musiani, M.M. [Istituto di Polarografia ed Elettrochimica Preparativa del C.N.R., Padova (Italy)

    1995-11-01

    Photoelectrochemical (PEC) processes may be induced at both faces of a bipolar semiconductor electrode without application of metal contacts by using the dual electrolyte arrangement -- metal/electrolyte 1/semiconductor/electrolyte 2/metal -- and by applying a voltage to the end metal electrodes. The possibilities of semiconductor characterization (determination of action spectra and doping level) and processing (photoetching and metal electrodeposition) are discussed on the basis of model experiments, performed with n-InP wafers. The advantages of this approach over traditional PEC and electroless techniques are discussed with particular emphasis on etching.

  16. Semiconductor nanowires for photovoltaic and photoelectrochemical energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, Neil; Yang, Peidong

    2013-01-23

    Semiconductor nanowires (NW) possess several beneficial properties for efficient conversion of solar energy into electricity and chemical energy. Due to their efficient absorption of light, short distances for minority carriers to travel, high surface-to-volume ratios, and the availability of scalable synthesis methods, they provide a pathway to address the low cost-to-power requirements for wide-scale adaptation of solar energy conversion technologies. Here we highlight recent progress in our group towards implementation of NW components as photovoltaic and photoelectrochemical energy conversion devices. An emphasis is placed on the unique properties of these one-dimensional (1D) structures, which enable the use of abundant, low-cost materials and improved energy conversion efficiency compared to bulk devices.

  17. Physics of grain boundaries in polycrystalline photovoltaic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Yanfa, E-mail: yanfa.yan@utoledo.edu; Yin, Wan-Jian; Wu, Yelong; Shi, Tingting; Paudel, Naba R. [Department of Physics and Astronomy and Wright Center for Photovoltaics Innovation and Commercialization, The University of Toledo, Ohio 43606 (United States); Li, Chen [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Poplawsky, Jonathan [The Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Wang, Zhiwei [Department of Physics and Astronomy and Wright Center for Photovoltaics Innovation and Commercialization, The University of Toledo, Ohio 43606 (United States); National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Moseley, John; Guthrey, Harvey; Moutinho, Helio; Al-Jassim, Mowafak M. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Pennycook, Stephen J. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States)

    2015-03-21

    Thin-film solar cells based on polycrystalline Cu(In,Ga)Se{sub 2} (CIGS) and CdTe photovoltaic semiconductors have reached remarkable laboratory efficiencies. It is surprising that these thin-film polycrystalline solar cells can reach such high efficiencies despite containing a high density of grain boundaries (GBs), which would seem likely to be nonradiative recombination centers for photo-generated carriers. In this paper, we review our atomistic theoretical understanding of the physics of grain boundaries in CIGS and CdTe absorbers. We show that intrinsic GBs with dislocation cores exhibit deep gap states in both CIGS and CdTe. However, in each solar cell device, the GBs can be chemically modified to improve their photovoltaic properties. In CIGS cells, GBs are found to be Cu-rich and contain O impurities. Density-functional theory calculations reveal that such chemical changes within GBs can remove most of the unwanted gap states. In CdTe cells, GBs are found to contain a high concentration of Cl atoms. Cl atoms donate electrons, creating n-type GBs between p-type CdTe grains, forming local p-n-p junctions along GBs. This leads to enhanced current collections. Therefore, chemical modification of GBs allows for high efficiency polycrystalline CIGS and CdTe thin-film solar cells.

  18. Synthesis and Characterization of Colloidal Metal and Photovoltaic Semiconductor Nanocrystals

    KAUST Repository

    Abulikemu, Mutalifu

    2014-11-05

    Metal and semiconducting nanocrystals have received a great deal of attention from fundamental scientists and application-oriented researchers due to their physical and chemical properties, which differ from those of bulk materials. Nanocrystals are essential building blocks in the development of nanostructured devices for energy conversion. Colloidal metals and metal chalcogenides have been developed for use as nanocrystal inks to produce efficient solar cells with lower costs. All high-performing photovoltaic nanocrystals contain toxic elements, such as Pb, or scarce elements, such as In; thus, the production of solution-processable nanocrystals from earth-abundant materials using environmentally benign synthesis and processing methods has become a major challenge for the inorganic semiconductor-based solar field. This dissertation, divided into two parts, addresses several aspects of these emerging challenges. The first portion of the thesis describes the synthesis and characterization of nanocrystals of antimony sulfide, which is composed of non-scarce and non-toxic elements, and examines their performance in photovoltaic devices. The effect of various synthetic parameters on the final morphology is explored. The structural, optical and morphological properties of the nanocrystals were investigated, and Sb2S3 nanocrystal-based solid-state semiconductor-sensitized solar cells were fabricated using different deposition processes. We achieved promising power conversion efficiencies of 1.48%. The second part of the thesis demonstrates a novel method for the in situ synthesis and patterning of nanocrystals via reactive inkjet printing. The use of low-cost manufacturing approaches for the synthesis of nanocrystals is critical for many applications, including photonics and electronics. In this work, a simple, low-cost method for the synthesis of nanocrystals with minimum size variation and waste using reactive inkjet printing is introduced. As a proof of concept, the

  19. Towards improved photovoltaic conversion using dilute magnetic semiconductors (abstract only)

    International Nuclear Information System (INIS)

    Olsson, Paer; Guillemoles, J-F; Domain, C

    2008-01-01

    Present photovoltaic devices, based on p/n junctions, are limited from first principles to maximal efficiencies of 31% (40% under full solar concentration; Shockley and Queisser 1961 J. Appl. Phys. 32 510). However, more innovative schemes may overcome the Shockley-Queisser limit since the theoretical maximal efficiency of solar energy conversion is higher than 85% (Harder and Wuerfel 2003 Semicond. Sci. Technol. 18 S151). To date, the only practical realization of such an innovative scheme has been multi-junction devices, which at present hold the world record for efficiency at nearly 41% at significant solar concentration (US DOE news site: http://www.energy.gov/news/4503.htm). It has been proposed that one could make use of the solar spectrum in much the same way as the multi-junction devices do but in a single cell, using impurity induced intermediate levels to create gaps of different sizes. This intermediate level semiconductor (ILSC) concept (Green and Wenham 1994 Appl. Phys. Lett. 65 2907; Luque and MartI1997 Phys. Rev. Lett. 78 5014) has a maximal efficiency similar to that of multi-junction devices but suffers from prohibitively large non-radiative recombination rates. We here propose to use a ferromagnetic impurity scheme in order to reduce the non-radiative recombination rates while maintaining the high theoretical maximum efficiency of the ILSC scheme, that is about 46%. Using density functional theory calculations, the electronic and energetic properties of transition metal impurities for a wide range of semiconductors have been analysed. Of the several hundred compounds studied, only a few fulfil the design criteria that we present here. As an example, wide gap AlP is one of the most promising compounds. It was found that inclusion of significant amounts of Mn in AlP induces band structures providing conversion efficiencies potentially close to the theoretical maximum, with an estimated Curie temperature reaching above 100 K

  20. Charge Saturation and Intrinsic Doping in Electrolyte-Gated Organic Semiconductors.

    Science.gov (United States)

    Atallah, Timothy L; Gustafsson, Martin V; Schmidt, Elliot; Frisbie, C Daniel; Zhu, X-Y

    2015-12-03

    Electrolyte gating enables low voltage operation of organic thin film transistors, but little is known about the nature of the electrolyte/organic interface. Here we apply charge-modulation Fourier transform infrared spectroscopy, in conjunction with electrical measurements, on a model electrolyte gated organic semiconductor interface: single crystal rubrene/ion-gel. We provide spectroscopic signature for free-hole like carriers in the organic semiconductor and unambiguously show the presence of a high density of intrinsic doping of the free holes upon formation of the rubrene/ion-gel interface, without gate bias (Vg = 0 V). We explain this intrinsic doping as resulting from a thermodynamic driving force for the stabilization of free holes in the organic semiconductor by anions in the ion-gel. Spectroscopy also reveals the saturation of free-hole like carrier density at the rubrene/ion-gel interface at Vg < -0.5 V, which is commensurate with the negative transconductance seen in transistor measurements.

  1. Characterizations of Chitosan-Based Polymer Electrolyte Photovoltaic Cells

    International Nuclear Information System (INIS)

    Buraidah, M.H.; Teo, L.P.; Majid, S.R.; Yahya, R.; Taha, R.M.; Arof, A.K.

    2010-01-01

    The membranes 55 wt.% chitosan-45 wt.% NH4I, 33 wt.% chitosan-27 wt.% NH4I-40 wt.% EC, and 27.5 wt.% chitosan-22.5 wt.%?NH4I-50 wt.% buthyl-methyl-imidazolium-iodide (BMII) exhibit conductivity of 3.73 x 10-7, 7.34x10-6, and 3.43x10-5 S cm -1 , respectively, at room temperature. These membranes have been used in the fabrication of solid-state solar cells with configuration ITO/TiO 2 /polymer electrolyte membrane/ITO. It is observed that the short-circuit current density increases with conductivity of the electrolyte. The use of anthocyanin pigment obtained by solvent extraction from black rice and betalain from the callus of Celosia plumosa also helps to increase the short-circuit current.

  2. Synthesis and Characterization of Colloidal Metal and Photovoltaic Semiconductor Nanocrystals

    KAUST Repository

    Abulikemu, Mutalifu

    2014-01-01

    -performing photovoltaic nanocrystals contain toxic elements, such as Pb, or scarce elements, such as In; thus, the production of solution-processable nanocrystals from earth-abundant materials using environmentally benign synthesis and processing methods has become a

  3. Photovoltaic cells and photodetectors made with semiconductor polymers: recent progress

    Science.gov (United States)

    Yu, Gang; Srdanov, Gordana; Wang, Hailiang; Cao, Yong; Heeger, Alan J.

    2000-05-01

    In this presentation, we discuss recent progress on polymer photovoltaic cells and polymer photodetectors. By improving the fill-factor of polymer photovoltaic cells, the energy conversion efficiency was improved significantly to over 4 percent. Such high efficiency polymer photovoltaic cells are promising for many applications including e-papers, e-books and smart-windows. Polymer photodetectors with similar device configuration show high photosensitivity, low dark current, large dynamic range, linear intensity dependence, low noise level and fast response time. These parameters are comparable to or even better than their inorganic counterparts. The advantages of low manufacturing cost, large detection area, and easy hybridization and integration with other electronic or optical components make them promising for a variety of applications including chemical/biomedical analysis, full-color digital image sensing and high energy radiation detection.

  4. Photoelectrical Stimulation of Neuronal Cells by an Organic Semiconductor-Electrolyte Interface.

    Science.gov (United States)

    Abdullaeva, Oliya S; Schulz, Matthias; Balzer, Frank; Parisi, Jürgen; Lützen, Arne; Dedek, Karin; Schiek, Manuela

    2016-08-23

    As a step toward the realization of neuroprosthetics for vision restoration, we follow an electrophysiological patch-clamp approach to study the fundamental photoelectrical stimulation mechanism of neuronal model cells by an organic semiconductor-electrolyte interface. Our photoactive layer consisting of an anilino-squaraine donor blended with a fullerene acceptor is supporting the growth of the neuronal model cell line (N2A cells) without an adhesion layer on it and is not impairing cell viability. The transient photocurrent signal upon illumination from the semiconductor-electrolyte layer is able to trigger a passive response of the neuronal cells under physiological conditions via a capacitive coupling mechanism. We study the dynamics of the capacitive transmembrane currents by patch-clamp recordings and compare them to the dynamics of the photocurrent signal and its spectral responsivity. Furthermore, we characterize the morphology of the semiconductor-electrolyte interface by atomic force microscopy and study the stability of the interface in dark and under illuminated conditions.

  5. Semiconductor Grade, Solar Silicon Purification Project. [photovoltaic solar energy conversion

    Science.gov (United States)

    Ingle, W. M.; Rosler, R. S.; Thompson, S. W.; Chaney, R. E.

    1979-01-01

    A low cost by-product, SiF4, is reacted with mg silicon to form SiF2 gas which is polymerized. The (SiF2)x polymer is heated forming volatile SixFy homologues which disproportionate on a silicon particle bed forming silicon and SiF4. The silicon analysis procedure relied heavily on mass spectroscopic and emission spectroscopic analysis. These analyses demonstrated that major purification had occured and some samples were indistinguishable from semiconductor grade silicon (except possibly for phosphorus). However, electrical analysis via crystal growth reveal that the product contains compensated phosphorus and boron.

  6. Near-thermal limit gating in heavily doped III-V semiconductor nanowires using polymer electrolytes

    Science.gov (United States)

    Ullah, A. R.; Carrad, D. J.; Krogstrup, P.; Nygârd, J.; Micolich, A. P.

    2018-02-01

    Doping is a common route to reducing nanowire transistor on-resistance but it has limits. A high doping level gives significant loss in gate performance and ultimately complete gate failure. We show that electrolyte gating remains effective even when the Be doping in our GaAs nanowires is so high that traditional metal-oxide gates fail. In this regime we obtain a combination of subthreshold swing and contact resistance that surpasses the best existing p -type nanowire metal-oxide semiconductor field-effect transistors (MOSFETs). Our subthreshold swing of 75 mV/dec is within 25 % of the room-temperature thermal limit and comparable with n -InP and n -GaAs nanowire MOSFETs. Our results open a new path to extending the performance and application of nanowire transistors, and motivate further work on improved solid electrolytes for nanoscale device applications.

  7. Theory of photovoltaic characteristics of semiconductor quantum dot solar cells

    International Nuclear Information System (INIS)

    Wu, Yuchang; Asryan, Levon V.

    2016-01-01

    We develop a comprehensive rate equations model for semiconductor quantum dot solar cells (QDSCs). The model is based on the continuity equations with a proper account for quantum dots (QDs). A general analytical expression for the total current density is obtained, and the current-voltage characteristic is studied for several specific situations. The degradation in the open circuit voltage of the QDSC is shown to be due to strong spontaneous radiative recombination in QDs. Due to small absorption coefficient of the QD ensemble, the improvement in the short circuit current density is negligible if only one QD layer is used. If spontaneous radiative recombination would be suppressed in QDs, a QDSC with multiple QD layers would have significantly higher short circuit current density and power conversion efficiency than its conventional counterpart. The effects of photoexcitation of carriers from discrete-energy states in QDs to continuum-energy states are discussed. An extended model, which includes excited states in QDs, is also introduced.

  8. Polycrystalline silicon availability for photovoltaic and semiconductor industries

    Science.gov (United States)

    Ferber, R. R.; Costogue, E. N.; Pellin, R.

    1982-01-01

    Markets, applications, and production techniques for Siemens process-produced polycrystalline silicon are surveyed. It is noted that as of 1982 a total of six Si materials suppliers were servicing a worldwide total of over 1000 manufacturers of Si-based devices. Besides solar cells, the Si wafers are employed for thyristors, rectifiers, bipolar power transistors, and discrete components for control systems. An estimated 3890 metric tons of semiconductor-grade polycrystalline Si will be used in 1982, and 6200 metric tons by 1985. Although the amount is expected to nearly triple between 1982-89, research is being carried out on the formation of thin films and ribbons for solar cells, thereby eliminating the waste produced in slicing Czolchralski-grown crystals. The free-world Si production in 1982 is estimated to be 3050 metric tons. Various new technologies for the formation of polycrystalline Si at lower costs and with less waste are considered. New entries into the industrial Si formation field are projected to produce a 2000 metric ton excess by 1988.

  9. Theory of photovoltaic characteristics of semiconductor quantum dot solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yuchang, E-mail: yuchangw@cumt.edu.cn [Low Carbon Energy Institute, China University of Mining and Technology, Xuzhou 221116 (China); School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116 (China); Asryan, Levon V., E-mail: asryan@vt.edu [Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States)

    2016-08-28

    We develop a comprehensive rate equations model for semiconductor quantum dot solar cells (QDSCs). The model is based on the continuity equations with a proper account for quantum dots (QDs). A general analytical expression for the total current density is obtained, and the current-voltage characteristic is studied for several specific situations. The degradation in the open circuit voltage of the QDSC is shown to be due to strong spontaneous radiative recombination in QDs. Due to small absorption coefficient of the QD ensemble, the improvement in the short circuit current density is negligible if only one QD layer is used. If spontaneous radiative recombination would be suppressed in QDs, a QDSC with multiple QD layers would have significantly higher short circuit current density and power conversion efficiency than its conventional counterpart. The effects of photoexcitation of carriers from discrete-energy states in QDs to continuum-energy states are discussed. An extended model, which includes excited states in QDs, is also introduced.

  10. Electrolytic charge inversion at the liquid-solid interface in a nanopore in a doped semiconductor membrane

    Energy Technology Data Exchange (ETDEWEB)

    Gracheva, Maria E [Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Leburton, Jean-Pierre [Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

    2007-04-11

    The electrostatics of a nanopore in a doped semiconductor membrane immersed in an electrolyte is studied with a numerical model. Unlike dielectric membranes that always attract excess positive ion charges at the electrolyte/membrane interface whenever a negative surface charge is present, semiconductor membranes exhibit more versatility in controlling the double layer at the membrane surface. The presence of dopant charge in the semiconductor membrane, the shape of the nanopore and the negative surface charge resulting from the pore fabrication process have competing influences on the double layer formation. The inversion of the electrolyte surface charge from negative to positive is observed for n-Si membranes as a function of the membrane surface charge density, while no such inversion occurs for dielectric and p-Si membranes.

  11. New Organic Semiconductor Materials Applied in Organic Photovoltaic and Optical Devices

    Directory of Open Access Journals (Sweden)

    Andre F. S. Guedes

    2015-04-01

    Full Text Available The development of flexible organic photovoltaic solar cells, using an optically transparent substrate material and organic semiconductor materials, has been widely utilized by the electronic industry when producing new technological products. The flexible organic photovoltaic solar cells are the base Poly (3,4-ethylenedioxythiophene, PEDOT, Poly(3-hexyl thiophene, P3HT, Phenyl-C61-butyric acid methyl ester, PCBM and Polyaniline, PANI, were deposited in Indium Tin Oxide, ITO, and characterized by Electrical Measurements and Scanning Electron Microscopy (SEM. In addition, the thin film obtained by the deposition of PANI, prepared in perchloric acid solution, was identified through PANI-X1. The result obtained by electrical Measurements has demonstrated that the PET/ITO/PEDOT/P3HT:PCBM Blend/PANI-X1 layer presents the characteristic curve of standard solar cell after spin-coating and electrodeposition. The Thin film obtained by electrodeposition of PANI-X1 on P3HT/PCBM Blend was prepared in perchloric acid solution. These flexible organic photovoltaic solar cells presented power conversion efficiency of 12%. The inclusion of the PANI-X1 layer reduced the effects of degradation these organic photovoltaic panels induced for solar irradiation. In Scanning Electron Microscopy (SEM these studies reveal that the surface of PANI-X1 layers is strongly conditioned by the surface morphology of the dielectric.

  12. Development and Electrochemical Investigations of an EIS- (Electrolyte-Insulator-Semiconductor based Biosensor for Cyanide Detection

    Directory of Open Access Journals (Sweden)

    Michael J. Schöning

    2007-08-01

    Full Text Available A cyanide biosensor based on a pH-sensitive p-doped electrolyte-insulator-semiconductor (EIS structure with an immobilised enzyme (cyanidase is realised at thelaboratory scale. The immobilisation of the cyanidase is performed in two distinct steps:first, the covalent coupling of cyanidase to an N-hydroxysuccinimide- (NHS activatedSepharoseTM gel and then, the physical entrapment of NHS-activated SepharoseTM with theimmobilised cyanidase in a dialysis membrane onto the EIS structure. The immobilisationof the cyanidase to the NHS-activated SepharoseTM is studied by means of gelelectrophoresis measurements and investigations using an ammonia- (NH3 selectiveelectrode. For the electrochemical characterisation of the cyanide biosensor,capacitance/voltage and constant capacitance measurements, respectively, have beencarried out. A differential measurement procedure is presented to evaluate the cyanideconcentration-dependent biosensor signals.

  13. Study of Surface States at the Semiconductor/electrolyte Interface of Liquid-Junction Solar Cells.

    Science.gov (United States)

    Siripala, Withana P.

    The existence of surface states at the semiconductor electrolyte interface of photoelectrochemical (PEC) cells plays a major role in determining the performance of the device in regard to the potential distribution and transport mechanisms of photogenerated carriers at the interface. We have investigated the n-TiO(,2)/electrolyte interface using three experimental techniques: relaxation spectrum analysis, photocurrent spectroscopy, and electrolyte electroreflectance (EER) spectroscopy. The effect of Fermi level pinning at the CdIn(,2)SE(,4)/aqueous-polysulfide interface was also studied using EER. Three distinct surface states were observed at the n-TiO(,2)/aqueous-electrolyte interface. The dominant state, which tails from the conduction band edge, is primarily responsible for the surface recombination of photocarriers at the interface. The second surface state, observed at 0.8 eV below the conduction band of TiO(,2), originates in the dark charge transfer intermediates (TiO(,2)-H). It is proposed that the sub-bandgap (SBG) photocurrent-potential behavior is a result of the mechanism of dynamic formation and annihilation of these surface states. The third surface state was at 1.3 eV below the conduction band of TiO(,2), and the SBG EER measurements show this state is "intrinsic" to the surface. These states were detected with SBG EER and impedance measurements in the presence of electrolytes that can adsorb on the surface of TiO(,2). Surface concentration of these states was evaluated with impedance measurements. EER measurements on a CdIn(,2)Se(,4)/polysulfide system have shown that the EER spectrum is sensitive to the surface preparation of the sample. The EER signal was quenched as the surface was driven to strong depletion, owing to Fermi level pinning at the interface in the presence of a high density of surface states. The full analysis of this effect enables us to measure the change in the flatband potential, as a function of the electrode potential, and

  14. Influence of polyoxyethylene phytosterol addition in ionic liquid-based electrolyte on photovoltaic performance of dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Takahashi, Masashi; Sato, Kei; Sakurai, Sho; Kobayashi, Koichi

    2016-01-01

    Highlights: • The ionic liquid solution of less solvophilic BPS exhibits a better surface active property and a weaker dye-desorption effect. • Photovoltaic performances of the N719- and NKX2677-sensitized DSSCs can be improved by the BPS addition to the IL-based electrolyte. • BPS added to the electrolyte plays a key role in reducing charge-transfer resistance and increasing electron lifetime in the TiO 2 electrode. - Abstract: In this work, we studied influence of polyoxyethylene phytosterol (BPS) addition in ionic liquid (IL)-based electrolyte on photovoltaic performance of dye-sensitized solar cells (DSSCs) using 1-methyl-3-propylimidazolium iodide as an IL. Surface tension, photocurrent density-voltage characteristics and electrochemical impedance spectra were measured to clarify the role of BPS in the DSSCs using three different dyes. The results showed that the IL solution of less solvophilic BPS-EO5 exhibited a better surface active property and a weaker dye-desorption effect than BPS-EO30 and BPS-PO7/EO30. Short-circuit current densities of the N719- and NKX2677-sensitized cells were found to be noticeably increased by the addition of either BPS-EO5 or BPS-EO30 to the IL-based electrolyte in the concentration range of 0.001–0.01 mol dm −3 . Enhanced photovoltaic conversion efficiencies were obtained for these DSSCs, which most likely resulted from the effects of BPS on reducing charge-transfer resistance at the TiO 2 /dye/electrolyte interface and on increasing electron lifetime within the TiO 2 photoanode.

  15. Seawater operating bio-photovoltaic cells coupling semiconductor photoanodes and enzymatic biocathodes

    DEFF Research Database (Denmark)

    Zhang, Lingling; Alvarez-Martos, Isabel; Vakurov, Alexander

    2017-01-01

    and inexpensive way. Here, we report clean and sustainable conversion of solar energy into electricity by photo-and bio-electrocatalytic recycling of the H2O/O-2 redox couple in a hybrid bio-photovoltaic (BPV) membraneless cell comprising a sunlight-illuminated water-oxidizing semiconductor anode (either Zn......-doped hematite or TiO2) and an oxygen-reducing enzymatic biocathode, in such environmental media as seawater. Upon simulated solar light illumination (AM 1.5G, 100 mW cm(-2)), the maximum power density (P-max) generated by the cell was 236 and 21.4 mu W cm(-2) in 1 M Tris-HCl and seawater, both at pH 8...... thermodynamically feasible coupling of cost-effective photoactive materials such as TiO2 or hematite semiconductors and enzymatic counterparts in seawater media opens a prospective clean and sustainable way of transformation of the most abundant, clean and renewable source of energy - solar light - and the Earth...

  16. Critical role of the semiconductor-electrolyte interface in photocatalytic performance for water-splitting reactions using Ta3N5 particles

    KAUST Repository

    Nurlaela, Ela; Ould-Chikh, Samy; Harb, Moussab; Del Gobbo, Silvano; Aouine, Mimoun; Puzenat, Eric; Sautet, Philippe; Domen, Kazunari; Basset, Jean-Marie; Takanabe, Kazuhiro

    2014-01-01

    the experiments. Electrochemical and Mott-Schottky analyses demonstrated that the surface layer drastically affects the energetic picture at the semiconductor-electrolyte interface, which can consequently affect the photocatalytic performance. Chemical etching

  17. Density Functional Theory Simulations of Semiconductors for Photovoltaic Applications: Hybrid Organic-Inorganic Perovskites and III/V Heterostructures

    Directory of Open Access Journals (Sweden)

    Jacky Even

    2014-01-01

    Full Text Available Potentialities of density functional theory (DFT based methodologies are explored for photovoltaic materials through the modeling of the structural and optoelectronic properties of semiconductor hybrid organic-inorganic perovskites and GaAs/GaP heterostructures. They show how the properties of these bulk materials, as well as atomistic relaxations, interfaces, and electronic band-lineups in small heterostructures, can be thoroughly investigated. Some limitations of available standard DFT codes are discussed. Recent improvements able to treat many-body effects or based on density-functional perturbation theory are also reviewed in the context of issues relevant to photovoltaic technologies.

  18. Effect of electrolytes on the photovoltaic performance of a hybrid dye sensitized ZnO solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Suri, Poonam; Mehra, R.M. [Department of Electronic Science, University of Delhi South Campus, New Delhi 110021 (India)

    2007-03-23

    The efficiency of dye sensitized solar cell depends on the number of factors such as impedance due to anions in the electrolytes, oxidation-reduction process of anions and size of cations of the electrolyte. This paper reports the effect of electrolytes on the photovoltaic performance of hybrid dye sensitized ZnO solar cells based on Eosin Y dye. The size of the cations has been varied by choosing different electrolytes such as LiBr+Br{sub 2}, LiI+I{sub 2}, tetrapropylammonium iodide +I{sub 2} in mixed solvent of acetronitrile and ethylene carbonate. The impedance of anions has been determined by electrochemical impedance spectra. It is observed that Br{sup -}/Br{sub 3}{sup -} offers high impedance as compared to I{sup -}/I{sub 3}{sup -} couple. The oxidation-reduction reactions of electrolytes are measured by linear sweep voltammogram. It is found that Br{sup -}/Br{sub 3}{sup -} is more suitable than an I{sup -}/I{sub 3}{sup -} couple in dye sensitized solar cell (DSSC) in terms of higher open-circuit photovoltage production and higher overall energy conversion efficiency. This is attributed to more positive potential of the dye sensitizer than that of Br{sup -}/Br{sub 3}{sup -}. The gain in V{sub oc} was due to the enlarged energy level difference between the redox potential of the electrolyte and the Fermi level (E{sub f}) of ZnO and the suppressed charge recombination as well. (author)

  19. A Novel Semiconductor CIGS Photovoltaic Material and Thin-Film ED Technology

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to achieve low-cost high-efficiency thin-film solar cells, a novel Semiconductor Photovoltaic (PV) active material CuIn1-xGaxSe2 (CIGS) and thin-film Electro-Deposition (ED) technology is explored. Firstly,the PV materials and technologies is investigated, then the detailed experimental processes of CIGS/Mo/glass structure by using the novel ED technology and the results are reported. These results shows that high quality CIGS polycrystalline thin-films can be obtained by the ED method, in which the polycrystalline CIGS is definitely identified by the (112), (204, 220) characteristic peaks of the tetragonal structure, the continuous CIGS thin-film layers with particle average size of about 2μm of length and around 1.6μm of thickness. The thickness and solargrade quality of CIGS thin-films can be produced with good repeatability. Discussion and analysis on the ED technique, CIGS energy band and sodium (Na) impurity properties, were also performed. The alloy CIGS exhibits not only increasing band-gap with increasing x, but also a change in material properties that is relevant to the device operation. The beneficial impurity Na originating from the low-cost soda-lime glass substrate becomes one prerequisite for high quality CIGS films. These novel material and technology are very useful for low-cost high-efficiency thin-film solar cells and other devices.

  20. Semiconductor

    International Nuclear Information System (INIS)

    2000-01-01

    This book deals with process and measurement of semiconductor. It contains 20 chapters, which goes as follows; semiconductor industry, introduction of semiconductor manufacturing, yield of semiconductor process, materials, crystal growth and a wafer forming, PN, control pollution, oxidation, photomasking photoresist chemistry, photomasking technologies, diffusion and ion injection, chemical vapor deposition, metallization, wafer test and way of evaluation, semiconductor elements, integrated circuit and semiconductor circuit technology.

  1. Manufacture and demonstration of organic photovoltaic-powered electrochromic displays using roll coating methods and printable electrolytes

    DEFF Research Database (Denmark)

    Jensen, Jacob; Dam, Henrik Friis; Reynolds, John R.

    2012-01-01

    active material (ECP-Magenta) and poly(N-octadecyl-(propylene-1,3-dioxy)-3,4-pyrrole-2,5-diyl) as a minimally colored, charge balancing material (MCCP). Two electrolyte systems were compared to allow development of fully printable and laminated devices on flexible substrates. Devices of various sizes, up...... to 7 × 8 cm2, are demonstrated with pixelated devices containing pixel sizes of 4 × 4 mm2 or 13 × 13 mm2. The transmission contrast exhibited by the devices, when switched between the fully bleached and fully colored state, was 58% at a visible wavelength of 550 nm, and the devices exhibited switching...... times of photovoltaic devices (with or without the use of a lithium-polymer battery) to power the devices between the colored and bleached state, illustrating a self-powered ECD. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B...

  2. Predicting suitable optoelectronic properties of monoclinic VON semiconductor crystals for photovoltaics using accurate first-principles computations

    KAUST Repository

    Harb, Moussab

    2015-01-01

    Using accurate first-principles quantum calculations based on DFT (including the perturbation theory DFPT) with the range-separated hybrid HSE06 exchange-correlation functional, we predict essential fundamental properties (such as bandgap, optical absorption coefficient, dielectric constant, charge carrier effective masses and exciton binding energy) of two stable monoclinic vanadium oxynitride (VON) semiconductor crystals for solar energy conversion applications. In addition to the predicted band gaps in the optimal range for making single-junction solar cells, both polymorphs exhibit relatively high absorption efficiencies in the visible range, high dielectric constants, high charge carrier mobilities and much lower exciton binding energies than the thermal energy at room temperature. Moreover, their optical absorption, dielectric and exciton dissociation properties are found to be better than those obtained for semiconductors frequently utilized in photovoltaic devices like Si, CdTe and GaAs. These novel results offer a great opportunity for this stoichiometric VON material to be properly synthesized and considered as a new good candidate for photovoltaic applications.

  3. Predicting suitable optoelectronic properties of monoclinic VON semiconductor crystals for photovoltaics using accurate first-principles computations

    KAUST Repository

    Harb, Moussab

    2015-08-26

    Using accurate first-principles quantum calculations based on DFT (including the perturbation theory DFPT) with the range-separated hybrid HSE06 exchange-correlation functional, we predict essential fundamental properties (such as bandgap, optical absorption coefficient, dielectric constant, charge carrier effective masses and exciton binding energy) of two stable monoclinic vanadium oxynitride (VON) semiconductor crystals for solar energy conversion applications. In addition to the predicted band gaps in the optimal range for making single-junction solar cells, both polymorphs exhibit relatively high absorption efficiencies in the visible range, high dielectric constants, high charge carrier mobilities and much lower exciton binding energies than the thermal energy at room temperature. Moreover, their optical absorption, dielectric and exciton dissociation properties are found to be better than those obtained for semiconductors frequently utilized in photovoltaic devices like Si, CdTe and GaAs. These novel results offer a great opportunity for this stoichiometric VON material to be properly synthesized and considered as a new good candidate for photovoltaic applications.

  4. Photoelectrical stimulation of neuronal cells by an organic semiconductor-electrolyte Interface

    DEFF Research Database (Denmark)

    Abdullaeva, Oliya S.; Schulz, Matthias; Balzer, Frank

    2016-01-01

    As a step toward the realization of neuroprosthetics for vision restoration, we follow an electrophysiological patch-clamp approach to study the fundamental photoelectrical stimulation mechanism of neuronal model cells by an organic semiconductor–electrolyte interface. Our photoactive layer...... consisting of an anilino-squaraine donor blended with a fullerene acceptor is supporting the growth of the neuronal model cell line (N2A cells) without an adhesion layer on it and is not impairing cell viability. The transient photocurrent signal upon illumination from the semiconductor–electrolyte layer....... Furthermore, we characterize the morphology of the semiconductor–electrolyte interface by atomic force microscopy and study the stability of the interface in dark and under illuminated conditions....

  5. Polyaniline–titania solid electrolyte for new generation photovoltaic single-layer devices

    International Nuclear Information System (INIS)

    Ibrahim, Michael; Bassil, Maria; Demirci, Umit B.; Khoury, Tony; El Haj Moussa, Georges; El Tahchi, Mario; Miele, Philippe

    2012-01-01

    Highlights: ► Strong interaction between polyaniline and TiO 2 and the formation of a core/shell structure. ► Enhancement of the absorption of TiO 2 in the visible range. ► Diode-like behavior with low polyaniline content. ► Single layer photovoltaic device based on solid polyaniline–TiO 2 composite. - Abstract: In this study, in situ chemical oxidative polymerization of very low quantities of aniline doped with HCl using ammonium persulfate inside an aqueous solution of 10 wt.% of titanium dioxide was used to prepare a novel photovoltaic paint. Photoelectrical properties of the composite have been observed and the operating principle of the photovoltaic device is presented. We report an enhancement of the absorption of TiO 2 powder in the visible range due to the sensitization by conductive polyaniline. Under illumination an open circuit voltage of 593 mV and a short circuit current density of 0.502 A m −2 were recorded. The surface conductivity of PANI–TiO 2 pellets is measured using the four-point probe technique. The percolation theory together with variable range hopping explained the behavior of the surface conductivity of the composites. Morphological analysis using Transmission Electron Microscope showed the core/shell structure of the composites and energy dispersive X-ray showed the homogeneity of the composite. Fourier transform infrared spectroscopy confirmed the chemical adsorption of polyaniline at the surface of TiO 2 . UV–visible spectroscopy showed a shift of the polaron energy inside the polyaniline energy gap. The proposed morphology is showed to be responsible for the photoactivity of the composite.

  6. Photovoltaics

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the photovoltaics. It presents the principles and the applications, the issues and the current technology, the challenges and the Group Total commitment in the domain. (A.L.B.)

  7. The Effect of Metal-Semiconductor Contact on the Transient Photovoltaic Characteristic of HgCdTe PV Detector

    Directory of Open Access Journals (Sweden)

    Haoyang Cui

    2013-01-01

    Full Text Available The transient photovoltaic (PV characteristic of HgCdTe PV array is studied using an ultrafast laser. The photoresponse shows an apparent negative valley first, then it evolves into a positive peak. By employing a combined theoretical model of pn junction and Schottky potential, this photo-response polarity changing curves can be interpreted well. An obvious decreasing of ratio of negative valley to positive peak can be realized by limiting the illumination area of the array electrode. This shows that the photoelectric effect of Schottky barrier at metal-semiconductor (M/S interface is suppressed, which will verify the correctness of the model. The characteristic parameters of transient photo-response induced from p-n junction and Schottky potential are extracted by fitting the response curve utilizing this model. It shows that the negative PV response induced by the Schottky barrier decreases the positive photovoltage generated by the pn junction.

  8. Optoelectronic and Photovoltaic Properties of the Air-Stable Organohalide Semiconductor (CH 3 NH 3 ) 3 Bi 2 I 9

    KAUST Repository

    Abulikemu, Mutalifu

    2016-07-14

    Lead halide perovskite materials have shown excellent optoelectronic as well as photovoltaic properties. However, the presence of lead and the chemical instability relegate lead halide perovskites to research applications only. Here, we investigate an emerging lead-free and air stable compound (CH3NH3)3Bi2I9 as a non-toxic potential alternative to lead halide perovskites. We have synthesized thin films, powders and millimeter-scale single crystals of (CH3NH3)3Bi2I9 and investigated their structural and optoelectronic properties. We demonstrate that the degree of crystallinity strongly affects the optoelectronic properties of the material, resulting in significantly different band gaps in polycrystalline thin films and single crystals. Surface photovoltage spectroscopy reveals outstanding photocharge generation in the visible (<700 nm), while transient absorption spectroscopy and space charge limited current measurements point to a long exciton lifetime and a high carrier mobility, respectively, similar to lead halide perovskites, pointing to the remarkable potential of this semiconductor. Photovoltaic devices fabricated using this material yield low power conversion efficiency (PCE) to date, but the PCE is expected to rise with improvements in thin film processing and device engineering.

  9. Photovoltaic semiconductor materials based on alloys of tin sulfide, and methods of production

    Science.gov (United States)

    Lany, Stephan

    2016-06-07

    Photovoltaic thin-film materials comprising crystalline tin sulfide alloys of the general formula Sn.sub.1-x(R).sub.xS, where R is selected from magnesium, calcium and strontium, as well as methods of producing the same, are disclosed.

  10. High-Throughput Computational Assessment of Previously Synthesized Semiconductors for Photovoltaic and Photoelectrochemical Devices

    DEFF Research Database (Denmark)

    Kuhar, Korina; Pandey, Mohnish; Thygesen, Kristian Sommer

    2018-01-01

    Using computational screening we identify materials with potential use as light absorbers in photovoltaic or photoelectrochemical devices. The screening focuses on compounds of up to three different chemical elements which are abundant and nontoxic. A prescreening is carried out based on informat...

  11. Enhanced photovoltaic performance and long-term stability of dye-sensitized solar cells by incorporating SiO{sub 2} nanoparticles in binary ionic liquid electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hsin-Fang; Wu, Jhih-Lin; Hsu, Po-Ya [Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC (China); Tung, Yung-Liang [Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu 30013, Taiwan, ROC (China); Ouyang, Fan-Yi [Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC (China); Kai, Ji-Jung, E-mail: jjkai@ess.nthu.edu.tw [Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC (China)

    2013-02-01

    Hydrophilic SiO{sub 2} nanoparticles in a binary ionic liquid (bi-IL) consisting of 1-propyl-3-methylimidazolium iodide (PMII) and 1-ethyl-3-methyl-imidazolium dicyanimide (EMIDCA) facilitated electron transfer and solidified the electrolyte for a dye-sensitized solar cell (DSC). We investigated the dependence of charge transport and photovoltaic performance on the composition of bi-IL electrolytes with varied ratio of SiO{sub 2} nanoparticles. The electrochemical impedance spectra revealed a decreased resistance to charge transfer at the Pt counter electrode (R{sub ct1}) when SiO{sub 2} (up to 2.0 wt.%) was added, improving the photovoltaic parameters. The DSC based on a TiO{sub 2} nanocrystalline film (thickness 14.2 μm) with a composite ionic gel electrolyte of EMIDCA/PMII bi-IL (33 vol.% of EMIDCA) incorporating SiO{sub 2} (2 wt.%) exhibited a power conversion efficiency of 5.28% under simulated solar illumination (AM 1.5 G, 100 mW cm{sup −} {sup 2}). The durability of DSC with a SiO{sub 2} solidified electrolyte was superior to that of a liquid one, exhibiting good stability at 60 °C in darkness during an accelerated test for 1000 h. - Highlights: ► SiO{sub 2} nanoparticles were introduced in a binary ionic liquid electrolyte. ► Effect of various ratios of SiO{sub 2} nanoparticles in gel electrolytes was studied. ► Mechanism of charge transfer with addition of SiO{sub 2} nanoparticles was discussed. ► An enhanced solar to electric energy conversion efficiency of 5.28% was achieved. ► Thermal stability of a quasi-solid state dye-sensitized solar cell was improved.

  12. ZnTe Semiconductor-Polymer Gel Composited Electrolyte for Conversion of Solar Energy

    Directory of Open Access Journals (Sweden)

    Wonchai Promnopas

    2014-01-01

    Full Text Available Nanostructured cubic p-type ZnTe for dye sensitized solar cells (DSSCs was synthesized from 1 : 1 molar ratio of Zn : Te by 600 W and 900 W microwave plasma for 30 min. In this research, their green emissions were detected at the same wavelengths of 563 nm, the energy gap (Eg at 2.24 eV, and three Raman shifts at 205, 410, and 620 cm−1. The nanocomposited electrolyte of quasisolid state ZnO-DSSCs was in correlation with the increase in the JSC, VOC, fill factor (ff, and efficiency (η by increasing the wt% of ZnTe-GPE (gel polymer electrolyte to an optimum value and decreased afterwards. The optimal ZnO-DSSC performance was achieved for 0.20 wt% ZnTe-GPE with the highest photoelectronic energy conversion efficiency at 174.7% with respect to that of the GPE without doping of p-type ZnTe.

  13. Photovoltaic performance of bifacial dye sensitized solar cell using chemically healed binary ionic liquid electrolyte solidified with SiO2 nanoparticles

    International Nuclear Information System (INIS)

    Cosar, Burak; Icli, Kerem Cagatay; Yavuz, Halil Ibrahim; Ozenbas, Macit

    2013-01-01

    Highlights: ► A bifacial DSSC is realized and irradiated from front and rear sides. ► Maximum efficiency was found for 70% PMII/30% (EMIB(CN) 4 ) electrolyte composition. ► A significant increase in photocurrent using 0.1 M GuSCN and 0.4 M NMB was observed. ► Addition of SiO 2 nanoparticles to the electrolyte enhanced photovoltaic efficiency. ► Dispersed SiO 2 particles are found to be more efficient compared to SiO 2 overlayer. - Abstract: In this study, we investigated the effect of electrolyte composition, photoanode thickness, and the additions of GuSCN (guanidinium thiocyanate), NMB (N-methylbenimidazole), and SiO 2 on the photovoltaic performance of DSSCs (dye sensitized solar cells). A bifacial DSSC is realized and irradiated from front and rear sides. The devices give maximum photovoltaic efficiencies for 70% PMII (1-propyl-3-methyl-imidazolium iodide)/30% (EMIB(CN) 4 ) (1-ethyl-3-methyl-imidazolium tetracyanoborate) electrolyte composition and 10 μm thick photoanode coating which is considered to be the ideal coating thickness for the diffusion length of electrolyte and dye absorption. A significant increase in the photocurrent for DSSCs with optimum molarity of 0.1 M GuSCN was observed due to decreased recombination which is believed to be surface passivation effect at photoanode electrolyte interface suppressing recombination rate. Moreover, optimum NMB molarity was found to be 0.4 for maximum efficiency. Addition of SiO 2 to the electrolyte both as an overlayer and dispersed particles enhanced rear side illuminated cells where dispersed particles are found to be more efficient for the front side illuminated cells due to additional electron transport properties. Best rear side illuminated cell efficiency was 3.2% compared to front side illuminated cell efficiency of 4.2% which is a promising result for future rear side dye sensitized solar cell applications where front side illumination is not possible like tandem structures and for cells

  14. Improved semiconductors for photovoltaic solar cells. Quarterly report No. 1, July 1-September 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    The purpose of the work on this contract is to study the suitability of Zn/sub 3/P/sub 2/ as a photovoltaic material for large scale terrestrial use. Zn/sub 3/P/sub 2/ was chosen for study because those of its physical parameters which could be gleaned from a rather sparse literature match fairly well the criteria for optimum terrestrial photovoltaic materials. The main emphasis in the quarter has been on material preparation. Materials synthesis has been successful, with a fair number of useable single crystals produced with the bulk material. In addition, thin films have been produced in a preliminary way on various substrates. Initial electrical and optical studies have been carried out in both single crystals and films, but the results of these studies are of a preliminary nature only.

  15. Efficient and Stable Photovoltaic Characteristics of Quasi-Solid State DSSC using Polymer Gel Electrolyte Based on Ionic Liquid in Organosiloxane Polymer Gels

    Science.gov (United States)

    Pujiarti, H.; Arsyad, W. S.; Shobih; Muliani, L.; Hidayat, R.

    2018-04-01

    Dye-Sensitized Solar Cell (DSSC) is still one of the promising solar cell types among the third generation of solar cells because of easiness of fabrication and variety of available materials. In this type of solar cell, the electrolyte is one of the important components for regenerating excited dyes and transporting electric charge carriers to the counter electrode. Indeed, the power conversion efficiency of DSSC can be then significantly affected by the chemical and physical properties of the electrolyte. The simplest electrolyte system of an I-/I3 - redox couple in an organic solvent, however, has some drawbacks due to corrosive properties, volatile and leakage problem. Use of solid phase or gel phase electrolyte may overcome those problems, but it is often considered to suppress the efficiency due to low ion diffusion. Here, we report the photovoltaic characteristics of DSSC using polymer gel electrolyte (PGE), which is composed of ionic liquid and an organosiloxane polymer gel. The better cell performance with power conversion efficiency of about 6% has been obtained by optimizing the mesoporous size of the TiO2 layer and the PGE viscosity.

  16. Photovoltaics

    International Nuclear Information System (INIS)

    Prince, M.B.

    1994-01-01

    Photovoltaic energy systems have the long range potential for supplying a significant part of the world's need for electricity Even today, such systems offer many benefits compared to other energy systems such as fossil fuel, nuclear and other renewable systems. These include: stability, reliability, require no water, no moving parts, environmentally benign, moderate efficiency, modular, universally usable, easy maintenance, and low power distribution costs. This paper will present information on present costs of the key system components, realistic cost projections and the results of a comparative study of three renewable approaches for a large system. (author), (tabs. 2)

  17. Method for making photovoltaic devices using oxygenated semiconductor thin film layers

    Science.gov (United States)

    Johnson, James Neil; Albin, David Scott; Feldman-Peabody, Scott; Pavol, Mark Jeffrey; Gossman, Robert Dwayne

    2014-12-16

    A method for making a photovoltaic device is presented. The method includes steps of disposing a window layer on a substrate and disposing an absorber layer on the window layer. Disposing the window layer, the absorber layer, or both layers includes introducing a source material into a deposition zone, wherein the source material comprises oxygen and a constituent of the window layer, of the absorber layer or of both layers. The method further includes step of depositing a film that comprises the constituent and oxygen.

  18. Photovoltaic

    International Nuclear Information System (INIS)

    Fechner, H.; Heidenreich, M.

    2001-01-01

    In 1993 a wide test for photovoltaic (PV) was carried out in Austria, 110 stations were built and precise measurements were done. At that time the demand of integrating direct current from solar cells into the 50 Hz alternating current network was a weak point. At present four european research projects dealing with security, reliability, network compatibility and its integration in buildings are being developed. The cost development of PVs in Germany from 1983 to 1998 is given. Because of the PV environmental quality, one million of new intallations are demanded (until 2010) by the European commission. In Austria exists ∼5,000 kWp installed capacity and the growth rate average in the last years was 30 %. (nevyjel)

  19. Hot electron dynamics at semiconductor surfaces: Implications for quantum dot photovoltaics

    Science.gov (United States)

    Tisdale, William A., III

    Finding a viable supply of clean, renewable energy is one of the most daunting challenges facing the world today. Solar cells have had limited impact in meeting this challenge because of their high cost and low power conversion efficiencies. Semiconductor nanocrystals, or quantum dots, are promising materials for use in novel solar cells because they can be processed with potentially inexpensive solution-based techniques and because they are predicted to have novel optoelectronic properties that could enable the realization of ultra-efficient solar power converters. However, there is a lack of fundamental understanding regarding the behavior of highly-excited, or "hot," charge carriers near quantum-dot and semiconductor interfaces, which is of paramount importance to the rational design of high-efficiency devices. The elucidation of these ultrafast hot electron dynamics is the central aim of this Dissertation. I present a theoretical framework for treating the electronic interactions between quantum dots and bulk semiconductor surfaces and propose a novel experimental technique, time-resolved surface second harmonic generation (TR-SHG), for probing these interactions. I then describe a series of experimental investigations into hot electron dynamics in specific quantum-dot/semiconductor systems. A two-photon photoelectron spectroscopy (2PPE) study of the technologically-relevant ZnO(1010) surface reveals ultrafast (sub-30fs) cooling of hot electrons in the bulk conduction band, which is due to strong electron-phonon coupling in this highly polar material. The presence of a continuum of defect states near the conduction band edge results in Fermi-level pinning and upward (n-type) band-bending at the (1010) surface and provides an alternate route for electronic relaxation. In monolayer films of colloidal PbSe quantum dots, chemical treatment with either hydrazine or 1,2-ethanedithiol results in strong and tunable electronic coupling between neighboring quantum dots

  20. Magnetic state dependent transient lateral photovoltaic effect in patterned ferromagnetic metal-oxide-semiconductor films

    Directory of Open Access Journals (Sweden)

    Isidoro Martinez

    2015-11-01

    Full Text Available We investigate the influence of an external magnetic field on the magnitude and dephasing of the transient lateral photovoltaic effect (T-LPE in lithographically patterned Co lines of widths of a few microns grown over naturally passivated p-type Si(100. The T-LPE peak-to-peak magnitude and dephasing, measured by lock-in or through the characteristic time of laser OFF exponential relaxation, exhibit a notable influence of the magnetization direction of the ferromagnetic overlayer. We show experimentally and by numerical simulations that the T-LPE magnitude is determined by the Co anisotropic magnetoresistance. On the other hand, the magnetic field dependence of the dephasing could be described by the influence of the Lorentz force acting perpendiculary to both the Co magnetization and the photocarrier drift directions. Our findings could stimulate the development of fast position sensitive detectors with magnetically tuned magnitude and phase responses.

