WorldWideScience

Sample records for partial cds genbank

  1. GenBank blastx search result: AK060423 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060423 001-010-H01 AY498612.1 Rhodococcus opacus putative GntR type regulator of taurine... degradation (tauR) gene, partial cds; and alanine dehydrogenase (ald) and taurine-pyruvate aminotransferase (tpa) genes, complete cds.|BCT BCT 7e-32 +3 ...

  2. GenBank blastx search result: AK062096 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062096 001-044-H12 M86348.1 Pseudomonas sp. LB400 biphenyl dioxygenase (bphA), biphenyl dioxygenase (bph...E), biphenyl dioxygenase (bphF) and biphenyl dioxygenase (bphG)s, complete cds, and dihydrodiol dehydrogenase (bphB), partial cds.|BCT BCT 1e-14 +3 ...

  3. GenBank blastx search result: AK062096 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062096 001-044-H12 U17130.1 Rhodococcus erythropolis ORF6' gene, partial cds, regulatory protein ThcR (thc...R), cytochrome P-450 (thcB), ORF4, rhodocoxin (thcC), rhodocoxin reductase (thcD) and ORF5 genes, complete cds.|BCT BCT 3e-18 +3 ...

  4. GenBank blastx search result: AK104229 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104229 006-307-D03 AF023268.1 Homo sapiens clk2 kinase (CLK2), propin1, cote1, glucocerebro...sidase (GBA), and metaxin genes, complete cds; metaxin pseudogene and glucocerebrosidase pseudogene; and thrombospondin3 (THBS3) gene, partial cds.|PRI PRI 3e-41 +3 ...

  5. GenBank blastx search result: AK058642 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058642 001-018-E05 AF023268.1 Homo sapiens clk2 kinase (CLK2), propin1, cote1, glucocerebro...sidase (GBA), and metaxin genes, complete cds; metaxin pseudogene and glucocerebrosidase pseudogene; and thrombospondin3 (THBS3) gene, partial cds.|PRI PRI 2e-18 +3 ...

  6. GenBank blastx search result: AK061708 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061708 001-037-F11 AF023268.1 Homo sapiens clk2 kinase (CLK2), propin1, cote1, glucocerebro...sidase (GBA), and metaxin genes, complete cds; metaxin pseudogene and glucocerebrosidase pseudogene; and thrombospondin3 (THBS3) gene, partial cds.|PRI PRI 1e-41 +3 ...

  7. GenBank blastx search result: AK287540 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287540 J065011K01 AF013216.1 AF013216 Myxococcus xanthus Dog (dog), isocitrate lyase (icl), Mls (mls), Ufo... (ufo), fumarate hydratase (fhy), and proteosome major subunit (clpP) genes, complete cds; and acyl-CoA oxidase (aco) gene, partial cds. BCT 0.0 0 ...

  8. GenBank blastx search result: AK243510 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243510 J100075B22 AF013216.1 AF013216 Myxococcus xanthus Dog (dog), isocitrate lyase (icl), Mls (mls), Ufo... (ufo), fumarate hydratase (fhy), and proteosome major subunit (clpP) genes, complete cds; and acyl-CoA oxidase (aco) gene, partial cds. BCT 2e-87 1 ...

  9. GenBank blastx search result: AK243527 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243527 J100075P16 AF013216.1 AF013216 Myxococcus xanthus Dog (dog), isocitrate lyase (icl), Mls (mls), Ufo... (ufo), fumarate hydratase (fhy), and proteosome major subunit (clpP) genes, complete cds; and acyl-CoA oxidase (aco) gene, partial cds. BCT 1e-143 1 ...

  10. GenBank blastx search result: AK241214 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241214 J065122P06 AF013216.1 AF013216 Myxococcus xanthus Dog (dog), isocitrate lyase (icl), Mls (mls), Ufo... (ufo), fumarate hydratase (fhy), and proteosome major subunit (clpP) genes, complete cds; and acyl-CoA oxidase (aco) gene, partial cds. BCT 1e-151 1 ...

  11. GenBank blastn search result: AK241214 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241214 J065122P06 AF013216.1 AF013216 Myxococcus xanthus Dog (dog), isocitrate lyase (icl), Mls (mls), Ufo... (ufo), fumarate hydratase (fhy), and proteosome major subunit (clpP) genes, complete cds; and acyl-CoA oxidase (aco) gene, partial cds. BCT 8e-18 1 -1 ...

  12. GenBank blastx search result: AK287639 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287639 J065078H11 AF287967.1 AF287967 Homo sapiens homeobox B7 (HOXB7) gene, partial cds; and home...obox B6 (HOXB6), homeobox B5 (HOXB5), homeobox B4 (HOXB4), and homeobox B3 (HOXB3) genes, complete cds. PRI 0.0 0 ...

  13. GenBank

    OpenAIRE

    Benson, Dennis A.; Karsch-Mizrachi, Ilene; Lipman, David J.; Ostell, James; Rapp, Barbara A.; Wheeler, David L.

    2002-01-01

    The GenBank sequence database incorporates publicly available DNA sequences of more than 105 000 different organisms, primarily through direct submission of sequence data from individual laboratories and large-scale sequencing projects. Most submissions are made using the BankIt (web) or Sequin programs and accession numbers are assigned by GenBank staff upon receipt. Data exchange with the EMBL Data Library and the DNA Data Bank of Japan helps ensure comprehensive worldwide coverage. GenBank...

  14. GenBank

    Data.gov (United States)

    U.S. Department of Health & Human Services — GenBank is the NIH genetic sequence database, an annotated collection of all publicly available DNA sequences. GenBank is designed to provide and encourage access...

  15. Homo sapiens natriuretic peptide precursor type C (NPPC) mRNA,partial cds and 3' UTR.

    OpenAIRE

    Landi, Stefano; Melaiu, Ombretta; Cabiati, Manuela; Landi, Debora; Caselli, Chiara; Prescimone, Tommaso; Giannessi, Daniela; Gemignani, Federica; Del Ry, Silvia

    2010-01-01

    LOCUS HQ419060 318 bp mRNA linear PRI 24-NOV-2010 DEFINITION Homo sapiens natriuretic peptide precursor type C (NPPC) mRNA, partial cds and 3' UTR. ACCESSION HQ419060 VERSION HQ419060.1 GI:312261407 KEYWORDS . SOURCE Homo sapiens (human) ORGANISM Homo sapiens Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo. REFERENCE 1 (bases 1 to 318) AUTHORS Landi,S., Melaiu,O., Cabiati,M., Landi,D., C...

  16. GenBank blastx search result: AK062185 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062185 001-046-E03 AF080002.1 Heliobacillus mobilis exopolyphosphatase Ppx (ppx) gene, partial cds; cobyric acid synthase CobQ (cobQ), UDP-N-acetylmuramyl tripeptide synthetase MurC (murC),

  17. GenBank blastx search result: AK243269 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243269 J100049H19 L41732.4 ABCLSDA Gluconacetobacter diazotrophicus levansucrase precursor (lsd...A), levanase precursor (lsdB), pseudopilin G precursor (lsdG), prepilin peptidase and N-methyl...transferase O (gspO), kinase E (lsdE), LsdF (lsdF), pseudopilin H precursor (lsdH), pseudopilin I precursor (lsd...I), pseudopilin J precursor (lsdJ), LsdL (lsdL), LsdM (lsdM), and LsdN (lsdN)... genes, complete cds; secretin D (lsdD) gene, partial cds; and unknown gene. BCT 6e-26 1 ...

  18. GenBank blastx search result: AK058591 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058591 001-017-G08 AY953023.1 Rattus norvegicus smooth muscle myosin heavy chain, alternative... isoform B, S1 region mRNA, partial cds, alternatively spliced.|ROD ROD 4e-66 +2 ...

  19. GenBank

    OpenAIRE

    Benson, Dennis A.; Cavanaugh, Mark; Clark, Karen; Karsch-Mizrachi, Ilene; Lipman, David J.; Ostell, James; Sayers, Eric W.

    2012-01-01

    GenBank? (http://www.ncbi.nlm.nih.gov) is a comprehensive database that contains publicly available nucleotide sequences for almost 260 000 formally described species. These sequences are obtained primarily through submissions from individual laboratories and batch submissions from large-scale sequencing projects, including whole-genome shotgun (WGS) and environmental sampling projects. Most submissions are made using the web-based BankIt or standalone Sequin programs, and GenBank staff assig...