  1. Method of doping a semiconductor

    International Nuclear Information System (INIS)

    Yang, C.Y.; Rapp, R.A.

    1983-01-01

    A method is disclosed for doping semiconductor material. An interface is established between a solid electrolyte and a semiconductor to be doped. The electrolyte is chosen to be an ionic conductor of the selected impurity and the semiconductor material and electrolyte are jointly chosen so that any compound formed from the impurity and the semiconductor will have a free energy no lower than the electrolyte. A potential is then established across the interface so as to allow the impurity ions to diffuse into the semiconductor. In one embodiment the semiconductor and electrolyte may be heated so as to increase the diffusion coefficient

  2. Magnesium Oxide (MgO) pH-sensitive Sensing Membrane in Electrolyte-Insulator-Semiconductor Structures with CF4 Plasma Treatment.

    Science.gov (United States)

    Kao, Chyuan-Haur; Chang, Chia Lung; Su, Wei Ming; Chen, Yu Tzu; Lu, Chien Cheng; Lee, Yu Shan; Hong, Chen Hao; Lin, Chan-Yu; Chen, Hsiang

    2017-08-03

    Magnesium oxide (MgO) sensing membranes in pH-sensitive electrolyte-insulator-semiconductor structures were fabricated on silicon substrate. To optimize the sensing capability of the membrane, CF 4 plasma was incorporated to improve the material quality of MgO films. Multiple material analyses including FESEM, XRD, AFM, and SIMS indicate that plasma treatment might enhance the crystallization and increase the grain size. Therefore, the sensing behaviors in terms of sensitivity, linearity, hysteresis effects, and drift rates might be improved. MgO-based EIS membranes with CF 4 plasma treatment show promise for future industrial biosensing applications.

  3. Real time spectroscopic ellipsometry for analysis and control of thin film polycrystalline semiconductor deposition in photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Koirala, Prakash; Attygalle, Dinesh; Aryal, Puruswottam; Pradhan, Puja; Chen, Jie [Center for Photovoltaics Innovation and Commercialization and Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States); Marsillac, Sylvain [Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, VA 23529 (United States); Ferlauto, Andre S.; Podraza, Nikolas J.; Collins, Robert W. [Center for Photovoltaics Innovation and Commercialization and Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States)

    2014-11-28

    Real time spectroscopic ellipsometry (RTSE) from the near-infrared to ultraviolet has been applied for analysis of the deposition of polycrystalline thin films that form the basis of two key photovoltaic heterojunction configurations, superstrate SnO{sub 2}/CdS/CdTe and substrate Mo/Cu(In{sub 1−x}Ga{sub x})Se{sub 2}/CdS. The focus of this work is to develop capabilities for monitoring and controlling the key steps in the fabrication of these device structures. Analysis of RTSE data collected during sputter deposition of CdS on a rough SnO{sub 2} transparent top contact provides the time evolution of the CdS effective thickness, or film volume per unit substrate area. This thickness includes interface, bulk, and surface roughness layer components and affects the CdS/CdTe heterojunction performance and the quantum efficiency of the solar cell in the blue region of the solar spectrum. Similarly, analysis of RTSE data collected during co-evaporation of Cu(In{sub 1−x}Ga{sub x})Se{sub 2} (CIGS; x ∼ 0.3) on a rough Mo back contact provides the evolution of a second phase of Cu{sub 2−x}Se within the CIGS layer. During the last stage of CIGS deposition, the In, Ga, and Se co-evaporants convert this Cu{sub 2−x}Se phase to CIGS, and RTSE identifies the endpoint, specifically the time at which complete conversion occurs and single-phase, large-grain CIGS is obtained in this key stage. - Highlights: • Real time spectroscopic ellipsometry (RTSE) study of CdS and CuIn{sub 1−x}Ga{sub x}Se{sub 2} (CIGS) films. • RTSE during CdS deposition provides the evolution of the CdS effective thickness. • RTSE for CIGS film enables to measure and control the composition and thickness. • The work leads to the development of optical models for processing steps.

  4. 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…

  5. Structural properties and sensing characteristics of high-k Ho2O3 sensing film-based electrolyte-insulator-semiconductor

    International Nuclear Information System (INIS)

    Pan, Tung-Ming; Huang, Ming-De

    2011-01-01

    Highlights: → We report the structural properties and sensing characteristics of Ho 2 O 3 sensing membranes deposited on Si substrates by reactive sputtering. → We applied X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy to study the structural and morphological features of these films after they had been subjected to annealing at various temperatures (700 deg. C, 800 deg. C, and 900 deg. C). → The Ho 2 O 3 electrolyte-insulator-semiconductor device annealed at 800 deg. C exhibited a higher sensitivity, a lower hysteresis voltage, and a smaller drift rate than other annealing temperatures. - Abstract: In this study, we report a Ho 2 O 3 electrolyte-insulator-semiconductor (EIS) device films deposited on Si substrates through reactive sputtering. The effect of thermal annealing (700, 800, and 900 deg. C) on the structural and surface properties of Ho 2 O 3 sensing film was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy. We found that the EIS device with a Ho 2 O 3 sensing film annealed at 800 deg. C exhibited a higher sensitivity of ∼57 mV/pH, a lower hysteresis voltage of 2.68 mV, and a smaller drift rate of 2.83 mV h -1 compared to those at other annealing conditions. This improvement can be attributed to the well-crystallized Ho 2 O 3 structure and the large surface roughness.

  6. Microdistribution of Impurities in Semiconductors and its Influence on Photovoltaic Energy Conversion.

    Science.gov (United States)

    Rava, Paolo

    electrically inert complex. The presence of unactivated areas close to the crystal periphery was attributed to a lower concentration of available vacancies due to the presence of the B-defects (vacancy clusters); a 650(DEGREES)C heat treatment changed their structure, possibly releasing vacancies which then participated in donor formation. On the other hand, the areas activated the first time at 450(DEGREES)C have fewer vacancies available the second time for donor formation and therefore are less activated. It was shown that the vacancy-oxygen complex must be the first step in the formation of multivacancy or any multioxygen donor complexes. The role of a factor other than oxygen in donor activation can be revealed only by a microscale analysis such as the one presented here. In fact, the areas in which donor formation is enhanced by 650(DEGREES)C heat treatment are completely undetected in a macroscale analysis, which therefore would lead to a proportionality between oxygen concentration and activated donors. This work shows that the accepted premise that the concentration of oxygen donors is proportional to the oxygen concentration is not generally valid. Multiple p-n junctions have been prepared in b -doped Si through overcompensation near the oxygen periodic concentration maxima by thermal donors generated during an appropriate heat treatment at 450(DEGREES)C. Application of this structure to photovoltaic energy conversion has been investigated. A new solar cell structure based on multiple p-n junctions was developed and tested. An increase in short circuit current was achieved, but at the same time a degradation in open circuit voltage occurred. An interpretation of the experimental data in the light of the results of a computer simulation showed that an overall increase in efficiency can be achieved in this structure with a small and regular junction spacing. The effect of carrier density inhomogeneities in InP and GaAs samples was then investigated. The same scanning

  7. Tunable photovoltaic performance of preferentially oriented rutile TiO2 nanorod photoanodes based dye sensitized solar cells with quasi-state electrolyte.

    Science.gov (United States)

    T C, Sabari Girisun; C, Jeganathan; N, Pavithra; Anandan, Sambandam

    2017-12-20

    Photoanodes made of highly oriented TiO2 nanorod arrays with different aspect ratios were synthesized via one-step hydrothermal technique. Preferentially oriented single crystalline rutile TiO2 was confirmed by the single peak in XRD pattern (2θ=63o, (0 0 2)). FESEM image evidence the growth of an array of nanorods having different geometry with respect to reaction time and solution refreshment rate. The length, diameter and aspect ratio of the nanorods increased with reaction time as 4 hours (1.98 μm, 121 nm, 15.32), 8 hours (4 μm, 185 nm, 22.70), 12 hours (5.6 μm, 242 nm, 27.24) and 16 hours (8 μm, 254 nm, 38.02) respectively. Unlike conventional Dye-Sensitized Solar Cell (DSSC) with a liquid electrolyte, DSSC were fabricated here using 1D rutile TiO2 nanorods based photoanodes, N719 dye and quasi-state electrolyte. The charge transport properties were investigated from current-voltage curves and fitted using one-diode model. Interestingly photovoltaic performance of DSSCs increased exponentially with the length of the nanorod and is attributed to the higher surface to volume ratio, more dye anchoring, and channelized electron transport. Higher photovoltaic performance (Jsc=5.99 mA/cm2, Voc=750 mV, η=3.08%) was observed with photoanodes (16 hours) made of densely packed longest TiO2 nanorods (8 µm, 254 nm). © 2017 IOP Publishing Ltd.

  8. Tunable photovoltaic performance of preferentially oriented rutile TiO2 nanorod photoanode based dye sensitized solar cells with quasi-state electrolyte.

    Science.gov (United States)

    Girisun, T C Sabari; Jeganathan, C; Pavithra, N; Anandan, S

    2018-01-23

    Photoanodes made of highly oriented TiO 2 nanorod (NR) arrays with different aspect ratios were synthesized via a one-step hydrothermal technique. Preferentially oriented single crystalline rutile TiO 2 was confirmed by the single peak in an XRD pattern (2θ = 63°, (0 0 2)). FESEM images evidenced the growth of an array of NRss having different geometries with respect to reaction time and solution refreshment rate. The length, diameter and aspect ratio of the NRs increased with reaction time as 4 h (1.98 μm, 121 nm, 15.32), 8 h (4 μm, 185 nm, 22.70), 12 h (5.6 μm, 242 nm, 27.24) and 16 h (8 μm, 254 nm, 38.02), respectively. Unlike a conventional dye-sensitized solar cell (DSSC) with a liquid electrolyte, DSSCs were fabricated here using one-dimensional rutile TiO 2 NR based photoanodes, N719 dye and a quasi-state electrolyte. The charge transport properties were investigated using current-voltage curves and fitted using the one-diode model. Interestingly the photovoltaic performance of the DSSCs increased exponentially with the length of the NR and was attributed to a higher surface to volume ratio, more dye anchoring, and channelized electron transport. The higher photovoltaic performance (J sc  = 5.99 mA cm -2 , V oc  = 750 mV, η = 3.08%) was observed with photoanodes (16 h) made with the longer, densely packed TiO 2 NRs (8 μm, 254 nm).

  9. Optoelectronic and Photovoltaic Properties of the Air-Stable Organohalide Semiconductor (CH 3 NH 3 ) 3 Bi 2 I 9

    KAUST Repository

    Abulikemu, Mutalifu; Ould-Chikh, Samy; Miao, Xiaohe; Alarousu, Erkki; Banavoth, Murali; Ngongang Ndjawa, Guy Olivier; Barbe, Jeremy; El Labban, Abdulrahman; Amassian, Aram; Del Gobbo, Silvano

    2016-01-01

    Lead halide perovskite materials have shown excellent optoelectronic as well as photovoltaic properties. However, the presence of lead and the chemical instability relegate lead halide perovskites to research applications only. Here, we investigate

  10. Structural, optical and morphological studies of Cd2+ doping in CH3NH3PbI3 perovskite semiconductor at Pb2+ site for photovoltaic applications

    Science.gov (United States)

    Parrey, Khursheed; Warish, Mohd.; Devi, Nisha; Niazi, A.; Aziz, A.; Ansari, S. G.

    2018-05-01

    Doping of semiconductors in a controlled mannner have paramount technological importance as far as the optical and electronic properties of the devices are concerned. Hybrid organic-inorganic perovskites (HOPs) as intrinsic semiconductors have sensational properties required for both the solar photovoltaics and perovskite light emitting diodes. However, undoped and complexity in the dpoing process of HOPs have limited their exploitation in the field of elcronics. In this papper we present the synthesis of HOP semiconductor (CH3NH3PbI3) doped in Pb2+ position by Cd2+. We studied the effect of the incorporation of Cd2+ into the crystalline structure and analysed the changes in the properties like crystal structure, optical absorption and the surface morphology. The structure of HOPs confirmed by X-ray diffraction analysis is tetragonal perovskite type. It can be found that the crystallinity of the samples was enhanced with the doping concentration as the intensity of diffraction peaks were observed to increase with doping. The absorption spectra as obtained from UV-Visible spectrophotometry and Tauc plot analysis indicated that the band gap observed (1.73 eV) is direct type and gets reduced to 1.67 eV with the doping concentration. The red shift may be due to the increase in the size of nanocrystalline material with doping.

  11. Semiconductor band alignment from first principles: a new nonequilibrium Green's function method applied to the CZTSe/CdS interface for photovoltaics

    DEFF Research Database (Denmark)

    Palsgaard, Mattias Lau Nøhr; Crovetto, Andrea; Gunst, Tue

    2016-01-01

    In this paper we present a method to obtain the band offset of semiconductor heterointerfaces from Density Functional Theory together with the nonequilibrium Green's function method. Band alignment and detailed properties of the interface between Cu2ZnSnSe4 and CdS are extracted directly from first...... principles simulations. The interface is important for photovoltaics applications where in particular the band offsets are important for efficiency. The band bending pose a problem for accurate atomistic simulations of band offsets due to its long range. Here we investigate two different methods for dealing...... with band bending directly. One involves doping the materials to induce a shorter screening length. The other method is to apply a voltage bias across the interface to correct for the band bending. The calculated band offsets agree well with previous experimental and theoretical studies and, interestingly...

  12. Zn/sub 3/P/sub 2/ as an improved semiconductor for photovoltaic devices. Final report, July 17, 1976-September 1, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, A.; Dalal, V.; Devaney, W.E.; Fagen, E.A.; Hall, R.B.; Masi, J.V.; Warfield, G.; Wyeth, N.C.

    1978-01-01

    The goal of this work was to evaluate the suitability of Zn/sub 3/P/sub 2/ as a potentially low cost, high conversion efficiency material for photovoltaic devices. The important results of the research are presented and discussed. The major accomplishments of this work are: (1) the development of a vapor transport method for the growth of large single crystals; (2) the development of two methods of thin film growth: vacuum evaporation and close space transport; (3) the determination of the optical constants of Zn/sub 3/P/sub 2/ including the indices of refraction, the optical absorption coefficient, and the ultra-violet to visible reflectivity spectra; (4) a determination of the factors which influence the electrical conductivity and how these relate to the defect chemistry of Zn/sub 3/P/sub 2/; (5) measurement of the barrier height of metal-Zn/sub 3/P/sub 2/ contacts and the development of a model which relates the barrier height to the properties of the metal-semiconductor interface; (6) measurement of the minority carrier diffusion length in Zn/sub 3/P/sub 2/; (7) the development of several single and double layer anti-reflection coatings; and (8) the development of Schottky barrier photovoltaic devices employing a grid device and transparent metal film design, with conversion efficiencies as high as 6.08% (total area) or 7.6% (active area).

  13. Transparent contacts for stacked compound photovoltaic cells

    Science.gov (United States)

    Tauke-Pedretti, Anna; Cederberg, Jeffrey; Nielson, Gregory N.; Okandan, Murat; Cruz-Campa, Jose Luis

    2016-11-29

    A microsystems-enabled multi-junction photovoltaic (MEM-PV) cell includes a first photovoltaic cell having a first junction, the first photovoltaic cell including a first semiconductor material employed to form the first junction, the first semiconductor material having a first bandgap. The MEM-PV cell also includes a second photovoltaic cell comprising a second junction. The second photovoltaic cell comprises a second semiconductor material employed to form the second junction, the second semiconductor material having a second bandgap that is less than the first bandgap, the second photovoltaic cell further comprising a first contact layer disposed between the first junction of the first photovoltaic cell and the second junction of the second photovoltaic cell, the first contact layer composed of a third semiconductor material having a third bandgap, the third bandgap being greater than or equal to the first bandgap.

  14. Semiconductor materials and their properties

    NARCIS (Netherlands)

    Reinders, Angelina H.M.E.; Verlinden, Pierre; van Sark, Wilfried; Freundlich, Alexandre; Reinders, Angele; Verlinden, Pierre; van Sark, Wilfried; Freundlich, Alexandre

    2017-01-01

    Semiconductor materials are the basic materials which are used in photovoltaic (PV) devices. This chapter introduces solid-state physics and semiconductor properties that are relevant to photovoltaics without spending too much time on unnecessary information. Usually atoms in the group of

  15. Organic photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Within the International Conference and Exhibition at 16th September,2010 at the Maritim Hotel (Wuerzburg, Federal Republic of Germany) the following lectures were held: (1) History of Organic Photovoltaics (Niyazi Serdar Sariciftci); (2) PV Activities at the ZAE Bayern (Vladimir Dyakonov); (3) Progress in Solid State DSC (Peter Erk); (4) Polymer Semiconductors for OPV (Mats Andersson); (5) Fullerene Derivative N-Types in Organic Solar Cells (David Kronholm); (6) Modelling Charge-Transport in Organic Photovoltaic Materials (Jenny Nelson); (7) Multi Junction Modules R and D Status and Outlook (Paul Blom); (8) Imaging Technologies for Organic Solar Cells (Jonas Bachmann); (9) Production of Multi-junction Organic Photovoltaic Cells and Modules (Martin Pfeiffer); (10) Upscaling of Polymer Solar Cell Fabrication Using Full Roll-to-roll Processing (Frederik Christian Krebs); (11) Industrial Aspects and Large Scale OPV Production (Jens Hauch).

  16. High dielectric constant PrYxOy sensing films electrolyte-insulator-semiconductor pH-sensor for the detection of urea

    International Nuclear Information System (INIS)

    Wu, Min-Hsien; Lee, Cheng-Da; Pan, Tung-Ming

    2009-01-01

    In this paper, we describe the structural and sensing properties of high-k PrY x O y sensing films deposited on Si substrates through reactive co-sputtering. Secondary ion mass spectrometry and atomic force microscopy were employed to analyze the compositional and morphological features of these films after annealing at various temperatures. The electrolyte-insulator-semiconductor (EIS) device incorporating a PrY x O y sensing membrane that had been annealed at 800 o C exhibited good sensing characteristics, including a high sensitivity (59.07 mV pH -1 in solutions from pH 2 to 12), a low hysteresis voltage (2.4 mV in the pH loop 7 → 4 → 7 → 10 → 7), and a small drift rate (0.62 mV h -1 in the buffer solution at pH 7). The PrY x O y EIS device also showed a high selective response towards H + . This improvement can be attributed to the small number of crystal defects and the large surface roughness. In addition, the enzymatic EIS-based urea biosensor incorporating a high-k PrY x O y sensing film annealed at 800 o C allowed the potentiometric analysis of urea, at concentrations ranging from 1 to 16 mM, with a sensitivity of 9.59 mV mM -1 .

  17. Structural Properties and Sensing Performance of CeYxOy Sensing Films for Electrolyte-Insulator-Semiconductor pH Sensors.

    Science.gov (United States)

    Pan, Tung-Ming; Wang, Chih-Wei; Chen, Ching-Yi

    2017-06-07

    In this study we developed CeY x O y sensing membranes displaying super-Nernstian pH-sensitivity for use in electrolyte-insulator-semiconductor (EIS) pH sensors. We examined the effect of thermal annealing on the structural properties and sensing characteristics of the CeY x O y sensing membranes deposited through reactive co-sputtering onto Si substrates. X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy revealed the structural, morphological, and chemical features, respectively, of the CeY x O y films after their annealing at 600-900 °C. Among the tested systems, the CeY x O y EIS device prepared with annealing at 800 °C exhibited the highest sensitivity (78.15 mV/pH), the lowest hysteresis voltage (1.4 mV), and the lowest drift rate (0.85 mV/h). Presumably, these annealing conditions optimized the stoichiometry of (CeY)O 2 in the film and its surface roughness while suppressing silicate formation at the CeY x O y -Si interface. We attribute the super-Nernstian pH-sensitivity to the incorporation of Y ions in the Ce framework, thereby decreasing the oxidation state Ce (Ce 4+  → Ce 3+ ) and resulting in less than one electron transferred per proton in the redox reaction.

  18. Functionalized vertically aligned ZnO nanorods for application in electrolyte-insulator-semiconductor based pH sensors and label-free immuno-sensors

    International Nuclear Information System (INIS)

    Kumar, Narendra; Senapati, Sujata; Kumar, Jitendra; Panda, Siddhartha; Kumar, Satyendra

    2016-01-01

    Vertically aligned ZnO nanorods were grown on a SiO 2 /Si surface by optimization of the temperature and atmosphere for annealing of the seed. The seed layer annealed at 500 °C in vacuum provided well separated and uniform seeds which also provided the best condition to get densely packed, uniformly distributed, and vertically aligned nanorods. These nanorods grown on the substrates were used to fabricate electrolyte-insulator-semiconductor (EIS) devices for pH sensing. Etching of ZnO at acidic pH prevents the direct use of nanorods for pH sensing. Therefore, the nanorods functionalised with 3-aminopropyltriethoxysilane (APTES) were utilized for pH sensing and showed the pH sensitivity of 50.1 mV/pH. APTES is also known to be used as a linker to immobilize biomolecules (such as antibodies). The EIS device with APTES functionalized nanorods was used for the label free detection of prostate-specific antigen (PSA). Finally, voltage shifts of 23 mV and 35 mV were observed with PSA concentrations of 1 ng/ml and 100 ng/ml, respectively. (paper)

  19. Detection of pH and Enzyme-Free H2O2 Sensing Mechanism by Using GdO x Membrane in Electrolyte-Insulator-Semiconductor Structure.

    Science.gov (United States)

    Kumar, Pankaj; Maikap, Siddheswar; Qiu, Jian-Tai; Jana, Surajit; Roy, Anisha; Singh, Kanishk; Cheng, Hsin-Ming; Chang, Mu-Tung; Mahapatra, Rajat; Chiu, Hsien-Chin; Yang, Jer-Ren

    2016-12-01

    A 15-nm-thick GdO x membrane in an electrolyte-insulator-semiconductor (EIS) structure shows a higher pH sensitivity of 54.2 mV/pH and enzyme-free hydrogen peroxide (H2O2) detection than those of the bare SiO2 and 3-nm-thick GdO x membranes for the first time. Polycrystalline grain and higher Gd content of the thicker GdO x films are confirmed by transmission electron microscopy (TEM) and X-ray photo-electron spectroscopy (XPS), respectively. In a thicker GdO x membrane, polycrystalline grain has lower energy gap and Gd(2+) oxidation states lead to change Gd(3+) states in the presence of H2O2, which are confirmed by electron energy loss spectroscopy (EELS). The oxidation/reduction (redox) properties of thicker GdO x membrane with higher Gd content are responsible for detecting H2O2 whereas both bare SiO2 and thinner GdO x membranes do not show sensing. A low detection limit of 1 μM is obtained due to strong catalytic activity of Gd. The reference voltage shift increases with increase of the H2O2 concentration from 1 to 200 μM owing to more generation of Gd(3+) ions, and the H2O2 sensing mechanism has been explained as well.

  20. Capacitive electrolyte-insulator-semiconductor structures functionalised with a polyelectrolyte/enzyme multilayer: New strategy for enhanced field-effect biosensing

    Energy Technology Data Exchange (ETDEWEB)

    Abouzar, Maryam H.; Poghossian, Arshak; Schoening, Michael J. [Institute of Nano- and Biotechnologies, Aachen University of Applied Sciences, Juelich (Germany); Institute of Bio- and Nanosystems (IBN-2), Research Centre Juelich GmbH, Juelich (Germany); Siqueira, Jose R. Jr.; Oliveira, Osvaldo N. Jr. [Physics Institute of Sao Carlos, University of Sao Paulo, Sao Carlos (Brazil); Moritz, Werner [Institute of Chemistry, Humboldt University Berlin (Germany)

    2010-04-15

    A novel strategy for enhanced field-effect biosensing using capacitive electrolyte-insulator-semiconductor (EIS) structures functionalised with pH-responsive weak polyelectrolyte/enzyme or dendrimer/enzyme multilayers is presented. The feasibility of the proposed approach is exemplarily demonstrated by realising a penicillin biosensor based on a capacitive p-Si-SiO{sub 2} EIS structure functionalised with a poly(allylamine hydrochloride) (PAH)/penicillinase and a poly(amidoamine) dendrimer/penicillinase multilayer. The developed sensors response to changes in both the local pH value near the gate surface and the charge of macromolecules induced via enzymatic reaction, resulting in a higher sensitivity. For comparison, an EIS penicillin biosensor with adsorptively immobilised penicillinase has been also studied. The highest penicillin sensitivity of 100 mV/dec has been observed for the EIS sensor functionalised with the PAH/penicillinase multilayer. The lower and upper detection limit was around 20 {mu}M and 10 mM, respectively. In addition, an incorporation of enzymes in a multilayer prepared by layer-by-layer technique provides a larger amount of immobilised enzymes per sensor area, reduces enzyme leaching effects and thus, enhances the biosensor lifetime (the loss of penicillin sensitivity after 2 months was 10-12%). (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  1. Physical effects of DCNQI derivatives doping as an N type organic semiconductor in organic photovoltaic cell performance.

    Science.gov (United States)

    Lee, Joo Hyung; Oh, Se Young

    2014-08-01

    In the previous work, we have reported that organic photovoltaic (OPV) cells using DMDCNQI as an n-type second dopant material showed a high power conversion efficiency (PCE). In the present work, we have synthesized a novel DHDCNQI with long alkyl chains to improve the compatibility between the DHDCNQI dopant molecule and host P3HT polymer. We have fabricated OPV cells consisting of ITO/PEDOT:PSS/P3HT:PCBM:DHDCNQI/Al. We have investigated the characteristics of theses OPV cells using DCNQI derivative dopants from the measurements of the incident photon-to-current collection efficiency and photocurrent. The OPV cell using 3 wt% DHDCNQI exhibited a high PCE of 3.29% due to the high charge separation efficiency, good compatibility and low trap site effect.

  2. Defects in Cu(In,Ga)Se{sub 2} chalcopyrite semiconductors: a comparative study of material properties, defect states, and photovoltaic performance

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Qing; Gunawan, Oki; Copel, Matthew; Reuter, Kathleen B; Chey, S Jay; Mitzi, David B [IBM T.J. Watson Research Center, Yorktown Heights, NY (United States); Deline, Vaughn R [IBM Almaden Resesarch Center, San Jose, CA (United States)

    2011-10-15

    Understanding defects in Cu(In,Ga)(Se,S){sub 2} (CIGS), especially correlating changes in the film formation process with differences in material properties, photovoltaic (PV) device performance, and defect levels extracted from admittance spectroscopy, is a critical but challenging undertaking due to the complex nature of this polycrystalline compound semiconductor. Here we present a systematic comparative study wherein varying defect density levels in CIGS films were intentionally induced by growing CIGS grains using different selenium activity levels. Material characterization results by techniques including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, secondary ion mass spectrometry, X-ray photoelectron spectroscopy, and medium energy ion scattering indicate that this process variation, although not significantly affecting CIGS grain structure, crystal orientation, or bulk composition, leads to enhanced formation of a defective chalcopyrite layer with high density of indium or gallium at copper antisite defects ((In, Ga){sub Cu}) near the CIGS surface, for CIGS films grown with insufficient selenium supply. This defective layer or the film growth conditions associated with it is further linked with observed current-voltage characteristics, including rollover and crossover behavior, and a defect state at around 110 meV (generally denoted as the N1 defect) commonly observed in admittance spectroscopy. The impact of the (In, Ga){sub Cu} defects on device PV performance is also established. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Flexo-photovoltaic effect.

    Science.gov (United States)

    Yang, Ming-Min; Kim, Dong Jik; Alexe, Marin

    2018-04-19

    It is highly desirable to discover photovoltaic mechanisms that enable a higher efficiency of solar cells. Here, we report that the bulk photovoltaic effect, which is free from the thermodynamic Shockley-Queisser limit but usually manifested only in noncentrosymmetric (piezoelectric or ferroelectric) materials, can be realized in any semiconductor, including silicon, by mediation of flexoelectric effect. We introduce strain gradients using either an atomic force microscope or a micron-scale indentation system, creating giant photovoltaic currents from centrosymmetric single crystals of SrTiO 3 , TiO 2 , and Si. This strain-gradient-induced bulk photovoltaic effect, which we call the flexo-photovoltaic effect, functions in the absence of a p - n junction. This finding may extend present solar cell technologies by boosting the solar energy conversion efficiency from a wide pool of established semiconductors. Copyright © 2018, American Association for the Advancement of Science.

  4. Method of making photovoltaic cell

    Science.gov (United States)

    Cruz-Campa, Jose Luis; Zhou, Xiaowang; Zubia, David

    2017-06-20

    A photovoltaic solar cell comprises a nano-patterned substrate layer. A plurality of nano-windows are etched into an intermediate substrate layer to form the nano-patterned substrate layer. The nano-patterned substrate layer is positioned between an n-type semiconductor layer composed of an n-type semiconductor material and a p-type semiconductor layer composed of a p-type semiconductor material. Semiconductor material accumulates in the plurality of nano-windows, causing a plurality of heterojunctions to form between the n-type semiconductor layer and the p-type semiconductor layer.

  5. Enhanced photovoltaic performance of ultrathin Si solar cells via semiconductor nanocrystal sensitization: energy transfer vs. optical coupling effects.

    Science.gov (United States)

    Hoang, Son; Ashraf, Ahsan; Eisaman, Matthew D; Nykypanchuk, Dmytro; Nam, Chang-Yong

    2016-03-21

    Excitonic energy transfer (ET) offers exciting opportunities for advances in optoelectronic devices such as solar cells. While recent experimental attempts have demonstrated its potential in both organic and inorganic photovoltaics (PVs), what remains to be addressed is quantitative understanding of how different ET modes contribute to PV performance and how ET contribution is differentiated from the classical optical coupling (OC) effects. In this study, we implement an ET scheme using a PV device platform, comprising CdSe/ZnS nanocrystal energy donor and 500 nm-thick ultrathin Si acceptor layers, and present the quantitative mechanistic description of how different ET modes, distinguished from the OC effects, increase the light absorption and PV efficiency. We find that nanocrystal sensitization enhances the short circuit current of ultrathin Si solar cells by up to 35%, of which the efficient ET, primarily driven by a long-range radiative mode, contributes to 38% of the total current enhancement. These results not only confirm the positive impact of ET but also provide a guideline for rationally combining the ET and OC effects for improved light harvesting in PV and other optoelectronic devices.

  6. In situ UV-visible absorption during spin-coating of organic semiconductors: A new probe for organic electronics and photovoltaics

    KAUST Repository

    Abdelsamie, Maged

    2014-01-01

    Spin-coating is the most commonly used technique for the lab-scale production of solution processed organic electronic, optoelectronic and photovoltaic devices. Spin-coating produces the most efficient solution-processed organic solar cells and has been the preferred approach for rapid screening and optimization of new organic semiconductors and formulations for electronic and optoelectronic applications, both in academia and in industrial research facilities. In this article we demonstrate, for the first time, a spin-coating experiment monitored in situ by time resolved UV-visible absorption, the most commonly used, simplest, most direct and robust optical diagnostic tool used in organic electronics. In the first part, we successfully monitor the solution-to-solid phase transformation and thin film formation of poly(3-hexylthiophene) (P3HT), the de facto reference conjugated polymer in organic electronics and photovoltaics. We do so in two scenarios which differ by the degree of polymer aggregation in solution, prior to spin-coating. We find that a higher degree of aggregation in the starting solution results in small but measurable differences in the solid state, which translate into significant improvements in the charge carrier mobility of organic field-effect transistors (OFET). In the second part, we monitor the formation of a bulk heterojunction photoactive layer based on a P3HT-fullerene blend. We find that the spin-coating conditions that lead to slower kinetics of thin film formation favour a higher degree of polymer aggregation in the solid state and increased conjugation length along the polymer backbone. Using this insight, we devise an experiment in which the spin-coating process is interrupted prematurely, i.e., after liquid ejection is completed and before the film has started to form, so as to dramatically slow the thin film formation kinetics, while maintaining the same thickness and uniformity. These changes yield substantial improvements to the

  7. Effect of nanostructured electrode architecture and semiconductor deposition strategy on the photovoltaic performance of quantum dot sensitized solar cells

    International Nuclear Information System (INIS)

    Samadpour, Mahmoud; Giménez, Sixto; Boix, Pablo P.; Shen, Qing; Calvo, Mauricio E.; Taghavinia, Nima; Azam Iraji zad; Toyoda, Taro; Míguez, Hernán

    2012-01-01

    Highlights: ► Electrode nanostructure and quantum dot growth method have a clear influence in the final quantum dot solar cell performance. ► Higher V oc values are systematically obtained for TiO 2 morphologies with decreasing surface area. ► Higher V oc values are systematically obtained for cells using CBD growth method in comparison with SILAR method. - Abstract: Here we analyze the effect of two relevant aspects related to cell preparation on quantum dot sensitized solar cells (QDSCs) performance: the architecture of the TiO 2 nanostructured electrode and the growth method of quantum dots (QD). Particular attention is given to the effect on the photovoltage, V oc , since this parameter conveys the main current limitation of QDSCs. We have analyzed electrodes directly sensitized with CdSe QDs grown by chemical bath deposition (CBD) and successive ionic layer adsorption and reaction (SILAR). We have carried out a systematic study comprising structural, optical, photophysical and photoelectrochemical characterization in order to correlate the material properties of the photoanodes with the functional performance of the manufactured QDSCs. The results show that the correspondence between photovoltaic conversion efficiency and the surface area of TiO 2 depends on the QDs deposition method. Higher V oc values are systematically obtained for TiO 2 morphologies with decreasing surface area and for cells using CBD growth method. This is systematically correlated to a higher recombination resistance of CBD sensitized electrodes. Electron injection kinetics from QDs into TiO 2 also depends on both the TiO 2 structure and the QDs deposition method, being systematically faster for CBD. Only for electrodes prepared with small TiO 2 nanoparticles SILAR method presents better performance than CBD, indicating that the small pore size disturb the CBD growth method. These results have important implications for the optimization of QDSCs.

  8. Preparation and characterization of semiconductor thin film cells of n-CdSe and CdSel-x Tex. Application in solar cells of liquid union

    International Nuclear Information System (INIS)

    Gutierrez, M.A.

    1987-01-01

    The development of the new energy sources, constitutes one of the most active and changing investigation areas of nowday. Within this frame, the conservation of photovoltaic solar energy, has taken a particular importance, as these systems become directly the photovoltaic solar energy, which incises on a semiconductor, in electric energy. In spite of this advantage, the use of photovoltaic systems is limited, being the main reason for this, the still high cost of the devices. One of the objectives of this Memory is to contribute to the reduction of these photovoltaic devices by using available methods for the preparation of photosensitive material, and for the union formation. The chosen preparation method is the electrochemical one and the electric field is made up in the interphase semiconductor/electrolyte, dipping the semiconductor in a convenient electrolyte. Summarizing, it can be said that the Memory's objetive presented is to discover the experiences realized in the electrochemical preparation of the n-CdSel-x Tex and its characterization by chemical analysis, X-rays difraction, electronic microscope of swept, optical techniques and photoelectrochemical methods. From the data obtained with these techniques, a study of the physical parameters evolution which determine the photovoltaic properties of the semiconductor, is made, as: the concentration of minoritary carriers, ND, and the diffusion length of these carriers, LP. Finally, taking into account the results obtained by the characterization of n-CdSe and CdSel-x Tex, is made from the construction of the photoelectrochemical cell, using two kinds of electrolyte: sulfide- polysulfide ands ferro-ferricyanide. (Author)

  9. Critical role of the semiconductor-electrolyte interface in photocatalytic performance for water-splitting reactions using Ta3N5 particles

    KAUST Repository

    Nurlaela, Ela

    2014-08-26

    Distinct photocatalytic performance was observed when Ta3N 5 was synthesized from commercially available Ta2O 5 or from Ta2O5 prepared from TaCl5 via the sol-gel route. With respect to photocatalytic O2 evolution with Ag+ as a sacrificial reagent, the Ta3N5 produced from commercial Ta2O5 exhibited higher activity than the Ta3N5 produced via the sol-gel route. When the Ta3N5 photocatalysts were decorated with Pt nanoparticles in a similar manner, the Ta3N5 from the sol-gel route exhibited higher photocatalytic hydrogen evolution activity from a 10% aqueous methanol solution than Ta3N5 prepared from commercial Ta2O5 where no hydrogen can be detected. Detailed surface and bulk characterizations were conducted to obtain fundamental insight into the resulting photocatalytic activities. The characterization techniques, including XRD, elemental analysis, Raman spectroscopy, UV-vis spectroscopy, and surface-area measurements, revealed only negligible differences between these two photocatalysts. Our thorough characterization of the surface properties demonstrated that the very thin outermost layer of Ta3N5, with a thickness of a few nanometers, consists of either the reduced state of tantalum (TaN) or an amorphous phase. The extent of this surface layer was likely dependent on the nature of precursor oxide surfaces. DFT calculations based on partially oxidized Ta3N4.83O0.17 and N deficient Ta3N4.83 consisting of reduced Ta species well described the optoelectrochemical properties obtained from the experiments. Electrochemical and Mott-Schottky analyses demonstrated that the surface layer drastically affects the energetic picture at the semiconductor-electrolyte interface, which can consequently affect the photocatalytic performance. Chemical etching of the surface of Ta3N5 particles to remove this surface layer unites the photocatalytic properties with the photocatalytic performance of these two materials. Mott-Schottky plots of these chemically etched Ta3N5 materials

  10. Photovoltaics fundamentals, technology and practice

    CERN Document Server

    Mertens, Konrad

    2013-01-01

    Concise introduction to the basic principles of solar energy, photovoltaic systems, photovoltaic cells, photovoltaic measurement techniques, and grid connected systems, overviewing the potential of photovoltaic electricity for students and engineers new to the topic After a brief introduction to the topic of photovoltaics' history and the most important facts, Chapter 1 presents the subject of radiation, covering properties of solar radiation, radiation offer, and world energy consumption. Chapter 2 looks at the fundamentals of semiconductor physics. It discusses the build-up of semiconducto

  11. Photoeffects of Semiconductor Electrolyte Interfaces

    Science.gov (United States)

    1985-03-01

    effect of FeTiO3 had very’ little effect on the overall properties "of Fe 0? single crystals. On the other hand the effect on the Fe/Ti oxide thin...transfer alloy of Fe20 3 and FeTiO3 as an interesting candidate for use as a photoelectrode. a-iron oxide and iron titanate crystallize’in essentially...the same rhombohedral space group (RSC/R•) with similar lattice constants. Conse- quently Fe?( 3 and- FeTiO3 form a solid solution over the whole

  12. Plastic photovoltaic devices

    OpenAIRE

    Niyazi Serdar Sariciftci

    2004-01-01

    The development of organic, polymer-based photovoltaic elements has introduced the possibility of obtaining cheap and easy-to-produce energy from light. Photoinduced electron transfer from donor-type semiconducting polymers onto acceptor-type polymers or molecules, such as C60, is the basic phenomenon utilized in these photovoltaic devices. This process mimics the early photo-effects in natural photosynthesis. The polymeric semiconductors combine the photoelectrical properties of inorganic se...

  13. Materials for Photovoltaic Applications

    Science.gov (United States)

    Dimova-Malinovska, Doriana

    Energy priorities are changing nowadays. As mankind will probably have to face energy crisis, factors such as energy independence, energy security, stability of energy supply and the variety of energy sources become much more vital these days. Photovoltaics is exceptional compared to other renewable sources of energy due to its wide opportunity to gain energetic and environmental benefits. An overview of the present state of knowledge of the materials aspects of photovoltaic cells will be given, and new semiconductor materials, including nanomaterials, with potential for application in photovoltaic devices will be identified.

  14. Photolithographically Patterned TiO2 Films for Electrolyte-Gated Transistors.

    Science.gov (United States)

    Valitova, Irina; Kumar, Prajwal; Meng, Xiang; Soavi, Francesca; Santato, Clara; Cicoira, Fabio

    2016-06-15

    Metal oxides constitute a class of materials whose properties cover the entire range from insulators to semiconductors to metals. Most metal oxides are abundant and accessible at moderate cost. Metal oxides are widely investigated as channel materials in transistors, including electrolyte-gated transistors, where the charge carrier density can be modulated by orders of magnitude upon application of relatively low electrical bias (2 V). Electrolyte gating offers the opportunity to envisage new applications in flexible and printed electronics as well as to improve our current understanding of fundamental processes in electronic materials, e.g. insulator/metal transitions. In this work, we employ photolithographically patterned TiO2 films as channels for electrolyte-gated transistors. TiO2 stands out for its biocompatibility and wide use in sensing, electrochromics, photovoltaics and photocatalysis. We fabricated TiO2 electrolyte-gated transistors using an original unconventional parylene-based patterning technique. By using a combination of electrochemical and charge carrier transport measurements we demonstrated that patterning improves the performance of electrolyte-gated TiO2 transistors with respect to their unpatterned counterparts. Patterned electrolyte-gated (EG) TiO2 transistors show threshold voltages of about 0.9 V, ON/OFF ratios as high as 1 × 10(5), and electron mobility above 1 cm(2)/(V s).

  15. Photovoltaic technologies

    International Nuclear Information System (INIS)

    Bagnall, Darren M.; Boreland, Matt

    2008-01-01

    Photovoltaics is already a billion dollar industry. It is experiencing rapid growth as concerns over fuel supplies and carbon emissions mean that governments and individuals are increasingly prepared to ignore its current high costs. It will become truly mainstream when its costs are comparable to other energy sources. At the moment, it is around four times too expensive for competitive commercial production. Three generations of photovoltaics have been envisaged that will take solar power into the mainstream. Currently, photovoltaic production is 90% first-generation and is based on silicon wafers. These devices are reliable and durable, but half of the cost is the silicon wafer and efficiencies are limited to around 20%. A second generation of solar cells would use cheap semiconductor thin films deposited on low-cost substrates to produce devices of slightly lower efficiency. A number of thin-film device technologies account for around 5-6% of the current market. As second-generation technology reduces the cost of active material, the substrate will eventually be the cost limit and higher efficiency will be needed to maintain the cost-reduction trend. Third-generation devices will use new technologies to produce high-efficiency devices. Advances in nanotechnology, photonics, optical metamaterials, plasmonics and semiconducting polymer sciences offer the prospect of cost-competitive photovoltaics. It is reasonable to expect that cost reductions, a move to second-generation technologies and the implementation of new technologies and third-generation concepts can lead to fully cost-competitive solar energy in 10-15 years. (author)

  16. Photovoltaic radiation detector element

    International Nuclear Information System (INIS)

    Agouridis, D.C.

    1980-01-01

    A radiation detector element is formed of a body of semiconductor material, a coating on the body which forms a photovoltaic junction therewith, and a current collector consisting of narrow metallic strips, the aforesaid coating having an opening therein in the edge of which closely approaches but is spaced from the current collector strips

  17. In situ UV-visible absorption during spin-coating of organic semiconductors: A new probe for organic electronics and photovoltaics

    KAUST Repository

    Abdelsamie, Maged; Zhao, Kui; Niazi, Muhammad Rizwan; Chou, Kang Wei; Amassian, Aram

    2014-01-01

    Spin-coating is the most commonly used technique for the lab-scale production of solution processed organic electronic, optoelectronic and photovoltaic devices. Spin-coating produces the most efficient solution-processed organic solar cells and has

  18. Redox properties of small semiconductor particles

    International Nuclear Information System (INIS)

    Liver, N.; Nitzan, A.

    1992-01-01

    The size dependence of electrical and thermodynamic quantities of intermediate-sized semiconductor particles in an electrolyte solution with a given redox pair are studied. The equilibrium constant for this system is then derived based on the relationship of the electrolytic redox components to the size, charges, and concentration of the semiconductor particles. 25 refs., 9 figs., 1 tab

  19. 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.

  20. Organic semiconductor crystals.

    Science.gov (United States)

    Wang, Chengliang; Dong, Huanli; Jiang, Lang; Hu, Wenping

    2018-01-22

    Organic semiconductors have attracted a lot of attention since the discovery of highly doped conductive polymers, due to the potential application in field-effect transistors (OFETs), light-emitting diodes (OLEDs) and photovoltaic cells (OPVs). Single crystals of organic semiconductors are particularly intriguing because they are free of grain boundaries and have long-range periodic order as well as minimal traps and defects. Hence, organic semiconductor crystals provide a powerful tool for revealing the intrinsic properties, examining the structure-property relationships, demonstrating the important factors for high performance devices and uncovering fundamental physics in organic semiconductors. This review provides a comprehensive overview of the molecular packing, morphology and charge transport features of organic semiconductor crystals, the control of crystallization for achieving high quality crystals and the device physics in the three main applications. We hope that this comprehensive summary can give a clear picture of the state-of-art status and guide future work in this area.

  1. Tin Dioxide Electrolyte-Gated Transistors Working in Depletion and Enhancement Modes.

    Science.gov (United States)

    Valitova, Irina; Natile, Marta Maria; Soavi, Francesca; Santato, Clara; Cicoira, Fabio

    2017-10-25

    Metal oxide semiconductors are interesting for next-generation flexible and transparent electronics because of their performance and reliability. Tin dioxide (SnO 2 ) is a very promising material that has already found applications in sensing, photovoltaics, optoelectronics, and batteries. In this work, we report on electrolyte-gated, solution-processed polycrystalline SnO 2 transistors on both rigid and flexible substrates. For the transistor channel, we used both unpatterned and patterned SnO 2 films. Since decreasing the SnO 2  area in contact with the electrolyte increases the charge-carrier density, patterned transistors operate in the depletion mode, whereas unpatterned ones operate in the enhancement mode. We also fabricated flexible SnO 2 transistors that operate in the enhancement mode that can withstand moderate mechanical bending.

  2. Dye-Sensitized Approaches to Photovoltaics

    Science.gov (United States)

    Grätzel, Michael

    2008-03-01

    Sensitization of wide band-gap semiconductors to photons of energy less than the band-gap is a key step in two technically important processes - panchromatic photography and photoelectrochemical solar cells. In both cases the photosensitive species is not the semiconductor - silver halide or metal oxide - but rather an electrochemically active dye. The gap between the highest occupied molecular level (HOMO) and the lowest unoccupied molecular level (LUMO) is less than the band-gap of the semiconductor with which it is associated. It can therefore absorb light of a wavelength longer than that to which the semiconductor itself is sensitive. The electrochemical process is initiated when the dye molecule relaxes from its photoexcited level by electron injection into the semiconductor, which therefore acts as a photoanode. If the dye is in contact with a redox electrolyte, the negative charge represented by the lost electron can be recovered from the reduced state of the redox system, which in return is regenerated by charge transfer from a cathode. An external load completes the electrical circuit. The system therefore represents a conversion of the energy of absorbed photons into an electrical current by a regenerative device in every functional respect analogous to a solid-state photovoltaic cell. As in any engineering system, choice of materials, their optimization and their synergy are essential to efficient operation. While a semiconductor-electrolyte contact is analogous to a Schottky contact, in that a barrier is established between two materials of different conduction mechanism, with the possibility of optical absorption, charge carrier pair generation and separation, it should be remembered that the photogenerated valence band hole in the semiconductor represents a powerful oxidizing agent. Given that the band-gap is related to the strength and therefore the stability of chemical bonding within the semiconductor, for narrow-gap materials the most likely

  3. Asphaltene based photovoltaic devices

    Science.gov (United States)

    Chianelli, Russell R.; Castillo, Karina; Gupta, Vipin; Qudah, Ali M.; Torres, Brenda; Abujnah, Rajib E.

    2016-03-22

    Photovoltaic devices and methods of making the same, are disclosed herein. The cell comprises a photovoltaic device that comprises a first electrically conductive layer comprising a photo-sensitized electrode; at least one photoelectrochemical layer comprising metal-oxide particles, an electrolyte solution comprising at least one asphaltene fraction, wherein the metal-oxide particles are optionally dispersed in a surfactant; and a second electrically conductive layer comprising a counter-electrode, wherein the second electrically conductive layer comprises one or more conductive elements comprising carbon, graphite, soot, carbon allotropes or any combinations thereof.

  4. Polymer Electrolytes

    Science.gov (United States)

    Hallinan, Daniel T.; Balsara, Nitash P.

    2013-07-01

    This review article covers applications in which polymer electrolytes are used: lithium batteries, fuel cells, and water desalination. The ideas of electrochemical potential, salt activity, and ion transport are presented in the context of these applications. Potential is defined, and we show how a cell potential measurement can be used to ascertain salt activity. The transport parameters needed to fully specify a binary electrolyte (salt + solvent) are presented. We define five fundamentally different types of homogeneous electrolytes: type I (classical liquid electrolytes), type II (gel electrolytes), type III (dry polymer electrolytes), type IV (dry single-ion-conducting polymer electrolytes), and type V (solvated single-ion-conducting polymer electrolytes). Typical values of transport parameters are provided for all types of electrolytes. Comparison among the values provides insight into the transport mechanisms occurring in polymer electrolytes. It is desirable to decouple the mechanical properties of polymer electrolyte membranes from the ionic conductivity. One way to accomplish this is through the development of microphase-separated polymers, wherein one of the microphases conducts ions while the other enhances the mechanical rigidity of the heterogeneous polymer electrolyte. We cover all three types of conducting polymer electrolyte phases (types III, IV, and V). We present a simple framework that relates the transport parameters of heterogeneous electrolytes to homogeneous analogs. We conclude by discussing electrochemical stability of electrolytes and the effects of water contamination because of their relevance to applications such as lithium ion batteries.

  5. Photovoltaic System in Progress

    DEFF Research Database (Denmark)

    Shoro, Ghulam Mustafa; Hussain, Dil Muhammad Akbar; Sera, Dezso

    2013-01-01

    This paper provides a comprehensive update on photovoltaic (PV) technologies and the materials. In recent years, targeted research advancement has been made in the photovoltaic cell technologies to reduce cost and increase efficiency. Presently, several types of PV solar panels are commercially...... falls in the third generation PV technologies. However, Multi-junction Cells are still considered new and have not yet achieved commercialization status. The fundamental change observed among all generations has been how the semiconductor material is employed and the development associated with crystal...

  6. Hybrid polymer-inorganic photovoltaic cells

    NARCIS (Netherlands)

    Beek, W.J.E.; Janssen, R.A.J.; Merhari, L.

    2009-01-01

    Composite materials made from organic conjugated polymers and inorganic semiconductors such as metal oxides attract considerable interest for photovoltaic applications. Hybrid polymer-inorganic solar cells offer the opportunity to combine the beneficial properties of the two materials in charge

  7. Solid State Photovoltaic Research Branch

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

  8. Solar spectrum conversion for photovoltaics using nanoparticles

    OpenAIRE

    Sark, W.G.J.H.M. van; Meijerink, A.; Schropp, R.E.I.

    2012-01-01

    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. Conventional single-junction semiconductor solar cells only effectively convert photons of energy close to the semiconductor band gap (Eg) as a result of the mismatch between the incident solar spectrum and the spectral absorption properties...

  9. Semiconductor-nanocrystal/conjugated polymer thin films

    Science.gov (United States)

    Alivisatos, A. Paul; Dittmer, Janke J.; Huynh, Wendy U.; Milliron, Delia

    2014-06-17

    The invention described herein provides for thin films and methods of making comprising inorganic semiconductor-nanocrystals dispersed in semiconducting-polymers in high loading amounts. The invention also describes photovoltaic devices incorporating the thin films.

  10. Ultrasensitive NO2 Sensor Based on Ohmic Metal-Semiconductor Interfaces of Electrolytically Exfoliated Graphene/Flame-Spray-Made SnO2 Nanoparticles Composite Operating at Low Temperatures.

    Science.gov (United States)

    Tammanoon, Nantikan; Wisitsoraat, Anurat; Sriprachuabwong, Chakrit; Phokharatkul, Ditsayut; Tuantranont, Adisorn; Phanichphant, Sukon; Liewhiran, Chaikarn

    2015-11-04

    In this work, flame-spray-made undoped SnO2 nanoparticles were loaded with 0.1-5 wt % electrolytically exfoliated graphene and systematically studied for NO2 sensing at low working temperatures. Characterizations by X-ray diffraction, transmission/scanning electron microscopy, and Raman and X-ray photoelectron spectroscopy indicated that high-quality multilayer graphene sheets with low oxygen content were widely distributed within spheriodal nanoparticles having polycrystalline tetragonal SnO2 phase. The 10-20 μm thick sensing films fabricated by spin coating on Au/Al2O3 substrates were tested toward NO2 at operating temperatures ranging from 25 to 350 °C in dry air. Gas-sensing results showed that the optimal graphene loading level of 0.5 wt % provided an ultrahigh response of 26,342 toward 5 ppm of NO2 with a short response time of 13 s and good recovery stabilization at a low optimal operating temperature of 150 °C. In addition, the optimal sensor also displayed high sensor response and relatively short response time of 171 and 7 min toward 5 ppm of NO2 at room temperature (25 °C). Furthermore, the sensors displayed very high NO2 selectivity against H2S, NH3, C2H5OH, H2, and H2O. Detailed mechanisms for the drastic NO2 response enhancement by graphene were proposed on the basis of the formation of graphene-undoped SnO2 ohmic metal-semiconductor junctions and accessible interfaces of graphene-SnO2 nanoparticles. Therefore, the electrolytically exfoliated graphene-loaded FSP-made SnO2 sensor is a highly promising candidate for fast, sensitive, and selective detection of NO2 at low operating temperatures.

  11. Silicon processing for photovoltaics II

    CERN Document Server

    Khattak, CP

    2012-01-01

    The processing of semiconductor silicon for manufacturing low cost photovoltaic products has been a field of increasing activity over the past decade and a number of papers have been published in the technical literature. This volume presents comprehensive, in-depth reviews on some of the key technologies developed for processing silicon for photovoltaic applications. It is complementary to Volume 5 in this series and together they provide the only collection of reviews in silicon photovoltaics available.The volume contains papers on: the effect of introducing grain boundaries in silicon; the

  12. Design of photovoltaic systems

    OpenAIRE

    Laso Martínez, Miguel

    2014-01-01

    Photovoltaic (PV) harvesting of solar energy is based on capturing sunlight and transforming it into electricity. This type of electricity generation does not pollute the environment as much as other types of energy production, that is why nowadays some engineers would like to improve it. To carry out this change we use solar cells made of semiconductor materials (Silicon) in which it is artificially created a permanent electric field. These cells are connected in series or par...

  13. Reflective photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Lentine, Anthony L.; Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Goeke, Ronald S.

    2018-03-06

    A photovoltaic module includes colorized reflective photovoltaic cells that act as pixels. The colorized reflective photovoltaic cells are arranged so that reflections from the photovoltaic cells or pixels visually combine into an image on the photovoltaic module. The colorized photovoltaic cell or pixel is composed of a set of 100 to 256 base color sub-pixel reflective segments or sub-pixels. The color of each pixel is determined by the combination of base color sub-pixels forming the pixel. As a result, each pixel can have a wide variety of colors using a set of base colors, which are created, from sub-pixel reflective segments having standard film thicknesses.

  14. Novel Materials for Photovoltaic Technologies: Preprint

    International Nuclear Information System (INIS)

    Alivisatos, P.; Carter, S.; Ginley, D.; Nozik, A.; Meyer, G.; Rosenthal, S.

    1999-01-01

    While existing photovoltaic technologies continue to advance, there are still many exciting opportunities in the area of novel materials. These opportunities arise because there is a substantial need for reducing the costs associated with the preparation and processing of photovoltaics, and because the theoretically possible photovoltaic efficiencies have yet to be achieved in practical devices. Thus it remains reasonable to continue photovoltaic research activity aimed at entirely new approaches to processing and at entirely new materials as the active media. This group identified three areas for further consideration: (a) Nano/molecular composites and hierarchical structures; (b) Organic semiconductors; and (c) Hot carrier devices

  15. Photoelectronic properties of semiconductors

    CERN Document Server

    Bube, Richard H

    1992-01-01

    The interaction between light and electrons in semiconductors forms the basis for many interesting and practically significant properties. This book examines the fundamental physics underlying this rich complexity of photoelectronic properties of semiconductors, and will familiarise the reader with the relatively simple models that are useful in describing these fundamentals. The basic physics is also illustrated with typical recent examples of experimental data and observations. Following introductory material on the basic concepts, the book moves on to consider a wide range of phenomena, including photoconductivity, recombination effects, photoelectronic methods of defect analysis, photoeffects at grain boundaries, amorphous semiconductors, photovoltaic effects and photoeffects in quantum wells and superlattices. The author is Professor of Materials Science and Electrical Engineering at Stanford University, and has taught this material for many years. He is an experienced author, his earlier books having fo...

  16. Photovoltaic device

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Jason A; Keenihan, James R; Gaston, Ryan S; Kauffmann, Keith L; Langmaid, Joseph A; Lopez, Leonardo; Maak, Kevin D; Mills, Michael E; Ramesh, Narayan; Teli, Samar R

    2017-03-21

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

  17. Photovoltaic device

    Science.gov (United States)

    Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

    2015-06-02

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

  18. Photovoltaic device

    Science.gov (United States)

    Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

    2015-09-01

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device (10) with a multilayered photovoltaic cell assembly (100) and a body portion (200) joined at an interface region (410) and including an intermediate layer (500), at least one interconnecting structural member (1500), relieving feature (2500), unique component geometry, or any combination thereof.

  19. First-principles study of electronic structure of CuSbS{sub 2} and CuSbSe{sub 2} photovoltaic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, T., E-mail: tmaeda@ad.ryukoku.ac.jp; Wada, T.

    2015-05-01

    We studied the features of CuSbS{sub 2} (CAS) and CuSbSe{sub 2} (CASe), two proposed photovoltaic compounds, and clarified their electronic structures by first-principles calculations and compared them to the chalcopyrite-type CuInSe{sub 2} results. For both CAS and CASe, the calculated enthalpies of formation of the chalcostibite phases were considerably lower than those of the chalcopyrite phases. Therefore, we considered that the chalcostibite phase is more stable for CAS and CASe. In their band structure calculated with the HSE06 hybrid functional, the valence band maxima of CAS and CASe were located at the Γ-point, and the conduction band minima were located at the R-point. Their second lowest conduction band was located at the Γ-point, whose energy level nearly equaled the R-point. For CAS (CASe), the partial density of the states shows the character of the Cu 3d and S 3p (Se 4p) orbitals at the top of the valence bands and the Sb 5p and S 3p (Se 4p) orbitals at the bottom of the conduction bands. The conduction bands of CAS and CASe have a p-orbital character (Sb 5p) that differs from the s-orbital character (In 5s) of CuInSe{sub 2}. It is for the reason that CAS and CASe do not have a chalcopyrite structure but a chalcostibite-type structure. The calculated absorption coefficient of CuSbS{sub 2} (10{sup 4}-10{sup 5} cm{sup −1}) is comparable to that of CuInSe{sub 2}. - Highlights: • We studied the features of CuSbS{sub 2} and CuSbSe{sub 2}, newly proposed photovoltaic compounds. • Chalcostibite phase is more stable in CuSbS{sub 2} and CuSbSe{sub 2}. • Band structures of CuSbS{sub 2} and CuSbS{sub 2} were calculated with HSE06 hybrid functional. • Absorption coefficient of chalcostibite-type CuSbS{sub 2} is comparable to that of CuInSe{sub 2}.

  20. Structural properties and sensing performance of high-k Nd2TiO5 thin layer-based electrolyte-insulator-semiconductor for pH detection and urea biosensing.

    Science.gov (United States)

    Pan, Tung-Ming; Lin, Jian-Chi; Wu, Min-Hsien; Lai, Chao-Sung

    2009-05-15

    For high sensitive pH sensing, an electrolyte-insulator-semiconductor (EIS) device with Nd(2)TiO(5) thin layers fabricated on Si substrates by means of reactive sputtering and the subsequent post-deposition annealing (PDA) treatment was proposed. In this work, the effect of thermal annealing (600, 700, 800, and 900 degrees C) on the structural characteristics of Nd(2)TiO(5) thin layer was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy. The observed structural properties were then correlated with the resulting pH sensing performances. For enzymatic field-effect-transistors-based urea biosensing, a hybrid configuration of the proposed Nd(2)TiO(5) thin layer with urease-immobilized alginate film attached was established. Within the experimental conditions investigated, the EIS device with the Nd(2)TiO(5) thin layer annealed at 800 degrees C exhibited a higher pH detection sensitivity of 57.2 mV/pH, a lower hysteresis voltage of 2.33 mV, and a lower drift rate of 1.80 mV/h compared to those at other annealing temperatures. These results are attributed to the formation of a thinner low-k interfacial layer at the oxide/Si interface and the higher surface roughness occurred at this annealing temperature. Furthermore, the presented urea biosensor was also proved to be able to detect urea with good linearity (R(2)=0.99) and reasonable sensitivity of 9.52 mV/mM in the urea concentration range of 3-40 mM. As a whole, the present work has provided some fundamental data for the use of Nd(2)TiO(5) thin layer for EIS-based pH detection and the extended application for biosensing.

  1. Graphene/semiconductor silicon modified BiFeO{sub 3}/indium tin oxide ferroelectric photovoltaic device for transparent self-powered windows

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Surbhi; Medwal, Rohit, E-mail: rohitmedwal@gmail.com; Limbu, Tej B.; Katiyar, Rajesh K.; Pavunny, Shojan P.; Morell, G.; Katiyar, R. S., E-mail: rkatiyar@hpcf.upr.edu [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, P.O. Box 70377, San Juan, Puerto Rico 00936-8377 (United States); Tomar, Monika [Physics Department, Miranda House, University of Delhi, Delhi 110007 (India); Gupta, Vinay [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

    2015-08-10

    We report photovoltaic response of highly transparent graphene/BiFe{sub 0.95}Si{sub 0.05}O{sub 3} (BFSiO)/ITO/glass derived from bottom-up spin coating technique. The device exhibits short-circuit-current (I{sub SC} 0.75 mA) with 1000 fold upsurge and open-circuit-voltage (V{sub OC} ∼ 0.45 V) under standard AM 1.5 illumination through graphene. In combination, I{sub SC} of 0.63 mA and V{sub OC} of 0.35 V for same illumination through ITO, reveals the prospects of harvesting indoor light. Also, crystallographic structure, red shift in band gap, leakage behavior, and ferroelectric characteristics of BFSiO thin films are reported. Reproducible transient response of I{sub SC} and V{sub OC} with quick switching (<100 ms) for 20 consecutive cycles and stability (95%) over test period of 16 weeks signifies high endurance and retentivity, promising for building integrated self-powered windows.

  2. Graphene/semiconductor silicon modified BiFeO3/indium tin oxide ferroelectric photovoltaic device for transparent self-powered windows

    International Nuclear Information System (INIS)

    Gupta, Surbhi; Medwal, Rohit; Limbu, Tej B.; Katiyar, Rajesh K.; Pavunny, Shojan P.; Morell, G.; Katiyar, R. S.; Tomar, Monika; Gupta, Vinay

    2015-01-01

    We report photovoltaic response of highly transparent graphene/BiFe 0.95 Si 0.05 O 3 (BFSiO)/ITO/glass derived from bottom-up spin coating technique. The device exhibits short-circuit-current (I SC 0.75 mA) with 1000 fold upsurge and open-circuit-voltage (V OC  ∼ 0.45 V) under standard AM 1.5 illumination through graphene. In combination, I SC of 0.63 mA and V OC of 0.35 V for same illumination through ITO, reveals the prospects of harvesting indoor light. Also, crystallographic structure, red shift in band gap, leakage behavior, and ferroelectric characteristics of BFSiO thin films are reported. Reproducible transient response of I SC and V OC with quick switching (<100 ms) for 20 consecutive cycles and stability (95%) over test period of 16 weeks signifies high endurance and retentivity, promising for building integrated self-powered windows

  3. Enhancement of charge transport properties of small molecule semiconductors by controlling fluorine substitution and effects on photovoltaic properties of organic solar cells and perovskite solar cells.

    Science.gov (United States)

    Yun, Jae Hoon; Park, Sungmin; Heo, Jin Hyuck; Lee, Hyo-Sang; Yoon, Seongwon; Kang, Jinback; Im, Sang Hyuk; Kim, Hyunjung; Lee, Wonmok; Kim, BongSoo; Ko, Min Jae; Chung, Dae Sung; Son, Hae Jung

    2016-11-01

    We prepared a series of small molecules based on 7,7'-(4,4-bis(2-ethylhexyl)-4 H -silolo[3,2- b :4,5- b ']dithiophene-2,6-diyl)bis(4-(5'-hexyl-[2,2'-bithiophene]-5-yl)benzo[ c ][1,2,5]thiadiazole) with different fluorine substitution patterns ( 0F-4F ). Depending on symmetricity and numbers of fluorine atoms incorporated in the benzo[ c ][1,2,5]thiadiazole unit, they show very different optical and morphological properties in a film. 2F and 4F , which featured symmetric and even-numbered fluorine substitution patterns, display improved molecular packing structures and higher crystalline properties in a film compared with 1F and 3F and thus, 2F achieved the highest OTFT mobility, which is followed by 4F . In the bulk heterojunction solar cell fabricated with PC 71 BM, 2F achieves the highest photovoltaic performance with an 8.14% efficiency and 0F shows the lowest efficiency of 1.28%. Moreover, the planar-type perovskite solar cell (PSC) prepared with 2F as a dopant-free hole transport material shows a high power conversion efficiency of 14.5% due to its high charge transporting properties, which were significantly improved compared with the corresponding PSC device obtained from 0F (8.5%). From the studies, it is demonstrated that low variation in the local dipole moment and the narrow distribution of 2F conformers make intermolecular interactions favorable, which may effectively drive crystal formations in the solid state and thus, higher charge transport properties compared with 1F and 3F .

  4. Low cost and efficient photovoltaic conversion by nanocrystalline solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Graetzel, M. [Institut de Chimie Physique, Ecole Polytechnique Federal de Lausanne (Switzerland)

    1996-09-01

    Solar cells are expected to provide environmentally friendly solutions to the world`s energy supply problem. Learning from the concepts used by green plants we have developed a molecular photovoltaic device whose overall efficiency for AM 1.5 solar light to electricity has already attained 8-11%. The system is based on the sensitization of nanocrystalline oxide films by transition metal charge transfer sensitizers. In analogy to photosynthesis, the new chemical solar cell achieves the separation of the light absorption and charge carrier transport processes. Extraordinary yields for the conversion of incident photons into electric current are obtained, exceeding 90% for transition metal complexes within the wavelength range of their absorption band. The use of molten salt electrolytes together with coordination complexes of ruthenium as sensitizers and adequate sealing technology has endowed these cells with a remarkable stability making practical applications feasible. Seven industrial cooperations are presently involved in the development to bring these cells to the market. The first cells will be applied to supply electric power for consumer electronic devices. The launching of production of several products of this type is imminent and they should be on the market within the next two years. Quite aside from their intrinsic merits as photovoltaic device, the mesoscopic oxide semiconductor films developed in our laboratory offer attractive possibilities for a number of other applications. Thus, the first example of a nanocrystalline rocking chair battery will be demonstrated and its principle briefly discussed.

  5. FY 1996 Report on the results of development of photovoltaic power generation system commercialization technologies. Development of device for producing compound semiconductors for photovoltaic cells (Development of flying tester); 1996 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Taiyo denchiyo kagobutsu handotai seizo sochi kaihatsu - hikoyo shikenki no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The compound semiconductor production process is tested under a microgravity by the space experiment/observation free flier (SFU), to reduce the photovoltaic power generation cost. Described herein are the FY 1996 results. The device is confirmed to work as planned by the full-scale test conducted in FY 1995, when it stood on the orbit and was recovered by the space shuttle STS-72 January, 1996. The recovered SFU-carried devices, including the electrical furnace and related subsystems, were found to normally function, and it was concluded that they could be evaluated and analyzed after the flight. The comprehensive evaluation and analysis of their electrical, mechanical, thermal functions have confirmed that they functioned and showed performance as planned, demonstrating validity of the designs and production procedures. The test samples were taken out of the recovered combined furnace, focus furnace and single-heat furnace for the space environment utilization tests. The other samples had much more uniform compositional distributions than those produced on the ground. (NEDO)

  6. Fiscal 1974 Sunshine Project result report. R and D on photovoltaic power generation system (R and D on 2-6 group compound semiconductor solar cells); 1974 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

    1975-05-31

    This report summarizes the fiscal 1974 research result on 2- 6 group compound semiconductor solar cells. To obtain a probability of the technology for producing photovoltaic power generation systems at a cost less than 1/100 of those by current technology, this research aims at establishment of the pollution-free production technology of the titled solar cells, and development of an innovative photovoltaic power generation system using such solar cells. The research is composed of (1) study on deterioration mechanism, (2) measures against pollution, and (3) basic study on the production system of such semiconductors. In the 1st research, the analysis result showed that deterioration under solar radiation or by short circuit is derived from an increase in resistance around a positive electrode and a decrease around a junction caused by change in Cu{sub 2}S composition due to migration of Cu ions in a Cu{sub 2}S layer by photo current. In the 2nd research, study was made on preventive technology of Cd pollution. In the 3rd research, basic study was made on the production systems of semiconductors such as sintering, chemical separating and vapor-phase growth for cost reduction. (NEDO)

  7. Environmental costs of photovoltaics

    International Nuclear Information System (INIS)

    Hill, R.; Baumann, A.E.

    1993-01-01

    Photovoltaic (PV) systems are almost entirely benign in operation, and potential environmental hazards occur at the production and disposal stages. There are well established methods of monitoring and controlling potential hazards caused by the semiconductor materials used in PV modules such as silicon, copper indium diselenide and cadmium telluride. The main environmental hazards of photovoltaics are connected to the production processes. These processes require an input of energy, and this energy is derived from the standard fuel mix of the nation in which production takes place. The production of PV systems therefore has associated with it, emissions of greenhouse and acidic gases. However, as the new thin film PV technologies come into production, and the scale of production increases, the energy input to PV systems will decrease considerably, with consequent reduction in carbon dioxide emissions, to levels below that of other electricity generating technologies. (Author)

  8. Photovoltaic Cells

    OpenAIRE

    Karolis Kiela

    2012-01-01

    The article deals with an overview of photovoltaic cells that are currently manufactured and those being developed, including one or several p-n junction, organic and dye-sensitized cells using quantum dots. The paper describes the advantages and disadvantages of various photovoltaic cells, identifies the main parameters, explains the main reasons for the losses that may occur in photovoltaic cells and looks at the ways to minimize them.Article in Lithuanian

  9. Routes to Ultrahigh Efficiency Photovoltaic and Photoelectrochemical Devices

    Energy Technology Data Exchange (ETDEWEB)

    Eisler, Carissa; Lloyd, John; Flowers, Cris; Darbe, Sunita; Warmann, Emily; Verlage, Erik; Fountaine, Kate; Hu, Shu; Lewis, Nathan; Atwater, Harry

    2014-10-15

    We discuss ‘full spectrum’ photovoltaic modules that leverage low-cost III-V compound semiconductor cells, efficient optics and unconventional fabrication/assembly methods, and discuss advances in photoelectrochemical water-splitting with high efficiency.

  10. Semiconductor nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Marstein Erik Stensrud

    2003-07-01

    This thesis presents a study of two material systems containing semiconductor nanocrystals, namely porous silicon (PSi) films and germanium (Ge) nanocrystals embedded in silicon dioxide (SiO2) films. The PSi films were made by anodic etching of silicon (Si) substrates in an electrolyte containing hydrofluoric acid. The PSi films were doped with erbium (Er) using two different doping methods. electrochemical doping and doping by immersing the PSi films in a solution containing Er. The resulting Er concentration profiles were investigated using scanning electron microscopy (SEN1) combined with energy dispersive X-ray analysis (EDS). The main subject of the work on PSi presented in this thesis was investigating and comparing these two doping methods. Ge nanocrystals were made by implanting Ge ions into Si02 films that were subsequently annealed. However. nanocrystal formation occurred only for certain sets of processing parameters. The dependence of the microstructure of the Ge implanted Si02 films on the processing parameters were therefore investigated. A range of methods were employed for these investigations, including transmission electron microscopy (TEM) combined with EDS, X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS). The observed structures, ranging from Ge nanocrystals to voids with diameters of several tens of nanometers and Ge rich Si02 films without any nanocrystals is described. A model explaining the void formation is also presented. For certain sets of processing parameters. An accumulation of Ge at the Si-Si02 interface was observed. The effect of this accumulation on the electrical properties of MOS structures made from Ge implanted SiO2 films was investigated using CV-measurements. (Author)

  11. Photovoltaic fibers

    Science.gov (United States)

    Gaudiana, Russell; Eckert, Robert; Cardone, John; Ryan, James; Montello, Alan

    2006-08-01

    It was realized early in the history of Konarka that the ability to produce fibers that generate power from solar energy could be applied to a wide variety of applications where fabrics are utilized currently. These applications include personal items such as jackets, shirts and hats, to architectural uses such as awnings, tents, large covers for cars, trucks and even doomed stadiums, to indoor furnishings such as window blinds, shades and drapes. They may also be used as small fabric patches or fiber bundles for powering or recharging batteries in small sensors. Power generating fabrics for clothing is of particular interest to the military where they would be used in uniforms and body armor where portable power is vital to field operations. In strong sunlight these power generating fabrics could be used as a primary source of energy, or they can be used in either direct sunlight or low light conditions to recharge batteries. Early in 2002, Konarka performed a series of proof-of-concept experiments to demonstrate the feasibility of building a photovoltaic cell using dye-sensitized titania and electrolyte on a metal wire core. The approach taken was based on the sequential coating processes used in making fiber optics, namely, a fiber core, e.g., a metal wire serving as the primary electrode, is passed through a series of vertically aligned coating cups. Each of the cups contains a coating fluid that has a specific function in the photocell. A second wire, used as the counter electrode, is brought into the process prior to entering the final coating cup. The latter contains a photopolymerizable, transparent cladding which hardens when passed through a UV chamber. Upon exiting the UV chamber, the finished PV fiber is spooled. Two hundred of foot lengths of PV fiber have been made using this process. When the fiber is exposed to visible radiation, it generates electrical power. The best efficiency exhibited by these fibers is 6% with an average value in the 4

  12. Manipulating semiconductor colloidal stability through doping.

    Science.gov (United States)

    Fleharty, Mark E; van Swol, Frank; Petsev, Dimiter N

    2014-10-10

    The interface between a doped semiconductor material and electrolyte solution is of considerable fundamental interest, and is relevant to systems of practical importance. Both adjacent domains contain mobile charges, which respond to potential variations. This is exploited to design electronic and optoelectronic sensors, and other enabling semiconductor colloidal materials. We show that the charge mobility in both phases leads to a new type of interaction between semiconductor colloids suspended in aqueous electrolyte solutions. This interaction is due to the electrostatic response of the semiconductor interior to disturbances in the external field upon the approach of two particles. The electrostatic repulsion between two charged colloids is reduced from the one governed by the charged groups present at the particles surfaces. This type of interaction is unique to semiconductor particles and may have a substantial effect on the suspension dynamics and stability.

  13. Photovoltaic cell

    Science.gov (United States)

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  14. Semiconductor statistics

    CERN Document Server

    Blakemore, J S

    1987-01-01

    In-depth exploration of the implications of carrier populations and Fermi energies examines distribution of electrons in energy bands and impurity levels of semiconductors. Also: kinetics of semiconductors containing excess carriers, particularly in terms of trapping, excitation, and recombination.

  15. Organic photovoltaics

    DEFF Research Database (Denmark)

    Demming, Anna; Krebs, Frederik C; Chen, Hongzheng

    2013-01-01

    's supply, even at our increasingly ravenous rate of global energy consumption [1]. But it's not what you have got it's what you do with it. Hence the intense focus on photovoltaic research to find more efficient ways to harness energy from the Sun. Recently much of this research has centred on organic...... solar cells since they offer simple, low-cost, light-weight and large-area flexible photovoltaic structures. This issue with guest editors Frederik C Krebs and Hongzheng Chen focuses on some of the developments at the frontier of organic photovoltaic technology. Improving the power conversion efficiency...... of organic photovoltaic systems, while maintaining the inherent material, economic and fabrication benefits, has absorbed a great deal of research attention in recent years. Here significant progress has been made with reports now of organic photovoltaic devices with efficiencies of around 10%. Yet operating...

  16. Plasmonic Nanocone Arrays as Photoconductive and Photovoltaic Metamaterials

    DEFF Research Database (Denmark)

    Zhukovsky, Sergei; Babicheva, Viktoriia; Evlyuknin, Andrey B.

    2014-01-01

    Photoconductive and photovolta ic properties of metamaterials comprising plasmonic nanocone arrays embedded in a semiconductor matrix are studied. Under uniform plane-wave illumination, directed photocurrent and electromotive force arise ne ar asymmetrically shaped nanocones. The resulting giant...... photogalvanic effect is a plasmonic analogue of the bulk photovoltaic effect in ferroelectrics....

  17. Advances in photovoltaics part 4

    CERN Document Server

    Willeke, Gerhard P

    2015-01-01

    Advances in Photovoltaics: Part Four provides valuable information on the challenges faced during the transformation of our energy supply system to more efficient, renewable energies. The volume discusses the topic from a global perspective, presenting the latest information on photovoltaics, a cornerstone technology. It covers all aspects of this important semiconductor technology, reflecting on the tremendous and dynamic advances that have been made on this topic since 1975, when the first book on solar cells-written by Harold J. Hovel of IBM-was published as volume 11 in the now famous series on Semiconductors and Semimetals. Readers will gain a behind the scenes look at the continuous and rapid scientific development that leads to the necessary price and cost reductions in global industrial mass-production. Written by leading, internationally known experts on his topic Provides an in-depth overview of the current status and perspectives of thin film PV technologies Discusses the challenges faced during th...

  18. Semiconductor physics

    CERN Document Server

    Böer, Karl W

    2018-01-01

    This handbook gives a complete survey of the important topics and results in semiconductor physics. It addresses every fundamental principle and most research topics and areas of application in the field of semiconductor physics. Comprehensive information is provided on crystalline bulk and low-dimensional as well as amporphous semiconductors, including optical, transport, and dynamic properties.

  19. Thermal Change for Photovoltaic Panels and Energy Effects

    OpenAIRE

    İmal, Nazım; Hasar, Şahabettin; Çınar, Harun; Şener, Eralp

    2015-01-01

    Photovoltaic panels (solar cells), they receive photon energy from sunlight, convert them to electrical energy by the semiconductor structural features. Photovoltaic panels produce a voltage, depending on the change of functional sunlight exposure. Produced voltage and determining of provided electrical power, must be dealt with the physical parameters that uses the concepts of light and temperature. In this study, usage of monocrystalline and polycrystalline structured photovoltaic panels el...

  20. Recent developments in photovoltaics

    International Nuclear Information System (INIS)

    Green, M.A.

    2004-01-01

    The photovoltaic market is booming with over 30% per annum compounded growth over the last five years. The government-subsidised urban-residential use of photovoltaics, particularly in Germany and Japan, is driving this sustained growth. Most of the solar cells being supplied to this market are 'first generation' devices based on crystalline or multi-crystalline silicon wafers. 'Second generation' thin-film solar cells based on amorphous silicon/hydrogen alloys or polycrystalline compound semiconductors are starting to appear on the market in increasing volume. Australian contributions in this area are the thin-film polycrystalline silicon-on-glass technology developed by Pacific Solar and the dye sensitised nanocrystalline titanium cells developed by Sustainable Technologies International. In these thin-film approaches, the major material cost component is usually the glass sheet onto which the film is deposited. After reviewing the present state of development of both cell and application technologies, the likely future development of photovoltaics is outlined. (author)

  1. Photovoltaic barometer

    International Nuclear Information System (INIS)

    2014-01-01

    The global solar photovoltaic market enjoyed a strong revival in 2013. Preliminary estimates put it in excess of 37 GWp, compared to 30 GWp in 2012 and 2011. The solar photovoltaic sector led the annual installed capacity ratings for renewable energies, taking worldwide capacity up to 137 GWp by the end of the year which means a 35% year-on-year increase. At global level the high growth markets - China, Japan and America - contrast sharply with the contracting European Union market. The strong recovery of the global photovoltaic market is due to the drop in module prices which in some zones has dropped below the conventional electricity price. In the E.U, in 2013 the photovoltaic electricity reached 80.2 TWh while the capacity connected during this year was 9922.2 MWp. Concerning the capacity connected in 2013 the 2 main contributors in Europe are Germany (3310.0 MWc) and Italy (1462.0 MWc). These 2 countries represent also 68% of the cumulated and connected capacity in Europe. All along the article various charts and tables give the figures of the photovoltaic capacity per inhabitant for each E.U country in 2013, the electricity production from photovoltaic power for each E.U country, and the main photovoltaic module manufacturers in 2013 worldwide reporting production and turnover

  2. Photovoltaic device

    DEFF Research Database (Denmark)

    2011-01-01

    A photovoltaic cell module including a plurality of serially connected photovoltaic cells on a common substrate, each including a first electrode, a printed light-harvesting layer and a printed second electrode, wherein at least one of the electrodes is transparent, and wherein the second electrode...... of a first cell is printed such that it forms an electrical contact with the first electrode of an adjacent second cell without forming an electrical contact with the first electrode of the first cell or the light-harvesting layer of the second cell, and a method of making such photovoltaic cell modules....

  3. Photovoltaic barometer

    International Nuclear Information System (INIS)

    Anon.

    2011-01-01

    The photovoltaic sector is continuing on track, just as the extent of solar energy's electricity-generating potential is dawning on the public mind. The annual global installation figure was up more than twofold in 2010 (rising from just short of 7000 MWp in 2009). It leapt to over 16000 MWp, bringing worldwide installed photovoltaic capacity close to 38000 MWp. The photovoltaic power generated in the European Union at the end of 2010 reached 22.5 TWh which means an additional capacity of 13023 MWp during 2010. Concerning the cumulated installed capacity, Germany and Spain rank first and second in the European Union with respectively 17370 MWp and 3808 MWp

  4. Photovoltaic barometer

    International Nuclear Information System (INIS)

    2006-01-01

    This annual evaluation is a synthesis of works published in 2006. Comparisons are presented between the wind power performances and European Commission White Paper and Biomass action plan objectives. The european Union photovoltaic market reached the limits of the sector supply capacity for the first time. Meanwhile the prospects of growth in the photovoltaic market are still just as good as before. Silicon producers have finally responded to the expectations of the photovoltaic industry by announcing new production capacities. These extensions led to massively investing in new production capacities, in phase with ever greater demand. This increase in demand remains, however dependent upon the energy policy. (A.L.B.)

  5. Quantum dot doped solid polymer electrolyte for device application

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Pramod K.; Kim, Kang Wook; Rhee, Hee-Woo [Department of Chemical and Biomolecular Engineering, Sogang University, Mapo-Gu, Seoul 121-742 (Korea)

    2009-06-15

    ZnS capped CdSe quantum dots embedded in PEO:KI:I{sub 2} polymer electrolyte matrix have been synthesized and characterized for dye sensitized solar cell (DSSC) application. The complex impedance spectroscopy shows enhance in ionic conductivity ({sigma}) due to charges provide by quantum dots (QD) while AFM affirm the uniform distribution of QD into polymer electrolyte matrix. Cyclic voltammetry revealed the possible interaction between polymer electrolyte, QD and iodide/iodine. The photovoltaic performances of the DSSC containing quantum dots doped polymer electrolyte was also found to improve. (author)

  6. Photovoltaic barometer

    International Nuclear Information System (INIS)

    2013-01-01

    After the euphoria of 2011, the European Union's photovoltaic market slowed right down in 2012. EurObserv'ER puts newly connected capacity in 2012 at 16.5 GWp compared to 22 GWp in 2011, which is a 25% drop. At global level the market generally held up, with just over 30 GWp installed, bolstered by the build-up of the American and Asian markets. The photovoltaic electricity generated in the EU reached 68.1 TWh in 2012. The article begins with the description of the worldwide situation of photovoltaic electricity, then details the situation for each EU member with the help of tables and charts and ends with the state of photovoltaic industry at the world scale

  7. Photovoltaic barometer

    International Nuclear Information System (INIS)

    Anon.

    2009-01-01

    spain and Germany set the pace for the world photovoltaic market in 2008, which grew to more than twice its 2007 size. The European Union continued to drive photocell installation with an additional 4 592.3 MWp in 2008, or 151.6% growth over 2007. However, European growth prospects for the photovoltaic market in 2009 are being dampened by the global financial crisis and the scheduled slow-down of the Spanish market. (author)

  8. Photovoltaic technologies

    OpenAIRE

    Bagnall, Darren M; Boreland, Matt

    2008-01-01

    Photovoltaics is already a billion dollar industry. It is experiencing rapid growth as concerns over fuel supplies and carbon emissions mean that governments and individuals are increasingly prepared to ignore its current high costs. It will become truly mainstream when its costs are comparable to other energy sources. At the moment, it is around four times too expensive for competitive commercial production. Three generations of photovoltaics have been envisaged that will take solar power in...

  9. Photovoltaic applications

    International Nuclear Information System (INIS)

    Sidrach, M.

    1992-01-01

    The most common terrestrial applications of photovoltaic plants are reviewed. Classification of applications can be done considering end-use sectors and load profiles (consumption demand). For those systems with direct coupling the working point is determined by the intersection of the load line with the I-V curve Design guidelines are provided for photovoltaic systems. This lecture focusses on the distribution system and safeguards

  10. Solid electrolytes

    Science.gov (United States)

    Abraham, Kuzhikalail M.; Alamgir, Mohamed

    1993-06-15

    This invention pertains to Li ion (Li.sup.+) conductive solid polymer electrolytes composed of solvates of Li salts immobilized (encapsulated) in a solid organic polymer matrix. In particular, this invention relates to solid polymer electrolytes derived by immobilizing complexes (solvates) formed between a Li salt such as LiAsF.sub.6, LiCF.sub.3 SO.sub.3 or LiClO.sub.4 and a mixture of aprotic organic solvents having high dielectric constants such as ethylene carbonate (EC) (dielectric constant=89.6) and propylene carbonate (PC) (dielectric constant=64.4) in a polymer matrix such as polyacrylonitrile, poly(tetraethylene glycol diacrylate), or poly(vinyl pyrrolidinone).

  11. Strain sensitivity of band gaps of Sn-containing semiconductors

    DEFF Research Database (Denmark)

    Li, Hong; Castelli, Ivano Eligio; Thygesen, Kristian Sommer

    2015-01-01

    Tuning of band gaps of semiconductors is a way to optimize materials for applications within photovoltaics or as photocatalysts. One way to achieve this is through applying strain to the materials. We investigate the effect of strain on a range of Sn-containing semiconductors using density...

  12. Process Development for Nanostructured Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Elam, Jeffrey W.

    2015-01-01

    Photovoltaic manufacturing is an emerging industry that promises a carbon-free, nearly limitless source of energy for our nation. However, the high-temperature manufacturing processes used for conventional silicon-based photovoltaics are extremely energy-intensive and expensive. This high cost imposes a critical barrier to the widespread implementation of photovoltaic technology. Argonne National Laboratory and its partners recently invented new methods for manufacturing nanostructured photovoltaic devices that allow dramatic savings in materials, process energy, and cost. These methods are based on atomic layer deposition, a thin film synthesis technique that has been commercialized for the mass production of semiconductor microelectronics. The goal of this project was to develop these low-cost fabrication methods for the high efficiency production of nanostructured photovoltaics, and to demonstrate these methods in solar cell manufacturing. We achieved this goal in two ways: 1) we demonstrated the benefits of these coatings in the laboratory by scaling-up the fabrication of low-cost dye sensitized solar cells; 2) we used our coating technology to reduce the manufacturing cost of solar cells under development by our industrial partners.

  13. Combinatorial Discovery and Optimization of the Composition, Doping and Morphology of New Oxide Semiconductors for Efficient Photoelectrochemical Water Splitting

    Energy Technology Data Exchange (ETDEWEB)

    Parkinson, Bruce A. [Univ. of Wyoming, Laramie, WY (United States); Jianghua, He [Univ. of Wyoming, Laramie, WY (United States)

    2015-01-06

    The increasing need for carbon free energy has focused renewed attention on solar energy conversion. Although photovoltaic cells excel at directly converting of solar energy to electricity, they do not directly produce stored energy or fuels that account for more than 75% of current energy use. Direct photoelectrolysis of water has the advantage of converting solar energy directly to hydrogen, an ideal non-carbon and nonpolluting energy carrier, by replacing both a photovoltaic array and an electrolysis unit with one potentially inexpensive device. Unfortunately no materials are currently known to efficiently photoelectrolyze water that are, efficient, inexpensive and stable under illumination in electrolytes for many years. Nanostructured semiconducting metal oxides could potentially fulfill these requirements, making them the most promising materials for solar water photoelectrolysis, however no oxide semiconductor has yet been discovered with all the required properties. We have developed a simple, high-throughput combinatorial approach to prepare and screen many multi component metal oxides for water photoelectrolysis activity. The approach uses ink jet printing of overlapping patterns of soluble metal oxide precursors onto conductive glass substrates. Subsequent pyrolysis produces metal oxide phases that are screened for photoelectrolysis activity by measuring photocurrents produced by scanning a laser over the printed patterns in aqueous electrolytes. Several promising and unexpected compositions have been identified.

  14. Auto-combustion Synthesis, Characterization and Photovoltaic

    African Journals Online (AJOL)

    NICOLAAS

    Ag-NiTiO3, sol-gel method, semiconductor, photovoltaic, doping. 1. Introduction ... convenient for synthesis of pure mixed metal oxides nanoparticles. Furthermore .... current density voltage (I-V) curve for Ag-NiTiO3 was carried out under the ...

  15. Thiophene-Based Organic Semiconductors.

    Science.gov (United States)

    Turkoglu, Gulsen; Cinar, M Emin; Ozturk, Turan

    2017-10-24

    Thiophene-based π-conjugated organic small molecules and polymers are the research subject of significant current interest owing to their potential use as organic semiconductors in material chemistry. Despite simple and similar molecular structures, the hitherto reported properties of thiophene-based organic semiconductors are rather diverse. Design of high performance organic semiconducting materials requires a thorough understanding of inter- and intra-molecular interactions, solid-state packing, and the influence of both factors on the charge carrier transport. In this chapter, thiophene-based organic semiconductors, which are classified in terms of their chemical structures and their structure-property relationships, are addressed for the potential applications as organic photovoltaics (OPVs), organic field-effect transistors (OFETs) and organic light emitting diodes (OLEDs).

  16. Magnesia nanoparticles in liquid electrolyte for dye sensitized solar cells: An effective recombination suppressant?

    International Nuclear Information System (INIS)

    Mohanty, Shyama Prasad; Bhargava, Parag

    2013-01-01

    Highlights: ► MgO loaded electrolyte retards recombination at titania/electrolyte interface. ► Recombination reactions are retarded by adsorption of anions on MgO in electrolyte. ► Zeta potential measurements show anionic adsorption on the surface of MgO. ► MgO loaded electrolyte performs efficiently than TBP containing electrolyte. -- Abstract: Recombination reactions at the photoanode/electrolyte interface reduce the photovoltaic conversion efficiency of dye sensitized solar cells (DSSCs). Unlike modification of titania photoanode by coating with MgO which act as a barrier layer toward recombination, addition of MgO nanopowder to electrolyte prevents recombination through adsorption of anions (triiodide/iodide) from electrolyte. In the present study, the surface charge of MgO has been utilized to adsorb anions from electrolyte. This anionic adsorption onto the MgO nanopowders in electrolyte has been confirmed by zeta potential measurements. MgO retards the recombination reaction as efficiently as 4-tert-butylpyridine (TBP) which is the most widely used additive in the electrolyte. Higher photocurrent and conversion efficiency is achieved by using MgO loaded electrolyte as compared to TBP added electrolyte. Dark current measurements show that recombination reactions are effectively retarded by use of MgO loaded electrolytes. Open circuit voltage decay measurements also confirm higher electron lifetime at the titania/electrolyte interface in MgO loaded electrolyte based cell as compared to additive free electrolyte based cell

  17. Architectures for Improved Organic Semiconductor Devices

    Science.gov (United States)

    Beck, Jonathan H.

    Advancements in the microelectronics industry have brought increasing performance and decreasing prices to a wide range of users. Conventional silicon-based electronics have followed Moore's law to provide an ever-increasing integrated circuit transistor density, which drives processing power, solid-state memory density, and sensor technologies. As shrinking conventional integrated circuits became more challenging, researchers began exploring electronics with the potential to penetrate new applications with a low price of entry: "Electronics everywhere." The new generation of electronics is thin, light, flexible, and inexpensive. Organic electronics are part of the new generation of thin-film electronics, relying on the synthetic flexibility of carbon molecules to create organic semiconductors, absorbers, and emitters which perform useful tasks. Organic electronics can be fabricated with low energy input on a variety of novel substrates, including inexpensive plastic sheets. The potential ease of synthesis and fabrication of organic-based devices means that organic electronics can be made at very low cost. Successfully demonstrated organic semiconductor devices include photovoltaics, photodetectors, transistors, and light emitting diodes. Several challenges that face organic semiconductor devices are low performance relative to conventional devices, long-term device stability, and development of new organic-compatible processes and materials. While the absorption and emission performance of organic materials in photovoltaics and light emitting diodes is extraordinarily high for thin films, the charge conduction mobilities are generally low. Building highly efficient devices with low-mobility materials is one challenge. Many organic semiconductor films are unstable during fabrication, storage, and operation due to reactions with water, oxygen and hydroxide. A final challenge facing organic electronics is the need for new processes and materials for electrodes

  18. Concentrator Photovoltaics

    CERN Document Server

    Luque, Antonio L

    2007-01-01

    Photovoltaic solar-energy conversion is one of the most promising technologies for generating renewable energy, and conversion of concentrated sunlight can lead to reduced cost for solar electricity. In fact, photovoltaic conversion of concentrated sunlight insures an efficient and cost-effective sustainable power resource. This book gives an overview of all components, e.g. cells, concentrators, modules and systems, for systems of concentrator photovoltaics. The authors report on significant results related to design, technology, and applications, and also cover the fundamental physics and market considerations. Specific contributions include: theory and practice of sunlight concentrators; an overview of concentrator PV activities; a description of concentrator solar cells; design and technology of modules and systems; manufacturing aspects; and a market study.

  19. Device Physics of Narrow Gap Semiconductors

    CERN Document Server

    Chu, Junhao

    2010-01-01

    Narrow gap semiconductors obey the general rules of semiconductor science, but often exhibit extreme features of these rules because of the same properties that produce their narrow gaps. Consequently these materials provide sensitive tests of theory, and the opportunity for the design of innovative devices. Narrow gap semiconductors are the most important materials for the preparation of advanced modern infrared systems. Device Physics of Narrow Gap Semiconductors offers descriptions of the materials science and device physics of these unique materials. Topics covered include impurities and defects, recombination mechanisms, surface and interface properties, and the properties of low dimensional systems for infrared applications. This book will help readers to understand not only the semiconductor physics and materials science, but also how they relate to advanced opto-electronic devices. The last chapter applies the understanding of device physics to photoconductive detectors, photovoltaic infrared detector...

  20. Molecular semiconductors photoelectrical properties and solar cells

    CERN Document Server

    Rees, Ch

    1985-01-01

    During the past thirty years considerable efforts have been made to design the synthesis and the study of molecular semiconductors. Molecular semiconductors - and more generally molecular materials - involve interactions between individual subunits which can be separately synthesized. Organic and metallo-organic derivatives are the basis of most of the molecular materials. A survey of the literature on molecular semiconductors leaves one rather confused. It does seem to be very difficult to correlate the molecular structure of these semiconductors with their experimental electrical properties. For inorganic materials a simple definition delimits a fairly homogeneous family. If an inorganic material has a conductivity intermediate between that of an 12 1 1 3 1 1 insulator « 10- n- cm- ) and that of a metal (> 10 n- cm- ), then it is a semiconductor and will exhibit the characteristic properties of this family, such as junction formation, photoconductivity, and the photovoltaic effect. For molecular compounds,...

  1. Photovoltaics Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-02-01

    This fact sheet is an overview of the Photovoltaics (PV) subprogram at the U.S. Department of Energy SunShot Initiative. The U.S. Department of Energy (DOE)’s Solar Energy Technologies Office works with industry, academia, national laboratories, and other government agencies to advance solar PV, which is the direct conversion of sunlight into electricity by a semiconductor, in support of the goals of the SunShot Initiative. SunShot supports research and development to aggressively advance PV technology by improving efficiency and reliability and lowering manufacturing costs. SunShot’s PV portfolio spans work from early-stage solar cell research through technology commercialization, including work on materials, processes, and device structure and characterization techniques.

  2. Photovoltaic spectral responsivity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Emery, K.; Dunlavy, D.; Field, H.; Moriarty, T. [National Renewable Energy Lab., Golden, CO (United States)

    1998-09-01

    This paper discusses the various elemental random and nonrandom error sources in typical spectral responsivity measurement systems. The authors focus specifically on the filter and grating monochrometer-based spectral responsivity measurement systems used by the Photovoltaic (PV) performance characterization team at NREL. A variety of subtle measurement errors can occur that arise from a finite photo-current response time, bandwidth of the monochromatic light, waveform of the monochromatic light, and spatial uniformity of the monochromatic and bias lights; the errors depend on the light source, PV technology, and measurement system. The quantum efficiency can be a function of he voltage bias, light bias level, and, for some structures, the spectral content of the bias light or location on the PV device. This paper compares the advantages and problems associated with semiconductor-detector-based calibrations and pyroelectric-detector-based calibrations. Different current-to-voltage conversion and ac photo-current detection strategies employed at NREL are compared and contrasted.