  20. GenBank blastx search result: AK059350 [KOME

    Lifescience Database Archive (English)

    Full Text Available r SLU7; DNA segment, Chr 11, ERATO Doi 730, expressed; DNA segment, Chr 3, Brigham & Womens Genetics 0878 expressed, mRNA (cDNA clone IMAGE:6890616), partial cds.|ROD ROD 1e-103 +3 ...

  1. GenBank blastx search result: AK107397 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK107397 002-127-D06 AB052295.1 Brevibacterium fuscum var. dextranlyticum genes for... ABC membrane transporter homologues, putative alpha-glucosidase, isomaltotrio-dextranase precursor, partial and complete cds.|BCT BCT 1e-122 +2 ...

  2. GenBank

    OpenAIRE

    Benson, Dennis A.; Karsch-Mizrachi, Ilene; Lipman, David J.; Ostell, James; Sayers, Eric W.

    2008-01-01

    GenBank? is a comprehensive database that contains publicly available nucleotide sequences for more than 300 000 organisms named at the genus level or lower, obtained primarily through submissions from individual laboratories and batch submissions from large-scale sequencing projects. Most submissions are made using the web-based BankIt or standalone Sequin programs, and accession numbers are assigned by GenBank? staff upon receipt. Daily data exchange with the European Molecular Biology Labo...

  3. GenBank blastn search result: AK289245 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289245 J100077H08 AY525350.1 AY525350 Castanea ozarkensis voucher CC R-etaT3, G. Miller (Connecticut Agric...ultural Experiment Station, New Haven, Connecticut) Ycf9 (ycf9) gene, partial cds;

  4. GenBank

    OpenAIRE

    Benson, Dennis A.; Karsch-Mizrachi, Ilene; Lipman, David J.; Ostell, James; Wheeler, David L.

    2006-01-01

    GenBank (R) is a comprehensive database that contains publicly available nucleotide sequences for more than 240 000 named organisms, obtained primarily through submissions from individual laboratories and batch submissions from large-scale sequencing projects. Most submissions are made using the web-based BankIt or standalone Sequin programs and accession numbers are assigned by GenBank staff upon receipt. Daily data exchange with the EMBL Data Library in Europe and the DNA Data Bank of Japan...

  5. GenBank blastx search result: AK104368 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104368 001-035-E04 U35248.2 Streptococcus salivarius urea transporter (ureI) gene, partial cds; urease... beta subunit (ureA), urease gamma subunit (ureB), urease alpha subunit (ureC), urease ...accessory protein (ureE), urease accessory protein (ureF), urease accessory protein (ureG), urease accessory

  6. GenBank blastx search result: AK061794 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061794 001-039-F11 AF031161.1 Pseudomonas sp. VLB120 styrene degradation genes in...cluding histidine kinase (stdSc) gene, partial cds; and transcriptional activator (stdR), styrene monooxygen...ase large component (stdA), styrene monooxygenase small component (stdB), styrene oxide isomerase (stdC), an

  7. Cholecystokinin (CCK) functional cholescintigraphic findings in patients with a partial cystic duct obstruction - the cystic duct syndrome (CDS)

    International Nuclear Information System (INIS)

    Fink-Bennett, D.; DeRidder, P.; Kolozsi, W.; Gordon, R.

    1984-01-01

    Fourteen patients (pts.) with a CDS underwent CCK functional cholescintigraphy (FC). All pts. presented with persistent post-prandial right upper quadrant pain and biliary colic. None had an abnormal OCG, gallbladder (GB) ultrasound exam or upper G.I. series. All had macro- or microscopically abnormal cystic ducts (5 fibrotic, 7 elongated and narrow, 2 kinked) with (12) or without (2) concomitant chronic cholecystitis. Each pt. (NPO after 12 A.M.) received 5 mCi of technetium (TC)-99m Hepatolite. When the GB max. filled, .02 ug/kg CCK was administered (3 min.) I.V. Background corrected GBEFs were determined q.5 min. x 4 by ratioing the pre-CCK GB cts. minus post-CCK GB cts. to pre-CCK GB cts. GB EFRs were: 3 (12%), 2 (17%), and 1 each 0%, 1.3%, 3%, 4%, 6%, 11%, 14%, 18.5% and 22%. No pt. with a partially occluded cystic duct with or without concomitant chronic cholecystitis had an ejection fraction that exceeded 22%. In an appropriate clinical setting, a low ejection fraction response to CCK should alert the physician to the presence of either chronic acalculous cholecystitis, CDS, or the combination of both

  8. Arabidopsis CDS blastp result: AK068433 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK068433 J013156D16 At1g20620.2 catalase 3 (SEN2) almost identical to catalase 3 SP...:Q42547, GI:3123188 from [Arabidopsis thaliana]; identical to catalase 3 (SEN2) mRNA, partial cds GI:3158369 1e-63 ...

  9. Cloning and sequence analysis of a partial CDS of leptospiral ligA gene in pET-32a - Escherichia coli DH5α system

    Directory of Open Access Journals (Sweden)

    Manju Soman

    2018-04-01

    Full Text Available Aim: This study aims at cloning, sequencing, and phylogenetic analysis of a partial CDS of ligA gene in pET-32a - Escherichia coli DH5α system, with the objective of identifying the conserved nature of the ligA gene in the genus Leptospira. Materials and Methods: A partial CDS (nucleotide 1873 to nucleotide 3363 of the ligA gene was amplified from genomic DNA of Leptospira interrogans serovar Canicola by polymerase chain reaction (PCR. The PCR-amplified DNA was cloned into pET-32a vector and transformed into competent E. coli DH5α bacterial cells. The partial ligA gene insert was sequenced and the nucleotide sequences obtained were aligned with the published ligA gene sequences of other Leptospira serovars, using nucleotide BLAST, NCBI. Phylogenetic analysis of the gene sequence was done by maximum likelihood method using Mega 6.06 software. Results: The PCR could amplify the 1491 nucleotide sequence spanning from nucleotide 1873 to nucleotide 3363 of the ligA gene and the partial ligA gene could be successfully cloned in E. coli DH5α cells. The nucleotide sequence when analyzed for homology with the reported gene sequences of other Leptospira serovars was found to have 100% homology to the 1910 bp to 3320 bp sequence of ligA gene of L. interrogans strain Kito serogroup Canicola. The predicted protein consisted of 470 aminoacids. Phylogenetic analysis revealed that the ligA gene was conserved in L. interrogans species. Conclusion: The partial ligA gene could be successfully cloned and sequenced from E. coli DH5α cells. The sequence showed 100% homology to the published ligA gene sequences. The phylogenetic analysis revealed the conserved nature of the ligA gene. Further studies on the expression and immunogenicity of the partial LigA protein need to be carried out to determine its competence as a subunit vaccine candidate.

  10. GenBank.

    OpenAIRE

    Benson, D; Lipman, D J; Ostell, J

    1993-01-01

    The GenBank sequence database has undergone an expansion in data coverage, annotation content and the development of new services for the scientific community. In addition to nucleotide sequences, data from the major protein sequence and structural databases, and from U.S. and European patents is now included in an integrated system. MEDLINE abstracts from published articles describing the sequences provide an important new source of biological annotation for sequence entries. In addition to ...

  11. CERN Document Server (CDS): Introduction

    CERN Multimedia

    CERN. Geneva; Costa, Flavio

    2017-01-01

    A short online tutorial introducing the CERN Document Server (CDS). Basic functionality description, the notion of Revisions and the CDS test environment. Links: CDS Production environment CDS Test environment  

  12. Preserving Accuracy in GenBank

    DEFF Research Database (Denmark)

    Bidartondo, M.I.; Bruns, T. D.; Blackwell, M.

    2008-01-01

    GenBank, the public repository for nucleotide and protein sequences, is a critical resource for molecular biology, evolutionary biology, and ecology. While some attention has been drawn to sequence errors (1), common annotation errors also reduce the value of this database. In fact, for organisms...

  13. TiO2-CdS Nanocomposites: Effect of CdS Oxidation on the Photocatalytic Activity

    Directory of Open Access Journals (Sweden)

    A. Hamdi

    2016-01-01

    Full Text Available Nanocomposites TiO2-CdS with different relative contents of CdS (molar ratios Cd/Ti = 0.02, 0.03, 0.05, 0.1, 0.2, and 0.5 were studied. The structural, photophysical, and chemical properties were investigated using XRD, Raman spectroscopy, XPS, GSDR, and LIL. XRD and Raman results confirmed the presence of TiO2 and CdS with intensities dependent on the ratio Cd/Ti. The presence of CdSO4 was detected by XPS at the surface of all TiO2-CdS composites. The relative amount of sulphate was dependent on the CdS loading. Luminescence time-resolved spectra clearly proved the existence of an excitation transfer process from CdS to TiO2 through the luminescence emission from TiO2 after excitation of CdS at λexc=410 nm, where no direct excitation of TiO2 occurs. Photodegradation of a series of aromatic carboxylic acids—benzoic, salicylic, 4-bromobenzoic, 3-phenylpropionic, and veratric acids—showed a great enhancement in the photocatalytic efficiency of the TiO2-CdS composites, which is due, mainly, to the effect of the charge carriers’ increased lifetime. In addition, it was shown that the oxidation of CdS to CdSO4 did not result in the deactivation of the photocatalytic properties and even contributed to enhance the degradation efficiency.

  14. C. pneumoniae CdsL regulates CdsN ATPase activity, and disruption with a peptide mimetic prevents bacterial invasion

    Directory of Open Access Journals (Sweden)

    Chris Blair Stone

    2011-02-01

    Full Text Available Chlamydiae are obligate intracellular pathogens that likely require type III secretion (T3S to invade cells and replicate intracellulary within a cytoplasmic vacuole called an inclusion body. C. pneumoniae possess a YscL ortholog, CdsL, that has been shown to interact with the T3S ATPase (CdsN. In this report we demonstrate that CdsL down-regulates CdsN enzymatic activity in a dose-dependent manner. Using PepScan epitope mapping we identified two separate binding domains to which CdsL binds viz. CdsN 221-229 and CdsN265-270. We confirmed the binding domains using a pull-down assay and showed that GST-CdsN221-270, which encompasses these peptides, co-purified with His-CdsL. Next, we used orthology modeling based on the crystal structure of a T3S ATPase ortholog from E. coli, EscN, to map the binding domains on the predicted three dimensional structure of CdsN. The CdsL binding domains mapped to the catalytic domain of the ATPase, one in the central channel of the ATPase hexamer and one on the outer face. Since peptide mimetics have been used to disrupt essential protein interactions of the chlamydial T3S system and inhibit T3S-mediated invasion of HeLa cells, we hypothesized that if CdsL – CdsN binding is essential for regulating T3S then a CdsN peptide mimetic could be used to potentially block T3S and Chlamydial invasion. Treatment of EBs with a CdsN peptide mimetic inhibited C. pneumoniae invasion into HeLa cells in a dose-dependent fashion. This report represents the first use of Pepscan technology to identify binding domains for specific T3S proteins viz. CdsL on the ATPase, CdsN, and demonstrates that peptide mimetics can be used as anti-virulence factors to block bacterial invasion.

  15. GenBank blastx search result: AK242295 [KOME

    Lifescience Database Archive (English)

    Full Text Available e cds; transposons Ophelia2, Angela3s, and XJ3, complete sequence; LRR protein WM1.3 (WM1.3) gene, complete cds; Stowaway... MITE, transposons XJ1, Jody, Angela, and XJ and Stowaway MITE, comp

  16. GenBank blastx search result: AK241352 [KOME

    Lifescience Database Archive (English)

    Full Text Available e cds; transposons Ophelia2, Angela3s, and XJ3, complete sequence; LRR protein WM1.3 (WM1.3) gene, complete cds; Stowaway... MITE, transposons XJ1, Jody, Angela, and XJ and Stowaway MITE, comp

  17. GenBank blastn search result: AK241152 [KOME

    Lifescience Database Archive (English)

    Full Text Available e cds; transposons Ophelia2, Angela3s, and XJ3, complete sequence; LRR protein WM1.3 (WM1.3) gene, complete cds; Stowaway... MITE, transposons XJ1, Jody, Angela, and XJ and Stowaway MITE, comp

  18. GenBank blastx search result: AK241749 [KOME

    Lifescience Database Archive (English)

    Full Text Available e cds; transposons Ophelia2, Angela3s, and XJ3, complete sequence; LRR protein WM1.3 (WM1.3) gene, complete cds; Stowaway... MITE, transposons XJ1, Jody, Angela, and XJ and Stowaway MITE, comp

  19. GenBank blastx search result: AK241418 [KOME

    Lifescience Database Archive (English)

    Full Text Available e cds; transposons Ophelia2, Angela3s, and XJ3, complete sequence; LRR protein WM1.3 (WM1.3) gene, complete cds; Stowaway... MITE, transposons XJ1, Jody, Angela, and XJ and Stowaway MITE, comp

  20. GenBank blastx search result: AK241200 [KOME

    Lifescience Database Archive (English)

    Full Text Available e cds; transposons Ophelia2, Angela3s, and XJ3, complete sequence; LRR protein WM1.3 (WM1.3) gene, complete cds; Stowaway... MITE, transposons XJ1, Jody, Angela, and XJ and Stowaway MITE, comp

  1. GenBank blastx search result: AK240882 [KOME

    Lifescience Database Archive (English)

    Full Text Available e cds; transposons Ophelia2, Angela3s, and XJ3, complete sequence; LRR protein WM1.3 (WM1.3) gene, complete cds; Stowaway... MITE, transposons XJ1, Jody, Angela, and XJ and Stowaway MITE, comp

  2. A comparative study on CdS: PEO and CdS: PMMA nanocomposite solid films

    Energy Technology Data Exchange (ETDEWEB)

    Padmaja, S. [Thin film centre, PSG College of Technology, Coimbatore (India); Jayakumar, S., E-mail: s_jayakumar_99@yahoo.com [Department of Physics, PSG Institute of Technology and Applied Research, Coimbatore (India); Balaji, R.; Vaideki, K. [Thin film centre, PSG College of Technology, Coimbatore (India)

    2016-08-15

    Cadmium Sulphide (CdS) nanoparticles were reinforced in Poly(ethylene Oxide) (PEO) and Poly(methyl methacrylate) (PMMA) matrices by in situ technique. The presence of CdS in PEO and PMMA matrix was confirmed using X-ray photoelectron spectroscopy (XPS). Fourier Transform Infrared spectroscopy (FTIR) analysis disclosed the co-ordination of CdS in the matrices. Thermal analysis of the nanocomposites was carried out using Differential Scanning calorimetric studies (DSC). The optical studies using UV–vis spectroscopy were carried out to find the band gap of the materials and the absorption onset. The CdS particle size in the matrices was found by Effective Mass Approximation (EMA) model using the band gap values and was confirmed by TEM studies. The surface trapped emissions of the nanocomposites were observed from the photoluminescence (PL) spectra. The distribution of CdS particles in the polymer matrices were presented by Atomic force microscopic studies (AFM).

  3. A comparative study on CdS: PEO and CdS: PMMA nanocomposite solid films

    International Nuclear Information System (INIS)

    Padmaja, S.; Jayakumar, S.; Balaji, R.; Vaideki, K.

    2016-01-01

    Cadmium Sulphide (CdS) nanoparticles were reinforced in Poly(ethylene Oxide) (PEO) and Poly(methyl methacrylate) (PMMA) matrices by in situ technique. The presence of CdS in PEO and PMMA matrix was confirmed using X-ray photoelectron spectroscopy (XPS). Fourier Transform Infrared spectroscopy (FTIR) analysis disclosed the co-ordination of CdS in the matrices. Thermal analysis of the nanocomposites was carried out using Differential Scanning calorimetric studies (DSC). The optical studies using UV–vis spectroscopy were carried out to find the band gap of the materials and the absorption onset. The CdS particle size in the matrices was found by Effective Mass Approximation (EMA) model using the band gap values and was confirmed by TEM studies. The surface trapped emissions of the nanocomposites were observed from the photoluminescence (PL) spectra. The distribution of CdS particles in the polymer matrices were presented by Atomic force microscopic studies (AFM).

  4. GenBank blastx search result: AK104368 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104368 001-035-E04 L03308.1 E.coli urease gene cluster: urease accessory protein F (UreF), 3' end cds; ure...ase accessory protein G (UreG) gene, complete cds.|BCT BCT 2e-56 +1 ...

  5. GenBank blastn search result: AK064582 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK064582 002-112-F03 AY007820.1 Daucus carota ATPase8 (ATP8) gene, ATP8-Sp1b allele, complete cds; chimeric... ATPase9 (ATP9) gene, ATP9-Sp3 allele, complete cds; and chimeric ATPase6 (ATP6) gen

  6. Safe-haven CDS Premia

    DEFF Research Database (Denmark)

    Klingler, Sven; Lando, David

    We argue that Credit Default Swap (CDS) premia for safe-haven sovereigns, like Germany and the United States, are driven to a large extent by regulatory requirements under which derivatives dealing banks have an incentive to buy CDS to hedge counterparty credit risk of their counterparties. We...