  3. Applied photovoltaics

    CERN Document Server

    Wenham, Stuart R; Watt, Muriel E; Corkish, Richard; Sproul, Alistair

    2013-01-01

    The new edition of this thoroughly considered textbook provides a reliable, accessible and comprehensive guide for students of photovoltaic applications and renewable energy engineering. Written by a group of award-winning authors it is brimming with information and is carefully designed to meet the needs of its readers. Along with exercises and references at the end of each chapter, it features a set of detailed technical appendices that provide essential equations, data sources and standards. The new edition has been fully updated with the latest information on photovoltaic cells,

  4. Solid State Polymer Electrolytes for Dye-sensitized Solar Cell

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    1 Introduction Over the past decade,Dye-sensitized solar cells (DSSCs) have been intensively investigated as potential alternatives to conventional inorganic photovoltaic devices due to their low production cost and high energy conversion[1-4]. This type of solar cell has achieved an impressive energy conversion efficiency of over 10%,whose electrolyte is a voltaic organic liquid solvent containing iodide/triiodide as redox couple.However,the use of a liquid electrolyte brings difficulties in the practi...

  5. Vacuum-Ultraviolet Photovoltaic Detector.

    Science.gov (United States)

    Zheng, Wei; Lin, Richeng; Ran, Junxue; Zhang, Zhaojun; Ji, Xu; Huang, Feng

    2018-01-23

    Over the past two decades, solar- and astrophysicists and material scientists have been researching and developing new-generation semiconductor-based vacuum ultraviolet (VUV) detectors with low power consumption and small size for replacing traditional heavy and high-energy-consuming microchannel-detection systems, to study the formation and evolution of stars. However, the most desirable semiconductor-based VUV photovoltaic detector capable of achieving zero power consumption has not yet been achieved. With high-crystallinity multistep epitaxial grown AlN as a VUV-absorbing layer for photogenerated carriers and p-type graphene (with unexpected VUV transmittance >96%) as a transparent electrode to collect excited holes, we constructed a heterojunction device with photovoltaic detection for VUV light. The device exhibits an encouraging VUV photoresponse, high external quantum efficiency (EQE) and extremely fast tempera response (80 ns, 10 4 -10 6 times faster than that of the currently reported VUV photoconductive devices). This work has provided an idea for developing zero power consumption and integrated VUV photovoltaic detectors with ultrafast and high-sensitivity VUV detection capability, which not only allows future spacecraft to operate with longer service time and lower launching cost but also ensures an ultrafast evolution of interstellar objects.

  6. Doping of organic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Luessem, B.; Riede, M.; Leo, K. [Institut fuer Angewandte Photophysik, TU Dresden (Germany)

    2013-01-15

    The understanding and applications of organic semiconductors have shown remarkable progress in recent years. This material class has been developed from being a lab curiosity to the basis of first successful products as small organic LED (OLED) displays; other areas of application such as OLED lighting and organic photovoltaics are on the verge of broad commercialization. Organic semiconductors are superior to inorganic ones for low-cost and large-area optoelectronics due to their flexibility, easy deposition, and broad variety, making tailor-made materials possible. However, electrical doping of organic semiconductors, i.e. the controlled adjustment of Fermi level that has been extremely important to the success of inorganic semiconductors, is still in its infancy. This review will discuss recent work on both fundamental principles and applications of doping, focused primarily to doping of evaporated organic layers with molecular dopants. Recently, both p- and n-type molecular dopants have been developed that lead to efficient and stable doping of organic thin films. Due to doping, the conductivity of the doped layers increases several orders of magnitude and allows for quasi-Ohmic contacts between organic layers and metal electrodes. Besides reducing voltage losses, doping thus also gives design freedom in terms of transport layer thickness and electrode choice. The use of doping in applications like OLEDs and organic solar cells is highlighted in this review. Overall, controlled molecular doping can be considered as key enabling technology for many different organic device types that can lead to significant improvements in efficiencies and lifetimes. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Doping of organic semiconductors

    International Nuclear Information System (INIS)

    Luessem, B.; Riede, M.; Leo, K.

    2013-01-01

    The understanding and applications of organic semiconductors have shown remarkable progress in recent years. This material class has been developed from being a lab curiosity to the basis of first successful products as small organic LED (OLED) displays; other areas of application such as OLED lighting and organic photovoltaics are on the verge of broad commercialization. Organic semiconductors are superior to inorganic ones for low-cost and large-area optoelectronics due to their flexibility, easy deposition, and broad variety, making tailor-made materials possible. However, electrical doping of organic semiconductors, i.e. the controlled adjustment of Fermi level that has been extremely important to the success of inorganic semiconductors, is still in its infancy. This review will discuss recent work on both fundamental principles and applications of doping, focused primarily to doping of evaporated organic layers with molecular dopants. Recently, both p- and n-type molecular dopants have been developed that lead to efficient and stable doping of organic thin films. Due to doping, the conductivity of the doped layers increases several orders of magnitude and allows for quasi-Ohmic contacts between organic layers and metal electrodes. Besides reducing voltage losses, doping thus also gives design freedom in terms of transport layer thickness and electrode choice. The use of doping in applications like OLEDs and organic solar cells is highlighted in this review. Overall, controlled molecular doping can be considered as key enabling technology for many different organic device types that can lead to significant improvements in efficiencies and lifetimes. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Semiconductor Manufacturing equipment introduction

    International Nuclear Information System (INIS)

    Im, Jong Sun

    2001-02-01

    This book deals with semiconductor manufacturing equipment. It is comprised of nine chapters, which are manufacturing process of semiconductor device, history of semiconductor manufacturing equipment, kinds and role of semiconductor manufacturing equipment, construction and method of semiconductor manufacturing equipment, introduction of various semiconductor manufacturing equipment, spots of semiconductor manufacturing, technical elements of semiconductor manufacturing equipment, road map of technology of semiconductor manufacturing equipment and semiconductor manufacturing equipment in the 21st century.

  9. Semiconductor spintronics

    CERN Document Server

    Xia, Jianbai; Chang, Kai

    2012-01-01

    Semiconductor Spintronics, as an emerging research discipline and an important advanced field in physics, has developed quickly and obtained fruitful results in recent decades. This volume is the first monograph summarizing the physical foundation and the experimental results obtained in this field. With the culmination of the authors' extensive working experiences, this book presents the developing history of semiconductor spintronics, its basic concepts and theories, experimental results, and the prospected future development. This unique book intends to provide a systematic and modern foundation for semiconductor spintronics aimed at researchers, professors, post-doctorates, and graduate students, and to help them master the overall knowledge of spintronics.

  10. Methods of producing free-standing semiconductors using sacrificial buffer layers and recyclable substrates

    Science.gov (United States)

    Ptak, Aaron Joseph; Lin, Yong; Norman, Andrew; Alberi, Kirstin

    2015-05-26

    A method of producing semiconductor materials and devices that incorporate the semiconductor materials are provided. In particular, a method is provided of producing a semiconductor material, such as a III-V semiconductor, on a spinel substrate using a sacrificial buffer layer, and devices such as photovoltaic cells that incorporate the semiconductor materials. The sacrificial buffer material and semiconductor materials may be deposited using lattice-matching epitaxy or coincident site lattice-matching epitaxy, resulting in a close degree of lattice matching between the substrate material and deposited material for a wide variety of material compositions. The sacrificial buffer layer may be dissolved using an epitaxial liftoff technique in order to separate the semiconductor device from the spinel substrate, and the spinel substrate may be reused in the subsequent fabrication of other semiconductor devices. The low-defect density semiconductor materials produced using this method result in the enhanced performance of the semiconductor devices that incorporate the semiconductor materials.

  11. Advances in photovoltaics pt.3

    CERN Document Server

    Willeke, Gerhard P

    2014-01-01

    This volume is the third of a set of seven on the topic of photovoltaics. Solar cell-related technologies covered here include: ribbon silicon; heterojunction crystalline silicon; wafer equivalent crystalline silicon; and other advanced silicon solar cell structures and processes. Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. Originally widely known as the ""Willardson and Beer"" Series, it has succeeded in publishing numerous landmark volumes and chapters. The series publishes timely, highly relevant v

  12. Semiconductor spintronics

    International Nuclear Information System (INIS)

    Fabian, J.; Abiague, A.M.; Ertler, Ch.; Stano, P.; Zutic, I.

    2007-01-01

    Spintronics refers commonly to phenomena in which the spin of electrons in a solid state environment plays the determining role. In a more narrow sense spintronics is an emerging research field of electronics: spintronics devices are based on a spin control of electronics, or on an electrical and optical control of spin of magnetism. While metal spintronics has already found its niche in the computer industry - giant magnetoresistance systems are used as hard disk read heads - semiconductor spintronics is vet demonstrate its full potential. This review presents selected themes of semiconductor spintronics, introducing important concepts in spin transport, spin transport, spin injection. Silsbee-Johnson spin-charge coupling, and spin-dependent tunneling, as well as spin relaxation and spin dynamics. The most fundamental spin-dependent interaction in nonmagnetic semiconductors is spin-orbit coupling. Depending on the crystal symmetries of the material, as well as on the structural properties of semiconductor based heterostructures, the spin-orbit coupling takes on different functional forms, giving a nice playground of effective spin-orbit Hamiltonians. The effective Hamiltonians for the most relevant classes of materials and heterostructures are derived here from realistic electronic band structure descriptions. Most semiconductor device systems are still theoretical concepts, waiting for experimental demonstrations. A review of selected proposed, and a few demonstrated devices is presented, with detailed description of two important classes: magnetic resonant tunnel structures and bipolar magnetic diodes and transistors. In view of the importance of ferromagnetic semiconductor material, a brief discussion of diluted magnetic semiconductors is included. In most cases the presentation is of tutorial style, introducing the essential theoretical formalism at an accessible level, with case-study-like illustrations of actual experimental results, as well as with brief

  13. Preliminary study of application of Moringa oleifera resin as polymer electrolyte in DSSC solar cells

    Science.gov (United States)

    Saehana, Sahrul; Darsikin, Muslimin

    2016-04-01

    This study reports the preliminary study of application of Moringa oleifera resin as polymer electrolyte in dye-sensitized solar cell (DSSC). We found that polymer electrolyte membrane was formed by using solution casting methods. It is observed that polymer electrolyte was in elastic form and it is very potential to application as DSSC component. Performance of DSSC which employing Moringa oleifera resin was also observed and photovoltaic effect was found.

  14. Method for depositing high-quality microcrystalline semiconductor materials

    Science.gov (United States)

    Guha, Subhendu [Bloomfield Hills, MI; Yang, Chi C [Troy, MI; Yan, Baojie [Rochester Hills, MI

    2011-03-08

    A process for the plasma deposition of a layer of a microcrystalline semiconductor material is carried out by energizing a process gas which includes a precursor of the semiconductor material and a diluent with electromagnetic energy so as to create a plasma therefrom. The plasma deposits a layer of the microcrystalline semiconductor material onto the substrate. The concentration of the diluent in the process gas is varied as a function of the thickness of the layer of microcrystalline semiconductor material which has been deposited. Also disclosed is the use of the process for the preparation of an N-I-P type photovoltaic device.

  15. Thermotropic Phase Transition of Benzodithiophene Copolymer Thin Films and Its Impact on Electrical and Photovoltaic Characteristics

    KAUST Repository

    Ko, Sangwon; Kim, Do Hwan; Ayzner, Alexander L.; Mannsfeld, Stefan C. B.; Verploegen, Eric; Nardes, Alexander M.; Kopidakis, Nikos; Toney, Michael F.; Bao, Zhenan

    2015-01-01

    ) and a decreased LD upon annealing. This study provides insight into the dependence of charge transport and photovoltaic characteristics on molecular packing in polymer semiconductors, which is crucial for the management of charge and energy transport

  16. Structural correlations in the generation of polaron pairs in low-bandgap polymers for photovoltaics

    NARCIS (Netherlands)

    Tautz, Raphael; Da Como, Enrico; Limmer, Thomas; Feldmann, Jochen; Egelhaaf, Hans-Joachim; von Hauff, Elizabeth; Lemaur, Vincent; Beljonne, David; Yilmaz, Seyfullah; Dumsch, Ines; Allard, Sybille; Scherf, Ullrich

    Polymeric semiconductors are materials where unique optical and electronic properties often originate from a tailored chemical structure. This allows for synthesizing conjugated macromolecules with ad hoc functionalities for organic electronics. In photovoltaics, donor–acceptor co-polymers, with

  17. Roof Photovoltaic Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — In order to accurately predict the annual energy production of photovoltaic systems for any given geographical location, building orientation, and photovoltaic cell...

  18. Photovoltaic Wire, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will investigate a new architecture for photovoltaic devices based on nanotechnology: photovoltaic wire. The...

  19. DNA Based Electrochromic and Photovoltaic Cells

    Science.gov (United States)

    2012-01-01

    using deoxyribonucleic acid complex as an electron blocking layer App. Phys. Lett. 88 (2006) 171109. 23. F.H.C. Crick , J.D. Watson . The complementary...9550-09-1-0647 final 01-09-2009 ; 30-11-2011 DNA Based Electrochromic and Photovoltaic Cells FA 9550-09-1-0647 Pawlicka, Agnieszka, J. Instituto de...Available. DNA is an abundant natural product with very good biodegradation properties and can be used to obtain gel polymer electrolytes (GPEs) with high

  20. Photovoltaic module and laminate

    Science.gov (United States)

    Bunea, Gabriela E.; Kim, Sung Dug; Kavulak, David F.J.

    2018-04-10

    A photovoltaic module is disclosed. The photovoltaic module has a first side directed toward the sun during normal operation and a second, lower side. The photovoltaic module comprises a perimeter frame and a photovoltaic laminate at least partially enclosed by and supported by the perimeter frame. The photovoltaic laminate comprises a transparent cover layer positioned toward the first side of the photovoltaic module, an upper encapsulant layer beneath and adhering to the cover layer, a plurality of photovoltaic solar cells beneath the upper encapsulant layer, the photovoltaic solar cells electrically interconnected, a lower encapsulant layer beneath the plurality of photovoltaic solar cells, the upper and lower encapsulant layers enclosing the plurality of photovoltaic solar cells, and a homogenous rear environmental protection layer, the rear environmental protection layer adhering to the lower encapsulant layer, the rear environmental protection layer exposed to the ambient environment on the second side of the photovoltaic module.

  1. Oxide semiconductors

    CERN Document Server

    Svensson, Bengt G; Jagadish, Chennupati

    2013-01-01

    Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. Originally widely known as the ""Willardson and Beer"" Series, it has succeeded in publishing numerous landmark volumes and chapters. The series publishes timely, highly relevant volumes intended for long-term impact and reflecting the truly interdisciplinary nature of the field. The volumes in Semiconductors and Semimetals have been and will continue to be of great interest to physicists, chemists, materials scientists, and device engineers in academia, scient

  2. Semiconductor statistics

    CERN Document Server

    Blakemore, J S

    1962-01-01

    Semiconductor Statistics presents statistics aimed at complementing existing books on the relationships between carrier densities and transport effects. The book is divided into two parts. Part I provides introductory material on the electron theory of solids, and then discusses carrier statistics for semiconductors in thermal equilibrium. Of course a solid cannot be in true thermodynamic equilibrium if any electrical current is passed; but when currents are reasonably small the distribution function is but little perturbed, and the carrier distribution for such a """"quasi-equilibrium"""" co

  3. Photophysics and electrochemistry relevant to photocatalytic water splitting involved at solid–electrolyte interfaces

    KAUST Repository

    Shinagawa, Tatsuya; Cao, Zhen; Cavallo, Luigi; Takanabe, Kazuhiro

    2016-01-01

    Direct photon to chemical energy conversion using semiconductor-electrocatalyst-electrolyte interfaces has been extensively investigated for more than a half century. Many studies have focused on screening materials for efficient photocatalysis

  4. Manufacture of ribbon and solar cells of material of semiconductor grade

    International Nuclear Information System (INIS)

    1980-01-01

    A method is described of producing ribbon-like substantially monocrystalline bodies of silicon or other materials of semiconductor grade suitable for use in solar cells or other semiconductor devices. A tube of the material is made and a photovoltaic junction formed in it. The tube is then divided lengthwise into a number of ribbon-like bodies. The photovoltaic junction can be formed either by diffusion or by ion-implantation. (U.K.)

  5. Photon and carrier management design for nonplanar thin-film copper indium gallium diselenide photovoltaics

    Science.gov (United States)

    Atwater, Harry A.; Callahan, Dennis; Bukowsky, Colton

    2017-11-21

    Photovoltaic structures are disclosed. The structures can comprise randomly or periodically structured layers, a dielectric layer to reduce back diffusion of charge carriers, and a metallic layer to reflect photons back towards the absorbing semiconductor layers. This design can increase efficiency of photovoltaic structures. The structures can be fabricated by nanoimprint.

  6. Semiconductor Detectors

    International Nuclear Information System (INIS)

    Cortina, E.

    2007-01-01

    Particle detectors based on semiconductor materials are among the few devices used for particle detection that are available to the public at large. In fact we are surrounded by them in our daily lives: they are used in photoelectric cells for opening doors, in digital photographic and video camera, and in bar code readers at supermarket cash registers. (Author)

  7. Organic photovoltaic energy in Japan

    International Nuclear Information System (INIS)

    2007-01-01

    Japan finances research programs on photovoltaic conversion since 1974. Research in this domain is one of the 11 priorities of NEDO, the agency of means of the ministry of economy, trade and industry of Japan. The search for an abatement of production costs and of an increase of cells efficiency is mentioned in NEDO's programs as soon as the beginning of the 1990's. A road map has been defined which foresees photovoltaic energy production costs equivalent to the ones of thermal conversion by 2030, i.e. 7 yen/kWh (4.4 cents of euro/kWh). The use of new materials in dye-sensitized solar cells (DSSC) or organic solar cells, and of new structures (multi-junctions) is explored to reach this objective. The organic photovoltaic technology is more particularly considered for small generation units in mobile or domestic technologies. Japan is particularly in advance in the improvement of DSSC cells efficiency, in particular in the domain of the research on solid electrolytes. Europe seems more in advance in the domain of the new generation of organic solar cells. Therefore, a complementarity may be found between Japan and French teams in the domain of organic solar cells improvement through collaboration programs. (J.S.)

  8. Photovoltaic and photoelectrochemical conversion of solar energy.

    Science.gov (United States)

    Grätzel, Michael

    2007-04-15

    The Sun provides approximately 100,000 terawatts to the Earth which is about 10000 times more than the present rate of the world's present energy consumption. Photovoltaic cells are being increasingly used to tap into this huge resource and will play a key role in future sustainable energy systems. So far, solid-state junction devices, usually made of silicon, crystalline or amorphous, and profiting from the experience and material availability resulting from the semiconductor industry, have dominated photovoltaic solar energy converters. These systems have by now attained a mature state serving a rapidly growing market, expected to rise to 300 GW by 2030. However, the cost of photovoltaic electricity production is still too high to be competitive with nuclear or fossil energy. Thin film photovoltaic cells made of CuInSe or CdTe are being increasingly employed along with amorphous silicon. The recently discovered cells based on mesoscopic inorganic or organic semiconductors commonly referred to as 'bulk' junctions due to their three-dimensional structure are very attractive alternatives which offer the prospect of very low cost fabrication. The prototype of this family of devices is the dye-sensitized solar cell (DSC), which accomplishes the optical absorption and the charge separation processes by the association of a sensitizer as light-absorbing material with a wide band gap semiconductor of mesoporous or nanocrystalline morphology. Research is booming also in the area of third generation photovoltaic cells where multi-junction devices and a recent breakthrough concerning multiple carrier generation in quantum dot absorbers offer promising perspectives.

  9. Temperature and Solar Radiation Effects on Photovoltaic Panel Power

    OpenAIRE

    Karafil, Akif; Ozbay, Harun; Kesler, Metin

    2016-01-01

    Solar energy is converted to electrical energy directly by semi-conductors materials used in Photovoltaic (PV) panels. Although, there has been great advancements in semi-conductor material technology in recent years panel efficiency is very lower. There are many factors affecting the panel efficiency such as tilt angle, shading, dust, solar radiation level, temperature and wiring losses. Among these factors, solar radiation level and temperature are more prominent. The solar radiation level ...

  10. Photovoltaic solar concentrator

    Science.gov (United States)

    Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J.; Sanchez, Carlos Anthony; Clews, Peggy J.; Gupta, Vipin P.

    2015-09-08

    A process including forming a photovoltaic solar cell on a substrate, the photovoltaic solar cell comprising an anchor positioned between the photovoltaic solar cell and the substrate to suspend the photovoltaic solar cell from the substrate. A surface of the photovoltaic solar cell opposite the substrate is attached to a receiving substrate. The receiving substrate may be bonded to the photovoltaic solar cell using an adhesive force or a metal connecting member. The photovoltaic solar cell is then detached from the substrate by lifting the receiving substrate having the photovoltaic solar cell attached thereto and severing the anchor connecting the photovoltaic solar cell to the substrate. Depending upon the type of receiving substrate used, the photovoltaic solar cell may be removed from the receiving substrate or remain on the receiving substrate for use in the final product.

  11. Organic photovoltaics

    Science.gov (United States)

    Demming, Anna; Krebs, Frederik C.; Chen, Hongzheng

    2013-12-01

    Energy inflation, the constant encouragement to economize on energy consumption and the huge investments in developing alternative energy resources might seem to suggest that there is a global shortage of energy. Far from it, the energy the Sun beams on the Earth each hour is equivalent to a year's supply, even at our increasingly ravenous rate of global energy consumption [1]. But it's not what you have got it's what you do with it. Hence the intense focus on photovoltaic research to find more efficient ways to harness energy from the Sun. Recently much of this research has centred on organic solar cells since they offer simple, low-cost, light-weight and large-area flexible photovoltaic structures. This issue with guest editors Frederik C Krebs and Hongzheng Chen focuses on some of the developments at the frontier of organic photovoltaic technology. Improving the power conversion efficiency of organic photovoltaic systems, while maintaining the inherent material, economic and fabrication benefits, has absorbed a great deal of research attention in recent years. Here significant progress has been made with reports now of organic photovoltaic devices with efficiencies of around 10%. Yet operating effectively across the electromagnetic spectrum remains a challenge. 'The trend is towards engineering low bandgap polymers with a wide optical absorption range and efficient hole/electron transport materials, so that light harvesting in the red and infrared region is enhanced and as much light of the solar spectrum as possible can be converted into an electrical current', explains Mukundan Thelakkat and colleagues in Germany, the US and UK. In this special issue they report on how charge carrier mobility and morphology of the active blend layer in thin film organic solar cells correlate with device parameters [2]. The work contributes to a better understanding of the solar-cell characteristics of polymer:fullerene blends, which form the material basis for some of the most

  12. Rational Design of High-Performance Wide-Bandgap (≈2 eV) Polymer Semiconductors as Electron Donors in Organic Photovoltaics Exhibiting High Open Circuit Voltages (≈1 V).

    Science.gov (United States)

    Chochos, Christos L; Katsouras, Athanasios; Gasparini, Nicola; Koulogiannis, Chrysanthos; Ameri, Tayebeh; Brabec, Christoph J; Avgeropoulos, Apostolos

    2017-01-01

    Systematic optimization of the chemical structure of wide-bandgap (≈2.0 eV) "donor-acceptor" copolymers consisting of indacenodithiophene or indacenodithieno[3,2-b]thiophene as the electron-rich unit and thieno[3,4-c]pyrrole-4,6-dione as the electron-deficient moiety in terms of alkyl side chain engineering and distance of the electron-rich and electron-deficient monomers within the repeat unit of the polymer chain results in high-performance electron donor materials for organic photovoltaics. Specifically, preliminary results demonstrate extremely high open circuit voltages (V oc s) of ≈1.0 V, reasonable short circuit current density (J sc ) of around 11 mA cm -2 , and moderate fill factors resulting in efficiencies close to 6%. All the devices are fabricated in an inverted architecture with the photoactive layer processed by doctor blade equipment, showing the compatibility with roll-to-roll large-scale manufacturing processes. From the correlation of the chemical structure-optoelectronic properties-photovoltaic performance, a rational guide toward further optimization of the chemical structure in this family of copolymers, has been achieved. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Semiconductor sensors

    International Nuclear Information System (INIS)

    Hartmann, Frank

    2011-01-01

    Semiconductor sensors have been around since the 1950s and today, every high energy physics experiment has one in its repertoire. In Lepton as well as Hadron colliders, silicon vertex and tracking detectors led to the most amazing physics and will continue doing so in the future. This contribution tries to depict the history of these devices exemplarily without being able to honor all important developments and installations. The current understanding of radiation damage mechanisms and recent R and D topics demonstrating the future challenges and possible technical solutions for the SLHC detectors are presented. Consequently semiconductor sensor candidates for an LHC upgrade and a future linear collider are also briefly introduced. The work presented here is a collage of the work of many individual silicon experts spread over several collaborations across the world.

  14. Semiconductor Optics

    CERN Document Server

    Klingshirn, Claus F

    2012-01-01

    This updated and enlarged new edition of Semiconductor Optics provides an introduction to and an overview of semiconductor optics from the IR through the visible to the UV, including linear and nonlinear optical properties, dynamics, magneto and electrooptics, high-excitation effects and laser processes, some applications, experimental techniques and group theory. The mathematics is kept as elementary as possible, sufficient for an intuitive understanding of the experimental results and techniques treated. The subjects covered extend from physics to materials science and optoelectronics. Significantly updated chapters add coverage of current topics such as electron hole plasma, Bose condensation of excitons and meta materials. Over 120 problems, chapter introductions and a detailed index make it the key textbook for graduate students in physics. The mathematics is kept as elementary as possible, sufficient for an intuitive understanding of the experimental results and techniques treated. The subjects covered ...

  15. Semiconductor annealing

    International Nuclear Information System (INIS)

    Young, J.M.; Scovell, P.D.

    1982-01-01

    A process for annealing crystal damage in ion implanted semiconductor devices in which the device is rapidly heated to a temperature between 450 and 900 0 C and allowed to cool. It has been found that such heating of the device to these relatively low temperatures results in rapid annealing. In one application the device may be heated on a graphite element mounted between electrodes in an inert atmosphere in a chamber. (author)

  16. Nanoporous polymer electrolyte

    Science.gov (United States)

    Elliott, Brian [Wheat Ridge, CO; Nguyen, Vinh [Wheat Ridge, CO

    2012-04-24

    A nanoporous polymer electrolyte and methods for making the polymer electrolyte are disclosed. The polymer electrolyte comprises a crosslinked self-assembly of a polymerizable salt surfactant, wherein the crosslinked self-assembly includes nanopores and wherein the crosslinked self-assembly has a conductivity of at least 1.0.times.10.sup.-6 S/cm at 25.degree. C. The method of making a polymer electrolyte comprises providing a polymerizable salt surfactant. The method further comprises crosslinking the polymerizable salt surfactant to form a nanoporous polymer electrolyte.

  17. Solidification of liquid electrolyte with imidazole polymers for quasi-solid-state dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Wang Miao; Lin Yuan; Zhou Xiaowen; Xiao Xurui; Yang Lei; Feng Shujing; Li Xueping

    2008-01-01

    Quasi-solid-state electrolytes were prepared by employing the imidazole polymers to solidify the liquid electrolyte containing lithium iodide, iodine and ethylene carbonate (EC)/propylene carbonate (PC) mixed solvent. The ionic conductivity and diffusion behavior of triiodide in the quasi-solid-state electrolytes were examined in terms of the polymer content. Application of the quasi-solid-state electrolytes to the dye-sensitized solar cells, the maximum energy conversion efficiency of 7.6% (AM 1.5, 100 mW cm -2 ) was achieved. The dependence of the photovoltaic performance on the polymer content and on the different anions of the imidazole polymers was studied by electrochemical impedance spectroscopy and cyclic voltammetry. The results indicate the charge transfer behaviors occurred at nanocrystalline TiO 2 /electrolyte and Pt/electrolyte interface play an important role in influencing the photovoltaic performance of quasi-solid-state dye-sensitized solar cells

  18. Nanowire Photovoltaic Devices

    Science.gov (United States)

    Forbes, David

    2015-01-01

    Firefly Technologies, in collaboration with the Rochester Institute of Technology and the University of Wisconsin-Madison, developed synthesis methods for highly strained nanowires. Two synthesis routes resulted in successful nanowire epitaxy: direct nucleation and growth on the substrate and a novel selective-epitaxy route based on nanolithography using diblock copolymers. The indium-arsenide (InAs) nanowires are implemented in situ within the epitaxy environment-a significant innovation relative to conventional semiconductor nanowire generation using ex situ gold nanoparticles. The introduction of these nanoscale features may enable an intermediate band solar cell while simultaneously increasing the effective absorption volume that can otherwise limit short-circuit current generated by thin quantized layers. The use of nanowires for photovoltaics decouples the absorption process from the current extraction process by virtue of the high aspect ratio. While no functional solar cells resulted from this effort, considerable fundamental understanding of the nanowire epitaxy kinetics and nanopatterning process was developed. This approach could, in principle, be an enabling technology for heterointegration of dissimilar materials. The technology also is applicable to virtual substrates. Incorporating nanowires onto a recrystallized germanium/metal foil substrate would potentially solve the problem of grain boundary shunting of generated carriers by restricting the cross-sectional area of the nanowire (tens of nanometers in diameter) to sizes smaller than the recrystallized grains (0.5 to 1 micron(exp 2).

  19. Solar energy developments: photovoltaics

    International Nuclear Information System (INIS)

    Sivoththaman, S.

    2006-01-01

    The annual photovoltaic (PV) energy production crossed the 1 Gigawatt mark a couple of years ago, and continues to grow at rates exceeding 40%. The cost of PV has been continuously dropping due to increased production and also thanks to the technological advances made over the past two decades at the material, device, and system levels. Although PV is still considered expensive, cost-competitiveness is expected to be achieved in the next 5-10 years. With the current PV market 90% dominated by crystalline silicon (Si) material, advances are being made in tackling the Si shortage issue, and new approaches in feedstock refinement are getting shape. On the other hand, progress is being made on thin film-based advanced devices and on novel organic semiconductors. Novel concepts based on quantum physics and nanotechnology do have the ability to improve device performance beyond traditional theoretical limits. The domination of Si is expected to shift when these next generation technologies mature into industry-level scalability. On the system level, advanced back-end electronics provides more efficient power conditioning for modern PV modules. Systems level combinations such as solar thermal/PV hybrids and PV/hydrogen systems are also promising. An overview of recent technology developments will be presented with highlights in the Canadian scenario. (author)

  20. Schottky contact analysis of photovoltaic chalcopyrite thin film absorbers

    International Nuclear Information System (INIS)

    Schlenker, E.; Mertens, V.; Parisi, J.; Reineke-Koch, R.; Koentges, M.

    2007-01-01

    Current-voltage and capacitance-voltage measurements serve to analyze thermally evaporated Al Schottky contacts on Cu(In, Ga)Se 2 based photovoltaic thin film devices, either taken as grown or etched in a bromine-methanol solution. The characteristics of the Schottky contacts on the as-grown films give evidence for some dielectric layer developing between the metal and the semiconductor. Etching the semiconductor surface prior to evaporation of the Al front contact yields a pure metal-semiconductor behavior, including effects that can be attributed to an additional diode at the Mo contact. Simulations confirm the experimental results

  1. Improved Composite Gel Electrolyte by Layered Vermiculite for Quasi-Solid-State Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Hongcai He

    2014-01-01

    Full Text Available A composite quasisolid electrolyte is prepared by adding a layered vermiculite (VMT into the iodide/triiodide electrolyte including 4-tert-butylpyridine, which obviously improves the photovoltaic properties of quasisolid dye-sensitized solar cells (DSSCs. When adding 6 wt% VMT, the maximum photovoltaic conversion efficiency of 3.89% is obtained, which reaches more than two times greater than that without VMT. This enhancement effect is primarily explained by studying the Nyquist spectra, dark currents, and photovoltaic conversion efficiency.

  2. 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)

  3. FY 1993 report on the results of the technology development for the commercialization of the photovoltaic power system. Development of the solar cell use compound semiconductor production system - development of flight use testing machine; 1993 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Taiyo denchiyo kagobutsu handotai seizo sochi kaihatsu (hikoyo shikenki no kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    For a new breakthrough of the technology of the photovoltaic power generation, the paper aims at developing a combined heating furnace, a focal heating furnace and a single heating furnace which are necessary to produce crystals of the substrate of compound semiconductors for high quality solar cell under the microgravity environment obtained in the space, and also the systems related to the functions indispensable to the operation of the above-mentioned furnaces. This report is Vol. 2/3, and described the mission operation in Chapter 7, repair of PFM battery in Chapter 8, mechanical system ground support equipment and maintenance/inspection in Chapter 9, and electrical system ground support equipment and maintenance/repair in Chapter 10. In Chapter 7, described were the arrangement of operation of electrical furnace, operation manual of electrical furnace, procedures for operation, database, training, rehearsal plan, etc. In Chapter 8, of the battery repair plan, the paper carried out the repair design/repair work of battery, and described the state where a test to accept the test specifications is possible. In Chapter 9, indicated were the documents for application and reference of the maintenance/inspection of MGSE. In Chapter 10, the paper reported on the repairs for adaptation for the maintenance and lunching work of EGSE. (NEDO)

  4. Theoretical optoelectronic analysis of intermediate-band photovoltaic material based on ZnY1−xOx (Y = S, Se, Te) semiconductors by first-principles calculations

    International Nuclear Information System (INIS)

    Wu Kong-Ping; Zhou Meng-Ran; Huang You-Rui; Gu Shu-Lin; Ye Jian-Dong; Zhu Shun-Ming; Zhang Rong; Zheng You-Dou; Tang Kun

    2013-01-01

    The structural, energetic, and electronic properties of lattice highly mismatched ZnY 1−x O x (Y = S, Se, Te) ternary alloys with dilute O concentrations are calculated from first principles within the density functional theory. We demonstrate the formation of an isolated intermediate electronic band structure through diluted O-substitute in zinc-blende ZnY (Y = S, Se, Te) at octahedral sites in a semiconductor by the calculations of density of states (DOS), leading to a significant absorption below the band gap of the parent semiconductor and an enhancement of the optical absorption in the whole energy range of the solar spectrum. It is found that the intermediate band states should be described as a result of the coupling between impurity O 2p states with the conduction band states. Moreover, the intermediate bands (IBs) in ZnTeO show high stabilization with the change of O concentration resulting from the largest electronegativity difference between O and Te compared with in the other ZnSO and ZnSeO. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  5. Interfacial trap states in junctions of molecular semiconductors

    International Nuclear Information System (INIS)

    Schlettwein, D.; Oekermann, T.; Jaeger, N.; Armstrong, N.R.; Woehrle, D.

    2002-01-01

    Interfacial states that were established in contacts of molecular semiconductors with aqueous electrolytes or in contacts with another organic semiconductor as a solid film were analyzed by photoelectrochemical experiments and by photoelectron spectroscopy. A crucial role of such states was indicated in the interfacial charge transfer and recombination kinetics of light-induced charge carriers and also in the energetic alignment in the solid contacts. Unsubstituted zinc-phthalocyanine (PcZn) served as model compound. The role of chemical interactions in the establishment of these interfacial states was investigated by use of different reaction partners, i.e., different redox couples in the electrolyte contacts and molecular semiconductors of different ionization potential in the solid contacts. Implications of these results for the use of organic semiconductor thin films in devices of molecular electronics and of dye molecules in dye-sensitized solar cells were also discussed

  6. Semiconductor annealing

    International Nuclear Information System (INIS)

    Young, J.M.; Scovell, P.D.

    1981-01-01

    A process for annealing crystal damage in ion implanted semiconductor devices is described in which the device is rapidly heated to a temperature between 450 and 600 0 C and allowed to cool. It has been found that such heating of the device to these relatively low temperatures results in rapid annealing. In one application the device may be heated on a graphite element mounted between electrodes in an inert atmosphere in a chamber. The process may be enhanced by the application of optical radiation from a Xenon lamp. (author)

  7. Semiconductor Quantum Dots for Applications to Advanced Concepts for Solar Photon Conversion to Electricity and Solar Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Nozik, Arthur J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Beard, Matthew C [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-06

    The challenge of photoconversion research is to produce photovoltaic electricity at costs much less than those based on fossil fuels. Novel photoactive semiconductors and molecules of various types and structures are discussed for this purpose.

  8. Solar energy: photovoltaics

    International Nuclear Information System (INIS)

    Goetzberger, A.; Voss, B.; Knobloch, J.

    1994-01-01

    This textbooks covers the following topics: foundations of photovoltaics, solar energy, P-N junctions, physics of solar cells, high-efficiency solar cells, technology of Si solar cells, other solar cells, photovoltaic applications. (orig.)

  9. Photovoltaic roof construction

    Energy Technology Data Exchange (ETDEWEB)

    Hawley, W.W.

    1980-02-26

    In a batten-seam roof construction employing at least one photovoltaic cell module, the electrical conduits employed with the at least one photovoltaic cell module are disposed primarily under the battens of the roof.

  10. Magnetic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Bihler, Christoph

    2009-04-15

    In this thesis we investigated in detail the properties of Ga{sub 1-x}Mn{sub x}As, Ga{sub 1-x}Mn{sub x}P, and Ga{sub 1-x}Mn{sub x}N dilute magnetic semiconductor thin films with a focus on the magnetic anisotropy and the changes of their properties upon hydrogenation. We applied two complementary spectroscopic techniques to address the position of H in magnetic semiconductors: (i) Electron paramagnetic resonance, which provides direct information on the symmetry of the crystal field of the Mn{sup 2+} atoms and (ii) x-ray absorption fine structure analysis which allows to probe the local crystallographic neighborhood of the absorbing Mn atom via analysing the fine structure at the Mn K absorption edge. Finally, we discussed the obstacles that have to be overcome to achieve Curie temperatures above the current maximum in Ga{sub 1-x}Mn{sub x}As of 185 K. Here, we outlined in detail the generic problem of the formation of precipitates at the example of Ge:MN. (orig.)

  11. Photovoltaic power generation system with photovoltaic cells as bypass diodes

    Science.gov (United States)

    Lentine, Anthony L.; Nielson, Gregory N.; Tauke-Pedretti, Anna; Cruz-Campa, Jose Luis; Okandan, Murat

    2017-11-28

    A photovoltaic power generation system that includes a solar panel is described herein. The solar panel includes a photovoltaic sub-module, which includes a group of microsystem enabled photovoltaic cells. The group includes a first string of photovoltaic cells, a second string of photovoltaic cells, and a differing photovoltaic cell. Photovoltaic cells in the first string are electrically connected in series, and photovoltaic cells in the second string are electrically connected in series. Further, the first string of photovoltaic cells, the second string of photovoltaic cells, and the differing photovoltaic cell are electrically connected in parallel. Moreover, the differing photovoltaic cell is used as a bypass diode for the first string of photovoltaic cells and the second string of photovoltaic cells.

  12. Thermionic photovoltaic energy converter

    Science.gov (United States)

    Chubb, D. L. (Inventor)

    1985-01-01

    A thermionic photovoltaic energy conversion device comprises a thermionic diode mounted within a hollow tubular photovoltaic converter. The thermionic diode maintains a cesium discharge for producing excited atoms that emit line radiation in the wavelength region of 850 nm to 890 nm. The photovoltaic converter is a silicon or gallium arsenide photovoltaic cell having bandgap energies in this same wavelength region for optimum cell efficiency.

  13. Novelionic Polymer Electrolytes for Dye Sensitized Solar Cell

    Institute of Scientific and Technical Information of China (English)

    Li Wang; Shibi Fang; Yuan Lin

    2005-01-01

    @@ 1Introduction In recent years, dye-sensitized solar cells(DSC) based on nanocrystalline porous TiO2 films have attracted much attention because of their relatively higher efficiency and low cost compared with conventional inorganic photovoltaic devices[1]. This type of solar cell has achieved an impressive photo-to-energy conversion efficiency of over 10% where the electrolyte is volatile organic liquid solvents containing I-/I-3- as redox couple. Because of high volatilities, solvent losses occur during long-term operations, resulting in lowered DSC performances.And leakage of liquid electrolyte also limits the durability of DSC.

  14. Semiconductor Laser Measurements Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Semiconductor Laser Measurements Laboratory is equipped to investigate and characterize the lasing properties of semiconductor diode lasers. Lasing features such...

  15. Photovoltaic device and method

    Science.gov (United States)

    Cleereman, Robert J; Lesniak, Michael J; Keenihan, James R; Langmaid, Joe A; Gaston, Ryan; Eurich, Gerald K; Boven, Michelle L

    2015-01-27

    The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

  16. Organic photovoltaic effects depending on CuPc layer thickness

    International Nuclear Information System (INIS)

    Hur, Sung Woo; Kim, Tae Wan; Chung, Dong Hoe; Oh, Hyun Seok; Kim, Chung Hyeok; Lee, Joon Ung; Park, Jong Wook

    2004-01-01

    Organic photovoltaic effects were studied in device structures of ITO/CuPc/Al and ITO/CuPc/C 60 /BCP/Al by varying the CuPc layer thickness. Since the exciton diffusion length is relatively short in organic semiconductors, a study on the thickness-dependent photovoltaic effects is important. The thickness of the CuPc layer was varied from 10 nm to 50 nm. We found that the optimum CuPc layer thickness was around 40 nm from the analysis of the current density-voltage characteristics in an ITO/CuPc/Al photovoltaic cell. The efficiency of the device shows that the multi-layered heterojunction structure is more appropriate for photovoltaic cells.

  17. Photovoltaic Array Space Power flight experiment plus diagnostics (PASP+) modules

    International Nuclear Information System (INIS)

    Cooley, W.T.; Adams, S.F.; Reinhardt, K.C.; Piszczor, M.F.

    1992-01-01

    The Photovoltaic Array Space Power Plus Diagnostics flight experiment (PASP+) subsumes twelve solar array modules which represent the state of the art in the space photovoltaic array industry. Each of the twelve modules individually feature specific photovoltaic technologies such as advanced semiconductor materials, multi-bandgap structures, lightweight array designs, advanced interconnect technologies, or concentrator array designs. This paper will describe each module in detail including the configuration, components, materials, anticipated on orbit performance, and some of the aspects of each array technology. The layout of each module and the photovoltaic cell or array cross section will be presented graphically. A discussion on the environmental constraints and materials selection will be included as well as a delineation of the differences between the modules and the baseline array configuration in its intended application

  18. Transparent ultraviolet photovoltaic cells.

    Science.gov (United States)

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

  19. Thin film heterojunction photovoltaic cells and methods of making the same

    Science.gov (United States)

    Basol, Bulent M.; Tseng, Eric S.; Rod, Robert L.

    1983-06-14

    A method of fabricating a thin film heterojunction photovoltaic cell which comprises depositing a film of a near intrinsic or n-type semiconductor compound formed of at least one of the metal elements of Class II B of the Periodic Table of Elements and at least tellurium and then heating said film at a temperature between about 250.degree. C. and 500.degree. C. for a time sufficient to convert said film to a suitably low resistivity p-type semiconductor compound. Such film may be deposited initially on the surface of an n-type semiconductor substrate. Alternatively, there may be deposited on the converted film a layer of n-type semiconductor compound different from the film semiconductor compound. The resulting photovoltaic cell exhibits a substantially increased power output over similar cells not subjected to the method of the present invention.

  20. Semiconductor laser shearing interferometer

    International Nuclear Information System (INIS)

    Ming Hai; Li Ming; Chen Nong; Xie Jiaping

    1988-03-01

    The application of semiconductor laser on grating shearing interferometry is studied experimentally in the present paper. The method measuring the coherence of semiconductor laser beam by ion etching double frequency grating is proposed. The experimental result of lens aberration with semiconductor laser shearing interferometer is given. Talbot shearing interferometry of semiconductor laser is also described. (author). 2 refs, 9 figs

  1. 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

  2. Ceramic solid electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Goodenough, John B. [Center for Materials Science and Engineering, University of Texas at Austin, Austin, TX (United States)

    1997-02-15

    Strategies for the design of ceramic solid electrolytes are reviewed. Problems associated with stoichiometric and doped compounds are compared. In the illustration of design principles, emphasis is given to oxide-ion electrolytes for use in solid-oxide fuel cells, oxygen pumps, and oxygen sensors

  3. Promoting Effect of Layered Titanium Phosphate on the Electrochemical and Photovoltaic Performance of Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Deng Changsheng

    2010-01-01

    Full Text Available Abstract We reported a composite electrolyte prepared by incorporating layered α-titanium phosphate (α-TiP into an iodide-based electrolyte using 1-ethyl-3-methylimidazolium tetrafluoroborate(EmimBF4 ionic liquid as solvent. The obtained composite electrolyte exhibited excellent electrochemical and photovoltaic properties compared to pure ionic liquid electrolyte. Both the diffusion coefficient of triiodide (I3 − in the electrolyte and the charge-transfer reaction at the electrode/electrolyte interface were improved markedly. The mechanism for the enhanced electrochemical properties of the composite electrolyte was discussed. The highest conversion efficiency of dye-sensitized solar cell (DSSC was obtained for the composite electrolyte containing 1wt% α-TiP, with an improvement of 58% in the conversion efficiency than the blank one, which offered a broad prospect for the fabrication of stable DSSCs with a high conversion efficiency.

  4. Fullerene derivatives as electron acceptors for organic photovoltaic cells.

    Science.gov (United States)

    Mi, Dongbo; Kim, Ji-Hoon; Kim, Hee Un; Xu, Fei; Hwang, Do-Hoon

    2014-02-01

    Energy is currently one of the most important problems humankind faces. Depletion of traditional energy sources such as coal and oil results in the need to develop new ways to create, transport, and store electricity. In this regard, the sun, which can be considered as a giant nuclear fusion reactor, represents the most powerful source of energy available in our solar system. For photovoltaic cells to gain widespread acceptance as a source of clean and renewable energy, the cost per watt of solar energy must be decreased. Organic photovoltaic cells, developed in the past two decades, have potential as alternatives to traditional inorganic semiconductor photovoltaic cells, which suffer from high environmental pollution and energy consumption during production. Organic photovoltaic cells are composed of a blended film of a conjugated-polymer donor and a soluble fullerene-derivative acceptor sandwiched between a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)-coated indium tin oxide positive electrode and a low-work-function metal negative electrode. Considerable research efforts aim at designing and synthesizing novel fullerene derivatives as electron acceptors with up-raised lowest unoccupied molecular orbital energy, better light-harvesting properties, higher electron mobility, and better miscibility with the polymer donor for improving the power conversion efficiency of the organic photovoltaic cells. In this paper, we systematically review novel fullerene acceptors synthesized through chemical modification for enhancing the photovoltaic performance by increasing open-circuit voltage, short-circuit current, and fill factor, which determine the performance of organic photovoltaic cells.

  5. Photovoltaic Materials

    Energy Technology Data Exchange (ETDEWEB)

    Duty, C.; Angelini, J.; Armstrong, B.; Bennett, C.; Evans, B.; Jellison, G. E.; Joshi, P.; List, F.; Paranthaman, P.; Parish, C.; Wereszczak, A.

    2012-10-15

    The goal of the current project was to help make the US solar industry a world leader in the manufacture of thin film photovoltaics. The overall approach was to leverage ORNL’s unique characterization and processing technologies to gain a better understanding of the fundamental challenges for solar cell processing and apply that knowledge to targeted projects with industry members. ORNL has the capabilities in place and the expertise required to understand how basic material properties including defects, impurities, and grain boundaries affect the solar cell performance. ORNL also has unique processing capabilities to optimize the manufacturing process for fabrication of high efficiency and low cost solar cells. ORNL recently established the Center for Advanced Thin-film Systems (CATS), which contains a suite of optical and electrical characterization equipment specifically focused on solar cell research. Under this project, ORNL made these facilities available to industrial partners who were interested in pursuing collaborative research toward the improvement of their product or manufacturing process. Four specific projects were pursued with industrial partners: Global Solar Energy is a solar industry leader in full scale production manufacturing highly-efficient Copper Indium Gallium diSelenide (CIGS) thin film solar material, cells and products. ORNL worked with GSE to develop a scalable, non-vacuum, solution technique to deposit amorphous or nanocrystalline conducting barrier layers on untextured stainless steel substrates for fabricating high efficiency flexible CIGS PV. Ferro Corporation’s Electronic, Color and Glass Materials (“ECGM”) business unit is currently the world’s largest supplier of metallic contact materials in the crystalline solar cell marketplace. Ferro’s ECGM business unit has been the world's leading supplier of thick film metal pastes to the crystalline silicon PV industry for more than 30 years, and has had operational

  6. Human Water and Electrolyte Balance

    National Research Council Canada - National Science Library

    Montain, S. J; Cheuvront, S. N; Carter, R; Sawka, M. N

    2006-01-01

    .... Sweat losses, if not replaced, reduce body water volume and electrolyte content. Excessive body water or electrolyte losses can disrupt physiological homeostasis and threaten both health and performance...

  7. A photovoltaic module

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a photovoltaic module comprising a carrier substrate, said carrier substrate carrying a purely printed structure comprising printed positive and negative module terminals, a plurality of printed photovoltaic cell units each comprising one or more printed...... photovoltaic cells, wherein the plurality of printed photovoltaic cell units are electrically connected in series between the positive and the negative module terminals such that any two neighbouring photovoltaic cell units are electrically connected by a printed interconnecting electrical conductor....... The carrier substrate comprises a foil and the total thickness of the photovoltaic module is below 500 [mu]m. Moreover, the nominal voltage level between the positive and the negative terminals is at least 5 kV DC....

  8. Photovoltaic systems in agriculture

    International Nuclear Information System (INIS)

    Corba, Z.; Katic, V.; Milicevic, D.