  7. Clinical Decision Support (CDS) Inventory

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Clinical Decision Support (CDS) Inventory contains descriptions of past and present CDS projects across the Federal Government. It includes Federal projects,...

  8. Safe Haven CDS Premiums

    DEFF Research Database (Denmark)

    Klingler, Sven; Lando, David

    Credit Default Swaps can be used to lower capital requirements of dealer banks who enter into uncollateralized derivatives positions with sovereigns. We show in a model that the regulatory incentive to obtain capital relief makes CDS contracts valuable to dealer banks and empirically that...... support that CDS contracts are used for capital relief....

  9. Strasbourg Astronomical Data Center (CDS

    Directory of Open Access Journals (Sweden)

    F Genova

    2013-01-01

    Full Text Available The Centre de Donnees astronomiques de Strasbourg (CDS, created in 1972, has been a pioneer in the dissemination of digital scientific data. Ensuring sustainability for several decades has been a major issue because science and technology evolve continuously and the data flow increases endlessly. The paper briefly describes CDS activities, major services, and its R&D strategy to take advantage of new technologies. The next frontiers for CDS are the new Web 2.0/3.0 paradigm and, at a more general level, global interoperability of astronomical on-line resources in the Virtual Observatory framework.

  10. GeoBoost: accelerating research involving the geospatial metadata of virus GenBank records.

    Science.gov (United States)

    Tahsin, Tasnia; Weissenbacher, Davy; O'Connor, Karen; Magge, Arjun; Scotch, Matthew; Gonzalez-Hernandez, Graciela

    2018-05-01

    GeoBoost is a command-line software package developed to address sparse or incomplete metadata in GenBank sequence records that relate to the location of the infected host (LOIH) of viruses. Given a set of GenBank accession numbers corresponding to virus GenBank records, GeoBoost extracts, integrates and normalizes geographic information reflecting the LOIH of the viruses using integrated information from GenBank metadata and related full-text publications. In addition, to facilitate probabilistic geospatial modeling, GeoBoost assigns probability scores for each possible LOIH. Binaries and resources required for running GeoBoost are packed into a single zipped file and freely available for download at https://tinyurl.com/geoboost. A video tutorial is included to help users quickly and easily install and run the software. The software is implemented in Java 1.8, and supported on MS Windows and Linux platforms. gragon@upenn.edu. Supplementary data are available at Bioinformatics online.

  11. Mn2+ anchored CdS polymer nanocomposites: An efficient alternative for Mn2+ doped CdS nanoparticles

    International Nuclear Information System (INIS)

    Saikia, Bhaskar Jyoti; Nath, Bikash Chandra; Borah, Chandramika; Dolui, Swapan Kumar

    2015-01-01

    A chelating bi-functional polymer brushes was prepared via atom transfer radical polymerization using grafting-from methodology. Mn 2+ -anchored CdS-polymer nanocomposites were synthesized using this graft copolymer by simple chelation method resulting in emission at about 620 nm which originates from the fluorescence of manganese ions embedded on the surface of CdS nanoparticles. This method provides an efficient straightforward substitute of Mn 2+ dopped CdS nanoparticles. Optical properties of the composites were investigated which indicates that simple Mn 2+ chelation and subsequent binding of CdS in a polymer matrix can have similar effect in the luminescence property as those synthesized via complex doping methods. Moreover this methodology can be applied for synthesis of any metal anchored nanocomposites proficiently and cost effectively in large-scale production. - Highlights: • A chelating bifunctional copolymer brush was synthesized via ATRP. • CdS nanoparticles and Mn 2+ were coupled with the bifunctional polymer. • Composites showed emission properties similar to Mn 2+ doped CdS nanoparticles. • Side chain length of the polymers also affect the emission properties of the composites.

  12. Simple and green synthesis of protein-conjugated CdS nanoparticles and spectroscopic study on the interaction between CdS and zein

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Dezhi, E-mail: dezhiqin@163.com; Zhang, Li; Du, Xian; Wang, Yabo; Zhang, Qiuxia [Pingdingshan University, College of Chemistry and Environmental Engineering (China)

    2016-09-15

    The present study demonstrates the role of zein molecules in synthesizing CdS nanoassemblies through protein-directed, green synthetic approach. Zein molecules can as capping ligand and stabilizing agent to regulate the nucleation and growth of CdS nanocrystals, and the obtained products are organic–inorganic nanocomposites. The analysis of surface charge and conductivity indicates that strong electrostatic force restricts mobility of ions, which creates a local supersaturation surrounding the binding sites of zein and reduces the activated energy of nucleation. The interaction between Cd{sup 2+}/CdS and zein molecules was systematically investigated through spectroscopy techniques. Fourier transform infrared (FT-IR) spectra were used to envisage the binding of the functional groups of zein with the surface of CdS nanoparticles. Ultraviolet visible (UV–Vis) and photoluminescence (PL) spectra results show that Cd{sup 2+}/CdS might interact with the aromatic amino acids of protein molecules and change its chemical microenvironment. The quantum-confined effect of nanocrystals is confirmed by optical absorption spectrum due to the small size (3–5 nm) of CdS particles. The data of circular dichroism (CD) spectra indicate that the formation of CdS nanocrystals could lead to the conformational change of zein molecules. Moreover, the possible mechanism of CdS nanocrystals growth in zein solution was also discussed. The weak interactions such as Van der Waals, hydrophobic forces and hydrogen bonds in zein molecules should play a crucial factor in the self-assembly of small nanoparticles.

  13. What do we know about speculation in the CDS market?

    NARCIS (Netherlands)

    L. Norden (Lars); K. Radoeva (Kristina)

    2012-01-01

    textabstractWe measure speculation in the CDS market and investigate its determinants. The CDS volume on a firm that exceeds its outstanding debt (= naked CDS) indicates speculation since hedging can be ruled out. Using weekly CDS trading volume data for actively traded U.S. firms during 2008-2012,

  14. A configurable CDS for the production laboratory

    CERN Document Server

    Meek, Irish

    2003-01-01

    Various aspects of a configurable chromatography data system (CDS) for the production laboratory are discussed. The Atlas CDS can be configured extensively to fit the production laboratory work flow and meet the needs of analysts. The CDS can also be configured to automatically create a sample sequence with the required number of injections and download methods to the dedicated instrument. The Atlas Quick Start wizard offers uses quick way of generating a sequence from a predefined template and starting a run. (Edited abstract).

  15. Biosynthesis of CdS nanoparticles in banana peel extract.

    Science.gov (United States)

    Zhou, Guang Ju; Li, Shuo Hao; Zhang, Yu Cang; Fu, Yun Zhi

    2014-06-01

    Cadmium sulfide (CdS) nanoparticles (NPs) were synthesized by using banana peel extract as a convenient, non-toxic, eco-friendly 'green' capping agent. Cadmium nitrate and sodium sulfide are main reagents. A variety of CdS NPs are prepared through changing reaction conditions (banana extracts, the amount of banana peel extract, solution pH, concentration and reactive temperature). The prepared CdS colloid displays strong fluorescence spectrum. X-ray diffraction analysis demonstrates the successful formation of CdS NPs. Fourier transform infra-red (FTIR) spectrogram indicates the involvement of carboxyl, amine and hydroxyl groups in the formation of CdS NPs. Transmission electron microscope (TEM) result reveals that the average size of the NPs is around 1.48 nm.

  16. Technical training: CERN Document Server (CDS), Inspire and Library Services

    CERN Multimedia

    IT & GS Departments

    2012-01-01

    A new training course, “CERN Document Server (CDS), Inspire and Library Services”, is available since the beginning of the year. The training course is given by members of CERN’s CDS Team (IT-CIS group) and the Library Services (GIS SIS group) and is intended for all members of personnel of CERN. This course will present CDS and inspirehep.net and the content, scope and scientific information available in or with CDS, as much as the classification and organization of the documents. It is intended to give you the training needed to know how to use CDS most efficiently and in particular covers: the main characteristics and advanced features for the search of documents (scientific, multimedia, etc). the collaborative tools : baskets, alerts, comments, evaluation, etc. the submission of documents in CDS and examples of workflows. An important part of the training is composed of various exercises, designed to acquire practical ability to work with CDS in cases similar to re...

  17. Synthesis of CdS nanoparticles based on DNA network templates

    International Nuclear Information System (INIS)

    Yao Yong; Song Yonghai; Wang Li

    2008-01-01

    CdS nanoparticles have been successfully synthesized by using DNA networks as templates. The synthesis was carried out by first dropping a mixture of cadmium acetate and DNA on a mica surface for the formation of the DNA network template and then transferring the sample into a heated thiourea solution. The Cd 2+ reacted with thiourea at high temperature and formed CdS nanoparticles on the DNA network template. UV-vis spectroscopy, photoluminescence, x-ray diffraction and atomic force microscopy (AFM) were used to characterize the CdS nanoparticles in detail. AFM results showed that the resulted CdS nanoparticles were directly aligned on the DNA network templates and that the synthesis and assembly of CdS nanoparticles was realized in one step. CdS nanoparticles fabricated with this method were smaller than those directly synthesized in a thiourea solution and were uniformly aligned on the DNA networks. By adjusting the density of the DNA networks and the concentration of Cd 2+ , the size and density of the CdS nanoparticles could be effectively controlled and CdS nanoparticles could grow along the DNA chains into nanowires. The possible growth mechanism has also been discussed in detail

  18. Improving the Formatting Tools of CDS Invenio

    CERN Document Server

    Caffaro, J; Pu Faltings, Pearl

    2006-01-01

    CDS Invenio is the web-based integrated digital library system developed at CERN. It is a strategical tool that supports the archival and open dissemination of documents produced by CERN researchers. This paper reports on my Master’s thesis work done on BibFormat, a module in CDS Invenio, which formats documents metadata. The goal of this project was to implement a completely new formatting module for CDS Invenio. In this report a strong emphasis is put on the user-centered design of the new BibFormat. The bibliographic formatting process and its requirements are discussed. The task analysis and its resulting interaction model are detailed. The document also shows the implemented user interface of BibFormat and gives the results of the user evaluation of this interface. Finally the results of a small usability study of the formats included in CDS Invenio are discussed.

  19. Dynamic Modeling of CDS Index Tranche Spreads

    DEFF Research Database (Denmark)

    Dorn, Jochen

    This paper provides a Market Model which implies a dynamics for standardized CDS index tranche spreads, i.e. tranches which securitise CDS index series and dispose of predefined subordination. This model is useful for pricing options on tranches with future Issue Dates as well as for modeling...... options on structured credit derivatives. With the upcoming regulation of the CDS market in perspective, the model presented here is also an attempt to face the effects on pricing approaches provoked by an eventual Clearing Chamber . It becomes also possible to calibrate Index Tranche Options with bespoke...... tenors/tranche subordination to market data obtained by more liquid Index Tranche Options with standard characteristics....

  20. Proton exchange mechanism of synthesizing CdS quantum dots in nafion

    International Nuclear Information System (INIS)

    Nandakumar, P.; Vijayan, C.; Murti, Y.V.G.S.; Dhanalakshmi, K.; Sundararajan, G.

    1999-01-01

    Nanocrystals of CdS are synthesized in the proton exchange membrane nafion in different sizes in the range 1.6 to 6 nm. To understand the process leading to the formation of these quantum dots, we have probed the proton exchange by ac conductance measurements in the frequency range 100 Hz to 13 MHz. Nafion shows good electrical conductivity due to proton transport probably via the Grothus mechanism. Incorporation of cadmium ions by replacement of the hydrogen ions in the sulphonic acid group resulted in a large decrease in conductance indicating the reduction of the mobile carrier density. The conductivity plots all show strong frequency dependence with higher conductance towards the higher frequencies where a near-flat frequency response is seen. After the formation of CdS clusters, there is a partial recovery of conductance corresponding to the reinstatement of the protonic carriers on the side groups. The conductivity of the nafion films embedded with the semiconductor quantum dots exhibits a size-dependence with the highest conductivity obtained for the largest clusters. These findings lend clear experimental evidence for the model of synthesis of quantum dots in nafion by the exchange mechanism. (author)

  1. Synthesis and Characterization of CdS Nanoparticles with Strong Electrolyte Behavior

    International Nuclear Information System (INIS)

    Zhang Yu; Fu, Degang; Liu Juzheng

    2000-01-01

    The CdS nanoparticles whose structure is similar to a strong electrolyte were synthesized by the colloidal chemical method. The CdS nanoparticles with Cd 2+ -rich surface are capped by the electrically neutral ligand of 2,2'-bipyridine (bpy), and the counterion, BPh 4 - , is adsorbed around the particle as balance charge. The ω donation from 2,2'-bipyridine at 2-position to the Cd 2+ -rich surface of the CdS nanoparticles was characterized by X-ray photoelectron spectroscopy (XPS). These CdS nanoparticles can redisperse in pyridine (py) or DMF, and have high stability. The determination of electroconductivity and the electrophoresis deposition in dilute solution containing the CdS nanoparticles further prove the rationality of the above electrolyte structure of the CdS nanoparticles

  2. GenBank blastx search result: AK061773 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061773 001-039-D01 U17242.1 Methylophilus methylotrophus electron transfer flavop...rotein small subunit and electron transfer flavoprotein large subunit genes, complete cds.|BCT BCT 1e-17 +3 ...

  3. GenBank blastx search result: AK243490 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243490 J100073N23 M90094.1 PHRRIBABH Photobacterium leiognathi riboflavin synthet...ase alpha subunit (ribB), riboflavin synthetase beta subunit (ribH), complete cds's. BCT 4e-26 1 ...

  4. GenBank blastx search result: AK241452 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241452 J065163N15 M90094.1 PHRRIBABH Photobacterium leiognathi riboflavin synthet...ase alpha subunit (ribB), riboflavin synthetase beta subunit (ribH), complete cds's. BCT 2e-71 1 ...

  5. GenBank blastx search result: AK058464 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058464 001-016-A10 M90094.1 Photobacterium leiognathi riboflavin synthetase alpha subunit (ribB), riboflav...in synthetase beta subunit (ribH), complete cds's.|BCT BCT 4e-69 +2 ...

  6. The CDS and the Government Bonds Markets During the Last Financial Crisis

    Directory of Open Access Journals (Sweden)

    Križanič France

    2015-11-01

    Full Text Available Financial market had developed a special instrument to insure the buyers of bonds. This instrument is so called Credit Default Swap (CDS. The CDS price is a kind of insurance premium that the buyer of CDS pays to the seller of CDS in exchange for compensation of possible loss in operation. Paper analyses causality between CDS price and dynamics of bond yields and influence of macroeconomic factors on it in four selected countries during the last financial crisis. Analysis results show that there is no important macroeconomic variable included in the analysis that preceded the CDS prices connected with German government bonds. Sellers of CDS were apparently aware of the systemic nature of the financial crisis in the euro area. In the case of the United Kingdom, Russia and Slovenia we can observe the unemployment rate as the most important macroeconomic variable that preceded the CDS prices for government bonds.

  7. GenBank blastx search result: AK104832 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104832 001-042-A09 L25604.2 Bacillus subtilis bmrU (bmrU) and multidrug-efflux transporter (bmr...) genes, complete cds; bmrR gene, complete sequence; multidrug-efflux transporter regulator (bmr

  8. Sulfonsuccinate (AOT Capped Pure and Mn-Doped CdS Nanoparticles

    Directory of Open Access Journals (Sweden)

    D. Venkatesan

    2012-01-01

    Full Text Available CdS nanoparticles and thin films are well known for their excellent semiconducting properties. When transition metal ions are doped into the CdS, it exhibits magnetic properties in addition to semiconducting properties and they are termed as dilute magnetic semiconductors (DMSs. In this paper, we discuss the preparation of sodium bis(2-ethylhexyl sulfonsuccinate (AOT capped CdS nanoparticles and thin films doped with magnetic impurity Mn. Sodium bis(2-ethulexyl sulfonsuccinate (AOT, capping agent promotes the uniform formation of nanoparticles. Optical characterizations are made using the UV-Vis spectrometer, PL, and FTIR. XRD shows the hexagonal structure of the CdS. SEM images and EDS measurements were made for the thin films. EPR shows the clear hyperfine lines corresponding to Mn2+ ion in the CdS nanoparticles.

  9. GenBank blastx search result: AK289049 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289049 J090092N07 BC098389.1 BC098389 Homo sapiens coagulation factor VIII, procoagulant component (hemoph...ilia A), mRNA (cDNA clone IMAGE:5284386), complete cds. PRI 0.0 0 ...

  10. GenBank blastx search result: AK289049 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289049 J090092N07 BC064380.1 BC064380 Homo sapiens coagulation factor VIII, procoagulant component (hemoph...ilia A), mRNA (cDNA clone IMAGE:5733897), complete cds. PRI 0.0 0 ...