    2009-01-01

    This paper presents the possibility of using one of the renewable energy resources in agriculture. Specifically, the paper shows the possibility of converting solar energy into electricity through photovoltaic panels. The paper includes the analysis of the energy potential of solar radiation in the AP Vojvodina (Serbia). The results of the analysis can be used for the design of photovoltaic energy systems. The amount of solar energy on the territory of the province is compared with the same data from some European countries, in order to obtain a clear picture of the possibilities of utilization of this type of renewable sources. Three examples of possible application of photovoltaic systems are presented. The first relates to the consumer who is away from the electric distribution network - photovoltaic system in island mode. The remaining two examples relate to the application of photovoltaic power sources in manufacturing plants, flowers or vegetables. Applying photovoltaic source of electrical energy to power pumps for irrigation is highlighted

  9. Electrolyte for batteries with regenerative solid electrolyte interface

    Science.gov (United States)

    Xiao, Jie; Lu, Dongping; Shao, Yuyan; Bennett, Wendy D.; Graff, Gordon L.; Liu, Jun; Zhang, Ji-Guang

    2017-08-01

    An energy storage device comprising: an anode; and a solute-containing electrolyte composition wherein the solute concentration in the electrolyte composition is sufficiently high to form a regenerative solid electrolyte interface layer on a surface of the anode only during charging of the energy storage device, wherein the regenerative layer comprises at least one solute or solvated solute from the electrolyte composition.

  10. Silicon nanowires for photovoltaic solar energy conversion.

    Science.gov (United States)

    Peng, Kui-Qing; Lee, Shuit-Tong

    2011-01-11

    Semiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new-generation photovoltaic (PV) technology. In particular, silicon nanowires (SiNWs) are under active investigation for PV applications because they offer novel approaches for solar-to-electric energy conversion leading to high-efficiency devices via simple manufacturing. This article reviews the recent developments in the utilization of SiNWs for PV applications, the relationship between SiNW-based PV device structure and performance, and the challenges to obtaining high-performance cost-effective solar cells.

  11. Photovoltaic energy technologies: Health and environmental effects document

    Science.gov (United States)

    Moskowitz, P. D.; Hamilton, L. D.; Morris, S. C.; Rowe, M. D.

    1980-09-01

    The potential health and environmental consequences of producing electricity by photovoltaic energy systems was analyzed. Potential health and environmental risks are identified in representative fuel and material supply cycles including extraction, processing, refining, fabrication, installation, operation, and isposal for four photovoltaic energy systems (silicon N/P single crystal, silicon metal/insulator/semiconductor (MIS) cell, cadmium sulfide/copper sulfide backwall cell, and gallium arsenide heterojunction cell) delivering equal amounts of useful energy. Each step of the fuel and material supply cycles, materials demands, byproducts, public health, occupational health, and environmental hazards is identified.

  12. Photovoltaic Solar Energy

    International Nuclear Information System (INIS)

    Gonzalez N, J.C.; Leal C, H.

    1998-01-01

    A short historical review of the technological advances; the current state and the perspectives of the materials for photovoltaic applications is made. Thereinafter, the general aspects of the physical principles and fundamental parameters that govern the operation of the solar cells are described. To way of the example, a methodology for the design and facilities size of a photovoltaic system is applied. Finally, the perspectives of photovoltaic solar energy in relationship to the market and political of development are mentioned

  13. Modeling Photovoltaic Power

    OpenAIRE

    Mavromatakis, F.; Franghiadakis, Y.; Vignola, F.

    2016-01-01

    A robust and reliable model describing the power produced by a photovoltaic system is needed in order to be able to detect module failures, inverter malfunction, shadowing effects and other factors that may result to energy losses. In addition, a reliable model enables an investor to perform accurate estimates of the system energy production, payback times etc. The model utilizes the global irradiance reaching the plane of the photovoltaic modules since in almost all Photovoltaic (PV) facilit...

  14. 2012 Gordon Research Conference on Defects in Semiconductors - Formal Schedule and Speaker/Poster Program

    Energy Technology Data Exchange (ETDEWEB)

    Glaser, Evan [Naval Research Lab. (NRL), Washington, DC (United States)

    2012-08-17

    The meeting shall strive to develop and further the fundamental understanding of defects and their roles in the structural, electronic, optical, and magnetic properties of bulk, thin film, and nanoscale semiconductors and device structures. Point and extended defects will be addressed in a broad range of electronic materials of particular current interest, including wide bandgap semiconductors, metal-oxides, carbon-based semiconductors (e.g., diamond, graphene, etc.), organic semiconductors, photovoltaic/solar cell materials, and others of similar interest. This interest includes novel defect detection/imaging techniques and advanced defect computational methods.

  15. Thin Film Photovoltaic/Thermal Solar Panels

    Institute of Scientific and Technical Information of China (English)

    David JOHNSTON

    2008-01-01

    A solar panel is described.in which thin films of semiconductor are deposited onto a metal substrate.The semiconductor-metal combination forms a thin film photovoltaic cell,and also acts as a reflector,absorber tandem, which acts as a solar selective surface,thus enhancing the solar thermal performance of the collector plate.The use of thin films reduces the distance heat is required to flow from the absorbing surface to the metal plate and heat exchange conduits.Computer modelling demonstrated that,by suitable choice of materials,photovohaic efficiency call be maintained,with thermal performance slishtly reduced,compared to that for thermal-only panels.By grading the absorber layer-to reduce the band gap in the lower region-the thermal performance can be improved,approaching that for a thermal-only solar panel.

  16. Photovoltaic energy barometer

    International Nuclear Information System (INIS)

    Anon.

    2007-01-01

    The european photovoltaic market once again reached the heights in 2006, thanks to the dynamism of the German market. White paper objectives have thus been fulfilled four years ahead of schedule. The european photovoltaic sector remains however very heterogeneous with both an ultra-dominant German market (estimated at 1150 MWp in 2006) and other countries of the European Union that vary from a few kWP to a few dozen MWp. This analysis provides statistical data on the market, the capacity installed during 2005 and 2006, the photovoltaic parks and the evolution of the photovoltaic cell production. (A.L.B.)

  17. Fundamentals of semiconductor devices

    CERN Document Server

    Lindmayer, Joseph

    1965-01-01

    Semiconductor properties ; semiconductor junctions or diodes ; transistor fundamentals ; inhomogeneous impurity distributions, drift or graded-base transistors ; high-frequency properties of transistors ; band structure of semiconductors ; high current densities and mechanisms of carrier transport ; transistor transient response and recombination processes ; surfaces, field-effect transistors, and composite junctions ; additional semiconductor characteristics ; additional semiconductor devices and microcircuits ; more metal, insulator, and semiconductor combinations for devices ; four-pole parameters and configuration rotation ; four-poles of combined networks and devices ; equivalent circuits ; the error function and its properties ; Fermi-Dirac statistics ; useful physical constants.

  18. Constructions of aluminium electrolytic cells

    International Nuclear Information System (INIS)

    Galushkin, N.V.

    1995-01-01

    This chapter of monograph is devoted to constructions of aluminium electrolytic cells. Therefore, the general characteristic and classification of aluminium electrolytic cells was considered. The anode and cathode structure was studied. The lining of cathode casing, the process of collection of anode gases, electrolytic cell cover, and electrical insulation was studied as well. The installation and dismantling of aluminium electrolytic cells was described.

  19. Retraction of “Accurate Prediction of Essential Fundamental Properties for Semiconductors Used in Solar-Energy Conversion Devices from Range-Separated Hybrid Density Functional Theory”

    KAUST Repository

    Harb, Moussab

    2016-01-01

    The author retracts this article due to similarities with a previously published article by Le Bahers, T.; Rerat, M.; Sautet, ́ P. Semiconductors Used in Photovoltaic and Photocatalytic Devices: Assessing Fundamental Properties from DFT. J. Phys

  20. Nanoscale Organic Hybrid Electrolytes

    KAUST Repository

    Nugent, Jennifer L.

    2010-08-20

    Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Nuclear electrolytic hydrogen

    International Nuclear Information System (INIS)

    Barnstaple, A.G.; Petrella, A.J.

    1982-05-01

    An extensive study of hydrogen supply has recently been carried out by Ontario Hydro which indicates that electrolytic hydrogen produced from nuclear electricity could offer the lowest cost option for any future large scale hydrogen supply in the Province of Ontario, Canada. This paper provides a synopsis of the Ontario Hydro study, a brief overview of the economic factors supporting the study conclusion and discussion of a number of issues concerning the supply of electrolytic hydrogen by electric power utilities

  2. Nanoscale Organic Hybrid Electrolytes

    KAUST Repository

    Nugent, Jennifer L.; Moganty, Surya S.; Archer, Lynden A.

    2010-01-01

    Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Liquid Crystalline Semiconductors Materials, properties and applications

    CERN Document Server

    Kelly, Stephen; O'Neill, Mary

    2013-01-01

    This is an exciting stage in the development of organic electronics. It is no longer an area of purely academic interest as increasingly real applications are being developed, some of which are beginning to come on-stream. Areas that have already been commercially developed or which are under intensive development include organic light emitting diodes (for flat panel displays and solid state lighting), organic photovoltaic cells, organic thin film transistors (for smart tags and flat panel displays) and sensors. Within the family of organic electronic materials, liquid crystals are relative newcomers. The first electronically conducting liquid crystals were reported in 1988 but already a substantial literature has developed. The advantage of liquid crystalline semiconductors is that they have the easy processability of amorphous and polymeric semiconductors but they usually have higher charge carrier mobilities. Their mobilities do not reach the levels seen in crystalline organics but they circumvent all of t...

  4. Determining the coating speed limitations for organic photovoltaic inks

    DEFF Research Database (Denmark)

    Jakubka, Florian; Heyder, Madeleine; Machui, Florian

    2013-01-01

    To determine the output capability of present organic photovoltaic (OPV) materials, it is important to know the theoretical maximum coating speeds of the used semiconductor formulations. Here, we present a comprehensive investigation of the coating stability window of several prototype organic...... semiconductor inks relevant for organic solar cells. The coating stability window was first determined experimentally by a sheet to sheet coater at velocities of up to 10 m/min. A numerical simulation model based on the Coating Window Suite 2010 software was established to give insight into the coating...

  5. Photovoltaic research and development

    CSIR Research Space (South Africa)

    Cummings, F

    2009-09-01

    Full Text Available Photovoltaic (PV) is the direct conversion of sunlight into electrical energy through a solar cell. This presentation consists of an introduction to photovoltaics, the South African PV research roadmap, a look at the CSIR PV research and development...

  6. Characterization of Photovoltaic Generators

    Science.gov (United States)

    Boitier, V.; Cressault, Y.

    2011-01-01

    This paper discusses photovoltaic panel systems and reviews their electrical properties and use in several industrial fields. We explain how different photovoltaic panels may be characterized by undergraduate students at university using simple methods to retrieve their electrical properties (power, current and voltage) and compare these values…

  7. Photovoltaic Bias Generator

    Science.gov (United States)

    2018-02-01

    Department of the Army position unless so designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an... Interior view of the photovoltaic bias generator showing wrapped-wire side of circuit board...3 Fig. 4 Interior view of the photovoltaic bias generator showing component side of circuit board

  8. Solar Photovoltaic Energy.

    Science.gov (United States)

    Ehrenreich, Henry; Martin, John H.

    1979-01-01

    The goals of solar photovoltaic technology in contributing to America's future energy needs are presented in this study conducted by the American Physical Society. Although the time needed for photovoltaics to become popular is several decades away, according to the author, short-range applications are given. (Author/SA)

  9. Urban photovoltaic electricity policies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-15

    This report for the International Energy Agency (IEA) made by Task 10 of the Photovoltaic Power Systems (PVPS) programme takes a look at urban photovoltaic electricity policies. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy as a significant and sustainable renewable energy option. The objective of Task 10 is stated as being to enhance the opportunities for wide-scale, solution-oriented application of photovoltaics in the urban environment. The goal of the study presented was to evaluate a standardised basis for urban policies regarding photovoltaic integration in a set of cities in the countries participating in the IEA's Task 10, Urban Scale PV. The investigation was focused on three topics: the present state of the policies, the prospects for future policies fostering photovoltaic deployment and the prospects for future policies to cope with large-scale photovoltaic integration. The first section analyses the state of the policies; this analysis is then confirmed in section 2, which deals with present obstacles to PV deployment and solutions to overcome them. The third section investigates future prospects for PV deployment with the question of mastering large scale integration. The report concludes that cities could formulate urban solutions by developing integrated, specific provisions for PV deployment in their urban infrastructure planning.

  10. Photovoltaics in Poland

    International Nuclear Information System (INIS)

    Pietruszko, Stanislaw M.

    2003-01-01

    The legislative framework and financing possibilities for photovoltaics (PV) in Poland are presented. Barriers that exist or can be encountered in implementing PV technology in Poland are identified. This paper also discusses future prospects and possibilities for developing photovoltaics in Poland. Finally, the paper suggests ways to promote, disseminate, and deploy PV technology in Poland. (Author)

  11. Solid spectroscopy: semiconductors

    International Nuclear Information System (INIS)

    Silva, C.E.T.G. da

    1983-01-01

    Photoemission as technique of study of the semiconductor electronic structure is shortly discussed. Homogeneous and heterogeneous semiconductors, where volume and surface electronic structure, core levels and O and H chemisorption in GaAs, Schottky barrier are treated, respectively. Amorphous semiconductors are also discussed. (L.C.) [pt

  12. Applications of photovoltaics

    International Nuclear Information System (INIS)

    Pearsall, N.

    1999-01-01

    The author points out that although photovoltaics can be used for generating electricity for the same applications as many other means of generation, they really come into their own where disadvantages associated with an intermittent unpredictable supply are not severe. The paper discusses the advantages and disadvantages to be taken into account when considering a photovoltaic power system. Five main applications, based on the system features, are listed and explained. They are: consumer, professional, rural electrification, building-integrated, centralised grid connected and space power. A brief history of the applications of photovoltaics is presented with statistical data on the growth of installed capacity since 1992. The developing market for photovoltaics is discussed together with how environmental issues have become a driver for development of building-integrated photovoltaics

  13. Enlarging photovoltaic effect: combination of classic photoelectric and ferroelectric photovoltaic effects.

    Science.gov (United States)

    Zhang, Jingjiao; Su, Xiaodong; Shen, Mingrong; Dai, Zhihua; Zhang, Lingjun; He, Xiyun; Cheng, Wenxiu; Cao, Mengyu; Zou, Guifu

    2013-01-01

    Converting light energy to electrical energy in photovoltaic devices relies on the photogenerated electrons and holes separated by the built-in potential in semiconductors. Photo-excited electrons in metal electrodes are usually not considered in this process. Here, we report an enhanced photovoltaic effect in the ferroelectric lanthanum-modified lead zirconate titanate (PLZT) by using low work function metals as the electrodes. We believe that electrons in the metal with low work function could be photo-emitted into PLZT and form the dominant photocurrent in our devices. Under AM1.5 (100 mW/cm²) illumination, the short-circuit current and open-circuit voltage of Mg/PLZT/ITO are about 150 and 2 times of those of Pt/PLZT/ITO, respectively. The photovoltaic response of PLZT capacitor was expanded from ultraviolet to visible spectra, and it may have important impact on design and fabrication of high performance photovoltaic devices based on ferroelectric materials.

  14. Elucidation and control of electronic properties related to organic semiconductors

    International Nuclear Information System (INIS)

    Yamane, Hiroyuki; Ueno, Nobuo; Seki, Kazuhiko

    2009-01-01

    The electronic structure of organic solids and interfaces plays a crucial role in the performance of optoelectronic devices using organic semiconductors such as light-emitting diodes, field-effect transistors, and photovoltaic cells. The functionality of these organic devices is seriously dominated by the geometric structure, which varies depending on the molecular structure and the sample preparation condition. Due to the rapid progress in sample preparation methods and surface science techniques, we can now discuss in detail the correlation of the electronic structure with the geometric structure of organic solids, films, and interfaces. This paper reviews the recent progress of studies in the geometric and electronic structures related to organic semiconductors. (author)

  15. Monte-Carlo simulation of crystallographical pore growth in III-V-semiconductors

    International Nuclear Information System (INIS)

    Leisner, Malte; Carstensen, Juergen; Foell, Helmut

    2011-01-01

    The growth of crystallographical pores in III-V-semiconductors can be understood in the framework of a simple model, which is based on the assumption that the branching of pores is proportional to the current density at the pore tips. The stochastic nature of this model allows its implementation into a three-dimensional Monte-Carlo-simulation of pore growth. The simulation is able to reproduce the experimentally observed crysto pore structures in III-V-semiconductors in full quantitative detail. The different branching probabilities for different semiconductors, as well as doping levels, can be deduced from the specific passivation behavior of the semiconductor-electrolyte-interface at the pore tips.

  16. Acetylene-Based Materials in Organic Photovoltaics

    Directory of Open Access Journals (Sweden)

    Fabio Silvestri

    2010-04-01

    Full Text Available Fossil fuel alternatives, such as solar energy, are moving to the forefront in a variety of research fields. Organic photovoltaic systems hold the promise of a lightweight, flexible, cost-effective solar energy conversion platform, which could benefit from simple solution-processing of the active layer. The discovery of semiconductive polyacetylene by Heeger et al. in the late 1970s was a milestone towards the use of organic materials in electronics; the development of efficient protocols for the palladium catalyzed alkynylation reactions and the new conception of steric and conformational advantages of acetylenes have been recently focused the attention on conjugated triple-bond containing systems as a promising class of semiconductors for OPVs applications. We review here the most important and representative (polyarylacetylenes that have been used in the field. A general introduction to (polyarylacetylenes, and the most common synthetic approaches directed toward making these materials will be firstly given. After a brief discussion on working principles and critical parameters of OPVs, we will focus on molecular arylacetylenes, (copolymers containing triple bonds, and metallopolyyne polymers as p-type semiconductor materials. The last section will deal with hybrids in which oligomeric/polymeric structures incorporating acetylenic linkages such as phenylene ethynylenes have been attached onto C60, and their use as the active materials in photovoltaic devices.

  17. Organic / IV, III-V Semiconductor Hybrid Solar Cells

    Directory of Open Access Journals (Sweden)

    Pang-Leen Ong

    2010-03-01

    Full Text Available We present a review of the emerging class of hybrid solar cells based on organic-semiconductor (Group IV, III-V, nanocomposites, which states separately from dye synthesized, polymer-metal oxides and organic-inorganic (Group II-VI nanocomposite photovoltaics. The structure of such hybrid cell comprises of an organic active material (p-type deposited by coating, printing or spraying technique on the surface of bulk or nanostructured semiconductor (n-type forming a heterojunction between the two materials. Organic components include various photosensitive monomers (e.g., phtalocyanines or porphyrines, conjugated polymers, and carbon nanotubes. Mechanisms of the charge separation at the interface and their transport are discussed. Also, perspectives on the future development of such hybrid cells and comparative analysis with other classes of photovoltaics of third generation are presented.

  18. Physics of Quantum Structures in Photovoltaic Devices

    Science.gov (United States)

    Raffaelle, Ryne P.; Andersen, John D.

    2005-01-01

    There has been considerable activity recently regarding the possibilities of using various nanostructures and nanomaterials to improve photovoltaic conversion of solar energy. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of three-dimensional arrays of zero-dimensional conductors (i.e., quantum dots) in an ordinary p-i-n solar cell structure. Quantum dots and other nanostructured materials may also prove to have some benefits in terms of temperature coefficients and radiation degradation associated with space solar cells. Two-dimensional semiconductor superlattices have already demonstrated some advantages in this regard. It has also recently been demonstrated that semiconducting quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. Improvement in thin film cells utilizing conjugated polymers has also be achieved through the use of one-dimensional quantum structures such as carbon nanotubes. It is believed that carbon nanotubes may contribute to both the disassociation as well as the carrier transport in the conjugated polymers used in certain thin film photovoltaic cells. In this paper we will review the underlying physics governing some of the new photovoltaic nanostructures being pursued, as well as the the current methods being employed to produce III-V, II-VI, and even chalcopyrite-based nanomaterials and nanostructures for solar cells.

  19. Catalyzed reactions at illuminated semiconductor interfaces

    International Nuclear Information System (INIS)

    Wrighton, M.S.

    1984-01-01

    Many desirable minority carrier chemical redox processes are too slow to compete with e - -h + recombination at illuminated semiconductor/liquid electrolyte junction interfaces. Reductions of H 2 O to H 2 or CO 2 to compounds having C--H bonds are too slow to compete with e - -h + recombination at illuminated p-type semiconductors, for example. Approaches to improve the rate of the desired processes involving surface modification techniques are described. Photoanodes are plagued by the additional problem of oxidative decomposition under illumination with > or =E/sub g/ illumination. The photo-oxidation of Cl - , Br - , and H 2 O is considered to illustrate the concepts involved. Proof of concept experiments establish that catalysis can be effective in dramatically improving direct solar fuel production; efficiencies of >10% have been demonstrated

  20. Solid electrolyte fuel cells

    Science.gov (United States)

    Isaacs, H. S.

    Progress in the development of functioning solid electrolyte fuel cells is summarized. The solid electrolyte cells perform at 1000 C, a temperature elevated enough to indicate high efficiencies are available, especially if the cell is combined with a steam generator/turbine system. The system is noted to be sulfur tolerant, so coal containing significant amounts of sulfur is expected to yield satisfactory performances with low parasitic losses for gasification and purification. Solid oxide systems are electrically reversible, and are usable in both fuel cell and electrolysis modes. Employing zirconium and yttrium in the electrolyte provides component stability with time, a feature not present with other fuel cells. The chemical reactions producing the cell current are reviewed, along with materials choices for the cathodes, anodes, and interconnections.

  1. Gel electrolytes and electrodes

    Science.gov (United States)

    Fleischmann, Sven; Bunte, Christine; Mikhaylik, Yuriy V.; Viner, Veronika G.

    2017-09-05

    Gel electrolytes, especially gel electrolytes for electrochemical cells, are generally described. In some embodiments, the gel electrolyte layers comprise components a) to c). Component a) may be at least one layer of at least one polymer comprising polymerized units of: a1) at least one monomer containing an ethylenically unsaturated unit and an amido group and a2) at least one crosslinker. Component b) may be at least one conducting salt and component c) may be at least one solvent. Electrodes may comprise the components a), d) and e), wherein component a) may be at least one layer of at least one polymer as described herein. Component d) may be at least one electroactive layer and component e) may be at least one ceramic layer. Furthermore, electrochemical cells comprising component a) which may be at least one layer of at least one polymer as described herein, are also provided.

  2. Method for making graded I-III-VI.sub.2 semiconductors and solar cell obtained thereby

    Science.gov (United States)

    Devaney, Walter E.

    1987-08-04

    Improved cell photovoltaic conversion efficiencies are obtained by the simultaneous elemental reactive evaporation process of Mickelsen and Chen for making semiconductors by closer control of the evaporation rates and substrate temperature during formation of the near contact, bulk, and near junction regions of a graded I-III-VI.sub.2, thin film, semiconductor, such as CuInSe.sub.2 /(Zn,Cd)S or another I-III-VI.sub.2 /II-VI heterojunction.

  3. Plastic encapsulated, dye sensitised photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Potter, R.J.; Otley, L.C.; Durrant, J.R.; Haque, S.; Xu, C. [Imperial College of Science, Technology and Medicine, London (United Kingdom); Holmes, A.B.; Park, T.; Schulte, N. [Cambridge Univ. (United Kingdom)

    2004-07-01

    The report presents the results of a collaborative project that aimed to demonstrate the technical feasibility of a plastic-encapsulated, solid state, dye-sensitised solar cell (DSSC) with an energy conversion efficiency (ECE) of at least 3%. DSSCs offer a possible 'step change' in photovoltaic technology resulting in lower costs compared with existing technologies. The project involved a series of eight main tasks: the development of first and second generation HTM electrolytes; the development of polymer-supported electrolytes; the development of low temperature electrode coating procedures; dye development; cell assembly and testing; component integration; and overall process development. A wide range of innovative HTMs have been synthesised, including materials incorporating both hole-transporting and ion-chelating functional groups. The ruthenium-based dye, N3, remained the preferred sensitising component. The project has produced a system that can routinely achieve over 5% ECE at 0.1 Sun illumination on 1 cm{sup 2} cells using polymer-supported electrolytes.

  4. Semiconductor-based, large-area, flexible, electronic devices

    Science.gov (United States)

    Goyal, Amit [Knoxville, TN

    2011-03-15

    Novel articles and methods to fabricate the same resulting in flexible, large-area, triaxially textured, single-crystal or single-crystal-like, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  5. Thin Film Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, K.

    1998-11-19

    The motivation to develop thin film technologies dates back to the inception of photovoltaics. It is an idea based on achieving truly low-cost photovoltaics appropriate for mass production and energy significant markets. The key to the idea is the use of pennies worth of active materials. Since sunlight carries relatively little energy in comparison with combustion-based energy sources, photovoltaic (PV) modules must be cheap to produce energy that can be competitive. Thin films are presumed to be the answer to that low-cost requirement. But how cheap do they have to be? The following is an oversimplified analysis that allows some insight into this question.

  6. Survey of photovoltaic systems

    Energy Technology Data Exchange (ETDEWEB)

    1979-08-01

    In developing this survey of photovoltaic systems, the University of Alabama in Huntsville assembled a task team to perform an extensive telephone survey of all known photovoltaic manufacturers. Three US companies accounted for 77% of the total domestic sales in 1978. They are Solarex Corporation, Solar Power Croporation, and ARCO Solar, Inc. This survey of solar photovoltaic (P/V) manufacturers and suppliers consists of three parts: a catalog of suppliers arranged alphabetically, data sheets on specific products, and typical operating, installation, or maintenance instructions and procedures. This report does not recommend or endorse any company product or information presented within as the results of this survey.

  7. Clean electricity from photovoltaics

    CERN Document Server

    Green, Martin A

    2015-01-01

    The second edition of Clean Electricity from Photovoltaics , first published in 2001, provides an updated account of the underlying science, technology and market prospects for photovoltaics. All areas have advanced considerably in the decade since the first edition was published, which include: multi-crystalline silicon cell efficiencies having made impressive advances, thin-film CdTe cells having established a decisive market presence, and organic photovoltaics holding out the prospect of economical large-scale power production. Contents: The Past and Present (M D Archer); Limits to Photovol

  8. Electrolytic decontamination of stainless steel using a basic electrolyte

    International Nuclear Information System (INIS)

    Childs, E.L.; Long, J.L.

    1981-01-01

    An electrolytic plutonium decontamination process or stainless steel was developed for use as the final step in a proposed radioactive waste handling and decontamination facility to be construced at the Rockwell International Rocky Flats plutonium handling facility. This paper discusses test plan, which was executed to compare the basic electrolyte with phosphoric acid and nitric acid electrolytes. 1 ref

  9. Compound Semiconductor Radiation Detector

    International Nuclear Information System (INIS)

    Kim, Y. K.; Park, S. H.; Lee, W. G.; Ha, J. H.

    2005-01-01

    In 1945, Van Heerden measured α, β and γ radiations with the cooled AgCl crystal. It was the first radiation measurement using the compound semiconductor detector. Since then the compound semiconductor has been extensively studied as radiation detector. Generally the radiation detector can be divided into the gas detector, the scintillator and the semiconductor detector. The semiconductor detector has good points comparing to other radiation detectors. Since the density of the semiconductor detector is higher than that of the gas detector, the semiconductor detector can be made with the compact size to measure the high energy radiation. In the scintillator, the radiation is measured with the two-step process. That is, the radiation is converted into the photons, which are changed into electrons by a photo-detector, inside the scintillator. However in the semiconductor radiation detector, the radiation is measured only with the one-step process. The electron-hole pairs are generated from the radiation interaction inside the semiconductor detector, and these electrons and charged ions are directly collected to get the signal. The energy resolution of the semiconductor detector is generally better than that of the scintillator. At present, the commonly used semiconductors as the radiation detector are Si and Ge. However, these semiconductor detectors have weak points. That is, one needs thick material to measure the high energy radiation because of the relatively low atomic number of the composite material. In Ge case, the dark current of the detector is large at room temperature because of the small band-gap energy. Recently the compound semiconductor detectors have been extensively studied to overcome these problems. In this paper, we will briefly summarize the recent research topics about the compound semiconductor detector. We will introduce the research activities of our group, too

  10. Semiconductor apparatus and method of fabrication for a semiconductor apparatus

    NARCIS (Netherlands)

    2010-01-01

    The invention relates to a semiconductor apparatus (1) and a method of fabrication for a semiconductor apparatus (1), wherein the semiconductor apparatus (1) comprises a semiconductor layer (2) and a passivation layer (3), arranged on a surface of the semiconductor layer (2), for passivating the

  11. Photovoltaic Pixels for Neural Stimulation: Circuit Models and Performance.

    Science.gov (United States)

    Boinagrov, David; Lei, Xin; Goetz, Georges; Kamins, Theodore I; Mathieson, Keith; Galambos, Ludwig; Harris, James S; Palanker, Daniel

    2016-02-01

    Photovoltaic conversion of pulsed light into pulsed electric current enables optically-activated neural stimulation with miniature wireless implants. In photovoltaic retinal prostheses, patterns of near-infrared light projected from video goggles onto subretinal arrays of photovoltaic pixels are converted into patterns of current to stimulate the inner retinal neurons. We describe a model of these devices and evaluate the performance of photovoltaic circuits, including the electrode-electrolyte interface. Characteristics of the electrodes measured in saline with various voltages, pulse durations, and polarities were modeled as voltage-dependent capacitances and Faradaic resistances. The resulting mathematical model of the circuit yielded dynamics of the electric current generated by the photovoltaic pixels illuminated by pulsed light. Voltages measured in saline with a pipette electrode above the pixel closely matched results of the model. Using the circuit model, our pixel design was optimized for maximum charge injection under various lighting conditions and for different stimulation thresholds. To speed discharge of the electrodes between the pulses of light, a shunt resistor was introduced and optimized for high frequency stimulation.

  12. Photovoltaic module and interlocked stack of photovoltaic modules

    Science.gov (United States)

    Wares, Brian S.

    2014-09-02

    One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame. A plurality of individual male alignment features and a plurality of individual female alignment features are included on each frame. Adjacent photovoltaic modules are interlocked by multiple individual male alignment features on a first module of the adjacent photovoltaic modules fitting into and being surrounded by corresponding individual female alignment features on a second module of the adjacent photovoltaic modules. Other embodiments, features and aspects are also disclosed.

  13. Photovoltaic engineering handbook

    Energy Technology Data Exchange (ETDEWEB)

    Lasnier, F; Ang, T G [Asian Institute of Technolgoy, Bangkok (TH)

    1990-01-01

    The Photovoltaic Engineering Handbook is a comprehensive 'nuts and bolts' guide to photovoltaic technology and systems engineering aimed at engineers and designers in the field. It is the first book to look closely at the practical problems involved in evaluating and setting up a PV power system. The authors' comprehensive insight into the different procedures and decisions that a designer needs to make. The book is unique in its coverage and the technical information is presented in a concise and simple way to enable engineers from a wide range of backgrounds to initiate, assess, analyse and design a PV system. Energy planners making decisions on the most appropriate system for specific needs will also benefit from reading this book. Topics covered include technological processes, including solar cell technology, the photovoltaic generator, photovoltaic systems engineering; characterization and testing methods, sizing procedure; economic analysis and instrumentation. (author).

  14. Photonic Design for Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Kosten, E.; Callahan, D.; Horowitz, K.; Pala, R.; Atwater, H.

    2014-08-28

    We describe photonic design approaches for silicon photovoltaics including i) trapezoidal broadband light trapping structures ii) broadband light trapping with photonic crystal superlattices iii) III-V/Si nanowire arrays designed for broadband light trapping.

  15. based gel polymer electrolytes

    Indian Academy of Sciences (India)

    (PVdF) as a host polymer, lithium perchlorate (LiClO4), lithium triflate ... TG/DTA studies showed the thermal stability of the polymer electrolytes. .... are observed while comparing pure XRD spectra with .... batteries as its operating temperature is normally in the .... chain ion movements and the conductivity of the polymer.

  16. Underscreening in concentrated electrolytes.

    Science.gov (United States)

    Lee, Alpha A; Perez-Martinez, Carla S; Smith, Alexander M; Perkin, Susan

    2017-07-01

    Screening of a surface charge by an electrolyte and the resulting interaction energy between charged objects is of fundamental importance in scenarios from bio-molecular interactions to energy storage. The conventional wisdom is that the interaction energy decays exponentially with object separation and the decay length is a decreasing function of ion concentration; the interaction is thus negligible in a concentrated electrolyte. Contrary to this conventional wisdom, we have shown by surface force measurements that the decay length is an increasing function of ion concentration and Bjerrum length for concentrated electrolytes. In this paper we report surface force measurements to test directly the scaling of the screening length with Bjerrum length. Furthermore, we identify a relationship between the concentration dependence of this screening length and empirical measurements of activity coefficient and differential capacitance. The dependence of the screening length on the ion concentration and the Bjerrum length can be explained by a simple scaling conjecture based on the physical intuition that solvent molecules, rather than ions, are charge carriers in a concentrated electrolyte.

  17. Photovoltaic energy barometer

    International Nuclear Information System (INIS)

    Anon

    2006-01-01

    The european market showed all of its strength and soundness in 2005. The 2005 installed cells growth could have been even greater if the market had not been continually curbed by a lack of raw materials. Germany remained the leading photovoltaic market in the world in 2005, positioned far ahead of Japan and the USA. This unabashed success inspired both Spain and Italy, which set up conditions in order to rapidly develop their photovoltaic sectors. (A.L.B.)

  18. Special issue photovoltaic

    International Nuclear Information System (INIS)

    2004-01-01

    In this letter of the INES (french National Institute of the Solar Energy), a special interest is given to photovoltaic realizations in Europe. Many information are provided on different topics: the China future fifth world producer of cells in 2005, batteries and hydrogen to storage the solar energy and a technical sheet on a photovoltaic autonomous site installation for electric power production. (A.L.B.)

  19. Semiconductor Physical Electronics

    CERN Document Server

    Li, Sheng

    2006-01-01

    Semiconductor Physical Electronics, Second Edition, provides comprehensive coverage of fundamental semiconductor physics that is essential to an understanding of the physical and operational principles of a wide variety of semiconductor electronic and optoelectronic devices. This text presents a unified and balanced treatment of the physics, characterization, and applications of semiconductor materials and devices for physicists and material scientists who need further exposure to semiconductor and photonic devices, and for device engineers who need additional background on the underlying physical principles. This updated and revised second edition reflects advances in semicondutor technologies over the past decade, including many new semiconductor devices that have emerged and entered into the marketplace. It is suitable for graduate students in electrical engineering, materials science, physics, and chemical engineering, and as a general reference for processing and device engineers working in the semicondi...

  20. Photovoltaic effect and photopolarization in Pb [(Mg1/3Nb2/3) 0.68Ti0.32] O3 crystal

    Science.gov (United States)

    Makhort, A. S.; Chevrier, F.; Kundys, D.; Doudin, B.; Kundys, B.

    2018-01-01

    Ferroelectric materials are an alternative to semiconductor-based photovoltaics and offer the advantage of above bandgap photovoltage generation. However, there are few known compounds, and photovoltaic efficiencies remain low. Here, we report the discovery of a photovoltaic effect in undoped lead magnesium niobate-lead titanate crystal and a significant improvement in the photovoltaic response under suitable electric fields and temperatures. The photovoltaic effect is maximum near the electric-field-driven ferroelectric dipole reorientation, and increases threefold near the Curie temperature (Tc). Moreover, at ferroelectric saturation, the photovoltaic response exhibits clear remanent and transient effects. The transient-remanent combinations together with electric and thermal tuning possibilities indicate photoferroelectric crystals as emerging elements for photovoltaics and optoelectronics, relevant to all-optical information storage and beyond.

  1. Customized color patterning of photovoltaic cells

    Science.gov (United States)

    Cruz-Campa, Jose Luis; Nielson, Gregory N.; Okandan, Murat; Lentine, Anthony L.; Resnick, Paul J.; Gupta, Vipin P.

    2016-11-15

    Photovoltaic cells and photovoltaic modules, as well as methods of making and using such photovoltaic cells and photovoltaic modules, are disclosed. More particularly, embodiments of the photovoltaic cells selectively reflect visible light to provide the photovoltaic cells with a colorized appearance. Photovoltaic modules combining colorized photovoltaic cells may be used to harvest solar energy while providing a customized appearance, e.g., an image or pattern.

  2. Investigations of Photovoltaic Ferroelectric-Semiconductor Nonvolatile Memory.

    Science.gov (United States)

    1981-03-01

    HEWLETT-PACKARD BOX 3310 100 MARKET ST APT 1 3404 EAST HARMONY RD2U ATTN J. M. KIRSCH, MTS ATTN R. SCHAEFER ATTN L. W. JAMES, MTS FULLERTON, CA 92633...RADIO SYS SPERRY UNICORN 1300 S ROGERS 367 ORCHARD STREET 52-21 65 PL AT’rN J. F. PRATHER, MGR CEN ATTN I. A. PAULL, ES ATTN W. BURSTEIN, ENGR

  3. Photovoltaic mounting/demounting unit

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a photovoltaic arrangement comprising a photovoltaic assembly comprising a support structure defining a mounting surface onto which a photovoltaic module is detachably mounted; and a mounting/demounting unit comprising at least one mounting/demounting apparatus...... which when the mounting/demounting unit is moved along the mounting surface, causes the photovoltaic module to be mounted or demounted to the support structure; wherein the photovoltaic module comprises a carrier foil and wherein a total thickness of the photo voltaic module is below 500 muiotaeta....... The present invention further relates to an associated method for mounting/demounting photovoltaic modules....

  4. Contacts to semiconductors

    International Nuclear Information System (INIS)

    Tove, P.A.

    1975-08-01

    Contacts to semiconductors play an important role in most semiconductor devices. These devices range from microelectronics to power components, from high-sensitivity light or radiation detectors to light-emitting of microwave-generating components. Silicon is the dominating material but compound semiconductors are increasing in importance. The following survey is an attempt to classify contact properties and the physical mechanisms involved, as well as fabrication methods and methods of investigation. The main interest is in metal-semiconductor type contacts where a few basic concepts are dealt with in some detail. (Auth.)

  5. Semiconductor Electrical Measurements Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Semiconductor Electrical Measurements Laboratory is a research laboratory which complements the Optical Measurements Laboratory. The laboratory provides for Hall...

  6. Inrush Transient Current Analysis and Suppression of Photovoltaic Grid-Connected Inverters During Voltage Sag

    DEFF Research Database (Denmark)

    Li, Zhongyu; Zhao, Rende; Xin, Zhen

    2016-01-01

    The Inrush Transient Current (ITC) in the output of the photovoltaic grid-connected inverters is usually generated when grid voltage sag occurs, which can trigger the protection of the grid-connected inverters, and even destroy the semiconductor switches. Then, the grid-connected inverters...

  7. Novel Approach to Front Contact Passivation for CdTe Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Kephart, Jason

    2018-02-18

    The goal of this project was to study the use of sputter-deposited oxide materials for interface passivation of CdTe-based photovoltaics. Several candidate materials were chosen based on their promise in passivating the CdTe and CdSeTe semiconductor interface, chemical and thermal stability to device processing, and ability to be deposited by sputter deposition.

  8. Development of InAlAs Top Cell for High Specific Power Multijunction Photovoltaics

    Data.gov (United States)

    National Aeronautics and Space Administration — The semiconductor material InAlAs has the potential to improve upon current space photovoltaics in a number of ways. InAlAsSb lattice-matched to InP would operate as...

  9. Gel polymer electrolytes for batteries

    Science.gov (United States)

    Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

    2014-11-18

    Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

  10. Ultrafast dynamics and laser action of organic semiconductors

    CERN Document Server

    Vardeny, Zeev Valy

    2009-01-01

    Spurred on by extensive research in recent years, organic semiconductors are now used in an array of areas, such as organic light emitting diodes (OLEDs), photovoltaics, and other optoelectronics. In all of these novel applications, the photoexcitations in organic semiconductors play a vital role. Exploring the early stages of photoexcitations that follow photon absorption, Ultrafast Dynamics and Laser Action of Organic Semiconductors presents the latest research investigations on photoexcitation ultrafast dynamics and laser action in pi-conjugated polymer films, solutions, and microcavities.In the first few chapters, the book examines the interplay of charge (polarons) and neutral (excitons) photoexcitations in pi-conjugated polymers, oligomers, and molecular crystals in the time domain of 100 fs-2 ns. Summarizing the state of the art in lasing, the final chapters introduce the phenomenon of laser action in organics and cover the latest optoelectronic applications that use lasing based on a variety of caviti...

  11. Thin Film Photovoltaic Partnership Project | Photovoltaic Research | NREL

    Science.gov (United States)

    Thin Film Photovoltaic Partnership Project Thin Film Photovoltaic Partnership Project NREL's Thin Film Photovoltaic (PV) Partnership Project led R&D on emerging thin-film solar technologies in the United States from 1994 to 2009. The project made many advances in thin-film PV technologies that allowed

  12. Sodium conducting polymer electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Skaarup, S.; West, K. (eds.)

    1989-04-01

    This section deals with the aspects of ionic conduction in general as well as specific experimental results obtained for sodium systems. The conductivity as a function of temperature and oxygen/metal ratio are given for the systems NaI, NaCF/sub 3/SO/sub 3/ and NaClO/sub 4/ plus polyethylene oxide. Attempts have been made to produce mixed phase solid electrolytes analogous to the lithium systems that have worked well. These consist of mixtures of polymer and a solid electrolyte. The addition of both nasicon and sodium beta alumina unexpectedly decreases the ionic conductivity in contrast to the lithium systems. Addition of the nonconducting silica AEROSIL in order to increase the internal surface area has the effect of retarding the phase transition at 60 deg. C, but does not enhance the conductivity. (author) 23 refs.

  13. Nanoporous hybrid electrolytes

    KAUST Repository

    Schaefer, Jennifer L.

    2011-01-01

    Oligomer-suspended SiO2-polyethylene glycol nanoparticles are studied as porous media electrolytes. At SiO2 volume fractions, , bracketing a critical value y ≈ 0.29, the suspensions jam and their mechanical modulus increase by more than seven orders. For >y, the mean pore diameter is close to the anion size, yet the ionic conductivity remains surprisingly high and can be understood, at all , using a simple effective medium model proposed by Maxwell. SiO 2-polyethylene glycol hybrid electrolytes are also reported to manifest attractive electrochemical stability windows (0.3-6.3 V) and to reach a steady-state interfacial impedance when in contact with metallic lithium. © 2010 The Royal Society of Chemistry.

  14. Nanostructured Photovoltaics for Space Power

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA NSTRF proposal entitled Nanostructured Photovoltaics for Space Power is targeted towards research to improve the current state of the art photovoltaic...

  15. Conductometry of electrolyte solutions

    Science.gov (United States)

    Safonova, Lyubov P.; Kolker, Arkadii M.

    1992-09-01

    A review is given of the theories of the electrical conductance of electrolyte solutions of different ionic strengths and concentrations, and of the models of ion association. An analysis is made of the methods for mathematical processing of experimental conductometric data. An account is provided of various theories describing the dependence of the limiting value of the ionic electrical conductance on the properties of the solute and solvent. The bibliography includes 115 references.

  16. Solid polymer electrolytes

    Science.gov (United States)

    Abraham, Kuzhikalail M.; Alamgir, Mohamed; Choe, Hyoun S.

    1995-01-01

    This invention relates to Li ion (Li.sup.+) conductive solid polymer electrolytes composed of poly(vinyl sulfone) and lithium salts, and their use in all-solid-state rechargeable lithium ion batteries. The lithium salts comprise low lattice energy lithium salts such as LiN(CF.sub.3 SO.sub.2).sub.2, LiAsF.sub.6, and LiClO.sub.4.

  17. Electrolyte Concentrates Treat Dehydration

    Science.gov (United States)

    2009-01-01

    Wellness Brands Inc. of Boulder, Colorado, exclusively licensed a unique electrolyte concentrate formula developed by Ames Research Center to treat and prevent dehydration in astronauts returning to Earth. Marketed as The Right Stuff, the company's NASA-derived formula is an ideal measure for athletes looking to combat dehydration and boost performance. Wellness Brands also plans to expand with products that make use of the formula's effective hydration properties to help treat conditions including heat stroke, altitude sickness, jet lag, and disease.

  18. Electrochemical polymer electrolyte membranes

    CERN Document Server

    Fang, Jianhua; Wilkinson, David P

    2015-01-01

    Electrochemical Polymer Electrolyte Membranes covers PEMs from fundamentals to applications, describing their structure, properties, characterization, synthesis, and use in electrochemical energy storage and solar energy conversion technologies. Featuring chapters authored by leading experts from academia and industry, this authoritative text: Discusses cutting-edge methodologies in PEM material selection and fabricationPoints out important challenges in developing PEMs and recommends mitigation strategies to improve PEM performanceAnalyzes the cur

  19. Semiconductors data handbook

    CERN Document Server

    Madelung, Otfried

    2004-01-01

    This volume Semiconductors: Data Handbook contains frequently used data from the corresponding larger Landolt-Börnstein handbooks in a low price book for the individual scientist working in the laboratory. The Handbook contain important information about a large number of semiconductors

  20. Semiconductor radiation detection systems

    CERN Document Server

    2010-01-01

    Covers research in semiconductor detector and integrated circuit design in the context of medical imaging using ionizing radiation. This book explores other applications of semiconductor radiation detection systems in security applications such as luggage scanning, dirty bomb detection and border control.

  1. Spin physics in semiconductors

    CERN Document Server

    Dyakonov, Mikhail I

    2008-01-01

    This book describes beautiful optical and transport phenomena related to the electron and nuclear spins in semiconductors with emphasis on a clear presentation of the physics involved. Recent results on quantum wells and quantum dots are reviewed. The book is intended for students and researchers in the fields of semiconductor physics and nanoelectronics.

  2. Semiconductor relay and its manufacture method. Handotai relay oyobi sono seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, M

    1993-06-01

    The invention relates to a semiconductor relay in which a light emitting diode and a photovoltaic element are arranged in the opposite positions and connected with a light connection and aims to present a light transmission path to transmit input signals to the light emitting diode to the side of the photovoltaic element with a negligible light loss effectively. The invention presents a semiconductor relay, in which a light emitting diode loaded on the first lead frame and the light receiving part of the photovoltaic element to drive a MOSFET element loaded on the second lead frame and acting as a switch element are connected through an insulator tube with an opaque outer wall, and the interior of the insulator tube is filled with a transparent insulating filler, so that the invention affords a light transmission path without light leakage from the interior of the opaque insulator tube and with the stability in the form and no light loss. 3 figs.

  3. Can photovoltaic replace nuclear?

    International Nuclear Information System (INIS)

    2017-01-01

    As the French law on energy transition for a green growth predicts that one third of nuclear energy production is to be replaced by renewable energies (wind and solar) by 2025, and while the ADEME proposes a 100 per cent renewable scenario for 2050, this paper proposes a brief analysis of the replacement of nuclear energy by solar photovoltaic energy. It presents and discusses some characteristics of photovoltaic production: production level during a typical day for each month (a noticeable lower production in December), evolution of monthly production during a year, evolution of the rate between nuclear and photovoltaic production. A cost assessment is then proposed for energy storage and for energy production, and a minimum cost of replacement of nuclear by photovoltaic is assessed. The seasonal effect is outlined, as well as the latitude effect. Finally, the authors outline the huge cost of such a replacement, and consider that public support to new photovoltaic installations without an at least daily storage mean should be cancelled

  4. International Photovoltaic Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    Costello, D.; Koontz, R.; Posner, D.; Heiferling, P.; Carpenter, P.; Forman, S.; Perelman, L.

    1979-12-01

    The International Photovoltaics Program Plan is in direct response to the Solar Photovoltaic Energy Research, Development, and Demonstration Act of 1978 (PL 95-590). As stated in the Act, the primary objective of the plan is to accelerate the widespread use of photovoltaic systems in international markets. Benefits which could result from increased international sales by US companies include: stabilization and expansion of the US photovoltaic industry, preparing the industry for supplying future domestic needs; contribution to the economic and social advancement of developing countries; reduced world demand for oil; and improvements in the US balance of trade. The plan outlines programs for photovoltaic demonstrations, systems developments, supplier assistance, information dissemination/purchaser assistance, and an informaion clearinghouse. Each program element includes tactical objectives and summaries of approaches. A program management office will be established to coordinate and manage the program plan. Although the US Department of Energy (DOE) had the lead responsibility for preparing and implementing the plan, numerous federal organizations and agencies (US Departments of Commerce, Justice, State, Treasury; Agency for International Development; ACTION; Export/Import Bank; Federal Trade Commission; Small Business Administration) were involved in the plan's preparation and implementation.

  5. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  6. Terahertz semiconductor nonlinear optics

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias

    2013-01-01

    In this proceedings we describe our recent results on semiconductor nonlinear optics, investigated using single-cycle THz pulses. We demonstrate the nonlinear absorption and self-phase modulation of strong-field THz pulses in doped semiconductors, using n-GaAs as a model system. The THz...... nonlinearity in doped semiconductors originates from the near-instantaneous heating of free electrons in the ponderomotive potential created by electric field of the THz pulse, leading to ultrafast increase of electron effective mass by intervalley scattering. Modification of effective mass in turn leads...... to a decrease of plasma frequency in semiconductor and produces a substantial modification of THz-range material dielectric function, described by the Drude model. As a result, the nonlinearity of both absorption coefficient and refractive index of the semiconductor is observed. In particular we demonstrate...