  11. GenBank blastx search result: AK289049 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289049 J090092N07 BC022513.1 BC022513 Homo sapiens coagulation factor VIII, procoagulant component (hemoph...ilia A), mRNA (cDNA clone IMAGE:4815208), complete cds. PRI 0.0 0 ...

  12. GenBank blastx search result: AK060824 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060824 001-034-B04 U75295.1 Human fatty aldehyde dehydrogenase (ALDH10) gene, alternative...ly spliced exon 9', and complete cds for alternatively spliced product.|PRI PRI 3e-91 +1 ...

  13. GenBank blastx search result: AK104746 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104746 001-038-E07 U75295.1 Human fatty aldehyde dehydrogenase (ALDH10) gene, alternative...ly spliced exon 9', and complete cds for alternatively spliced product.|PRI PRI 1e-102 +2 ...

  14. The use of CDS/ISIS software in Africa | Abboy | Innovation

    African Journals Online (AJOL)

    CDS/ISIS is free-of-charge software that has been developed by UNESCO and is distributed through a network of country distributors and more recently through the World Wide Web. CDS/ISIS is ideally suited for the manipulation of bibliographic data. Literature sources reveal that the use of CDS/ISIS is widespread in Africa ...

  15. GenBank blastx search result: AK241698 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241698 J065196B09 U75295.1 HSALDHX10 Human fatty aldehyde dehydrogenase (ALDH10) gene, alternative...ly spliced exon 9', and complete cds for alternatively spliced product. PRI 4e-77 1 ...

  16. GenBank blastx search result: AK061773 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061773 001-039-D01 AF072475.1 Megasphaera elsdenii electron-transferring flavopro...tein b subunit (etfB) and electron-transferring flavoprotein a subunit (etfA) genes, complete cds.|BCT BCT 4e-27 +3 ...

  17. GenBank blastx search result: AK061941 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061941 001-042-D10 AF414084.1 Corynebacterium crenatum feedback-resistant asparto...kinase LysC alpha subunit and feedback-resistant aspartokinase LysC beta subunit genes, complete cds.|BCT BCT 2e-34 +2 ...

  18. GenBank blastx search result: AK287424 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287424 J043006K04 AF414084.1 AF414084 Corynebacterium crenatum feedback-resistant... aspartokinase LysC alpha subunit and feedback-resistant aspartokinase LysC beta subunit genes, complete cds. BCT 5e-24 0 ...

  19. Mechanistic aspects of biogenic synthesis of CdS nanoparticles using Bacillus licheniformis

    Science.gov (United States)

    Tripathi, R. M.; Singh Bhadwal, Akhshay; Singh, Priti; Shrivastav, Archana; Singh, M. P.; Shrivastav, B. R.

    2014-06-01

    A novel eco-friendly effort has been made for the synthesis of cadmium sulfide (CdS) nanoparticles using bacterial biomass. Although some articles have been reported on CdS nanoparticles synthesis by bacteria, here we have synthesized CdS nanoparticles using non-pathogenic bacteria Bacillus licheniformis MTCC 9555. UV-Vis spectroscopy was carried out to confirm the formation of CdS nanoparticles; the peak occurring at 368 nm gives the indication of synthesis of CdS nanoparticles. The size and morphology of the synthesized CdS nanoparticles were analyzed by transmission electron microscopy (TEM) and the nanoparticles are found to have a narrow size of 5.1 ± 0.5 nm with spherical morphology. Further, the nanoparticles were examined by energy dispersive x-ray (EDX) spectroscopy to identify the presence of elements and confirmed the existence of Cd and S in single nanoparticles. X-ray diffraction (XRD) analysis exhibited 2θ values corresponding to CdS nanocrystals. Fourier transform infrared spectroscopy (FTIR) provides the evidence for the presence of proteins as possible biomolecules responsible for the stabilization of the synthesized CdS nanoparticles.

  20. A comparative study of CdS thin films deposited by different techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pérez-Hernández, G., E-mail: german.perez@ujat.mx [Universidad Juárez Autónoma de Tabasco, Avenida Universidad s/n, Col. Magisterial, Villahermosa, Tabasco 86040 (Mexico); Pantoja-Enríquez, J. [Centro de Investigación y Desarrollo Tecnológico en Energías Renovables, UNICACH, Libramiento Norte No 1150, Tuxtla Gutiérrez, Chiapas 29039 (Mexico); Escobar-Morales, B. [Instituto Tecnológico de Cancún, Avenida Kábah Km 3, Cancún, Quintana Roo 77500 (Mexico); Martinez-Hernández, D.; Díaz-Flores, L.L.; Ricardez-Jiménez, C. [Universidad Juárez Autónoma de Tabasco, Avenida Universidad s/n, Col. Magisterial, Villahermosa, Tabasco 86040 (Mexico); Mathews, N.R.; Mathew, X. [Centro de Investigación en Energía, Universidad Nacional Autónoma de México, Temixco, Morelos 62580 (Mexico)

    2013-05-01

    Cadmium sulfide thin-films were deposited on glass slides and SnO{sub 2}:F coated glass substrates by chemical bath deposition, sputtering and close-spaced sublimation techniques. The films were studied for the structural and opto-electronic properties after annealing in an ambient identical to that employed in the fabrication of CdTe/CdS devices. Quantum efficiency of the CdTe/CdS solar cells fabricated with CdS buffer films prepared by the three methods were investigated to understand the role of CdS film preparation method on the blue response of the devices. The higher blue response observed for the devices fabricated with chemical bath deposited CdS film is discussed. - Highlights: ► CdS films were prepared by different techniques. ► Role of CdS on the blue response of device was studied. ► Structural and optical properties of CdS were analyzed. ► Chemically deposited CdS has high blue transmittance. ► CdS deposition method influences diffusion of S and Te.

  1. GenBank blastx search result: AK288647 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288647 J090056K16 BC096137.1 BC096137 Homo sapiens transition protein 2 (during histone to protamine repla...cement), mRNA (cDNA clone MGC:116785 IMAGE:40002553), complete cds. PRI 0.0 0 ...

  2. GenBank blastx search result: AK288647 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288647 J090056K16 BC096135.3 BC096135 Homo sapiens transition protein 2 (during histone to protamine repla...cement), mRNA (cDNA clone MGC:116782 IMAGE:40002547), complete cds. PRI 0.0 0 ...

  3. GenBank blastx search result: AK288647 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288647 J090056K16 BC096136.3 BC096136 Homo sapiens transition protein 2 (during histone to protamine repla...cement), mRNA (cDNA clone MGC:116783 IMAGE:40002550), complete cds. PRI 0.0 0 ...

  4. GenBank blastx search result: AK289049 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289049 J090092N07 BC111969.1 BC111969 Homo sapiens coagulation factor VIII, procoagulant component (hemoph...ilia A), transcript variant 2, mRNA (cDNA clone IMAGE:8327437), complete cds. PRI 0.0 0 ...

  5. GenBank blastx search result: AK289049 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289049 J090092N07 BC111967.1 BC111967 Homo sapiens coagulation factor VIII, procoagulant component (hemoph...ilia A), transcript variant 2, mRNA (cDNA clone IMAGE:8327435), complete cds. PRI 0.0 0 ...

  6. GenBank blastn search result: AK106868 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK106868 002-118-D05 AF335504.1 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobin... 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds.|PLN PLN 4e-13 Plus Minus ...

  7. GenBank blastn search result: AK240885 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240885 J065029A17 AF335504.1 AF335504 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobi...n 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds. PLN 0.0 1 1 ...

  8. GenBank blastn search result: AK109468 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK109468 001-128-C06 AF335504.1 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobin... 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds.|PLN PLN 2e-24 Plus Minus ...

  9. GenBank blastx search result: AK241096 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241096 J065076O13 AF335504.1 AF335504 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobi...n 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds. PLN 4e-79 1 ...

  10. GenBank blastx search result: AK240885 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240885 J065029A17 AF335504.1 AF335504 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobi...n 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds. PLN 7e-89 1 ...

  11. GenBank blastn search result: AK064054 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK064054 001-125-F02 AF335504.1 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobin... 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds.|PLN PLN 1e-179 Plus Plus ...

  12. GenBank blastn search result: AK073899 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK073899 J033072H18 AF335504.1 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobin... 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds.|PLN PLN 1e-106 Plus Minus ...