  7. Electrolyte materials - Issues and challenges

    International Nuclear Information System (INIS)

    Balbuena, Perla B.

    2014-01-01

    Electrolytes are vital components of an electrochemical energy storage device. They are usually composed of a solvent or mixture of solvents and a salt or a mixture of salts which provide the appropriate environment for ionic conduction. One of the main issues associated with the selection of a proper electrolyte is that its electronic properties have to be such that allow a wide electrochemical window - defined as the voltage range in which the electrolyte is not oxidized or reduced - suitable to the battery operating voltage. In addition, electrolytes must have high ionic conductivity and negligible electronic conductivity, be chemically stable with respect to the other battery components, have low flammability, and low cost. Weak stability of the electrolyte against oxidation or reduction leads to the formation of a solid-electrolyte interphase (SEI) layer at the surface of the cathode and anode respectively. Depending on the materials of the electrolyte and those of the electrode, the SEI layer may be composed by combinations of organic and inorganic species, and it may exert a passivating role. In this paper we discuss the current status of knowledge about electrolyte materials, including non-aqueous liquids, ionic liquids, solid ceramic and polymer electrolytes. We also review the basic knowledge about the SEI layer formation, and challenges for a rational design of stable electrolytes

  8. Photovoltaic Subcontract Program

    Energy Technology Data Exchange (ETDEWEB)

    Surek, Thomas; Catalano, Anthony

    1993-03-01

    This report summarizes the fiscal year (FY) 1992 progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL)-formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Crystalline Materials and Advanced Concepts project, the Polycrystalline Thin Films project, Amorphous Silicon Research project, the Photovoltaic Manufacturing Technology (PVMaT) project, PV Module and System Performance and Engineering project, and the PV Analysis and Applications Development project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1992, and future research directions.

  9. Photovoltaic programme - edition 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This publication issued by the Swiss Federal Office of Energy's Photovoltaics (PV) Programme presents an overview (in English) of activities and projects in the photovoltaics research and pilot and demonstration area in Switzerland. Progress in the area of future solar cell technologies, modules and building integration, system technologies, planning and operating aids is summarised. Also, PV for applications in developing countries, thermo-photovoltaics and international co-operation are commented on. In the area of pilot and demonstration projects, component development, PV integration in sloping roofs, on flat roofs and noise barriers as well as further PV plant are looked at. Also, measurement campaigns, studies, statistics and further PV-related topics are summarised. This volume also presents the abstracts of reports made by the project managers of 73 research and pilot and demonstration projects in these areas for 2002.

  10. Photovoltaic barometer; Barometre photovoltaique

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-04-15

    The photovoltaic sector is continuing on track, just as the extent of solar energy's electricity-generating potential is dawning on the public mind. The annual global installation figure was up more than twofold in 2010 (rising from just short of 7000 MWp in 2009). It leapt to over 16000 MWp, bringing worldwide installed photovoltaic capacity close to 38000 MWp. The photovoltaic power generated in the European Union at the end of 2010 reached 22.5 TWh which means an additional capacity of 13023 MWp during 2010. Concerning the cumulated installed capacity, Germany and Spain rank first and second in the European Union with respectively 17370 MWp and 3808 MWp

  11. The 2009 photovoltaic barometer

    International Nuclear Information System (INIS)

    Anon.

    2010-01-01

    The global photovoltaic market expanded again in 2009. Germany set a new system installation record while the capacity build-up of the major solar photovoltaic markets contained the fallout generated by the Iberian market derailment. The European Union has the highest photovoltaic plant capacity, with almost 5.5 GWp installed in 2009. Italy is the third European Union country to pass the symbolic 1000 MWp installed mark, following Germany and Spain. France ranks 6 with 185 MWp installed in 2009. The decrease in the price of silicon reached 80% in 2009. The industry is facing a coming-of-age crisis with prices falling and over-production. Most of the major cell manufacturers are located in Asia. The European industry is still well represented with Q-Cells, the German leading cell manufacturer in addition with hefty industry players. (A.C.)

  12. Photovoltaic policy is questioned

    International Nuclear Information System (INIS)

    Piro, P.; Cessac, M.

    2011-01-01

    The French government has decided a freeze and a reassessment of the measures taken to support the photovoltaic sector. Only the installations with a power output over 3 kWc are concerned so the market of solar roofs for homes is spared. The main reasons for this reversal is the quick and chaotic development of photovoltaic projects, a lot of projects are only motivated by the lure of high purchase prices of the electricity produced imposed by the law on EDF. Another reason is that 90% of the solar panels installed in France come from China, the photovoltaic sector retorts that 75% of the price of a complete installation pays for services produced in France. (A.C.)

  13. Photovoltaic programme - edition 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This publication issued by the Swiss Federal Office of Energy's Photovoltaics (PV) Programme presents an overview (in English) of activities and projects in the photovoltaics research and pilot and demonstration area in Switzerland. Progress in the area of future solar cell technologies, modules and building integration, system technologies, planning and operating aids is summarised. Also, PV for applications in developing countries, thermo-photovoltaics and international co-operation are commented on. In the area of pilot and demonstration projects, component development, PV integration in sloping roofs, on flat roofs and noise barriers as well as further PV plant are looked at. Also, measurement campaigns, studies, statistics and further PV-related topics are summarised. This volume also presents the abstracts of reports made by the project managers of 73 research and pilot and demonstration projects in these areas for 2002.

  14. Fabrication of Monolithic Dye-Sensitized Solar Cell Using Ionic Liquid Electrolyte

    Directory of Open Access Journals (Sweden)

    Seigo Ito

    2012-01-01

    Full Text Available To improve the durability of dye-sensitized solar cells (DSCs, monolithic DSCs with ionic liquid electrolyte were studied. Deposited by screen printing, a carbon layer was successfully fabricated that did not crack or peel when annealing was employed beforehand. Optimized electrodes exhibited photovoltaic characteristics of 0.608 V open-circuit voltage, 6.90 cm−2 mA short-circuit current, and 0.491 fill factor, yielding 2.06% power conversion efficiency. The monolithic DSC using ionic liquid electrolyte was thermally durable and operated stably for 1000 h at 80°C.

  15. Concentrating photovoltaic solar panel

    Science.gov (United States)

    Cashion, Steven A; Bowser, Michael R; Farrelly, Mark B; Hines, Braden E; Holmes, Howard C; Johnson, Jr., Richard L; Russell, Richard J; Turk, Michael F

    2014-04-15

    The present invention relates to photovoltaic power systems, photovoltaic concentrator modules, and related methods. In particular, the present invention features concentrator modules having interior points of attachment for an articulating mechanism and/or an articulating mechanism that has a unique arrangement of chassis members so as to isolate bending, etc. from being transferred among the chassis members. The present invention also features adjustable solar panel mounting features and/or mounting features with two or more degrees of freedom. The present invention also features a mechanical fastener for secondary optics in a concentrator module.

  16. Photovoltaics and the environment

    International Nuclear Information System (INIS)

    Baumann, A.E.

    1994-01-01

    This paper considers the impact of photovoltaics on the environment and its application and role in the energy supply sector. It discusses the environmental and health impacts associated with photovoltaics by using Life Cycle Analysis as an instrument to determine its environmental effects. Recent Life Cycle studies have shown that PV can be considered an environmentally low risk technology, with its major environmental impacts occurring at the module manufacturing and waste disposal stages. The employment of environmental control mechanisms and statutory health and safety regulations at PV production facilities have helped to further reduce occupational and public health hazards. (author)

  17. Photovoltaic demonstration projects 2

    Energy Technology Data Exchange (ETDEWEB)

    Gillett, W B; Hacker, R J [Halcrow (William) and Partners, Swindon (UK); Kaut, W [eds.

    1989-01-01

    This book, the proceedings of the third Photovoltaic Contractors' Meeting organised by the Commission of the European Communities, Directorate-General for Energy provides an overview of the photovoltaic demonstration projects which have been supported by the Energy Directorate of the Commission of the European Communities since 1983. It includes reports by each of the contractors who submitted proposals in 1983, 1984 and 1985, describing progress with their projects. The different technologies which are being demonstrated concern the modules, the cabling of the array, structure design, storage strategy and power conditioning. The various applications include powering of houses, villages, recreation centres, water desalination, communications, dairy farms, water pumping and warning systems. (author).

  18. Photovoltaic roofing tile systems

    Science.gov (United States)

    Melchior, B.

    The integration of photovoltaic (PV) systems in architecture is discussed. A PV-solar roofing tile system with polymer concrete base; PV-roofing tile with elastomer frame profiles and aluminum profile frames; contact technique; and solar cell modules measuring technique are described. Field tests at several places were conducted on the solar generator, electric current behavior, battery station, electric installation, power conditioner, solar measuring system with magnetic bubble memory technique, data transmission via telephone modems, and data processing system. The very favorable response to the PV-compact system proves the commercial possibilities of photovoltaic integration in architecture.

  19. Distributed photovoltaic grid transformers

    CERN Document Server

    Shertukde, Hemchandra Madhusudan

    2014-01-01

    The demand for alternative energy sources fuels the need for electric power and controls engineers to possess a practical understanding of transformers suitable for solar energy. Meeting that need, Distributed Photovoltaic Grid Transformers begins by explaining the basic theory behind transformers in the solar power arena, and then progresses to describe the development, manufacture, and sale of distributed photovoltaic (PV) grid transformers, which help boost the electric DC voltage (generally at 30 volts) harnessed by a PV panel to a higher level (generally at 115 volts or higher) once it is

  20. Recovering valuable metals from recycled photovoltaic modules.

    Science.gov (United States)

    Yi, Youn Kyu; Kim, Hyun Soo; Tran, Tam; Hong, Sung Kil; Kim, Myong Jun

    2014-07-01

    Recovering valuable metals such as Si, Ag, Cu, and Al has become a pressing issue as end-of-life photovoltaic modules need to be recycled in the near future to meet legislative requirements in most countries. Of major interest is the recovery and recycling of high-purity silicon (> 99.9%) for the production of wafers and semiconductors. The value of Si in crystalline-type photovoltaic modules is estimated to be -$95/kW at the 2012 metal price. At the current installed capacity of 30 GW/yr, the metal value in the PV modules represents valuable resources that should be recovered in the future. The recycling of end-of-life photovoltaic modules would supply > 88,000 and 207,000 tpa Si by 2040 and 2050, respectively. This represents more than 50% of the required Si for module fabrication. Experimental testwork on crystalline Si modules could recover a > 99.98%-grade Si product by HNO3/NaOH leaching to remove Al, Ag, and Ti and other metal ions from the doped Si. A further pyrometallurgical smelting at 1520 degrees C using CaO-CaF2-SiO2 slag mixture to scavenge the residual metals after acid leaching could finally produce > 99.998%-grade Si. A process based on HNO3/NaOH leaching and subsequent smelting is proposed for recycling Si from rejected or recycled photovoltaic modules. Implications: The photovoltaic industry is considering options of recycling PV modules to recover metals such as Si, Ag, Cu, Al, and others used in the manufacturing of the PV cells. This is to retain its "green" image and to comply with current legislations in several countries. An evaluation of potential resources made available from PV wastes and the technologies used for processing these materials is therefore of significant importance to the industry. Of interest are the costs of processing and the potential revenues gained from recycling, which should determine the viability of economic recycling of PV modules in the future.

  1. Road map for photovoltaic electricity

    International Nuclear Information System (INIS)

    2011-02-01

    This road map aims at highlighting industrial, technological and social challenges, at elaborating comprehensive visions, at highlighting technological locks, and at outlining research needs for the photovoltaic sector. It considers the following sector components: preparation of photo-sensitive materials, manufacturing of photovoltaic cells, manufacturing of photovoltaic arrays, design and manufacturing of electric equipment to control photovoltaic arrays and to connect them to the grid. It highlights the demand for photovoltaic installations, analyzes the value chain, proposes a vision of the sector by 2050 and defines target for 2020, discusses needs for demonstration and experimentation

  2. Nanostructured TiO2 microspheres for dye-sensitized solar cells employing a solid state polymer electrolyte

    International Nuclear Information System (INIS)

    Jung, Hun-Gi; Nagarajan, Srinivasan; Kang, Yong Soo; Sun, Yang-Kook

    2013-01-01

    Bimodal mesoporous, anatase TiO 2 microspheres with particle sizes ranging from 0.3 to 2 μm were synthesized using a facile solvothermal method. The photovoltaic performance of TiO 2 microspheres in dye-sensitized solar cells (DSSCs) using a solid state electrolyte was investigated. The solid state electrolyte DSSC device based on the TiO 2 microspheres exhibits an energy conversion efficiency of 4.2%, which is greater than that of commercial P25 TiO 2 (3.6%). The higher photocurrent density was primarily achieved as a result of the greater specific surface area and pore size, which resulted in an increase in the dye uptake of the TiO 2 microspheres and easy transport of solid electrolyte through mesopores. In addition, the greater electron lifetime and superior light scattering ability also enhanced the photovoltaic performance of the TiO 2 microsphere-based, solid state DSSCs

  3. Defects in semiconductors

    International Nuclear Information System (INIS)

    Pimentel, C.A.F.

    1983-01-01

    Some problems openned in the study of defects in semiconductors are presented. In particular, a review is made of the more important problems in Si monocrystals of basic and technological interest: microdefects and the presence of oxigen and carbon. The techniques usually utilized in the semiconductor material characterization are emphatized according its potentialities. Some applications of x-ray techniques in the epitaxial shell characterization in heterostructures, importants in electronic optics, are shown. The increase in the efficiency of these defect analysis methods in semiconductor materials with the use of synchrotron x-ray sources is shown. (L.C.) [pt

  4. Introduction to Semiconductor Devices

    Science.gov (United States)

    Brennan, Kevin F.

    2005-03-01

    This volume offers a solid foundation for understanding the most important devices used in the hottest areas of electronic engineering today, from semiconductor fundamentals to state-of-the-art semiconductor devices in the telecommunications and computing industries. Kevin Brennan describes future approaches to computing hardware and RF power amplifiers, and explains how emerging trends and system demands of computing and telecommunications systems influence the choice, design and operation of semiconductor devices. In addition, he covers MODFETs and MOSFETs, short channel effects, and the challenges faced by continuing miniaturization. His book is both an excellent senior/graduate text and a valuable reference for practicing engineers and researchers.

  5. Spin physics in semiconductors

    CERN Document Server

    2017-01-01

    This book offers an extensive introduction to the extremely rich and intriguing field of spin-related phenomena in semiconductors. In this second edition, all chapters have been updated to include the latest experimental and theoretical research. Furthermore, it covers the entire field: bulk semiconductors, two-dimensional semiconductor structures, quantum dots, optical and electric effects, spin-related effects, electron-nuclei spin interactions, Spin Hall effect, spin torques, etc. Thanks to its self-contained style, the book is ideally suited for graduate students and researchers new to the field.

  6. Physics of semiconductor lasers

    CERN Document Server

    Mroziewicz, B; Nakwaski, W

    2013-01-01

    Written for readers who have some background in solid state physics but do not necessarily possess any knowledge of semiconductor lasers, this book provides a comprehensive and concise account of fundamental semiconductor laser physics, technology and properties. The principles of operation of these lasers are therefore discussed in detail with the interrelations between their design and optical, electrical and thermal properties. The relative merits of a large number of laser structures and their parameters are described to acquaint the reader with the various aspects of the semiconductor l

  7. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  8. Defects in semiconductors

    CERN Document Server

    Romano, Lucia; Jagadish, Chennupati

    2015-01-01

    This volume, number 91 in the Semiconductor and Semimetals series, focuses on defects in semiconductors. Defects in semiconductors help to explain several phenomena, from diffusion to getter, and to draw theories on materials' behavior in response to electrical or mechanical fields. The volume includes chapters focusing specifically on electron and proton irradiation of silicon, point defects in zinc oxide and gallium nitride, ion implantation defects and shallow junctions in silicon and germanium, and much more. It will help support students and scientists in their experimental and theoret

  9. Application of Composite Polymer Electrolytes

    National Research Council Canada - National Science Library

    Scrosati, Bruno

    2001-01-01

    ...)PEO-based composite polymer electrolytes, by a series of specifically addressed electrochemical tests which included the determination of the conductivity and of the lithium transference number...

  10. Solid state electrolyte systems

    Energy Technology Data Exchange (ETDEWEB)

    Pederson, L.R.; Armstrong, B.L.; Armstrong, T.R. [Pacific Northwest Lab., Richland, WA (United States)] [and others

    1997-12-01

    Lanthanum gallates are a new family of solid electrolytes that exhibit high ionic conductivity and are stable to high temperatures. Compositions have been developed that are as much as a factor of two more conductive than yttria-stabilized zirconia at a given temperature, through partial replacement of lanthanum by calcium, strontium, and/or barium and through partial replacement of gallium by magnesium. Oxide powders were prepared using combustion synthesis techniques developed in this laboratory; these were sintered to >95% of theoretical density and consisted of a single crystalline phase. Electrical conductivities, electron and ion transference numbers, thermal expansion, and phase behavior were evaluated as a function of temperature and oxygen partial pressure. A key advantage of the use of lanthanum gallate electrolytes in solid oxide fuel cells is that the temperature of operation may be lowered to perhaps 800 C, yet provide approximately the same power density as zirconia-based cells operating at 1000 C. Ceramic electrolytes that conduct both oxygen ions and electrons are potentially useful to passively separate pure oxygen from an air source at low cost. In such materials, an oxygen ion flux in one direction is charge-compensated by an opposing electron flux. The authors have examined a wide range of mixed ion and electron conducting perovskite ceramics in the system La{sub 1{minus}x}M{sub x}Co{sub 1{minus}y{minus}z}Fe{sub y}N{sub z}O{sub 3{minus}{delta}}, where M = Sr, Ca, and Ba, and N = Pr, Mn, Ni, Cu, Ti, and Al, as well as mixed conducting brownmillerite ceramics, and have characterized oxygen permeation behavior, defect chemistry, structural and phase stability, and performance as cathodes.

  11. Progress in piezo-phototronic effect modulated photovoltaics.

    Science.gov (United States)

    Que, Miaoling; Zhou, Ranran; Wang, Xiandi; Yuan, Zuqing; Hu, Guofeng; Pan, Caofeng

    2016-11-02

    Wurtzite structured materials, like ZnO, GaN, CdS, and InN, simultaneously possess semiconductor and piezoelectric properties. The inner-crystal piezopotential induced by external strain can effectively tune/control the carrier generation, transport and separation/combination processes at the metal-semiconductor contact or p-n junction, which is called the piezo-phototronic effect. This effect can efficiently enhance the performance of photovoltaic devices based on piezoelectric semiconductor materials by utilizing the piezo-polarization charges at the junction induced by straining, which can modulate the energy band of the piezoelectric material and then accelerate or prevent the separation process of the photon-generated electrons and vacancies. This paper introduces the fundamental physics principles of the piezo-phototronic effect, and reviews recent progress in piezo-phototronic effect enhanced solar cells, including solar cells based on semiconductor nanowire, organic/inorganic materials, quantum dots, and perovskite. The piezo-phototronic effect is suggested as a suitable basis for the development of an innovative method to enhance the performance of solar cells based on piezoelectric semiconductors by applied extrinsic strains, which might be appropriate for fundamental research and potential applications in various areas of optoelectronics.

  12. Solar photovoltaic markets, economics, technology, and potential

    Energy Technology Data Exchange (ETDEWEB)

    Blais, J.M.J.; Molinski, T.S. [Manitoba Hydro, Winnipeg, MB (Canada)]|[Emerging Energy Systems, Islamabad (Pakistan)

    2008-07-01

    Solar Photovoltaics (PV) are solid state semiconductor electronic devices that transform infrared, visible, or ultraviolet light energy from the sun directly into electrical energy. Selenium was used to create the first solar cell in 1883. In 1954, Bell Laboratories developed the modern day silicon solar cell, whereby impurities were added to silicon through a process called doping. Silicon doped with boron results in a positive electrical charge, while silicon doped with phosphorous results in a negative electrical charge. The atom collision from photons in sunlight provides the necessary energy to free a trapped electron in the doped silicon, which then may flow through a wire creating an electric current. Many different materials besides silicon are used to create solar cells, such as plastics, organic compounds, and theoretically even special paints, while other doping agents besides boron and phosphorous are also used, such as arsenic and gallium. This paper provided an introduction to solar PV and world solar PV growth and markets. A review of solar PV economics was also included. In 2008, the total installed costs of solar photovoltaic cells were in the range of 7 to 10 Canadian dollars. In addition, the advantages and disadvantages of solar PV were presented. Solar technologies under research and development were also discussed and assessed. It was concluded that although solar PV was one of the most expensive forms of renewable generation, there is great potential for solar PV to gain broader based application as costs continue to drop. 11 refs., 1 tab., 1 fig.

  13. Devices and optics for photovoltaic conversion

    International Nuclear Information System (INIS)

    Arujo, G.L.

    1991-01-01

    Photovoltaic energy is one of the most promising renewable energies. The contents of this article deals firstly with the physics of the devices and the optics employed to convert directly sunlight into electricity. Secondly the state of the art of the high efficiency solar cells and concentration systems will be addressed. Finally, there will be some concluding comments about the future prospects of the photovoltaic energy. PV energy conversion is at present a viable technology to produce electricity. But unfortunately its cost is still too high to be competitive with grid connected applications. Roughly speaking there are two main strategies for reducing costs in PV: One of them relies on thin-film, low cost solar cells and modules and the other relies on high efficiency solar cells and modules used, in many cases, in combination with optical concentration. This work will focus in high efficiency solar cells, what means that good quality crystalline semiconductor materials are involved, and in the optics used in concentration systems. 25 figs, 2 tabs

  14. Nanostructured Semiconductor Materials for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Carmen Cavallo

    2017-01-01

    Full Text Available Since O’Regan and Grätzel’s first report in 1991, dye-sensitized solar cells (DSSCs appeared immediately as a promising low-cost photovoltaic technology. In fact, though being far less efficient than conventional silicon-based photovoltaics (being the maximum, lab scale prototype reported efficiency around 13%, the simple design of the device and the absence of the strict and expensive manufacturing processes needed for conventional photovoltaics make them attractive in small-power applications especially in low-light conditions, where they outperform their silicon counterparts. Nanomaterials are at the very heart of DSSC, as the success of its design is due to the use of nanostructures at both the anode and the cathode. In this review, we present the state of the art for both n-type and p-type semiconductors used in the photoelectrodes of DSSCs, showing the evolution of the materials during the 25 years of history of this kind of devices. In the case of p-type semiconductors, also some other energy conversion applications are touched upon.

  15. Autonomous photovoltaic lighting system

    OpenAIRE

    Hafez, Ahmed A. A.; Montesinos Miracle, Daniel; Sudrià Andreu, Antoni

    2012-01-01

    This paper introduces a comparison between the conventional and Photovoltaic (PV) lighting systems. A simple sizing procedure for a PV stand-alone system was advised. The paper also proposes a novel PV lighting system. The proposed system is simple, compact and reliable. The system operation was investigated by thoroughly mathematical and simulation work.

  16. Modelling the Photovoltaic Module

    DEFF Research Database (Denmark)

    Katsanevakis, Markos

    2011-01-01

    This paper refers into various ways in simulation the Photovoltaic (PV) module behaviour under any combination of solar irradiation and ambient temperature. There are three different approaches presented here briefly and one of them is chosen because of its good accuracy and relatively low...

  17. Building integrated photovoltaics

    NARCIS (Netherlands)

    Ritzen, M.J.; Vroon, Z.A.E.P.; Geurts, C.P.W.; Reinders, Angèle; Verlinden, Pierre; Sark, Wilfried; Freundlich, Alexandre

    2017-01-01

    Photovoltaic (PV) installations can be realized in different situations and on different scales, such as at a building level. PV installations at the building level can either be added to the building envelope, which is called building added PV (BAPV), or they can be integrated into the building

  18. Lifetime of organic photovoltaics

    DEFF Research Database (Denmark)

    Corazza, Michael; Krebs, Frederik C; Gevorgyan, Suren A.

    2015-01-01

    tests. Comparison of the indoor and outdoor lifetimes was performed by means of the o-diagram, which constitutes the initial steps towards establishing a method for predicting the lifetime of an organic photovoltaic device under real operational conditions based on a selection of accelerated indoor...

  19. Photovoltaic solar; Solaire photovoltaique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-01-01

    This study aims to observe, from european examples, the local governments policies in matter of the photovoltaic development. This approach is very different for each town. The first part evaluates the initiatives, the second part is devoted to the global situation in Europe and the third part brings recommendations. (A.L.B.)

  20. Photovoltaics technology program summary

    Science.gov (United States)

    1985-05-01

    An adequate supply of energy at reasonable price is discussed. Economic efficiency and the following strategies to obtain it are suggested: (1) minimization of federal regulation in energy pricing; and (2) promote a balanced and mixed energy resource system. The development of photovoltaic energy conversion technology is summarized.

  1. Photovoltaic cell module and method of forming

    Science.gov (United States)

    Howell, Malinda; Juen, Donnie; Ketola, Barry; Tomalia, Mary Kay

    2017-12-12

    A photovoltaic cell module, a photovoltaic array including at least two modules, and a method of forming the module are provided. The module includes a first outermost layer and a photovoltaic cell disposed on the first outermost layer. The module also includes a second outermost layer disposed on the photovoltaic cell and sandwiching the photovoltaic cell between the second outermost layer and the first outermost layer. The method of forming the module includes the steps of disposing the photovoltaic cell on the first outermost layer, disposing a silicone composition on the photovoltaic cell, and compressing the first outermost layer, the photovoltaic cell, and the second layer to form the photovoltaic cell module.

  2. Biggest semiconductor installed

    CERN Multimedia

    2008-01-01

    Scientists and technicians at the European Laboratory for Particle Physics, commonly known by its French acronym CERN (Centre Europen pour la Recherche Nuclaire), have completed the installation of the largest semiconductor silicon detector.

  3. Compact semiconductor lasers

    CERN Document Server

    Yu, Siyuan; Lourtioz, Jean-Michel

    2014-01-01

    This book brings together in a single volume a unique contribution by the top experts around the world in the field of compact semiconductor lasers to provide a comprehensive description and analysis of the current status as well as future directions in the field of micro- and nano-scale semiconductor lasers. It is organized according to the various forms of micro- or nano-laser cavity configurations with each chapter discussing key technical issues, including semiconductor carrier recombination processes and optical gain dynamics, photonic confinement behavior and output coupling mechanisms, carrier transport considerations relevant to the injection process, and emission mode control. Required reading for those working in and researching the area of semiconductors lasers and micro-electronics.

  4. Electrolyte creepage barrier for liquid electrolyte fuel cells

    Science.gov (United States)

    Li, Jian [Alberta, CA; Farooque, Mohammad [Danbury, CT; Yuh, Chao-Yi [New Milford, CT

    2008-01-22

    A dielectric assembly for electrically insulating a manifold or other component from a liquid electrolyte fuel cell stack wherein the dielectric assembly includes a substantially impermeable dielectric member over which electrolyte is able to flow and a barrier adjacent the dielectric member and having a porosity of less than 50% and greater than 10% so that the barrier is able to measurably absorb and chemically react with the liquid electrolyte flowing on the dielectric member to form solid products which are stable in the liquid electrolyte. In this way, the barrier inhibits flow or creepage of electrolyte from the dielectric member to the manifold or component to be electrically insulated from the fuel cell stack by the dielectric assembly.

  5. Electrolytic pretreatment of urine

    Science.gov (United States)

    1977-01-01

    Electrolysis has been under evaluation for several years as a process to pretreat urine for ultimate recovery of potable water in manned spacecraft applications. The conclusions that were drawn from this investigation are the following: (1) A platinum alloy containing 10 percent rhodium has been shown to be an effective, corrosion-resistant anode material for the electrolytic pretreatment of urine. Black platinum has been found to be suitable as a cathode material. (2) The mechanism of the reactions occurring during the electrolysis of urine is two-stage: (a) a total Kjeldahl nitrogen and total organic carbon (TOC) removal in the first stage is the result of electrochemical oxidation of urea to CO2, H2O, and ammonia followed by chloride interaction to produce N2 from ammonia, (b) after the urea has been essentially removed and the chloride ions have no more ammonia to interact with, the chloride ions start to oxidize to higher valence states, thus producing perchlorates. (3) Formation of perchlorates can be suppressed by high/low current operation, elevated temperature, and pH adjustment. (4) UV-radiation showed promise in assisting electrolytic TOC removal in beaker tests, but was not substantiated in limited single cell testing. This may have been due to non-optimum configurations of the single cell test rig and the light source.

  6. Radiation effects in semiconductors

    CERN Document Server

    2011-01-01

    There is a need to understand and combat potential radiation damage problems in semiconductor devices and circuits. Written by international experts, this book explains the effects of radiation on semiconductor devices, radiation detectors, and electronic devices and components. These contributors explore emerging applications, detector technologies, circuit design techniques, new materials, and innovative system approaches. The text focuses on how the technology is being used rather than the mathematical foundations behind it. It covers CMOS radiation-tolerant circuit implementations, CMOS pr

  7. Market survey of semiconductors

    International Nuclear Information System (INIS)

    Mackintosh, I.M.; Diegel, D.; Brown, A.; Brinker, C.S. den

    1977-06-01

    Examination of technology and product trends over the range of current and future products in integrated circuits and optoelectronic displays. Analysis and forecast of major economic influences that affect the production costs of integrated circuits and optoelectronic displays. Forecast of the applications and markets for integrated circuits up to 1985 in West Europe, the USA and Japan. Historic development of the semiconductor industry and the prevailing tendencies - factors which influence success in the semiconductor industry. (orig.) [de

  8. Electronic properties of semiconductor heterostructures

    International Nuclear Information System (INIS)

    Einevoll, G.T.

    1991-02-01

    Ten papers on the electronic properties of semiconductors and semiconductor heterostructures constitute the backbone of this thesis. Four papers address the form and validity of the single-band effective mass approximation for semiconductor heterostructures. In four other papers properties of acceptor states in bulk semiconductors and semiconductor heterostructures are studied using the novel effective bond-orbital model. The last two papers deal with localized excitions. 122 refs

  9. Producer responsibility and recycling solar photovoltaic modules

    International Nuclear Information System (INIS)

    McDonald, N.C.; Pearce, J.M.

    2010-01-01

    Rapid expansion of the solar photovoltaic (PV) industry is quickly causing solar to play a growing importance in the energy mix of the world. Over the full life cycle, although to a smaller degree than traditional energy sources, PV also creates solid waste. This paper examines the potential need for PV recycling policies by analyzing existing recycling protocols for the five major types of commercialized PV materials. The amount of recoverable semiconductor material and glass in a 1 m 2 area solar module for the five types of cells is quantified both physically and the profit potential of recycling is determined. The cost of landfill disposal of the whole solar module, including the glass and semiconductor was also determined for each type of solar module. It was found that the economic motivation to recycle most PV modules is unfavorable without appropriate policies. Results are discussed on the need to regulate for appropriate energy and environmental policy in the PV manufacturing industry particularly for PV containing hazardous materials. The results demonstrate the need to encourage producer responsibility not only in the PV manufacturing sector but also in the entire energy industry.

  10. Pore-filled electrolyte membranes for facile fabrication of long-term stable dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Seo, Seok-Jun; Cha, Hyeon-Jung; Kang, Yong Soo; Kang, Moon-Sung

    2015-01-01

    Graphical abstract: Display Omitted -- Highlights: •Pore-filled film electrolytes (PFEMs) were investigated for facile DSSC fabrication. •Optimal mixed solvent was suggested to enhance the long-term stability of DSSCs. •The PFEMs promised both the excellent thermal stability and energy efficiency. •Thephotovoltaic efficiency was well correlated with porous structure of substrates. -- ABSTRACT: Pore-filled electrolyte membranes (PFEMs) have been prepared by employing an optimized porous substrate and stable electrolyte composition for a facile manufacturing process of dye-sensitized solar cells (DSSCs). The PFEMs could be easily loaded into a photovoltaic device without adding a traditional electrolyte injection through a hole. In order to meet the requirements of both high energy conversion efficiency and proper long-term stability, three different solvents with high boiling point, i.e. valeronitrile, dimethyl sulfoxide, and dimethylacetamide, were appropriately mixed as a volumetric ratio of 7:2:1, respectively. As a result, similar conductivity and viscosity as well as better chemical stability were obtained compared to those of conventional 3-methoxypropionitrile-based electrolyte. In addition, linear relations were observed between the photovoltaic efficiency and porous film properties (i.e. porosity and tortuosity). The DSSC employing the PFEM doped with the mixed solvent based electrolyte exhibited the photon-to-current conversion efficiency of 6.30% at one sun condition. Moreover, the long-term stability test fixed at an elevated temperature of 85 °C exhibited outstanding durability of DSSC for 500 h

  11. Current challenges in organic photovoltaic solar energy conversion.

    Science.gov (United States)

    Schlenker, Cody W; Thompson, Mark E

    2012-01-01

    Over the last 10 years, significant interest in utilizing conjugated organic molecules for solid-state solar to electric conversion has produced rapid improvement in device efficiencies. Organic photovoltaic (OPV) devices are attractive for their compatibility with low-cost processing techniques and thin-film applicability to flexible and conformal applications. However, many of the processes that lead to power losses in these systems still remain poorly understood, posing a significant challenge for the future efficiency improvements required to make these devices an attractive solar technology. While semiconductor band models have been employed to describe OPV operation, a more appropriate molecular picture of the pertinent processes is beginning to emerge. This chapter presents mechanisms of OPV device operation, based on the bound molecular nature of the involved transient species. With the intention to underscore the importance of considering both thermodynamic and kinetic factors, recent progress in elucidating molecular characteristics that dictate photovoltage losses in heterojunction organic photovoltaics is also discussed.

  12. 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.

  13. Dextran based highly conductive hydrogel polysulfide electrolyte for efficient quasi-solid-state quantum dot-sensitized solar cells

    International Nuclear Information System (INIS)

    Chen, Hong-Yan; Lin, Ling; Yu, Xiao-Yun; Qiu, Kang-Qiang; Lü, Xian-Yong; Kuang, Dai-Bin; Su, Cheng-Yong

    2013-01-01

    electrolyte based quasi-solid-state QDSSC under 0.12 sun illumination. The high conductivity and the good permeation of gel electrolyte may contribute mainly to its excellent photovoltaic performance

  14. Effect of COOH-functionalized SWCNT addition on the electrical and photovoltaic characteristics of Malachite Green dye based photovoltaic cells

    International Nuclear Information System (INIS)

    Chakraborty, S.; Manik, N. B.

    2014-01-01

    We report the effect of COOH-functionalized single walled carbon nanotubes (COOH-SWCNT) on the electrical and photovoltaic characteristics of Malachite Green (MG) dye based photovoltaic cells. Two different types of photovoltaic cells were prepared, one with MG dye and another by incorporating COOH-SWCNT with this dye. Cells were characterized through different electrical and photovoltaic measurements including photocurrent measurements with pulsed radiation. From the dark current—voltage (I–V) characteristic results, we observed a certain transition voltage (V th ) for both the cells beyond which the conduction mechanism of the cells change sharply. For the MG dye, V th is 3.9 V whereas for COOH-SWCNT mixed with this dye, V th drops to 2.7 V. The device performance improves due to the incorporation of COOH-SWCNT. The open circuit voltage and short circuit current density change from 4.2 to 97 mV and from 108 to 965 μA/cm 2 respectively. Observations from photocurrent measurements show that the rate of growth and decay of the photocurrent are quite faster in the presence of COOH-SWCNT. This observation indicates a faster charge separation processes due to the incorporation of COOH-SWCNT in the MG dye cells. The high aspect ratio of COOH-SWCNT allows efficient conduction pathways for the generated charge carriers. (semiconductor devices)

  15. POLYMER ELECTROLYTE MEMBRANE FUEL CELLS

    DEFF Research Database (Denmark)

    2001-01-01

    A method for preparing polybenzimidazole or polybenzimidazole blend membranes and fabricating gas diffusion electrodes and membrane-electrode assemblies is provided for a high temperature polymer electrolyte membrane fuel cell. Blend polymer electrolyte membranes based on PBI and various...... thermoplastic polymers for high temperature polymer electrolyte fuel cells have also been developed. Miscible blends are used for solution casting of polymer membranes (solid electrolytes). High conductivity and enhanced mechanical strength were obtained for the blend polymer solid electrolytes....... With the thermally resistant polymer, e.g., polybenzimidazole or a mixture of polybenzimidazole and other thermoplastics as binder, the carbon-supported noble metal catalyst is tape-cast onto a hydrophobic supporting substrate. When doped with an acid mixture, electrodes are assembled with an acid doped solid...

  16. Photophysics and electrochemistry relevant to photocatalytic water splitting involved at solid–electrolyte interfaces

    KAUST Repository

    Shinagawa, Tatsuya

    2016-08-04

    Direct photon to chemical energy conversion using semiconductor-electrocatalyst-electrolyte interfaces has been extensively investigated for more than a half century. Many studies have focused on screening materials for efficient photocatalysis. Photocatalytic efficiency has been improved during this period but is not sufficient for industrial commercialization. Detailed elucidation on the photocatalytic water splitting process leads to consecutive six reaction steps with the fundamental parameters involved: The photocatalysis is initiated involving photophysics derived from various semiconductor properties (1: photon absorption, 2: exciton separation). The generated charge carriers need to be transferred to surfaces effectively utilizing the interfaces (3: carrier diffusion, 4: carrier transport). Consequently, electrocatalysis finishes the process by producing products on the surface (5: catalytic efficiency, 6: mass transfer of reactants and products). Successful photocatalytic water splitting requires the enhancement of efficiency at each stage. Most critically, a fundamental understanding of the interfacial phenomena is highly desired for establishing "photocatalysis by design" concepts, where the kinetic bottleneck within a process is identified by further improving the specific properties of photocatalytic materials as opposed to blind material screening. Theoretical modeling using the identified quantitative parameters can effectively predict the theoretically attainable photon-conversion yields. This article provides an overview of the state-of-the-art theoretical understanding of interfacial problems mainly developed in our laboratory. Photocatalytic water splitting (especially hydrogen evolution on metal surfaces) was selected as a topic, and the photophysical and electrochemical processes that occur at semiconductor-metal, semiconductor-electrolyte and metal-electrolyte interfaces are discussed.

  17. BIPV-powered smart windows utilizing photovoltaic and electrochromic devices.

    Science.gov (United States)

    Ma, Rong-Hua; Chen, Yu-Chia

    2012-01-01

    A BIPV-powered smart window comprising a building-integrated photovoltaic (BIPV) panel and an all-solid-state electrochromic (EC) stack is proposed. In the proposed device, the output voltage of the BIPV panel varies in accordance with the intensity of the incident light and is modulated in such a way as to generate the EC stack voltage required to maintain the indoor illuminance within a specified range. Two different EC stacks are fabricated and characterized, namely one stack comprising ITO/WO(3)/Ta(2)O(5)/ITO and one stack comprising ITO/WO(3)/lithium-polymer electrolyte/ITO. It is shown that of the two stacks, the ITO/WO(3)/lithium-polymer electrolyte/ITO stack has a larger absorptance (i.e., approximately 99% at a driving voltage of 3.5 V). The experimental results show that the smart window incorporating an ITO/WO(3)/lithium-polymer electrolyte/ITO stack with an electrolyte thickness of 1.0 μm provides an indoor illuminance range of 750-1,500 Lux under typical summertime conditions in Taiwan.

  18. BIPV-Powered Smart Windows Utilizing Photovoltaic and Electrochromic Devices

    Directory of Open Access Journals (Sweden)

    Yu-Chia Chen

    2011-12-01

    Full Text Available A BIPV-powered smart window comprising a building-integrated photovoltaic (BIPV panel and an all-solid-state electrochromic (EC stack is proposed. In the proposed device, the output voltage of the BIPV panel varies in accordance with the intensity of the incident light and is modulated in such a way as to generate the EC stack voltage required to maintain the indoor illuminance within a specified range. Two different EC stacks are fabricated and characterized, namely one stack comprising ITO/WO3/Ta2O5/ITO and one stack comprising ITO/WO3/lithium-polymer electrolyte/ITO. It is shown that of the two stacks, the ITO/WO3/lithium-polymer electrolyte/ITO stack has a larger absorptance (i.e., approximately 99% at a driving voltage of 3.5 V. The experimental results show that the smart window incorporating an ITO/WO3/lithium-polymer electrolyte/ITO stack with an electrolyte thickness of 1.0 μm provides an indoor illuminance range of 750–1,500 Lux under typical summertime conditions in Taiwan.

  19. Photovoltaic module and interlocked stack of photovoltaic modules

    Science.gov (United States)

    Wares, Brian S.

    2012-09-04

    One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame having at least a top member and a bottom member. A plurality of alignment features are included on the top member of each frame, and a plurality of alignment features are included on the bottom member of each frame. Adjacent photovoltaic modules are interlocked by the alignment features on the top member of a lower module fitting together with the alignment features on the bottom member of an upper module. Other embodiments, features and aspects are also disclosed.

  20. Three-phase Photovoltaic Systems

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Sera, Dezso; Máthé, Lászlo

    2015-01-01

    , detailing the different photovoltaic inverter structures and topologies as well as discussing the different control layers within a grid-connected photovoltaic plant. Modulation schemes for various photovoltaic inverter topologies, grid synchronization, current control, active and reactive power control......Photovoltaic technology has experienced unprecedented growth in the last two decades, transforming from mainly off-grid niche generation to a major renewable energy technology, reaching approximately 180 GW of capacity worldwide at the end of 2014. Large photovoltaic power plants interfacing...... the grid through a three-phase power electronic converter are now well on the way to becoming a major player in the power system in many countries. Therefore, this article gives an overview of photovoltaic systems with a focus on three-phase applications, presenting these both from a hardware point of view...

  1. 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.

  2. 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.

  3. 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

  4. ZnO-based nanocrystalline powders with applications in hybrid photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Damonte, L.C. [Dto. De Fisica, UNLP, IFLP-CCT-CONICET, C.C.67 (1900) La Plata (Argentina); Dto. De Fisica Aplicada, Universidad Politecnica de Valencia, Cami de Vera s/n (46071) Valencia (Spain); Donderis, V. [Dto. De Ingenieria Electrica, Universidad Politecnica de Valencia, Cami de Vera s/n (46071) Valencia (Spain); Ferrari, S.; Meyer, M. [Dto. De Fisica, UNLP, IFLP-CCT-CONICET, C.C.67 (1900) La Plata (Argentina); Orozco, J. [Dto. de Ingenieria Mecanica y Materiales, Universidad Politecnica de Valencia, Cami de Vera s/n (46071) Valencia (Spain); Hernandez-Fenollosa, M.A. [Dto. De Fisica Aplicada, Universidad Politecnica de Valencia, Cami de Vera s/n (46071) Valencia (Spain)

    2010-06-15

    In recent years there has been a growing interest in the development of hybrid photovoltaic cells consisting of new materials, such as devices based on the combination of a wide gap semiconductor and an organic dye (dye-sensitized solar cells, DSSC). In this paper we obtain nano-zinc oxide particles whose optical and electrical properties have been modified by the presence of small amounts of Al or In acting as dopants. The aim of this study is to improve the compatibility of each of the compounds present in the photovoltaic solar cell. The knowledge gained will provide input to guide the processes in the manufacture of hybrid solar cells. (author)

  5. Photovoltaics: The present presages the future

    International Nuclear Information System (INIS)

    Thornton, J.; Brown, L.

    1992-01-01

    This article is a technical assessment on photovoltaics and what effect new technology has on the ability of photovoltaics to compete in the utility market. The topics of the article include the solar resource, photovoltaic cells and systems, thick and thin film cells, the spherical cell, photovoltaic modules and systems, photovoltaic economics and utility applications, and technology transfer programs in the area of photovoltaic manufacturing

  6. Electron states at electrolyte/n-GaN and electrolyte/n-InGaN interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Rudinsky, M. E., E-mail: rudinskym@mail.ru; Gutkin, A. A.; Brunkov, P. N. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2012-06-15

    The differential capacitance and differential active conductance of rectifying contacts of n-GaN and n-In{sub x}Ga{sub 1-x}N (x Almost-Equal-To 0.15) with an electrolyte (0.2 M aqueous solutions of NaOH, NaCl, or HCl) have been studied. It was found that electron states with energies corresponding to the upper half of the energy gap of a semiconductor exist at the interface between these semiconductors and a NaOH solution. The density and characteristic recharging time of states noticeably contributing to the differential capacitance and differential active conductance at probe-voltage frequencies of 0.3-1 kHz grow with their binding energy and, for states lying at 0.15-0.3 eV below the conduction-band bottom of n-GaN, fall within the ranges 10{sup 12}-2 Multiplication-Sign 10{sup 13} cm{sup -2} eV{sup -1} and 10{sup -4}-10{sup -2} s, respectively. For contacts with NaCl and HCl solutions, there are no states of this kind. It is assumed that the observed states are related to the adsorption of hydroxyl groups.

  7. Photovoltaic facilities, legal guidebook

    International Nuclear Information System (INIS)

    Maincent, G.

    2011-01-01

    Important debates about the photovoltaic industry took place in 2009 and 2010 which have led to some evolutions of the French law having an economical impact on the arrangement of photovoltaic projects. The aim of this supplement to 'Droit de l'Environnement' journal is to answer some important questions at a time when the electricity market is not fully structured: the setting up of solar cell panels, town planing and property constraints; connection to the grid; project financing: power generation tariffs, partnership contract; the new legal framework set up in 2011: moratorium and new legal scheme; is 'green fiscality' still green and attractive? Settlement of disputes with the French government; actors reactions: authorities and professionals, opinion of an expert. (J.S.)

  8. Photovoltaic solar energy conversion

    CERN Document Server

    Bauer, Gottfried H

    2015-01-01

    This concise primer on photovoltaic solar energy conversion invites readers to reflect on the conversion of solar light into energy at the most fundamental level and encourages newcomers to the field to help find meaningful answers on how photovoltaic solar energy conversion can work (better), eventually contributing to its ongoing advancement. The book is based on lectures given to graduate students in the Physics Department at the University of Oldenburg over the last two decades, yet also provides an easy-to-follow introduction for doctoral and postdoctoral students from related disciplines such as the materials sciences and electrical engineering. Inspired by classic textbooks in the field, it reflects the author’s own ideas on how to understand, visualize and eventually teach the microscopic physical mechanisms and effects, while keeping the text as concise as possible so as to introduce interested readers to the field and balancing essential knowledge with open questions.

  9. Photovoltaic prospects in Europe

    Science.gov (United States)

    Starr, M. R.

    The economics of solar cells is reviewed with an eye to potential cost reductions in processing, and potential markets are explored. Current solar cell systems costs are noted to be on the road to achieving the U.S. DoE goals of $0.40/kWp by 1990. Continued progress will depend on technical developments in cheaper materials and processes, scaling up production, and the success of sales programs. Various consumer and professional markets are outlined, with a prediction that a 12 MWp deman will be reached as a steady state by 1995. Photovoltaic panels may conceivably replace conventional roofing materials, resulting in the projection that, if grid-supplied power continues to inflate in price, then all new European homes would be equipped with photovoltaics by the year 2000. Further, accomplishment of the cost goals could generate a 1 GWp/yr industrial market at the same time.

  10. Temperature compensated photovoltaic array

    Science.gov (United States)

    Mosher, Dan Michael

    1997-11-18

    A temperature compensated photovoltaic module (20) comprised of a series of solar cells (22) having a thermally activated switch (24) connected in parallel with several of the cells (22). The photovoltaic module (20) is adapted to charge conventional batteries having a temperature coefficient (TC) differing from the temperature coefficient (TC) of the module (20). The calibration temperatures of the switches (24) are chosen whereby the colder the ambient temperature for the module (20), the more switches that are on and form a closed circuit to short the associated solar cells (22). By shorting some of the solar cells (22) as the ambient temperature decreases, the battery being charged by the module (20) is not excessively overcharged at lower temperatures. PV module (20) is an integrated solution that is reliable and inexpensive.

  11. Photovoltaic Solar Energy Generation

    CERN Document Server

    Lotsch, H.K.V; U.Hoffmann, Volker; Rhodes, William T; Asakura, Toshimitsu; Brenner, Karl-Heinz; Hänsch, Theodor W; Kamiya, Takeshi; Krausz, Ferenc; Monemar, Bo; Venghaus, Herbert; Weber, Horst; Weinfurter, Harald

    2005-01-01

    This comprehensive description and discussion of photovoltaics (PV) is presented at a level that makes it accessible to the interested academic. Starting with an historical overview, the text outlines the relevance of photovoltaics today and in the future. Then follows an introduction to the physical background of solar cells and the most important materials and technologies, with particular emphasis placed on future developments and prospects. The book goes beyond technology by also describing the path from the cell to the module to the system, proceeding to important applications, such as grid-connected and stand-alone systems. The composition and development of the markets and the role of PV in future energy systems are also considered. Finally, the discussion turns to the future structure of energy supplies, expected to comprise more distributed generation, and addresses synergies and competition from other carbon-free energy sources.

  12. Photovoltaic solar energy

    International Nuclear Information System (INIS)

    Mouratoglou, P.; Therond, P.G.