  13. GenBank blastn search result: AK060730 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060730 001-032-A03 AF335504.1 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobin... 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds.|PLN PLN 5e-17 Plus Minus ...

  14. Synthesis of CdS nanorods in soft template under gamma-irradiation.

    Science.gov (United States)

    Zhao, Bing; Wang, Yanli; Zhang, Haijiao; Jiao, Zheng; Wang, Haobo; Ding, Guoji; Wu, Minghong

    2009-02-01

    CdS nano material which has a band gap of 2.42 eV at room temperature is a typical II-VII semiconductor having many commercial or potential applications, e.g., light-emitting diodes, solar cell and optoelectronic devices. In this paper, we use a new strategy to synthesize CdS nanorods. CdS nanorods were prepared in soft template under gamma-irradiation though the reaction of cadmium sulphide and thiacetamide (TAA). The formation process and characters of CdS nanorods was investigated in detail by transmission electron microscopy (TEM), electron diffraction (ED) pattern, X-ray powder diffraction (XRD), ultraviolet spectrophotometer (UV) and photoluminescence spectrophotometer (PL). In the experiment we proposed that the irradiation of gamma-ray accelerated the formation of S(2-) under acidic condition (pH = 3) and vinyl acetate (VAc) monomer formed pre-organized nano polymer tubules which were used as both templates and nanoreacters for the growth of CdS nanorods. In this process, we have obtained the CdS polycrystal nanorods with PVAc nano tubules and CdS single-crystal nanorods. The result of X-ray powder diffraction confirms that the crystal type of CdS nanorods is cubic F-43 m (216). The results from transmission electron microscopy and electron diffraction show that the concentrations of reactants and the dose rate of gamma-ray are key to produce appropriate CdS nanorods. Relatively low concentrations (Cd2+: 0.008-0.02 mol/L, Cd2+ : S(2-) = 1 : 2) of reactants and long time (1-2 d) of irradiation in low dose rate (6-14 Gy/min) are propitious to form CdS single-crystal nanorods with small diameter (less than 100 nm) and well length (2-5 microm). UV and PL characterizations show the sample have well optical properties.

  15. Enriching The Metadata On CDS

    CERN Document Server

    Chhibber, Nalin

    2014-01-01

    The project report revolves around the open source software package called Invenio. It provides the tools for management of digital assets in a repository and drives CERN Document Server. Primary objective is to enhance the existing metadata in CDS with data from other libraries. An implicit part of this task is to manage disambiguation (within incoming data), removal of multiple entries and handle replications between new and existing records. All such elements and their corresponding changes are integrated within Invenio to make the upgraded metadata available on the CDS. Latter part of the report discuss some changes related to the Invenio code-base itself.

  16. GenBank blastx search result: AK110605 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110605 002-168-G09 BC097157.1 Danio rerio similar to Myeloid leukemia factor 2 (Myelodysplasia-myeloid leu...kemia factor 2), mRNA (cDNA clone MGC:114097 IMAGE:7448089), complete cds.|VRT VRT 6e-15 +3 ...

  17. GenBank blastx search result: AK104746 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104746 001-038-E07 AY841893.1 Methylomonas sp. 16a diapophytoene desaturase (crtN), 4, 4'-diapolycopene...-dialdehyde dehydrogenase (ald), and 4, 4'-diapolycopene oxidase (crtNb) genes, complete cds.|BCT BCT 1e-33 +2 ...

  18. GenBank blastx search result: AK060824 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060824 001-034-B04 AY841893.1 Methylomonas sp. 16a diapophytoene desaturase (crtN), 4, 4'-diapolycopene...-dialdehyde dehydrogenase (ald), and 4, 4'-diapolycopene oxidase (crtNb) genes, complete cds.|BCT BCT 4e-36 +1 ...

  19. GenBank blastx search result: AK111983 [KOME

    Lifescience Database Archive (English)

    Full Text Available ative exons 18 and 18a, and alternative splice products, complete cds.|ROD ROD 4e-34 +3 ... ...AK111983 001-012-H11 AF071946.1 Mus musculus protein tyrosine kinase Tec (Tec) gene, exons 16 and 17, altern

  20. GenBank blastx search result: AK061938 [KOME

    Lifescience Database Archive (English)

    Full Text Available ative exons 18 and 18a, and alternative splice products, complete cds.|ROD ROD 1e-24 +2 ... ...AK061938 001-042-D07 AF071946.1 Mus musculus protein tyrosine kinase Tec (Tec) gene, exons 16 and 17, altern

  1. GenBank blastx search result: AK060220 [KOME

    Lifescience Database Archive (English)

    Full Text Available ative exons 18 and 18a, and alternative splice products, complete cds.|ROD ROD 2e-36 +3 ... ...AK060220 001-002-F01 AF071946.1 Mus musculus protein tyrosine kinase Tec (Tec) gene, exons 16 and 17, altern

  2. GenBank blastx search result: AK059663 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK059663 001-031-E04 AB063318.1 Homo sapiens MoDP-2, MoDP-3 mRNA for acute morphine dependence... related protein 2, acute morphine dependence related peptide 3, complete cds.|PRI PRI 7e-29 +3 ...

  3. GenBank blastx search result: AK059413 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK059413 001-027-D02 AB063318.1 Homo sapiens MoDP-2, MoDP-3 mRNA for acute morphine dependence... related protein 2, acute morphine dependence related peptide 3, complete cds.|PRI PRI 9e-12 +1 ...

  4. GenBank blastx search result: AK062146 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062146 001-045-G12 AB063318.1 Homo sapiens MoDP-2, MoDP-3 mRNA for acute morphine dependence... related protein 2, acute morphine dependence related peptide 3, complete cds.|PRI PRI 2e-80 +1 ...

  5. GenBank blastx search result: AK287855 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287855 J065196O16 AB091060.1 AB091060 Gluconacetobacter xylinus acsAB, acsC, acsD genes for cellulose... synthase subunit AB, cellulose synthase subunit C, cellulose synthase subunit D, complete cds. BCT 4e-15 0 ...

  6. GenBank blastx search result: AK242831 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242831 J090067L08 AB091060.1 AB091060 Gluconacetobacter xylinus acsAB, acsC, acsD genes for cellulose... synthase subunit AB, cellulose synthase subunit C, cellulose synthase subunit D, complete cds. BCT 1e-14 1 ...

  7. GenBank blastn search result: AK241681 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241681 J065193N01 AF335504.1 AF335504 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobi...n 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds. PLN 3e-34 1 1 ...

  8. GenBank blastn search result: AK318581 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK318581 J090090I16 AF335504.1 AF335504 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobi...n 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds. PLN 1e-23 1 -1 ...

  9. GenBank blastn search result: AK241096 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241096 J065076O13 AF335504.1 AF335504 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobi...n 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds. PLN 6e-56 1 1 ...

  10. GenBank blastn search result: AK289024 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289024 J090090I16 AF335504.1 AF335504 Oryza sativa (japonica cultivar-group) hemoglobin 1 (hb1), hemoglobi...n 3 (hb3), and hemoglobin 4 (hb4) genes, complete cds. PLN 9e-24 1 -1 ...

  11. Ultrasonic/surfactant assisted of CdS nano hollow sphere synthesis and characterization

    International Nuclear Information System (INIS)

    Rafati, Amir Abbas; Borujeni, Ahmad Reza Afraz; Najafi, Mojgan; Bagheri, Ahmad

    2011-01-01

    CdS hollow nanospheres with diameters ranging from 40 to 150 nm have been synthesized by a surfactant-assisted sonochemical route. The successful vesicle templating indicates that the outer leaflet of the bilayer is the receptive surface in the controlled growth of CdS nanoparticles which provide the unique reactor for the nucleation and mineralization growth of CdS nanoparticles. The CdS nanostructures obtained were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet-visible spectroscopy and photoluminescence spectroscopy. Structural characterization of hollow CdS nanospheres indicates that these products packed with square subunits having sizes between 5 and 7 nm in diameter. The formation of the hollow nanostructure was explained by a vesicle template mechanism, in which sonication and surfactant play important roles. The band-edge emission and surface luminescence of the CdS nanoparticles were observed. -Research Highlights: → CdS hollow nanospheres with diameters of 40-150 nm were synthesized. → Nanoparticles were characterized by UV/Vis and photoluminescence. → Nanospheres are composed of smaller nanocrystals with the average size of 6.8 nm. → The band gap energy of the CdS nanoparticles is higher than its bulk value.