    2009-01-01

    The most important assets of photovoltaic energy for sustainable development are its simplicity (no need for complicated thermodynamical cycles) and the universal availability of the sun which explains its great popularity. The main restraint to its full development is the high cost of the technologies used. The silicon technology is the historical technology, it has high conversion rates but is expensive because of high fabrication costs. This technology represents 80% of the market. On the other hand the thin film technology with CdTe, CIS or CIGS is promising in terms of costs but requires research works to increase its conversion rate. Japan and Germany are the leader countries in terms of photovoltaic for research, industrial fabrication or state support, they are followed by Spain, Usa, and China. (A.C.)

  13. Photovoltaic systems. Program summary

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-12-01

    Each of the Department of Energy's Photovoltaic Systems Program projects funded and/or in existence during fiscal year 1978 (October 1, 1977 through September 30, 1978) are described. The project sheets list the contractor, principal investigator, and contract number and funding and summarize the programs and status. The program is divided into various elements: program assessment and integration, research and advanced development, technology development, system definition and development, system application experiments, and standards and performance criteria. (WHK)

  14. Photovoltaic energy cost limit

    International Nuclear Information System (INIS)

    Coiante, D.

    1992-01-01

    Referring to a photovoltaic system for grid connected applications, a parametric expression of kWh cost is derived. The limit of kWh cost is carried out extrapolating the values of cost components to their lowest figure. The reliability of the forecast is checked by disaggregating kWh cost in direct and indirect costs and by discussing the possible cost reduction of each component

  15. Experimental integrated photovoltaic systems

    International Nuclear Information System (INIS)

    Pop-Jordanov, Jordan; Markovska, Natasha; Dimitrov, D.; Kocev, K.; Dimitrovski, D.

    2000-01-01

    Recently, the interest in building-integrated photovoltaic installations has started to increase within governmental and municipality authorities, as well as some industrial companies. To serve a national public-awareness program of solar electricity promotion and education, the indigenous solar energy potential, optimization of possible PV installation, and three test cases of building-integrated grid-connected experimental facilities have been studied. The results showed the feasibility and performance of the proposed concepts. (Original)

  16. Portable photovoltaic irrigation pumps

    Energy Technology Data Exchange (ETDEWEB)

    Furber, J. D.

    1980-07-01

    Experiences in developing a solar-powered irrigation pump to meet the needs of poor farmers in developing nations are summarized. The design which evolved is small and portable, employing a high-efficiency electric pump, powered by photovoltaic panels. Particular emphasis is placed on how the system works, and on early field problems experienced with the first prototypes. The resolution of these problems and the performance of actual systems in various countries is presented and user responses are noted.

  17. Photovoltaic cell array

    Science.gov (United States)

    Eliason, J. T. (Inventor)

    1976-01-01

    A photovoltaic cell array consisting of parallel columns of silicon filaments is described. Each fiber is doped to produce an inner region of one polarity type and an outer region of an opposite polarity type to thereby form a continuous radial semi conductor junction. Spaced rows of electrical contacts alternately connect to the inner and outer regions to provide a plurality of electrical outputs which may be combined in parallel or in series.

  18. Increased voltage photovoltaic cell

    Science.gov (United States)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  19. Photovoltaic sources modeling

    CERN Document Server

    Petrone, Giovanni; Spagnuolo, Giovanni

    2016-01-01

    This comprehensive guide surveys all available models for simulating a photovoltaic (PV) generator at different levels of granularity, from cell to system level, in uniform as well as in mismatched conditions. Providing a thorough comparison among the models, engineers have all the elements needed to choose the right PV array model for specific applications or environmental conditions matched with the model of the electronic circuit used to maximize the PV power production.

  20. Photovoltaic energy systems. Program summary

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-01-01

    The ongoing research, development, and demonstration efforts of the Photovoltaics Program are highlighted and each of the US Department of Energy's current photovoltaics projects initiated or renewed during fiscal year 1981 is described, including its title, directing organization, project engineer, contractor, principal investigator, contract period, funding, and objectives. The Photovoltaics Program is briefly summarized, including the history and organization and highlights of the research and development and of planning, assessment, and integration. Also summarized is the Federal Photovoltaic Utilization Program. An exhaustive bibliography is included. (LEW)

  1. Solar photovoltaics for development applications

    Energy Technology Data Exchange (ETDEWEB)

    Shepperd, L.W. [Florida Solar Energy Center, Cape Canaveral, FL (United States); Richards, E.H. [Sandia National Labs., Albuquerque, NM (United States)

    1993-08-01

    This document introduces photovoltaic technology to individuals and groups specializing in development activities. Examples of actual installations illustrate the many services supplied by photovoltaic systems in development applications, including water pumping, lighting, health care, refrigeration, communications, and a variety of productive uses. The various aspects of the technology are explored to help potential users evaluate whether photovoltaics can assist them in achieving their organizational goals. Basic system design, financing techniques, and the importance of infrastructure are included, along with additional sources of information and major US photovoltaic system suppliers.

  2. Modeling Photovoltaic Power

    Directory of Open Access Journals (Sweden)

    F. Mavromatakis

    2016-10-01

    Full Text Available A robust and reliable model describing the power produced by a photovoltaic system is needed in order to be able to detect module failures, inverter malfunction, shadowing effects and other factors that may result to energy losses. In addition, a reliable model enables an investor to perform accurate estimates of the system energy production, payback times etc. The model utilizes the global irradiance reaching the plane of the photovoltaic modules since in almost all Photovoltaic (PV facilities the beam and the diffuse solar irradiances are not recorded. The airmass, the angle of incidence and the efficiency drop due to low values of solar irradiance are taken into account. Currently, the model is validated through the use of high quality data available from the National Renewable Energy Laboratory (USA. The data were acquired with IV tracers while the meteorological conditions were also recorded. Several modules of different technologies were deployed but here we present results from a single crystalline module. The performance of the model is acceptable at a level of 5% despite the assumptions made. The dependence of the residuals upon solar irradiance temperature, airmass and angle of incidence is also explored and future work is described.

  3. Photocurrent of Photovoltaic Cells

    Science.gov (United States)

    Peeler, Seth; McIntyre, Max; Cossel, Raquel; Bowser, Chris; Tzolov, Marian

    Photovoltaic cells can be used to harness clean, renewable energy from light. Examined in this project were photovoltaic cells based on a bulk heterojunction between PCPDTBT and PCBM sandwiched between an ITO anode and an Al cathode. Current-voltage characteristics and impedance spectra for multiple photovoltaic devices were taken under varying DC electrical bias and different level of illumination. This data was interpreted in terms of an equivalent circuit with linear elements, e.g. capacitance, series resistance, and parallel resistance. A physical interpretation of each circuit element will be presented. The spectral response of the devices was characterized by optical transmission and photocurrent spectroscopy using a spectrometer in the spectral range from 300 to 900 nm. The DC measurements confirmed that the devices are electrically rectifying. The AC measurements allowed modeling of the devices as a dielectric between two electrodes with injection current passing through it. The characteristic peaks for both PCBDTBT and PCBM are clearly visible in both the photocurrent and transmission data. The good correlation between the photocurrent and transmission data indicates photocurrent generation due to absorption in both materials constituting the heterojunction.

  4. Photovoltaics in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Bolcso, S L

    1983-06-01

    A literature review was carried out for the purpose of summarizing the current conditions existing and affecting photovoltaics (PV) technology in a Canadian context. Information is presented concerning: PV device materials and efficiencies; PV cell manufacturing techniques; other materials/device designs; photovoltaic costs, markets, and research and development; PV and microelectronics; and Canadian strengths and opportunities. It was concluded that PV's simplicity, amenability to mass production and environmentally benign nature will likely assure it a faster and eventually greater market penetration than any other renewable energy form (and possibly some conventional forms). It is recommended that the Ministry of State, Science and Technology coordinate a joint microelectronics-photovoltaic research effort, by: indentifying areas where joint efforts would be mutually beneficial; identifying the strategic value of PV; identifying a set of goals for Canadian programs; coordinating efforts between government, universities and industry; developing supporting strategies for the mining and smelting of indigenous semiconducting materials; determining the economic support required to develop a silicon processing plant for the production of microelectronic chips and PV cells; developing Canadian expertise in providing complete PV systems competitive in world markets; and developing a marketing strategy for a coordinated PV/microelectronics effort. 60 refs., 17 figs., 12 tabs.

  5. Precise, Self-Limited Epitaxy of Ultrathin Organic Semiconductors and Heterojunctions Tailored by van der Waals Interactions.

    Science.gov (United States)

    Wu, Bing; Zhao, Yinghe; Nan, Haiyan; Yang, Ziyi; Zhang, Yuhan; Zhao, Huijuan; He, Daowei; Jiang, Zonglin; Liu, Xiaolong; Li, Yun; Shi, Yi; Ni, Zhenhua; Wang, Jinlan; Xu, Jian-Bin; Wang, Xinran

    2016-06-08

    Precise assembly of semiconductor heterojunctions is the key to realize many optoelectronic devices. By exploiting the strong and tunable van der Waals (vdW) forces between graphene and organic small molecules, we demonstrate layer-by-layer epitaxy of ultrathin organic semiconductors and heterostructures with unprecedented precision with well-defined number of layers and self-limited characteristics. We further demonstrate organic p-n heterojunctions with molecularly flat interface, which exhibit excellent rectifying behavior and photovoltaic responses. The self-limited organic molecular beam epitaxy (SLOMBE) is generically applicable for many layered small-molecule semiconductors and may lead to advanced organic optoelectronic devices beyond bulk heterojunctions.

  6. A highly efficient electric additive for enhancing photovoltaic performance of dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    N-cetylpyridinium iodide (N-CPI) as a new electric additive for enhancing photovoltaic performance of the dye-sensitized solar cell (DSSC) was studied.It showed high efficiency for enhancing both the open-circuit voltage and the short-circuit current density of DSSC when the suitable amount of N-CPI as 0.02 M was added in liquid electrolyte.The energy conversion effi- ciency of DSSC increased from 4.429% to 6.535%,with 47.55% enhancement.Therefore,it is a highly efficient electric addi- tive for DSSC.The intrinsic reason is owing to the special molecular structure of N-CPI,which contains two different polarity groups.As a surfactant,N-CPI could form ordered arrangement in liquid electrolyte,which affects the diffusing ability and the redox reaction of I-/I3-,and further affects the photovoltaic performance of DSSC.

  7. Fundamentals of semiconductor lasers

    CERN Document Server

    Numai, Takahiro

    2015-01-01

    This book explains physics under the operating principles of semiconductor lasers in detail based on the experience of the author, dealing with the first manufacturing of phase-shifted DFB-LDs and recent research on transverse modes.   The book also bridges a wide gap between journal papers and textbooks, requiring only an undergraduate-level knowledge of electromagnetism and quantum mechanics, and helps readers to understand journal papers where definitions of some technical terms vary, depending on the paper. Two definitions of the photon density in the rate equations and two definitions of the phase-shift in the phase-shifted DFB-LD are explained, and differences in the calculated results are indicated, depending on the definitions.    Readers can understand the physics of semiconductor lasers and analytical tools for Fabry-Perot LDs, DFB-LDs, and VCSELs and will be stimulated to develop semiconductor lasers themselves.

  8. Coherent dynamics in semiconductors

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher

    1998-01-01

    enhanced in quantum confined lower-dimensional systems, where exciton and biexciton effects dominate the spectra even at room temperature. The coherent dynamics of excitons are at modest densities well described by the optical Bloch equations and a number of the dynamical effects known from atomic......Ultrafast nonlinear optical spectroscopy is used to study the coherent dynamics of optically excited electron-hole pairs in semiconductors. Coulomb interaction implies that the optical inter-band transitions are dominated, at least at low temperatures, by excitonic effects. They are further...... and molecular systems are found and studied in the exciton-biexciton system of semiconductors. At densities where strong exciton interactions, or many-body effects, become dominant, the semiconductor Bloch equations present a more rigorous treatment of the phenomena Ultrafast degenerate four-wave mixing is used...

  9. Hydrogen in semiconductors II

    CERN Document Server

    Nickel, Norbert H; Weber, Eicke R; Nickel, Norbert H

    1999-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise that this tradition ...

  10. Electrolytic preconcentration in instrumental analysis.

    Science.gov (United States)

    Sioda, R E; Batley, G E; Lund, W; Wang, J; Leach, S C

    1986-05-01

    The use of electrolytic deposition as a separation and preconcentration step in trace metal analysis is reviewed. Both the principles and applications of the technique are dealt with in some detail. Electrolytic preconcentration can be combined with a variety of instrumental techniques. Special attention is given to stripping voltammetry, potentiometric stripping analysis, different combinations with atomic-absorption spectrometry, and the use of flow-through porous electrodes. It is pointed out that the electrolytic preconcentration technique deserves more extensive use as well as fundamental investigation.

  11. The photovoltaic pathway

    International Nuclear Information System (INIS)

    Jourde, P.; Guerin de Montgareuil, A.; Mattera, F.; Jaussaud, C.; Boulanger, P.; Veriat, G.; Firon, M.

    2004-01-01

    Photovoltaic conversion, the direct transformation of light into electricity, is, of the three pathways for solar energy, the one experiencing most rapid growth, and for which scientific and technological advances are most promising, as regards significant improvements in its economic balance. While the long-term trend, in Europe, is favorable, with annual growth set at 30%, the cost per photovoltaic kilowatt-hour remains some ten times higher than that achieved with natural gas or nuclear energy (after connection to the grid), this being a handicap, at first blush, for high power ratings. For remote locations, where its advantage is unquestionable, in spite of the added cost of storage between insolation periods (this more than compensating for savings in terms of connection costs), this pathway sets its future prospects on marked module cost reductions. Such reduction may only be achieved by way of technological breakthroughs, to which CEA, active as it has been, in this area, for some thirty years, intends making a contribution, as linchpin of French research and technology, and a key protagonist on the European scene. One of the avenues being pursued concerns fabrication of high-efficiency cells from mineral or organic thin films, with particularly strong expectations with respect to the all-polymer path, complementary of the silicon pathway. Concurrently, device reliability needs must be improved, this being another factor making for an improved overall balance. To achieve easier transfer to industry of laboratory outcomes, CEA is relying, in particular, on the new cell fabrication platform set up in Grenoble, this complementing its other R and D resources, including those installed at Cadarache, allowing testing of cells and entire photovoltaic systems in actual operating conditions. Another path for cost reductions being explored by CEA research workers consists in construction of systems integrated into the built environment: this affords new prospects

  12. MATLAB Simulation of Photovoltaic and Photovoltaic/Thermal Systems Performance

    Science.gov (United States)

    Nasir, Farah H. M.; Husaini, Yusnira

    2018-03-01

    The efficiency of the photovoltaic reduces when the photovoltaic cell temperature increased due to solar irradiance. One solution is come up with the cooling system photovoltaic system. This combination is forming the photovoltaic-thermal (PV/T) system. Not only will it generate electricity also heat at the same time. The aim of this research is to focus on the modeling and simulation of photovoltaic (PV) and photovoltaic-thermal (PV/T) electrical performance by using single-diode equivalent circuit model. Both PV and PV/T models are developed in Matlab/Simulink. By providing the cooling system in PV/T, the efficiency of the system can be increased by decreasing the PV cell temperature. The maximum thermal, electrical and total efficiency values of PV/T in the present research are 35.18%, 15.56% and 50.74% at solar irradiance of 400 W/m2, mass flow rate of 0.05kgs-1 and inlet temperature of 25 °C respectively has been obtained. The photovoltaic-thermal shows that the higher efficiency performance compared to the photovoltaic system.

  13. Advances in semiconductor lasers

    CERN Document Server

    Coleman, James J; Jagadish, Chennupati

    2012-01-01

    Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. Originally widely known as the ""Willardson and Beer"" Series, it has succeeded in publishing numerous landmark volumes and chapters. The series publishes timely, highly relevant volumes intended for long-term impact and reflecting the truly interdisciplinary nature of the field. The volumes in Semiconductors and Semimetals have been and will continue to be of great interest to physicists, chemists, materials scientists, and device engineers in academia, scien

  14. Superconductivity in doped semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Bustarret, E., E-mail: Etienne.bustarret@neel.cnrs.fr

    2015-07-15

    A historical survey of the main normal and superconducting state properties of several semiconductors doped into superconductivity is proposed. This class of materials includes selenides, tellurides, oxides and column-IV semiconductors. Most of the experimental data point to a weak coupling pairing mechanism, probably phonon-mediated in the case of diamond, but probably not in the case of strontium titanate, these being the most intensively studied materials over the last decade. Despite promising theoretical predictions based on a conventional mechanism, the occurrence of critical temperatures significantly higher than 10 K has not been yet verified. However, the class provides an enticing playground for testing theories and devices alike.

  15. Semiconductor opto-electronics

    CERN Document Server

    Moss, TS; Ellis, B

    1972-01-01

    Semiconductor Opto-Electronics focuses on opto-electronics, covering the basic physical phenomena and device behavior that arise from the interaction between electromagnetic radiation and electrons in a solid. The first nine chapters of this book are devoted to theoretical topics, discussing the interaction of electromagnetic waves with solids, dispersion theory and absorption processes, magneto-optical effects, and non-linear phenomena. Theories of photo-effects and photo-detectors are treated in detail, including the theories of radiation generation and the behavior of semiconductor lasers a

  16. Ternary chalcopyrite semiconductors

    CERN Document Server

    Shay, J L; Pamplin, B R

    2013-01-01

    Ternary Chalcopyrite Semiconductors: Growth, Electronic Properties, and Applications covers the developments of work in the I-III-VI2 and II-IV-V2 ternary chalcopyrite compounds. This book is composed of eight chapters that focus on the crystal growth, characterization, and applications of these compounds to optical communications systems. After briefly dealing with the status of ternary chalcopyrite compounds, this book goes on describing the crystal growth of II-IV-V2 and I-III-VI2 single crystals. Chapters 3 and 4 examine the energy band structure of these semiconductor compounds, illustrat

  17. Compound semiconductor device physics

    CERN Document Server

    Tiwari, Sandip

    2013-01-01

    This book provides one of the most rigorous treatments of compound semiconductor device physics yet published. A complete understanding of modern devices requires a working knowledge of low-dimensional physics, the use of statistical methods, and the use of one-, two-, and three-dimensional analytical and numerical analysis techniques. With its systematic and detailed**discussion of these topics, this book is ideal for both the researcher and the student. Although the emphasis of this text is on compound semiconductor devices, many of the principles discussed will also be useful to those inter

  18. Introductory semiconductor device physics

    CERN Document Server

    Parker, Greg

    2004-01-01

    ATOMS AND BONDINGThe Periodic TableIonic BondingCovalent BondingMetallic bondingvan der Waals BondingStart a DatabaseENERGY BANDS AND EFFECTIVE MASSSemiconductors, Insulators and MetalsSemiconductorsInsulatorsMetalsThe Concept of Effective MassCARRIER CONCENTRATIONS IN SEMICONDUCTORSDonors and AcceptorsFermi-LevelCarrier Concentration EquationsDonors and Acceptors Both PresentCONDUCTION IN SEMICONDUCTORSCarrier DriftCarrier MobilitySaturated Drift VelocityMobility Variation with TemperatureA Derivation of Ohm's LawDrift Current EquationsSemiconductor Band Diagrams with an Electric Field Presen

  19. Photoelectrochemical processes in organic semiconductor: Ambipolar perylene diimide thin film

    Science.gov (United States)

    Kim, Jung Yong; Chung, In Jae

    2018-03-01

    A thin film of N,N‧-dioctadecyl-3,4,9,10-perylene tetracarboxylic diimide (PTCDI-C18) is spin-coated on indium tin oxide (ITO) glass. Using the PTCDI-C18/ITO electrode, we fabricate a photoelectrochemical cell with the ITO/PTCDI-C18/Redox Electrolyte/Pt configuration. The electrochemical properties of this device are investigated as a function of hydroquinone (HQ) concentration, bias voltage, and wavelength of light. Anodic photocurrent is observed at V ≥ -0.2 V vs. Ag/AgCl, indicating that the PTCDI-C18 film acts as an n-type semiconductor as usual. However, when benzoquinone (BQ) is inserted into the electrolyte system instead of HQ, cathodic photocurrent is observed at V ≤ 0.0 V, displaying that PTCDI-C18 abnormally serves as a p-type semiconductor. Hence the overall results reveal that the PTCDI-C18 film can be an ambipolar functional semiconductor depending on the redox couple in the appropriate voltage.

  20. Mechanism of plasmon-mediated enhancement of photovoltaic efficiency

    International Nuclear Information System (INIS)

    Jacak, W; Jacak, J; Donderowicz, W; Jacak, L; Krasnyj, J

    2011-01-01

    Metallic nanospheres (Au, Ag, Cu) deposited on a photovoltaic (PV)-active semiconductor surface can act as light converters, collecting energy of incident photons in plasmon oscillations. This energy can be next transferred to a semiconductor substrate via a near-field channel, in a more efficient manner in comparison with the direct photo-effect. We explain this enhancement by inclusion of indirect interband transitions in a semiconductor layer due to the near-field coupling with plasmon radiation in nanoscale of the metallic components, where the momentum is not conserved as the system is not translationally invariant. The model of the nanosphere plasmons is developed (random phase approximation, analytical version, adjusted to description of large metallic clusters, with a radius of 10-60 nm) including surface and volume modes. Damping of plasmons is analysed via Lorentz friction, and irradiation losses in the far- and near-field regimes. Resulting resonance shifts are verified experimentally for Au and Ag colloidal water solutions with respect to particle size. Probability of the electron interband transition (within the Fermi golden rule) in the substrate semiconductor induced by coupling to plasmons in the near-field regime turns out to be significantly larger than for coupling of electrons to planar-wave photons. This is of practical importance for enhancement of thin-film solar cell efficiency, both for semiconductor type (such as III-V semiconductor based cells) and for conjugate-polymer-based or dye organic plastic cells, intensively developed at present. We have described also a non-dissipative collective mode of surface plasmons in a chain of near-field-coupled metallic nanospheres, for particular size, separation parameters and wavelengths. This would find an application in sub-diffraction electro-photonic circuit arrangement and for possible energy transport in solar cells, in particular in organic materials with low mobility of carriers.

  1. SUNRAYCE 95: Working safely with lead-acid batteries and photovoltaic power systems

    Energy Technology Data Exchange (ETDEWEB)

    DePhillips, M.P.; Moskowitz, P.D.; Fthenakis, V.M. [Brookhaven National Lab., Upton, NY (United States). Biomedical and Environmental Assessment Group

    1994-05-27

    This document is a power system and battery safety handbook for participants in the SUNRAYCE 95 solar powered electric vehicle program. The topics of the handbook include batteries, photovoltaic modules, safety equipment needed for working with sulfuric acid electrolyte and batteries, battery transport, accident response, battery recharging and ventilation, electrical risks on-board vehicle, external electrical risks, electrical risk management strategies, and general maintenance including troubleshooting, hydrometer check and voltmeter check.

  2. Tunable radiation emitting semiconductor device

    NARCIS (Netherlands)

    2009-01-01

    A tunable radiation emitting semiconductor device includes at least one elongated structure at least partially fabricated from one or more semiconductor materials exhibiting a bandgap characteristic including one or more energy transitions whose energies correspond to photon energies of light

  3. Physical principles of semiconductor detectors

    International Nuclear Information System (INIS)

    Micek, S.L.

    1979-01-01

    The general properties of semiconductors with respect to the possibilities of their use as the ionization radiation detectors are discussed. Some chosen types of semiconductor junctions and their characteristics are briefly presented. There are also discussed the physical phenomena connected with the formation of barriers in various types of semiconductor counters. Finally, the basic properties of three main types of semiconductor detectors are given. (author)

  4. Metal semiconductor contacts and devices

    CERN Document Server

    Cohen, Simon S; Einspruch, Norman G

    1986-01-01

    VLSI Electronics Microstructure Science, Volume 13: Metal-Semiconductor Contacts and Devices presents the physics, technology, and applications of metal-semiconductor barriers in digital integrated circuits. The emphasis is placed on the interplay among the theory, processing, and characterization techniques in the development of practical metal-semiconductor contacts and devices.This volume contains chapters that are devoted to the discussion of the physics of metal-semiconductor interfaces and its basic phenomena; fabrication procedures; and interface characterization techniques, particularl

  5. Handbook of luminescent semiconductor materials

    CERN Document Server

    Bergman, Leah

    2011-01-01

    Photoluminescence spectroscopy is an important approach for examining the optical interactions in semiconductors and optical devices with the goal of gaining insight into material properties. With contributions from researchers at the forefront of this field, Handbook of Luminescent Semiconductor Materials explores the use of this technique to study semiconductor materials in a variety of applications, including solid-state lighting, solar energy conversion, optical devices, and biological imaging. After introducing basic semiconductor theory and photoluminescence principles, the book focuses

  6. The heat recovery with heat transfer methods from solar photovoltaic systems

    International Nuclear Information System (INIS)

    Özakın, A. N.; Karsli, S.; Kaya, F.; Güllüce, H.

    2016-01-01

    Although there are many fluctuations in energy prices, they seems like rising day by day. Thus energy recovery systems have increasingly trend. Photovoltaic systems converts solar radiation directly into electrical energy thanks to semiconductors. But due to the nature of semiconductors, whole of solar energy cannot turn into electrical energy and the remaining energy turns into waste heat. The aim of this research is evaluate this waste heat energy by air cooling system. So, the energy efficiency of the system will be increased using appropriate heat transfer technologies such as fin, turbulator etc. (paper)

  7. Solar photovoltaic applications seminar: design, installation and operation of small, stand-alone photovoltaic power systems

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-01

    This seminar material was developed primarily to provide solar photovoltaic (PV) applied engineering technology to the Federal community. An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. The seminar details general systems design and incorporates most known information from industry, academia, and Government concerning small solar cell power system design engineering, presented in a practical and applied manner. Solar PV power system applications involve classical direct electrical energy conversion and electric power system analysis and synthesis. Presentations and examples involve a variety of disciplines including structural analysis, electric power and load analysis, reliability, sizing and optimization; and, installation, operation and maintenance. Four specific system designs are demonstrated: water pumping, domestic uses, navigational and aircraft aids, and telecommunications. All of the applications discussed are for small power requirement (under 2 kilowatts), stand-alone systems to be used in remote locations. Also presented are practical lessons gained from currently installed and operating systems, problems at sites and their resolution, a logical progression through each major phase of system acquisition, as well as thorough design reviews for each application.

  8. Ionic liquids as electrolytes

    International Nuclear Information System (INIS)

    Galinski, Maciej; Lewandowski, Andrzej; Stepniak, Izabela

    2006-01-01

    Salts having a low melting point are liquid at room temperature, or even below, and form a new class of liquids usually called room temperature ionic liquids (RTIL). Information about RTILs can be found in the literature with such key words as: room temperature molten salt, low-temperature molten salt, ambient-temperature molten salt, liquid organic salt or simply ionic liquid. Their physicochemical properties are the same as high temperature ionic liquids, but the practical aspects of their maintenance or handling are different enough to merit a distinction. The class of ionic liquids, based on tetraalkylammonium cation and chloroaluminate anion, has been extensively studied since late 1970s of the XX century, following the works of Osteryoung. Systematic research on the application of chloroaluminate ionic liquids as solvents was performed in 1980s. However, ionic liquids based on aluminium halides are moisture sensitive. During the last decade an increasing number of new ionic liquids have been prepared and used as solvents. The general aim of this paper was to review the physical and chemical properties of RTILs from the point of view of their possible application as electrolytes in electrochemical processes and devices. The following points are discussed: melting and freezing, conductivity, viscosity, temperature dependence of conductivity, transport and transference numbers, electrochemical stability, possible application in aluminium electroplating, lithium batteries and in electrochemical capacitors

  9. Solid polymer electrolyte lithium batteries

    Science.gov (United States)

    Alamgir, Mohamed; Abraham, Kuzhikalail M.

    1993-01-01

    This invention pertains to Lithium batteries using Li ion (Li.sup.+) conductive solid polymer electrolytes composed of solvates of Li salts immobilized in a solid organic polymer matrix. In particular, this invention relates to Li batteries using solid polymer electrolytes derived by immobilizing solvates formed between a Li salt and an aprotic organic solvent (or mixture of such solvents) in poly(vinyl chloride).

  10. Electrolytes for lithium ion batteries

    Science.gov (United States)

    Vaughey, John; Jansen, Andrew N.; Dees, Dennis W.

    2014-08-05

    A family of electrolytes for use in a lithium ion battery. The genus of electrolytes includes ketone-based solvents, such as, 2,4-dimethyl-3-pentanone; 3,3-dimethyl 2-butanone(pinacolone) and 2-butanone. These solvents can be used in combination with non-Lewis Acid salts, such as Li.sub.2[B.sub.12F.sub.12] and LiBOB.

  11. Cosolvent electrolytes for electrochemical devices

    Science.gov (United States)

    Wessells, Colin Deane; Firouzi, Ali; Motallebi, Shahrokh; Strohband, Sven

    2018-01-23

    A method for stabilizing electrodes against dissolution and/or hydrolysis including use of cosolvents in liquid electrolyte batteries for three purposes: the extension of the calendar and cycle life time of electrodes that are partially soluble in liquid electrolytes, the purpose of limiting the rate of electrolysis of water into hydrogen and oxygen as a side reaction during battery operation, and for the purpose of cost reduction.

  12. Cosolvent electrolytes for electrochemical devices

    Science.gov (United States)

    Wessells, Colin Deane; Firouzi, Ali; Motallebi, Shahrokh; Strohband, Sven

    2018-02-13

    A system and method for stabilizing electrodes against dissolution and/or hydrolysis including use of cosolvents in liquid electrolyte batteries for three purposes: the extension of the calendar and cycle life time of electrodes that are partially soluble in liquid electrolytes, the purpose of limiting the rate of electrolysis of water into hydrogen and oxygen as a side reaction during battery operation, and for the purpose of cost reduction.

  13. High cation transport polymer electrolyte

    Science.gov (United States)

    Gerald, II, Rex E.; Rathke, Jerome W [Homer Glen, IL; Klingler, Robert J [Westmont, IL

    2007-06-05

    A solid state ion conducting electrolyte and a battery incorporating same. The electrolyte includes a polymer matrix with an alkali metal salt dissolved therein, the salt having an anion with a long or branched chain having not less than 5 carbon or silicon atoms therein. The polymer is preferably a polyether and the salt anion is preferably an alkyl or silyl moiety of from 5 to about 150 carbon/silicon atoms.

  14. Graphite-based photovoltaic cells

    Science.gov (United States)

    Lagally, Max; Liu, Feng

    2010-12-28

    The present invention uses lithographically patterned graphite stacks as the basic building elements of an efficient and economical photovoltaic cell. The basic design of the graphite-based photovoltaic cells includes a plurality of spatially separated graphite stacks, each comprising a plurality of vertically stacked, semiconducting graphene sheets (carbon nanoribbons) bridging electrically conductive contacts.

  15. Solar Photovoltaic Technology Basics | NREL

    Science.gov (United States)

    Photovoltaic Technology Basics Solar Photovoltaic Technology Basics Solar cells, also called found in sand) created an electric charge when exposed to sunlight. Soon solar cells were being used to power space satellites and smaller items like calculators and watches. Photo of a large silicon solar

  16. Photovoltaic conversion of laser energy

    Science.gov (United States)

    Stirn, R. J.

    1976-01-01

    The Schottky barrier photovoltaic converter is suggested as an alternative to the p/n junction photovoltaic devices for the conversion of laser energy to electrical energy. The structure, current, output, and voltage output of the Schottky device are summarized. The more advanced concepts of the multilayer Schottky barrier cell and the AMOS solar cell are briefly considered.

  17. Photovoltaic energy generation in Germany

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    An overview is given of the current state of the art regarding photovoltaic research and demonstration programmes in the Federal Republic of Germany. Also attention is paid to the companies and research institutes involved, and the long-term economical and technical prospects of photovoltaic energy. 13 figs., 4 tabs., 10 refs

  18. The photovoltaic ambitious of EDF

    International Nuclear Information System (INIS)

    Houot, G.

    2008-01-01

    Added to the wind energy, EDF develops the photovoltaic by its subsidiaries EDF Energies Nouvelles, for the big power plants and EDF Energies Nouvelles Reparties centralized on the market of small installations for roofs. The author analyzes the society management and project concerning the photovoltaic development. (A.L.B.)

  19. Depletion field focusing in semiconductors

    NARCIS (Netherlands)

    Prins, M.W.J.; Gelder, Van A.P.

    1996-01-01

    We calculate the three-dimensional depletion field profile in a semiconductor, for a planar semiconductor material with a spatially varying potential upon the surface, and for a tip-shaped semiconductor with a constant surface potential. The nonuniform electric field gives rise to focusing or

  20. Nonlinear Elasticity of Doped Semiconductors

    Science.gov (United States)

    2017-02-01

    AFRL-RY-WP-TR-2016-0206 NONLINEAR ELASTICITY OF DOPED SEMICONDUCTORS Mark Dykman and Kirill Moskovtsev Michigan State University...2016 4. TITLE AND SUBTITLE NONLINEAR ELASTICITY OF DOPED SEMICONDUCTORS 5a. CONTRACT NUMBER FA8650-16-1-7600 5b. GRANT NUMBER 5c. PROGRAM...vibration amplitude. 15. SUBJECT TERMS semiconductors , microresonators, microelectromechanical 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

  1. Semi-conductor rectifiers

    International Nuclear Information System (INIS)

    1981-01-01

    A method is described for treating a semiconductor rectifier, comprising: heating the rectifier to a temperature in the range of 100 0 C to 500 0 C, irradiating the rectifier while maintaining its temperature within the said range, and then annealing the rectifier at a temperature of between 280 0 C and 350 0 C for between two and ten hours. (author)

  2. Semiconductor detector physics

    International Nuclear Information System (INIS)

    Equer, B.

    1987-01-01

    Comprehension of semiconductor detectors follows comprehension of some elements of solid state physics. They are recalled here, limited to the necessary physical principles, that is to say the conductivity. P-n and MIS junctions are discussed in view of their use in detection. Material and structure (MOS, p-n, multilayer, ..) are also reviewed [fr

  3. Synthesis and characterization of a new organic semiconductor material

    Energy Technology Data Exchange (ETDEWEB)

    Tiffour, Imane [Laboratoire de Génie Physique, Département de Physique, Université de Tiaret, Tiaret 14000 (Algeria); Faculté des Sciences et Technologies, Université Mustapha Stambouli, Mascara 29000 (Algeria); Dehbi, Abdelkader [Laboratoire de Génie Physique, Département de Physique, Université de Tiaret, Tiaret 14000 (Algeria); Mourad, Abdel-Hamid I., E-mail: ahmourad@uaeu.ac.ae [Mechanical Engineering Department, Faculty of Engineering, United Arab Emirates University, Al-Ain, P.O. Box 15551 (United Arab Emirates); Belfedal, Abdelkader [Faculté des Sciences et Technologies, Université Mustapha Stambouli, Mascara 29000 (Algeria); LPCMME, Département de Physique, Université d' Oran Es-sénia, 3100 Oran (Algeria)

    2016-08-01

    The objective of this study is to create an ideal mixture of Acetaminophen/Curcumin leading to a new and improved semiconductor material, by a study of the electrical, thermal and optical properties. This new material will be compared with existing semiconductor technology to discuss its viability within the industry. The electrical properties were investigated using complex impedance spectroscopy and optical properties were studied by means of UV-Vis spectrophotometry. The electric conductivity σ, the dielectric constant ε{sub r}, the activation energy E{sub a}, the optical transmittance T and the gap energy E{sub g} have been investigated in order to characterize our organic material. The electrical conductivity of the material is approximately 10{sup −5} S/m at room temperature, increasing the temperature causes σ to increase exponentially to approximately 10{sup −4} S/m. The activation energy obtained for the material is equal to 0.49 ± 0.02 ev. The optical absorption spectra show that the investigating material has absorbance in the visible range with a maximum wavelength (λ{sub max}) 424 nm. From analysis, the absorption spectra it was found the optical band gap equal to 2.6 ± 0.02 eV and 2.46 ± 0.02 eV for the direct and indirect transition, respectively. In general, the study shows that the developed material has characteristics of organic semiconductor material that has a promising future in the field of organic electronics and their potential applications, e.g., photovoltaic cells. - Highlights: • Development of a new organic acetaminophen/Curcumin semiconductor material. • The developed material has characteristics of an organic semiconductor. • It has electrical conductivity comparable to available organic semiconductors. • It has high optical transmittance and low permittivity/dielectric constant.

  4. Synthesis and characterization of a new organic semiconductor material

    International Nuclear Information System (INIS)

    Tiffour, Imane; Dehbi, Abdelkader; Mourad, Abdel-Hamid I.; Belfedal, Abdelkader

    2016-01-01

    The objective of this study is to create an ideal mixture of Acetaminophen/Curcumin leading to a new and improved semiconductor material, by a study of the electrical, thermal and optical properties. This new material will be compared with existing semiconductor technology to discuss its viability within the industry. The electrical properties were investigated using complex impedance spectroscopy and optical properties were studied by means of UV-Vis spectrophotometry. The electric conductivity σ, the dielectric constant ε_r, the activation energy E_a, the optical transmittance T and the gap energy E_g have been investigated in order to characterize our organic material. The electrical conductivity of the material is approximately 10"−"5 S/m at room temperature, increasing the temperature causes σ to increase exponentially to approximately 10"−"4 S/m. The activation energy obtained for the material is equal to 0.49 ± 0.02 ev. The optical absorption spectra show that the investigating material has absorbance in the visible range with a maximum wavelength (λ_m_a_x) 424 nm. From analysis, the absorption spectra it was found the optical band gap equal to 2.6 ± 0.02 eV and 2.46 ± 0.02 eV for the direct and indirect transition, respectively. In general, the study shows that the developed material has characteristics of organic semiconductor material that has a promising future in the field of organic electronics and their potential applications, e.g., photovoltaic cells. - Highlights: • Development of a new organic acetaminophen/Curcumin semiconductor material. • The developed material has characteristics of an organic semiconductor. • It has electrical conductivity comparable to available organic semiconductors. • It has high optical transmittance and low permittivity/dielectric constant.

  5. Organic photovoltaics. Technology and market

    International Nuclear Information System (INIS)

    Brabec, Christoph J.

    2004-01-01

    Organic photovoltaics has come into the international research focus during the past three years. Up to now main efforts have focused on the improvement of the solar conversion efficiency, and in recent efforts 5% white light efficiencies on the device level have been realized. Despite this in comparison to inorganic technologies low efficiency, organic photovoltaics is evaluated as one of the future key technologies opening up completely new applications and markets for photovoltaics. The key property which makes organic photovoltaics so attractive is the potential of reel to reel processing on low cost substrates with standard coating and printing processes. In this contribution we discuss the economical and technical production aspects for organic photovoltaics

  6. Influence of solvent on the poly (acrylic acid)-oligo-(ethylene glycol) polymer gel electrolyte and the performance of quasi-solid-state dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Wu, Jihuai; Lan, Zhang; Lin, Jianming; Huang, Miaoliang; Hao, Shancun; Fang, Leqing

    2007-01-01

    The influence of solvents on the property of poly (acrylic acid)-oligo-(ethylene glycol) polymer gel electrolyte and photovoltaic performance of quasi-solid-state dye-sensitized solar cells (DSSCs) were investigated. Solvents or mixed solvents with large donor number enhance the liquid electrolyte absorbency, which further influences the ionic conductivity of polymer gel electrolyte. A polymer gel electrolyte with ionic conductivity of 4.45 mS cm -1 was obtained by using poly (acrylic acid)-oligo-(ethylene glycol) as polymer matrix, and absorbing 30 vol.% N-methyl pyrrolidone and 70 vol.% γ-butyrolactone with 0.5 M NaI and 0.05 M I 2 . By using this polymer gel electrolyte coupling with 0.4 M pyridine additive, a quasi-solid-state dye-sensitized solar cell with conversion efficiency of 4.74% was obtained under irradiation of 100 mW cm -2 (AM 1.5)

  7. Photovoltaic systems in Indonesia

    International Nuclear Information System (INIS)

    Tjaroko, T.; Bakker, P. de

    2001-01-01

    The article discusses the reasons for the slow growth of the photovoltaic industry in Indonesia where more than 100 million people have no access to electricity, but there is an abundance of solar power. There should be considerable scope for solar home systems in particular. Barriers to expansion of the PV market have included the devaluation of the rupee and the failure of many government-initiated projects. It is concluded that at present, the purchasing power of individuals is insufficient for the potential PV market to expand

  8. Photovoltaic in Switzerland

    International Nuclear Information System (INIS)

    Nordmann, Thomas

    1995-01-01

    The adoption of a new article in the Swiss Constitution relating to energy and a 10 year moratorium on nuclear energy by Swiss voters on 23rd September 1990 had political consequences. The Swiss government (Federal Council), supported by the ruling parties, launched a 10 year national programme in November 1990, known as 'Energy 2000'. By the turn of the millennium, photovoltaic grid-connected installations generating a total of 50 MWp should be installed and brought into operation within the context of the Swiss national programme 'Energy 2000'. The local/regional utilities are supporting this ambitious objective by reimbursing the marginal costs of the energy supplied and additional accompanying measures

  9. Bracket for photovoltaic modules

    Science.gov (United States)

    Ciasulli, John; Jones, Jason

    2014-06-24

    Brackets for photovoltaic ("PV") modules are described. In one embodiment, a saddle bracket has a mounting surface to support one or more PV modules over a tube, a gusset coupled to the mounting surface, and a mounting feature coupled to the gusset to couple to the tube. The gusset can have a first leg and a second leg extending at an angle relative to the mounting surface. Saddle brackets can be coupled to a torque tube at predetermined locations. PV modules can be coupled to the saddle brackets. The mounting feature can be coupled to the first gusset and configured to stand the one or more PV modules off the tube.

  10. Photovoltaic panel clamp

    Science.gov (United States)

    Mittan, Margaret Birmingham [Oakland, CA; Miros, Robert H. J. [Fairfax, CA; Brown, Malcolm P [San Francisco, CA; Stancel, Robert [Loss Altos Hills, CA

    2012-06-05

    A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.

  11. Canadian photovoltaic industry directory

    International Nuclear Information System (INIS)

    1998-01-01

    This directory has been prepared to help potential photovoltaic (PV) customers identify Canadian-based companies who can meet their needs, and to help product manufacturers and distributors identify potential new clients and/or partners within the PV industry for new and improved technologies. To assist the reader, an information matrix is provided that identifies the product and service types offered by each firm and its primary clients served. A list of companies by province or territory is also included. The main section lists companies in alphabetical order. Information presented for each includes address, contact person, prime activity, geographic area served, languages in which services are offered, and a brief company profile

  12. Photovoltaics: sunshine and silicon

    Energy Technology Data Exchange (ETDEWEB)

    Stirzaker, Mike

    2006-05-15

    Spain's photovoltaic sector grew rapidly in 2004 only to slow down in 2005. While a State-guaranteed feed-in tariff is in place to drive a take-off, some of the smaller administrative cogs are buckling under the pressure. Projects are being further slowed by soaring world silicon prices and module shortages. Nevertheless, market volume is higher than ever before, and bio capital from both home and abroad is betting that the Spanish take-off is around the corner. (Author)

  13. Organic photovoltaic energy in Japan; Le photovoltaique organique au Japon

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Japan finances research programs on photovoltaic conversion since 1974. Research in this domain is one of the 11 priorities of NEDO, the agency of means of the ministry of economy, trade and industry of Japan. The search for an abatement of production costs and of an increase of cells efficiency is mentioned in NEDO's programs as soon as the beginning of the 1990's. A road map has been defined which foresees photovoltaic energy production costs equivalent to the ones of thermal conversion by 2030, i.e. 7 yen/kWh (4.4 cents of euro/kWh). The use of new materials in dye-sensitized solar cells (DSSC) or organic solar cells, and of new structures (multi-junctions) is explored to reach this objective. The organic photovoltaic technology is more particularly considered for small generation units in mobile or domestic technologies. Japan is particularly in advance in the improvement of DSSC cells efficiency, in particular in the domain of the research on solid electrolytes. Europe seems more in advance in the domain of the new generation of organic solar cells. Therefore, a complementarity may be found between Japan and French teams in the domain of organic solar cells improvement through collaboration programs. (J.S.)

  14. Hybrid Perovskite Thin-Film Photovoltaics: In Situ Diagnostics and Importance of the Precursor Solvate Phases

    KAUST Repository

    Munir, Rahim

    2016-11-07

    Solution-processed hybrid perovskite semiconductors attract a great deal of attention, but little is known about their formation process. The one-step spin-coating process of perovskites is investigated in situ, revealing that thin-film formation is mediated by solid-state precursor solvates and their nature. The stability of these intermediate phases directly impacts the quality and reproducibility of thermally converted perovskite films and their photovoltaic performance.

  15. Hybrid Perovskite Thin-Film Photovoltaics: In Situ Diagnostics and Importance of the Precursor Solvate Phases

    KAUST Repository

    Munir, Rahim; Sheikh, Arif D.; Abdelsamie, Maged; Hu, Hanlin; Yu, Liyang; Zhao, Kui; Kim, Taesoo; El Tall, Omar; Li, Ruipeng; Smilgies, Detlef M.; Amassian, Aram

    2016-01-01

    Solution-processed hybrid perovskite semiconductors attract a great deal of attention, but little is known about their formation process. The one-step spin-coating process of perovskites is investigated in situ, revealing that thin-film formation is mediated by solid-state precursor solvates and their nature. The stability of these intermediate phases directly impacts the quality and reproducibility of thermally converted perovskite films and their photovoltaic performance.

  16. Photovoltaic Product Directory and Buyers Guide

    Energy Technology Data Exchange (ETDEWEB)

    Watts, R.L.; Smith, S.A.; Dirks, J.A.; Mazzucchi, R.P.; Lee, V.E.

    1984-04-01

    The directory guide explains photovoltaic systems briefly and shows what products are available off-the-shelf. Information is given to assist in designing a photovoltaic system and on financial incentives. Help is given for determining if photovoltaic products can meet a particular buyer's needs, and information is provided on actual photovoltaic user's experiences. Detailed information is appended on various financial incentives available from state and federal governments, sources of additional information on photovoltaics, sources of various photovoltaic products, and a listing of addresses of photovoltaic products suppliers. (LEW)

  17. 17th European photovoltaic solar energy conference and exhibition, Munich 22.-26.10.2001

    International Nuclear Information System (INIS)

    Nowak, S.

    2002-01-01

    This report for the Swiss Federal Office of Energy (SFOE) summarises the photovoltaics (PV) conference and exhibition held in Munich in October 2001 from the Swiss point of view. The contributions made by representatives of Swiss institutions and companies are presented including papers on the progress being made in third generation crystalline and multi-crystalline silicon technology, amorphous and micro-crystalline silicon solar cells, thin film solar cells based on compound semiconductors and thermo-photovoltaics. Further papers deal with PV modules on the market, building-integrated solar power systems and new developments in PV systems technology. The exhibition that accompanied the conference, including the 12 Swiss exhibitors who were present, is reviewed as are international market developments. Contributions concerning the application of photovoltaics in developing countries are also reviewed

  18. Method for producing textured substrates for thin-film photovoltaic cells

    Science.gov (United States)

    Lauf, Robert J.

    1994-01-01

    The invention pertains to the production of ceramic substrates used in the manufacture of thin-film photovoltaic cells used for directly converting solar energy to electrical energy. Elongated ribbon-like sheets of substrate precursor containing a mixture of ceramic particulates, a binder, and a plasticizer are formed and then while green provided with a mechanically textured surface region used for supporting the thin film semiconductor of the photovoltaic cell when the sheets of the substrate precursor are subsequently cut into substrate-sized shapes and then sintered. The textured surface pattern on the substrate provides enhanced light trapping and collection for substantially increasing the solar energy conversion efficiency of thin-film photovoltaic cells.

  19. Photovoltaics: systems considerations

    Energy Technology Data Exchange (ETDEWEB)

    Haq, A M

    1982-08-01

    Photovoltaics applications to date and the potential uses and growth of this alternative energy source for the future are examined in the light of present world economic conditions. In addition, a more detailed description is given, illustrating the method by which system sizing and design are calculated and mentioning such factors as local solar radiation and insolation levels, humidity, wind loading and altitude, all of which affect the optimal system size. The role of computer programming in these calculations is also outlined, illustrating the way in which deterioration, battery losses, poor weather etc. can be accounted and compensated for in the systems design process. The elements of the actual systems are also described, including details of the solar cells and arrays, the electronic controls incorporated in the systems and the characteristics of the batteries used. A resume of projected costs and current technological advances in silicon processing techniques is given together with an analysis of present and future growth trends in the photovoltaics industry.

  20. Photovoltaic programme, edition 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This comprehensive publication issued by the Swiss Federal Office of Energy's Photovoltaics (PV) Programme presents an overview (in English) of activities and projects in the photovoltaics research and pilot and demonstration areas in Switzerland for the year 2003. Progress in future solar cell technologies as well as in the area of modules, building integration and system technologies is summarised. Also, national and international co-operation and multi-national pilot and demonstration projects are commented on. Associated projects such as eco-balances for PV systems, forecasting and modelling tools as well as system monitoring tools are discussed. In the area of pilot and demonstration projects, component development, PV integration in sloping roofs, on flat roofs and on facades as well as further PV plant are looked at. Also, measurement campaigns, studies, statistics and other PV-related topics are summarised. This volume presents a list of 92 projects in the PV area including the appropriate Internet links and is completed with a collection of project abstracts.

  1. Photovoltaic programme, edition 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This comprehensive publication issued by the Swiss Federal Office of Energy's Photovoltaics (PV) Programme presents an overview (in English) of activities and projects in the photovoltaics research and pilot and demonstration areas in Switzerland for the year 2003. Progress in future solar cell technologies as well as in the area of modules, building integration and system technologies is summarised. Also, national and international co-operation and multi-national pilot and demonstration projects are commented on. Associated projects such as eco-balances for PV systems, forecasting and modelling tools as well as system monitoring tools are discussed. In the area of pilot and demonstration projects, component development, PV integration in sloping roofs, on flat roofs and on facades as well as further PV plant are looked at. Also, measurement campaigns, studies, statistics and other PV-related topics are summarised. This volume presents a list of 92 projects in the PV area including the appropriate Internet links and is completed with a collection of project abstracts.

  2. Photovoltaics information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marie, T.L.; Reinhardt, C.L.

    1980-10-01

    The results of a series of telephone interviews with groups of users of information on photovoltaics (PV) are described. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The report is 1 of 10 discussing study results. The overall study provides baseline data about information needs in the solar community. It covers these technological areas: photovoltaics, passive solar heating and cooling, active solar heating and cooling, biomass energy, solar thermal electric power, solar industrial and agricultural process heat, wind energy, ocean energy, and advanced energy storage. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from seven PV groups respondents are analyzed in this report: DOE-Funded Researchers, Non-DOE-Funded Researchers, Researchers Working for Manufacturers, Representatives of Other Manufacturers, Representatives of Utilities, Electric Power Engineers, and Educators.

  3. The Effects of Cells Temperature Increment and Variations of Irradiation for Monocrystalline Photovoltaic

    Science.gov (United States)

    Fuad Rahman Soeharto, Faishal; Hermawan

    2017-04-01

    Photovoltaic cell technology has been developed to meet the target of 17% Renewable Energy in 2025 accordance with Indonesia Government Regulation No. 5 2006. Photovoltaic cells are made of semiconductor materials, namely silicon or germanium (p-n junction). These cells need the light that comes from solar irradiation which brings energy photons to convert light energy into electrical energy. It is different from the solar heater that requires heat energy or thermal of sunlight that is normally used for drying or heating water. Photovoltaic cells requires energy photons to perform the energy conversion process, the photon energy can be derived from sunlight. Energy photon is taken from the sun light along with the advent of heat due to black-body radiation, which can lead to temperature increments of photovoltaic cells. Increment of 1°C can decreased photovoltaic cell voltage of up to 2.3 mV per cell. In this research, it will be discuss the analysis of the effect of rising temperatures and variations of irradiation on the type monocrystalline photovoltaic. Those variation are analyzed, simulated and experiment by using a module of experiment. The test results show that increment temperature from 25° C to 80° C at cell of photovoltaic decrease the output voltage of the photovoltaic cell at 4.21 V, and it also affect the power output of the cell which decreases up to 0.7523 Watt. In addition, the bigger the value of irradiation received by cell at amount of 1000 W / m2, produce more output power cells at the same temperature.

  4. Characterization of silica quartz as raw material in photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Boussaa, S. Anas, E-mail: sabiha.anas@gmail.com; Kheloufi, A.; Kefaifi, A.; Kerkar, F. [Division croissance cristalline et procédés métallurgiques CCPM Centre de recherche en technologie des semi-conducteurs pour l’énergétique (C.R.T.S.E) 02 Bd Frantz Fanon BP. 140 Alger 7 merveilles, Alger 16200 (Algeria); Zaourar, N. Boutarek [Laboratoire des technologies des matériaux, USTHB, B.P. 32 El Alia, Bab Ezzouar, Alger, Algérie 16111 (Algeria)

    2016-07-25

    Raw materials are essential for the functioning of modern societies, and access to these raw materials is vital to the world economy. Sustainable development, both globally level, raises important new challenges associated with access and efficient use of raw materials. High purity quartz, is consider as a critical raw material and it is a rare commodity that only forms under geological conditions where a narrow set of chemical and physical parameters is fulfilled. When identified and following special beneficiation techniques, high purity quartz obtains very attractive prices and is applied in high technology sectors that currently are under rapid expansion such as photovoltaic solar cells, silicon metal - oxide wafers in the semiconductor industry and long distance optical fibers that are used in communication networks. Crystalline silicon remains the principal material for photovoltaic technology. Metallurgical silicon is produced industrially by the reduction of silica with carbon in an electric arc furnace at temperatures higher than 2000 °C in the hottest parts, by a reaction that can be written ideally as: SiO{sub 2} + 2C = Si + 2CO. The aim of this study has been to test experimental methods for investigating the various physical and chemical proprieties of Hoggar quartz with different techniques: X Ray Fluorescence, infra-red spectroscopy, Scanning Electron Microscopy, Optic Microscopy, Carbon Analyzer and Vickers Hardness. The results show finally that the quartz has got good result in purity but need enrichment for the photovoltaic application.

  5. Understanding the physical properties of hybrid perovskites for photovoltaic applications

    Science.gov (United States)

    Huang, Jinsong; Yuan, Yongbo; Shao, Yuchuan; Yan, Yanfa

    2017-07-01

    New photovoltaic materials have been searched for in the past decades for clean and renewable solar energy conversion with an objective of reducing the levelized cost of electricity (that is, the unit price of electricity over the course of the device lifetime). An emerging family of semiconductor materials — organic-inorganic halide perovskites (OIHPs) — are the focus of the photovoltaic research community owing to their use of low cost, nature-abundant raw materials, low-temperature and scalable solution fabrication processes, and, in particular, the very high power conversion efficiencies that have been achieved within the short time of their development. In this Review, we summarize and critically assess the most recent advances in understanding the physical properties of both 3D and low-dimensional OIHPs that favour a small open-circuit voltage deficit and high power conversion efficiency. Several prominent topics in this field on the unique properties of OIHPs are surveyed, including defect physics, ferroelectricity, exciton dissociation processes, carrier recombination lifetime and photon recycling. The impact of ion migration on solar cell efficiency and stability are also critically analysed. Finally, we discuss the remaining challenges in the commercialization of OIHP photovoltaics.

  6. Infrared Colloidal Quantum Dots for Photovoltaics: Fundamentals and Recent Progress

    KAUST Repository

    Tang, Jiang

    2010-09-14

    Colloidal quantum dots (CQDs) are solution-processed semiconductors of interest in low-cost photovoltaics. Tuning of the bandgap of CQD films via the quantum size effect enables customization of solar cells\\' absorption profile to match the sun\\'s broad visible- and infrared-containing spectrum reaching the earth. Here we review recent progress in the realization of low-cost, efficient solar cells based on CQDs. We focus in particular on CQD materials and approaches that provide both infrared and visible-wavelength solar power conversion CQD photovoltaics now exceed 5% solar power conversion efficiency, achieved by the introduction of a new architecture, the depleted-heterojunction CQD solar cell, that jointly maximizes current, voltage, and fill factor. CQD solar cells have also seen major progress in materials processing for stability, recently achieving extended operating lifetimes in an air ambient. We summarize progress both in device operation and also in gaining new insights into materials properties and processing - including new electrical contact materials and deposition techniques, as well as CQD synthesis, surface treatments, film-forming technologies - that underpin these rapid advances. Infrared colloidal quantum dots that absorb most of the solar radiation enable potential efficient and low-cost photovoltaic devices. Careful optimization of quantum dot passivation and device configuration leads to solar cells with AM1.5G efficiency as high as 5.1% Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Parametric study of laser photovoltaic energy converters

    Science.gov (United States)

    Walker, G. H.; Heinbockel, J. H.

    1987-01-01

    Photovoltaic converters are of interest for converting laser power to electrical power in a space-based laser power system. This paper describes a model for photovoltaic laser converters and the application of this model to a neodymium laser silicon photovoltaic converter system. A parametric study which defines the sensitivity of the photovoltaic parameters is described. An optimized silicon photovoltaic converter has an efficiency greater than 50 percent for 1000 W/sq cm of neodymium laser radiation.

  8. The optical characterization of organometallic complex thin films by spectroscopic ellipsometry and photovoltaic diode application

    Energy Technology Data Exchange (ETDEWEB)

    Özaydın, C. [Batman University, Engineering Faculty, Department of Computer Eng., Batman (Turkey); Güllü, Ö., E-mail: omergullu@gmail.com [Batman University, Science and Art Faculty, Department of Physics, Batman (Turkey); Pakma, O. [Batman University, Science and Art Faculty, Department of Physics, Batman (Turkey); Ilhan, S. [Siirt University, Science and Art Faculty, Department of Chemistry, Siirt (Turkey); Akkılıç, K. [Dicle University, Education Faculty, Department of Physics Education, Diyarbakır (Turkey)

    2016-05-15

    Highlights: • Optical properties and thickness of the A novel organometallic complex (OMC) film were investigated by spectroscopic ellipsometry (SE). • Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated • This paper presents the I–V analysis of Au/OMC/n-Si MIS diode. • Current–voltage and photovoltaic properties of the diode were investigated. - Abstract: In this work, organometallic complex (OMC) films have been deposited onto glass or silicon substrates by spin coating technique and their photovoltaic application potential has been investigated. Optical properties and thickness of the film have been investigated by spectroscopic ellipsometry (SE). Also, transmittance spectrum has been taken by UV/vis spectrophotometer. The optical method has been used to determine the band gap value of the films. Also, Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated. Current–voltage and photovoltaic properties of the structure were investigated. The ideality factor (n) and barrier height (Φ{sub b}) values of the diode were found to be 2.89 and 0.79 eV, respectively. The device shows photovoltaic behavior with a maximum open-circuit voltage of 396 mV and a short circuit current of 33.8 μA under 300 W light.

  9. The optical characterization of organometallic complex thin films by spectroscopic ellipsometry and photovoltaic diode application

    International Nuclear Information System (INIS)

    Özaydın, C.; Güllü, Ö.; Pakma, O.; Ilhan, S.; Akkılıç, K.

    2016-01-01

    Highlights: • Optical properties and thickness of the A novel organometallic complex (OMC) film were investigated by spectroscopic ellipsometry (SE). • Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated • This paper presents the I–V analysis of Au/OMC/n-Si MIS diode. • Current–voltage and photovoltaic properties of the diode were investigated. - Abstract: In this work, organometallic complex (OMC) films have been deposited onto glass or silicon substrates by spin coating technique and their photovoltaic application potential has been investigated. Optical properties and thickness of the film have been investigated by spectroscopic ellipsometry (SE). Also, transmittance spectrum has been taken by UV/vis spectrophotometer. The optical method has been used to determine the band gap value of the films. Also, Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated. Current–voltage and photovoltaic properties of the structure were investigated. The ideality factor (n) and barrier height (Φ_b) values of the diode were found to be 2.89 and 0.79 eV, respectively. The device shows photovoltaic behavior with a maximum open-circuit voltage of 396 mV and a short circuit current of 33.8 μA under 300 W light.

  10. Optical properties of Sb(Se,Te)I and photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Tablero, C., E-mail: ctablero@etsit.upm.es

    2016-09-05

    SbXI (X = Se, Te) are ferroelectric semiconductors that allow a variety of applications including optoelectronic and photovoltaic applications. An analysis of the optical properties is carried out starting from first-principles density-functional theory with orbital-dependent one-electron potentials. To go into the contributions to the optical properties more deeply, the absorption coefficients have been split into inter- and intra-species contributions and into atomic angular momentum contributions. The optical results are used to evaluate the efficiencies when this material is used to absorb sunlight at several sunlight concentrations and the usual radiative and the ferroelectric photovoltaic mechanisms. The results indicate their applicability in photovoltaic devices as absorbent of the solar spectrum with high conversion efficiency. - Highlights: • The SbXI (X = Se, Te) are ferroelectric semiconductors with a high optical absorption. • The absorption coefficients have been split into different contributions to understand the cause of the high absorption. • Using the first-principles results the maximum efficiency of this photovoltaic absorber material has been estimated. • The efficiency of this compound is near the maximum efficiency for single-gap solar cells even using small-width devices. • The coexistence of the R-PV and R-PV effects has been evaluated.

  11. Semiconductor-based, large-area, flexible, electronic devices on {110} oriented substrates

    Science.gov (United States)

    Goyal, Amit

    2014-08-05

    Novel articles and methods to fabricate the same resulting in flexible, oriented, semiconductor-based, electronic devices on {110} textured substrates are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  12. [100] or [110] aligned, semiconductor-based, large-area, flexible, electronic devices

    Science.gov (United States)

    Goyal, Amit

    2015-03-24

    Novel articles and methods to fabricate the same resulting in flexible, large-area, [100] or [110] textured, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  13. {100} or 45.degree.-rotated {100}, semiconductor-based, large-area, flexible, electronic devices

    Science.gov (United States)

    Goyal, Amit [Knoxville, TN

    2012-05-15

    Novel articles and methods to fabricate the same resulting in flexible, {100} or 45.degree.-rotated {100} oriented, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  14. Amorphous Semiconductors: From Photocatalyst to Computer Memory

    Science.gov (United States)

    Sundararajan, Mayur

    encouraging but inconclusive. Then the method was successfully demonstrated on mesoporous TiO2SiO 2 by showing a shift in its optical bandgap. One of the special class of amorphous semiconductors is chalcogenide glasses, which exhibit high ionic conductivity even at room temperature. When metal doped chalcogenide glasses are under an electric field, they become electronically conductive. These properties are exploited in the computer memory storage application of Conductive Bridging Random Access Memory (CBRAM). CBRAM is a non-volatile memory that is a strong contender to replace conventional volatile RAMs such as DRAM, SRAM, etc. This technology has already been commercialized, but the working mechanism is still not clearly understood especially the nature of the conductive bridge filament. In this project, the CBRAM memory cells are fabricated by thermal evaporation method with Agx(GeSe 2)1-x as the solid electrolyte layer, Ag as the active electrode and Au as the inert electrode. By careful use of cyclic voltammetry, the conductive filaments were grown on the surface and the bulk of the solid electrolyte. The comparison between the two filaments revealed major differences leading to contradiction with the existing working mechanism. After compiling all the results, a modified working mechanism is proposed. SAXS is a powerful tool to characterize nanostructure of glasses. The analysis of the SAXS data to get useful information are usually performed by different programs. In this project, Irena and GIFT programs were compared by performing the analysis of the SAXS data of glass and glass ceramics samples. Irena was shown to be not suitable for the analysis of SAXS data that has a significant contribution from interparticle interactions. GIFT was demonstrated to be better suited for such analysis. Additionally, the results obtained by programs for samples with low interparticle interactions were shown to be consistent.

  15. Multivalent weak electrolytes - risky background electrolytes for capillary zone electrophoresis

    Czech Academy of Sciences Publication Activity Database

    Beckers, J. L.; Boček, Petr

    2002-01-01

    Roč. 23, č. 12 (2002), s. 1942-1946 ISSN 0173-0835 R&D Projects: GA ČR GA203/99/0044; GA ČR GA203/02/0023; GA ČR GA203/01/0401; GA AV ČR IAA4031703; GA AV ČR IAA4031103 Institutional research plan: CEZ:AV0Z4031919 Keywords : background electrolytes * capillary zone electrophoresis * multivalent electrolytes Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.325, year: 2002

  16. Single frequency semiconductor lasers

    CERN Document Server

    Fang, Zujie; Chen, Gaoting; Qu, Ronghui

    2017-01-01

    This book systematically introduces the single frequency semiconductor laser, which is widely used in many vital advanced technologies, such as the laser cooling of atoms and atomic clock, high-precision measurements and spectroscopy, coherent optical communications, and advanced optical sensors. It presents both the fundamentals and characteristics of semiconductor lasers, including basic F-P structure and monolithic integrated structures; interprets laser noises and their measurements; and explains mechanisms and technologies relating to the main aspects of single frequency lasers, including external cavity lasers, frequency stabilization technologies, frequency sweeping, optical phase locked loops, and so on. It paints a clear, physical picture of related technologies and reviews new developments in the field as well. It will be a useful reference to graduate students, researchers, and engineers in the field.

  17. Basic semiconductor physics

    CERN Document Server

    Hamaguchi, Chihiro

    2017-01-01

    This book presents a detailed description of basic semiconductor physics. The text covers a wide range of important phenomena in semiconductors, from the simple to the advanced. Four different methods of energy band calculations in the full band region are explained: local empirical pseudopotential, non-local pseudopotential, KP perturbation and tight-binding methods. The effective mass approximation and electron motion in a periodic potential, Boltzmann transport equation and deformation potentials used for analysis of transport properties are discussed. Further, the book examines experiments and theoretical analyses of cyclotron resonance in detail. Optical and transport properties, magneto-transport, two-dimensional electron gas transport (HEMT and MOSFET) and quantum transport are reviewed, while optical transition, electron-phonon interaction and electron mobility are also addressed. Energy and electronic structure of a quantum dot (artificial atom) are explained with the help of Slater determinants. The...

  18. Semiconductor physics an introduction

    CERN Document Server

    Seeger, Karlheinz

    1999-01-01

    Semiconductor Physics - An Introduction - is suitable for the senior undergraduate or new graduate student majoring in electrical engineering or physics. It will also be useful to solid-state scientists and device engineers involved in semiconductor design and technology. The text provides a lucid account of charge transport, energy transport and optical processes, and a detailed description of many devices. It includes sections on superlattices and quantum well structures, the effects of deep-level impurities on transport, the quantum Hall effect and the calculation of the influence of a magnetic field on the carrier distribution function. This 6th edition has been revised and corrected, and new sections have been added to different chapters.

  19. Three dimensional strained semiconductors

    Science.gov (United States)

    Voss, Lars; Conway, Adam; Nikolic, Rebecca J.; Leao, Cedric Rocha; Shao, Qinghui

    2016-11-08

    In one embodiment, an apparatus includes a three dimensional structure comprising a semiconductor material, and at least one thin film in contact with at least one exterior surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the three dimensional structure. In another embodiment, a method includes forming a three dimensional structure comprising a semiconductor material, and depositing at least one thin film on at least one surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the structure.

  20. Compound semiconductor device modelling

    CERN Document Server

    Miles, Robert

    1993-01-01

    Compound semiconductor devices form the foundation of solid-state microwave and optoelectronic technologies used in many modern communication systems. In common with their low frequency counterparts, these devices are often represented using equivalent circuit models, but it is often necessary to resort to physical models in order to gain insight into the detailed operation of compound semiconductor devices. Many of the earliest physical models were indeed developed to understand the 'unusual' phenomena which occur at high frequencies. Such was the case with the Gunn and IMPATI diodes, which led to an increased interest in using numerical simulation methods. Contemporary devices often have feature sizes so small that they no longer operate within the familiar traditional framework, and hot electron or even quantum­ mechanical models are required. The need for accurate and efficient models suitable for computer aided design has increased with the demand for a wider range of integrated devices for operation at...

  1. Optically coupled semiconductor device

    Energy Technology Data Exchange (ETDEWEB)

    Kumagaya, Naoki

    1988-11-18

    This invention concerns an optically coupled semiconductor device using the light as input signal and a MOS transistor for the output side in order to control on-off of the output side by the input signal which is insulated from the output. Concerning this sort of element, when a MOS transistor and a load resistance are planned to be accumulated on the same chip, a resistor and control of impurity concentration of the channel, etc. become necessary despite that the only formation of a simple P-N junction is enough, for a solar cell, hence cost reduction thereof cannot be done. In order to remove this defect, this invention offers an optically coupled semiconductor device featuring that two solar cells are connected in reverse parallel between the gate sources of the output MOS transistors and an operational light emitting element is individually set facing a respective solar cell. 4 figs.

  2. Semiconductor thermoelectric generators

    CERN Document Server

    Fahrner, Wolfgang R

    2009-01-01

    It is well-known that fossil fuels are being rapidly depleted, and that atomic power is rejected by many people. As a consequence, there is a strong trend towards alternative sources such as wind, photovoltaics, solar heat and biomass. Strangely enough, quite another power source is generally neglected: namely, the thermoelectric generator (a device which converts heat, i.e. thermal energy, directly into electrical energy). The reason for this neglect is probably the low conversion efficiency, which is of the order of a few percent at most. However, there are two arguments in favor of the ther

  3. Photovoltaic module with adhesion promoter

    Science.gov (United States)

    Xavier, Grace

    2013-10-08

    Photovoltaic modules with adhesion promoters and methods for fabricating photovoltaic modules with adhesion promoters are described. A photovoltaic module includes a solar cell including a first surface and a second surface, the second surface including a plurality of interspaced back-side contacts. A first glass layer is coupled to the first surface by a first encapsulating layer. A second glass layer is coupled to the second surface by a second encapsulating layer. At least a portion of the second encapsulating layer is bonded directly to the plurality of interspaced back-side contacts by an adhesion promoter.

  4. Photovoltaics - why this 'religious war'?

    International Nuclear Information System (INIS)

    Nowak, S.

    2005-01-01

    This article examines the possible reasons behind controversies concerning photovoltaics in Switzerland. The author, who considers that no other energy technology awakes such varying opinions, presents ten points that should be considered in this connection. These include aspects concerning research and development, trade and industry as well as markets and applications. The 'enormous' potential of photovoltaics and questions concerning availability and environmental issues are discussed. Costs, developments and the question of economic viability are looked at. The situation in Switzerland is compared with international conditions. Finally, political issues are reviewed and the key role to be played by photovoltaics in the future is stressed

  5. Radioisotope-powered photovoltaic generator

    International Nuclear Information System (INIS)

    McKlveen, J.W.; Uselman, J.

    1979-01-01

    Disposing of radioactive wastes from nuclear power plants has become one of the most important issues facing the nuclear industry. In a new concept, called a radioisotope photovoltaic generator, a portion of this waste would be used in conjunction with a scintillation material to produce light, with subsequent conversion into electricity via photovoltaic cells. Three types of scintillators and two types of silicon cells were tested in six combinations using 32 P as the radioisotope. The highest system efficiency, determined to be 0.5% when the light intensity was normalized to 100 mW/cm 2 , was obtained using a CsI crystal scintillator and a Helios photovoltaic cell

  6. Optimization of photovoltaic power systems

    CERN Document Server

    Rekioua, Djamila

    2012-01-01

    Photovoltaic generation is one of the cleanest forms of energy conversion available. One of the advantages offered by solar energy is its potential to provide sustainable electricity in areas not served by the conventional power grid. Optimisation of Photovoltaic Power Systems details explicit modelling, control and optimisation of the most popular stand-alone applications such as pumping, power supply, and desalination. Each section is concluded by an example using the MATLAB(R) and Simulink(R) packages to help the reader understand and evaluate the performance of different photovoltaic syste

  7. Images through semiconductors

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Improved image processing techniques are constantly being developed for television and for scanners using X-rays or other radiation for industrial or medical applications, etc. As Erik Heijne of CERN explains here, particle physics too has its own special requirements for image processing. The increasing use of semiconductor techniques for handling measurements down to the level of a few microns provides another example of the close interplay between scientific research and technological development. (orig.).

  8. Muonium states in semiconductors

    International Nuclear Information System (INIS)

    Patterson, B.D.

    1987-01-01

    There is a brief summary of what is known about the muonium states isotropic, anisotropic and diamagnetic in diamond and zincblende semiconductors. The report deals with muonium spectroscopy, including the formation probabilities, hyperfine parameters and electronic g-factors of the states. The dynamics of the states is treated including a discussion of the transition from isotropic Mu to anisotropic Mu in diamond, temperature-dependent linewidthes in silicon and germanium and effects of daping and radiation damage

  9. Nonradiative recombination in semiconductors

    CERN Document Server

    Abakumov, VN; Yassievich, IN

    1991-01-01

    In recent years, great progress has been made in the understandingof recombination processes controlling the number of excessfree carriers in semiconductors under nonequilibrium conditions. As a result, it is now possible to give a comprehensivetheoretical description of these processes. The authors haveselected a number of experimental results which elucidate theunderlying physical problems and enable a test of theoreticalmodels. The following topics are dealt with: phenomenological theory ofrecombination, theoretical models of shallow and deep localizedstates, cascade model of carrier captu

  10. Isotopically controlled semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Haller, Eugene E.

    2006-06-19

    The following article is an edited transcript based on the Turnbull Lecture given by Eugene E. Haller at the 2005 Materials Research Society Fall Meeting in Boston on November 29, 2005. The David Turnbull Lectureship is awarded to recognize the career of a scientist who has made outstanding contributions to understanding materials phenomena and properties through research, writing, and lecturing, as exemplified by the life work of David Turnbull. Haller was named the 2005 David Turnbull Lecturer for his 'pioneering achievements and leadership in establishing the field of isotopically engineered semiconductors; for outstanding contributions to materials growth, doping and diffusion; and for excellence in lecturing, writing, and fostering international collaborations'. The scientific interest, increased availability, and technological promise of highly enriched isotopes have led to a sharp rise in the number of experimental and theoretical studies with isotopically controlled semiconductor crystals. This article reviews results obtained with isotopically controlled semiconductor bulk and thin-film heterostructures. Isotopic composition affects several properties such as phonon energies, band structure, and lattice constant in subtle, but, for their physical understanding, significant ways. Large isotope-related effects are observed for thermal conductivity in local vibrational modes of impurities and after neutron transmutation doping. Spectacularly sharp photoluminescence lines have been observed in ultrapure, isotopically enriched silicon crystals. Isotope multilayer structures are especially well suited for simultaneous self- and dopant-diffusion studies. The absence of any chemical, mechanical, or electrical driving forces makes possible the study of an ideal random-walk problem. Isotopically controlled semiconductors may find applications in quantum computing, nanoscience, and spintronics.

  11. Survey of semiconductor physics

    CERN Document Server

    Böer, Karl W

    1992-01-01

    Any book that covers a large variety of subjects and is written by one author lacks by necessity the depth provided by an expert in his or her own field of specialization. This book is no exception. It has been written with the encouragement of my students and colleagues, who felt that an extensive card file I had accumulated over the years of teaching solid state and semiconductor physics would be helpful to more than just a few of us. This file, updated from time to time, contained lecture notes and other entries that were useful in my research and permitted me to give to my students a broader spectrum of information than is available in typical textbooks. When assembling this material into a book, I divided the top­ ics into material dealing with the homogeneous semiconductor, the subject of the previously published Volume 1, and the inhomoge­ neous semiconductor, the subject of this Volume 2. In order to keep the book to a manageable size, sections of tutorial character which can be used as text for a g...

  12. Semiconductor Ion Implanters

    International Nuclear Information System (INIS)

    MacKinnon, Barry A.; Ruffell, John P.

    2011-01-01

    In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion! Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  13. The Physics of Semiconductors

    Science.gov (United States)

    Brennan, Kevin F.

    1999-02-01

    Modern fabrication techniques have made it possible to produce semiconductor devices whose dimensions are so small that quantum mechanical effects dominate their behavior. This book describes the key elements of quantum mechanics, statistical mechanics, and solid-state physics that are necessary in understanding these modern semiconductor devices. The author begins with a review of elementary quantum mechanics, and then describes more advanced topics, such as multiple quantum wells. He then disusses equilibrium and nonequilibrium statistical mechanics. Following this introduction, he provides a thorough treatment of solid-state physics, covering electron motion in periodic potentials, electron-phonon interaction, and recombination processes. The final four chapters deal exclusively with real devices, such as semiconductor lasers, photodiodes, flat panel displays, and MOSFETs. The book contains many homework exercises and is suitable as a textbook for electrical engineering, materials science, or physics students taking courses in solid-state device physics. It will also be a valuable reference for practicing engineers in optoelectronics and related areas.

  14. Polymer Electrolyte Membranes for Water Photo-Electrolysis

    Science.gov (United States)

    Aricò, Antonino S.; Girolamo, Mariarita; Siracusano, Stefania; Sebastian, David; Baglio, Vincenzo; Schuster, Michael

    2017-01-01

    Water-fed photo-electrolysis cells equipped with perfluorosulfonic acid (Nafion® 115) and quaternary ammonium-based (Fumatech® FAA3) ion exchange membranes as separator for hydrogen and oxygen evolution reactions were investigated. Protonic or anionic ionomer dispersions were deposited on the electrodes to extend the interface with the electrolyte. The photo-anode consisted of a large band-gap Ti-oxide semiconductor. The effect of membrane characteristics on the photo-electrochemical conversion of solar energy was investigated for photo-voltage-driven electrolysis cells. Photo-electrolysis cells were also studied for operation under electrical bias-assisted mode. The pH of the membrane/ionomer had a paramount effect on the photo-electrolytic conversion. The anionic membrane showed enhanced performance compared to the Nafion®-based cell when just TiO2 anatase was used as photo-anode. This was associated with better oxygen evolution kinetics in alkaline conditions compared to acidic environment. However, oxygen evolution kinetics in acidic conditions were significantly enhanced by using a Ti sub-oxide as surface promoter in order to facilitate the adsorption of OH species as precursors of oxygen evolution. However, the same surface promoter appeared to inhibit oxygen evolution in an alkaline environment probably as a consequence of the strong adsorption of OH species on the surface under such conditions. These results show that a proper combination of photo-anode and polymer electrolyte membrane is essential to maximize photo-electrolytic conversion. PMID:28468242

  15. A Novel Polymer Electrolyte Using In-situ Quanternization for All Solid-state Dye-sensitized Solar Cell

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    1 Introduction Dye-sensitized solar cells (DSSCs) with a mesoporous network of interconnected TiO2 nanocrystals have attracted wide-spread scientific and technological interest over the past decades due to its low cost and high energy conversion efficiency. Meantime, it also has been considered as potential alternative to conventional photovoltaic devices. In 2001, Gratzel group constructed such kind of DSSC with the conversion efficiency of more than 11%[1]. But this system uses liquid electrolyte with...

  16. Estimates of occupational safety and health impacts resulting from large-scale production of major photovoltaic technologies

    Energy Technology Data Exchange (ETDEWEB)

    Owens, T.; Ungers, L.; Briggs, T.

    1980-08-01

    The purpose of this study is to estimate both quantitatively and qualitatively, the worker and societal risks attributable to four photovoltaic cell (solar cell) production processes. Quantitative risk values were determined by use of statistics from the California semiconductor industry. The qualitative risk assessment was performed using a variety of both governmental and private sources of data. The occupational health statistics derived from the semiconductor industry were used to predict injury and fatality levels associated with photovoltaic cell manufacturing. The use of these statistics to characterize the two silicon processes described herein is defensible from the standpoint that many of the same process steps and materials are used in both the semiconductor and photovoltaic industries. These health statistics are less applicable to the gallium arsenide and cadmium sulfide manufacturing processes, primarily because of differences in the materials utilized. Although such differences tend to discourage any absolute comparisons among the four photovoltaic cell production processes, certain relative comparisons are warranted. To facilitate a risk comparison of the four processes, the number and severity of process-related chemical hazards were assessed. This qualitative hazard assessment addresses both the relative toxicity and the exposure potential of substances in the workplace. In addition to the worker-related hazards, estimates of process-related emissions and wastes are also provided.

  17. Photovoltaic building blocks

    DEFF Research Database (Denmark)

    Hanberg, Peter Jesper; Jørgensen, Anders Michael

    2014-01-01

    efficiency of about 15% for commercial Silicon solar cells there is still much to gain. DTU Danchip provides research facilities, equipment and expertise for the building blocks that comprises fabricating the efficient solar cell. In order to get more of the sun light into the device we provide thin film......Photovoltaics (PV), better known as solar cells, are now a common day sight on many rooftops in Denmark.The installed capacity of PV systems worldwide is growing exponentially1 and is the third most importantrenewable energy source today. The cost of PV is decreasing fast with ~10%/year but to make...... it directcompetitive with fossil energy sources a further reduction is needed. By increasing the efficiency of the solar cells one gain an advantage through the whole chain of cost. So that per produced Watt of power less material is spent, installation costs are lower, less area is used etc. With an average...

  18. Photovoltaic module mounting system

    Science.gov (United States)

    Miros, Robert H. J. [Fairfax, CA; Mittan, Margaret Birmingham [Oakland, CA; Seery, Martin N [San Rafael, CA; Holland, Rodney H [Novato, CA

    2012-04-17

    A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

  19. Photovoltaic static concentrator analysis

    Science.gov (United States)

    Almonacid, G.; Luque, A.; Molledo, A. G.

    1984-12-01

    Ray tracing is the basis of the present analysis of truncated bifacial compound parabolic concentrators filled with a dielectric substance, which are of interest in photovoltaic applications where the bifacial cells allow higher static concentrations to be achieved. Among the figures of merit for this type of concentrator, the directional intercept factor plays a major role and is defined as the ratio of the power of the collector to that at the entry aperture, in a lossless concentrator illuminated by light arriving from a given direction. A procedure for measuring outdoor, full size panels has been developed, and a correction method for avoiding the effect of unwanted diffuse radiation during the measurements is presented.

  20. The photovoltaic industry stunned

    International Nuclear Information System (INIS)

    Piro, P.

    2011-01-01

    In December 2010 the French authorities decided a 3-month moratory on any new project of photovoltaic installation (over 3 KWc) because of the huge number of demands that made the cost of the incentive measures soar in an unexpected manner. In March 2011 the moratory was lifted and the professionals have been stunned by the new conditions imposed to benefit from the preferential purchase tariffs of the electricity produced that are far less favourable than previously. The new tariff grid will be adjusted each term according to the volume of demands. While several thousand jobs are at stake, the professionals hope a reversal of the government position as France enters an electoral period. (A.C.)

  1. The solar photovoltaic

    International Nuclear Information System (INIS)

    2016-02-01

    This publication first outlines challenges and stakes related to the development of renewable energies, and more particularly of photovoltaic solar energy in France and in the World. Principles and applications (connected and autonomous systems) are briefly presented. Some key data regarding installed capacity and its evolution in France and in other countries are briefly commented. The knowledge status of this technology is discussed in terms of strengths (environmental and energetic benefits, modularity, fast decreasing costs, integration into building envelope, local investment and consumer commitment, an added value and job generating sector), and weaknesses (fluctuating production and impact on the supply-demand balance, local impact on the distribution grid, land use, cautions, a sector with some environmental impact, evolutions of the support arrangement in France). Actions undertaken by the ADEME in different areas (support to research and innovation, installation quality, promotion of technologies with less environmental impacts) are reviewed

  2. 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.

  3. Photovoltaic solar concentrator

    Science.gov (United States)

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

    2016-03-15

    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.

  4. Technology fundamentals: photovoltaic systems

    International Nuclear Information System (INIS)

    Quaschning, V.

    2006-01-01

    The generation of electric power from photovoltaic systems is described in detail. The mechanism of operation of solar cells is described in terms of photons, electrons, charge carriers and charge separation. The various cells, modules, technical terms and related technology are discussed. The chemical elements used in solar cells are mentioned and the manufacturing processes described. The technical advantages of the newer thin-film modules over the traditional silicon cells are given but at present manufacturing cost is limiting their production. Both stand-alone and grid-connected PV systems are described. The potential market for PV systems is discussed. It is suggested that PV could eventually meet the total global electric power demand. (author)

  5. Photovoltaic demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Gillett, W B; Hacker, R J; Kaut, W [eds.

    1991-01-01

    This book, the proceedings of the fourth PV-Contractors' Meeting organized by the Commission of the European Communities, Directorate-General for Energy, held at Brussels on 21 and 22 November 1989, provides an overview of the photovoltaic demonstration projects which have been supported in the framework of the Energy Demonstration Program since 1983. It includes reports by each of the contractors who submitted proposals in 1983, 1984, 1985 and 1986, describing progress with their projects. Summaries of the discussions held at the meeting, which included contractors whose projects were submitted in 1987, are also presented. The different technologies which are being demonstrated concern the modules, the cabling of the array, structure design, storage strategy and power conditioning. The various applications include desalination, communications, dairy farms, water pumping, and warning systems. Papers have been processed separately for inclusion on the data base.

  6. Photovoltaic demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Kaut, W [Commission of the European Communities, Brussels (Belgium); Gillett, W B; Hacker, R J [Halcrow Gilbert Associates Ltd., Swindon (GB)

    1992-12-31

    This publication, comprising the proceedings of the fifth contractor`s meeting organized by the Commission of the European Communities, Directorate-General for Energy, provides an overview of the photovoltaic demonstration projects which have been supported in the framework of the energy demonstration programme since 1983. It includes reports by each of the contractors who submitted proposals in 1987 and 1988, describing progress within their projects. Projects accepted from earlier calls for proposals and not yet completed were reviewed by a rapporteur and are discussed in the summary section. The results of the performance monitoring of all projects and the lessons drawn from the practical experience of the projects are also presented in the summaries and conclusions. Contractors whose projects were submitted in 1989 were also present at the meeting and contributed to the reported discussions. This proceeding is divided into four sessions (General, Housing, technical presentations, other applications) and 24 papers are offered.

  7. Energizing architecture. Design and photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Lueling, Claudia (ed.)

    2009-07-01

    Power generation by photovoltaic systems and buildings is much more than just an alternative to traditional electric power generation. As the planning and design of photovoltaics is increasingly shifting to the forefront, it is rapidly becoming a new challenge for architecture. This book describes the whole spectrum of possible applications - from inspiration to detail - of photovoltaics as an integral part of building envelopes and introduces groundbreaking examples and visions for the future, in which photovoltaic elements work as a successful part of exterior facades - combined with highly luminous and economical illuminated wallpaper and curtains inside buildings. Its range extends from early designs by artists such as Daniel Hausig to aspects of material selection to detail drawings of implemented solutions. The enormous variety of possible applications of this new (building) material demonstrates the huge potential it possesses. (orig.)

  8. Photovoltaic sources modeling and emulation

    CERN Document Server

    Piazza, Maria Carmela Di

    2012-01-01

    This book offers an extensive introduction to the modeling of photovoltaic generators and their emulation by means of power electronic converters will aid in understanding and improving design and setup of new PV plants.

  9. Penetration of Photovoltaics in Greece

    Directory of Open Access Journals (Sweden)

    Eugenia Giannini

    2015-06-01

    Full Text Available Recently, an interesting experiment was completed in Greece concerning photovoltaic penetration into the electricity production sector. Based on the relevant laws and in accordance to the related European directives, an explosive penetration process was completed in less than three years, resulting in a 7% share of photovoltaics in electricity production instead of the previous negligible share. The legislation was based on licensing simplification and generous feed-in-tariffs. This approach transformed photovoltaic technology from a prohibitively expensive to a competitive one. This work aims to summarize the relevant legislation and illustrate its effect on the resulting penetration. A sigmoid-shape penetration was observed which was explained by a pulse-type driving force. The return on investment indicator was proposed as an appropriate driving force, which incorporates feed-in-tariffs and turnkey-cost. Furthermore, the resulting surcharge on the electricity price due to photovoltaic penetration was also analyzed.

  10. Effect of Cross-Linking on the Performances of Starch-Based Biopolymer as Gel Electrolyte for Dye-Sensitized Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Pavithra Nagaraj

    2017-12-01

    Full Text Available Dye-sensitized solar cells (DSSCs have become a validated and economically credible competitor to the traditional solid-state junction photovoltaic devices. DSSCs based on biopolymer gel electrolyte systems offer the perspective of competitive conversion efficiencies with a very low-cost fabrication. In this paper, a new starch-based biopolymer gel electrolyte system is prepared by mixing lithium iodide and iodine with bare and citric acid cross-linked potato starches with glycerol as the plasticizing agent. The effect of the preparation methods on the starch cross-linking degree as well as the photoconversion efficiency of the resulting DSSC cells is carefully analyzed. Fourier transform spectroscopy, X-ray diffraction, and scanning electron microscopy were used to characterize the morphology and conformational changes of starch in the electrolytes. The conductivity of the biopolymer electrolytes was determined by electrochemical impedance spectroscopy. DSSC based on the starch-gel polymer electrolytes were characterized by photovoltaic measurements and electrochemical impedance spectroscopy. Results clearly show that the cross-linking increases the recombination resistance and open circuit voltage (VOC of the DSSC, and thereby the photoconversion efficiency of the cell. In particular, electrolytes containing 1.4 g bare and cross-linked starches showed ionic conductivities of σ = 1.61, 0.59, 0.38, and 0.35 S cm−1, and the corresponding DSSCs showed efficiencies of 1.2, 1.4, 0.93, and 1.11%, respectively.

  11. GaAs photovoltaics and optoelectronics using releasable multilayer epitaxial assemblies.

    Science.gov (United States)

    Yoon, Jongseung; Jo, Sungjin; Chun, Ik Su; Jung, Inhwa; Kim, Hoon-Sik; Meitl, Matthew; Menard, Etienne; Li, Xiuling; Coleman, James J; Paik, Ungyu; Rogers, John A

    2010-05-20

    Compound semiconductors like gallium arsenide (GaAs) provide advantages over silicon for many applications, owing to their direct bandgaps and high electron mobilities. Examples range from efficient photovoltaic devices to radio-frequency electronics and most forms of optoelectronics. However, growing large, high quality wafers of these materials, and intimately integrating them on silicon or amorphous substrates (such as glass or plastic) is expensive, which restricts their use. Here we describe materials and fabrication concepts that address many of these challenges, through the use of films of GaAs or AlGaAs grown in thick, multilayer epitaxial assemblies, then separated from each other and distributed on foreign substrates by printing. This method yields large quantities of high quality semiconductor material capable of device integration in large area formats, in a manner that also allows the wafer to be reused for additional growths. We demonstrate some capabilities of this approach with three different applications: GaAs-based metal semiconductor field effect transistors and logic gates on plates of glass, near-infrared imaging devices on wafers of silicon, and photovoltaic modules on sheets of plastic. These results illustrate the implementation of compound semiconductors such as GaAs in applications whose cost structures, formats, area coverages or modes of use are incompatible with conventional growth or integration strategies.

  12. The photovoltaic energy in Japan

    International Nuclear Information System (INIS)

    Georgel, O.

    2005-07-01

    Today the Japan is the leader of the photovoltaic energy. The first reason of this success is an action of the government integrating subventions for the installation of photovoltaic systems and a support of the scientific research. To explain this success, the author presents the energy situation in Japan, details the national programs, the industrial sector (market, silicon needs, recycling, manufacturers, building industry) and presents the main actors. (A.L.B.)

  13. Photovoltaic sub-cell interconnects

    Energy Technology Data Exchange (ETDEWEB)

    van Hest, Marinus Franciscus Antonius Maria; Swinger Platt, Heather Anne

    2017-05-09

    Photovoltaic sub-cell interconnect systems and methods are provided. In one embodiment, a photovoltaic device comprises a thin film stack of layers deposited upon a substrate, wherein the thin film stack layers are subdivided into a plurality of sub-cells interconnected in series by a plurality of electrical interconnection structures; and wherein the plurality of electrical interconnection structures each comprise no more than two scribes that penetrate into the thin film stack layers.

  14. Penetration of Photovoltaics in Greece

    OpenAIRE

    Eugenia Giannini; Antonia Moropoulou; Zacharias Maroulis; Glykeria Siouti

    2015-01-01

    Recently, an interesting experiment was completed in Greece concerning photovoltaic penetration into the electricity production sector. Based on the relevant laws and in accordance to the related European directives, an explosive penetration process was completed in less than three years, resulting in a 7% share of photovoltaics in electricity production instead of the previous negligible share. The legislation was based on licensing simplification and generous feed-in-tariffs. This approach ...

  15. Natural Flow Air Cooled Photovoltaics

    Science.gov (United States)

    Tanagnostopoulos, Y.; Themelis, P.

    2010-01-01

    Our experimental study aims to investigate the improvement in the electrical performance of a photovoltaic installation on buildings through cooling of the photovoltaic panels with natural air flow. Our experimental study aims to investigate the improvement in the electrical performance of a photovoltaic installation on buildings through cooling of the photovoltaic panels with natural air flow. We performed experiments using a prototype based on three silicon photovoltaic modules placed in series to simulate a typical sloping building roof with photovoltaic installation. In this system the air flows through a channel on the rear side of PV panels. The potential for increasing the heat exchange from the photovoltaic panel to the circulating air by the addition of a thin metal sheet (TMS) in the middle of air channel or metal fins (FIN) along the air duct was examined. The operation of the device was studied with the air duct closed tightly to avoid air circulation (CLOSED) and the air duct open (REF), with the thin metal sheet (TMS) and with metal fins (FIN). In each case the experiments were performed under sunlight and the operating parameters of the experimental device determining the electrical and thermal performance of the system were observed and recorded during a whole day and for several days. We collected the data and form PV panels from the comparative diagrams of the experimental results regarding the temperature of solar cells, the electrical efficiency of the installation, the temperature of the back wall of the air duct and the temperature difference in the entrance and exit of the air duct. The comparative results from the measurements determine the improvement in electrical performance of the photovoltaic cells because of the reduction of their temperature, which is achieved by the naturally circulating air.

  16. Advances in Photovoltaics at NREL

    Energy Technology Data Exchange (ETDEWEB)

    von Roedern, B.

    1999-09-09

    This paper discusses the critical strategic research and development issues in the development of next-generation photovoltaic technologies, emphasizing thin-film technologies that are believed to ultimately lead to lower production costs. The critical research and development issues for each technology are identified. An attempt is made to identify the strengths and weaknesses of the different technologies, and to identify opportunities for fundamental research activities suited to advance the introduction of improved photovoltaic modules.

  17. How Solid-Electrolyte Interphase Forms in Aqueous Electrolytes.

    Science.gov (United States)

    Suo, Liumin; Oh, Dahyun; Lin, Yuxiao; Zhuo, Zengqing; Borodin, Oleg; Gao, Tao; Wang, Fei; Kushima, Akihiro; Wang, Ziqiang; Kim, Ho-Cheol; Qi, Yue; Yang, Wanli; Pan, Feng; Li, Ju; Xu, Kang; Wang, Chunsheng

    2017-12-27

    Solid-electrolyte interphase (SEI) is the key component that enables all advanced electrochemical devices, the best representative of which is Li-ion battery (LIB). It kinetically stabilizes electrolytes at potentials far beyond their thermodynamic stability limits, so that cell reactions could proceed reversibly. Its ad hoc chemistry and formation mechanism has been a topic under intensive investigation since the first commercialization of LIB 25 years ago. Traditionally SEI can only be formed in nonaqueous electrolytes. However, recent efforts successfully transplanted this concept into aqueous media, leading to significant expansion in the electrochemical stability window of aqueous electrolytes from 1.23 V to beyond 4.0 V. This not only made it possible to construct a series of high voltage/energy density aqueous LIBs with unprecedented safety, but also brought high flexibility and even "open configurations" that have been hitherto unavailable for any LIB chemistries. While this new class of aqueous electrolytes has been successfully demonstrated to support diversified battery chemistries, the chemistry and formation mechanism of the key component, an aqueous SEI, has remained virtually unknown. In this work, combining various spectroscopic, electrochemical and computational techniques, we rigorously examined this new interphase, and comprehensively characterized its chemical composition, microstructure and stability in battery environment. A dynamic picture obtained reveals how a dense and protective interphase forms on anode surface under competitive decompositions of salt anion, dissolved ambient gases and water molecule. By establishing basic laws governing the successful formation of an aqueous SEI, the in-depth understanding presented in this work will assist the efforts in tailor-designing better interphases that enable more energetic chemistries operating farther away from equilibria in aqueous media.

  18. Recent results on aqueous electrolyte cells

    KAUST Repository

    Wessells, Colin; Huggins, Robert A.; Cui, Yi

    2011-01-01

    The improved safety of aqueous electrolytes makes aqueous lithium-ion batteries an attractive alternative to commercial cells utilizing flammable and expensive organic electrolytes. Two important issues relating to their use have been addressed

  19. Graded Recombination Layers for Multijunction Photovoltaics

    KAUST Repository

    Koleilat, Ghada I.

    2012-06-13

    Multijunction devices consist of a stack of semiconductor junctions having bandgaps tuned across a broad spectrum. In solar cells this concept is used to increase the efficiency of photovoltaic harvesting, while light emitters and detectors use it to achieve multicolor and spectrally tunable behavior. In series-connected current-matched multijunction devices, 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 recently reported a tandem solar cell in which the recombination layer was implemented using a progression of n-type oxides whose doping densities and work functions serve to connect, with negligible resistive loss at solar current densities, the constituent cells. Here we present the generalized conditions for design of efficient graded recombination layer solar devices. We report the number of interlayers and the requirements on work function and doping of each interlayer, to bridge an work function difference as high as 1.6 eV. We also find solutions that minimize the doping required of the interlayers in order to minimize optical absorption due to free carriers in the graded recombination layer (GRL). We demonstrate a family of new GRL designs experimentally and highlight the benefits of the progression of dopings and work functions in the interlayers. © 2012 American Chemical Society.

  20. Architectures and criteria for the design of high efficiency organic photovoltaic cells

    Science.gov (United States)

    Rand, Barry; Forrest, Stephen R; Pendergrast Burk, Diane

    2015-03-31

    A method for fabricating an organic photovoltaic cell includes providing a first electrode; depositing a series of at least seven layers onto the first electrode, each layer consisting essentially of a different organic semiconductor material, the organic semiconductor material of at least an intermediate layer of the sequence being a photoconductive material; and depositing a second electrode onto the sequence of at least seven layers. One of the first electrode and the second electrode is an anode and the other is a cathode. The organic semiconductor materials of the series of at least seven layers are arranged to provide a sequence of decreasing lowest unoccupied molecular orbitals (LUMOs) and a sequence of decreasing highest occupied molecular orbitals (HOMOs) across the series from the anode to the cathode.