  12. Mechanistic aspects of biogenic synthesis of CdS nanoparticles using Bacillus licheniformis

    International Nuclear Information System (INIS)

    Tripathi, R M; Shrivastav, Archana; Bhadwal, Akhshay Singh; Singh, Priti; Singh, M P; Shrivastav, B R

    2014-01-01

    A novel eco-friendly effort has been made for the synthesis of cadmium sulfide (CdS) nanoparticles using bacterial biomass. Although some articles have been reported on CdS nanoparticles synthesis by bacteria, here we have synthesized CdS nanoparticles using non-pathogenic bacteria Bacillus licheniformis MTCC 9555. UV-Vis spectroscopy was carried out to confirm the formation of CdS nanoparticles; the peak occurring at 368 nm gives the indication of synthesis of CdS nanoparticles. The size and morphology of the synthesized CdS nanoparticles were analyzed by transmission electron microscopy (TEM) and the nanoparticles are found to have a narrow size of 5.1 ± 0.5 nm with spherical morphology. Further, the nanoparticles were examined by energy dispersive x-ray (EDX) spectroscopy to identify the presence of elements and confirmed the existence of Cd and S in single nanoparticles. X-ray diffraction (XRD) analysis exhibited 2θ values corresponding to CdS nanocrystals. Fourier transform infrared spectroscopy (FTIR) provides the evidence for the presence of proteins as possible biomolecules responsible for the stabilization of the synthesized CdS nanoparticles. (papers)

  13. GenBank blastx search result: AK059236 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK059236 001-024-F01 AB016078.1 Rhodococcus sp. N-771 genes for nitrile hydratase r...egulator 2 and 1, amidase, nitrile hydratase alpha and beta subunits and nitrile hydratase activator, complete cds.|BCT BCT 8e-18 +3 ...

  14. GenBank blastx search result: AK243402 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243402 J100064O18 AB016078.1 AB016078 Rhodococcus sp. N-771 genes for nitrile hyd...ratase regulator 2 and 1, amidase, nitrile hydratase alpha and beta subunits and nitrile hydratase activator, complete cds. BCT 1e-27 1 ...

  15. GenBank blastx search result: AK241698 [KOME

    Lifescience Database Archive (English)

    Full Text Available opene-dialdehyde dehydrogenase (ald), and 4, 4'-diapolycopene oxidase (crtNb) genes, complete cds. BCT 6e-30 1 ... ...AK241698 J065196B09 AY841893.1 AY841893 Methylomonas sp. 16a diapophytoene desaturase (crtN), 4, 4'-diapolyc

  16. GenBank blastx search result: AK062242 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:14115 IMAGE:3938510), complete cds.|PRI PRI 3e-31 +1 ... ...AK062242 001-047-E10 BC007878.2 Homo sapiens branched chain keto acid dehydrogenase

  17. GenBank blastx search result: AK110760 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:14115 IMAGE:3938510), complete cds.|PRI PRI 1e-100 +1 ... ...AK110760 002-170-H05 BC007878.2 Homo sapiens branched chain keto acid dehydrogenase

  18. GenBank blastx search result: AK060732 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:22893 IMAGE:4065221), complete cds.|PRI PRI 1e-113 +3 ... ...AK060732 001-032-A05 BC023983.1 Homo sapiens branched chain keto acid dehydrogenase

  19. GenBank blastx search result: AK062242 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:22893 IMAGE:4065221), complete cds.|PRI PRI 3e-31 +1 ... ...AK062242 001-047-E10 BC023983.1 Homo sapiens branched chain keto acid dehydrogenase

  20. GenBank blastx search result: AK104686 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104686 001-036-C11 BC034481.1 Homo sapiens branched chain keto acid dehydrogenase... E1, beta polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:26350 IMAGE:4824846), complete cds.|PRI PRI 3e-20 +1 ...

  1. GenBank blastx search result: AK060732 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:14115 IMAGE:3938510), complete cds.|PRI PRI 1e-113 +3 ... ...AK060732 001-032-A05 BC007878.2 Homo sapiens branched chain keto acid dehydrogenase

  2. GenBank blastx search result: AK061863 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061863 001-040-H03 BC034481.1 Homo sapiens branched chain keto acid dehydrogenase... E1, beta polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:26350 IMAGE:4824846), complete cds.|PRI PRI 2e-18 +2 ...

  3. GenBank blastx search result: AK110760 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:2355 IMAGE:2822372), complete cds.|PRI PRI 1e-100 +1 ... ...AK110760 002-170-H05 BC008933.2 Homo sapiens branched chain keto acid dehydrogenase

  4. GenBank blastx search result: AK060732 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:2355 IMAGE:2822372), complete cds.|PRI PRI 1e-113 +3 ... ...AK060732 001-032-A05 BC008933.2 Homo sapiens branched chain keto acid dehydrogenase

  5. GenBank blastx search result: AK105105 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:22893 IMAGE:4065221), complete cds.|PRI PRI 2e-26 +3 ... ...AK105105 001-100-E08 BC023983.1 Homo sapiens branched chain keto acid dehydrogenase

  6. GenBank blastx search result: AK105105 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:14115 IMAGE:3938510), complete cds.|PRI PRI 2e-26 +3 ... ...AK105105 001-100-E08 BC007878.2 Homo sapiens branched chain keto acid dehydrogenase

  7. GenBank blastx search result: AK062242 [KOME

    Lifescience Database Archive (English)

    Full Text Available E1, alpha polypeptide (maple syrup urine disease), mRNA (cDNA clone MGC:2355 IMAGE:2822372), complete cds.|PRI PRI 3e-31 +1 ... ...AK062242 001-047-E10 BC008933.2 Homo sapiens branched chain keto acid dehydrogenase

  8. GenBank blastx search result: AK242135 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242135 J075149M11 AB063318.1 AB063318 Homo sapiens MoDP-2, MoDP-3 mRNA for acute morphine dependence... related protein 2, acute morphine dependence related peptide 3, complete cds. PRI 4e-38 1 ...

  9. ORF Sequence: cds [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available KGSWTFYIMLLASFRIFFGLGLSLSPMESWTIMNVVHAGVTFIVFHWIKGNPFHTPWVDMMGKGEKQTWWEQIDGSVQNTPSRKFLICVVVFLYLAAVHSTPFERQFFFVHAVNLIAFLVVFVAKLPFMHGVRIFGINR ... cds gnl|CMER >gnl|CMER|CMQ020C hypothetical protein, conserved MQSGHGETRFDVGVEWLRA

  10. GenBank blastx search result: AK105761 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK105761 001-202-D07 BC040139.2 Homo sapiens branched chain keto acid dehydrogenase... E1, beta polypeptide (maple syrup urine disease), transcript variant 1, mRNA (cDNA clone MGC:48849 IMAGE:5493159), complete cds.|PRI PRI 1e-115 +2 ...

  11. GenBank blastx search result: AK104686 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104686 001-036-C11 BC040139.2 Homo sapiens branched chain keto acid dehydrogenase... E1, beta polypeptide (maple syrup urine disease), transcript variant 1, mRNA (cDNA clone MGC:48849 IMAGE:5493159), complete cds.|PRI PRI 1e-48 +1 ...

  12. GenBank blastx search result: AK061863 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061863 001-040-H03 BC040139.2 Homo sapiens branched chain keto acid dehydrogenase... E1, beta polypeptide (maple syrup urine disease), transcript variant 1, mRNA (cDNA clone MGC:48849 IMAGE:5493159), complete cds.|PRI PRI 2e-47 +2 ...

  13. The fluorescence quenching mechanism of coumarin 120 with CdS nanoparticles in aqueous suspension

    Energy Technology Data Exchange (ETDEWEB)

    Acar, Murat; Bozkurt, Ebru; Meral, Kadem; Arık, Mustafa; Onganer, Yavuz, E-mail: yonganer@atauni.edu.tr

    2015-01-15

    The interaction of coumarin 120 (C120) with CdS nanoparticles (CdS NPs) in aqueous suspension was examined by using UV–vis absorption, steady-state, time-resolved fluorescence, and electron paramagnetic resonance (EPR) spectroscopy techniques. The fluorescence intensity of C120 was quenched with increasing the amount of CdS NPs in the aqueous suspension. The spectroscopic data revealed that the C120 molecules adsorbed on CdS NPs via electrostatic interactions. The apparent association constant (K{sub app}) and the degree of association (α) for C120/CdS NPs were determined as 130.3 M{sup −1} and 0.51 for 4 nm CdS NPs and 624.3 M{sup −1} and 0.71 for 8 nm CdS NPs, respectively. The photoinduced EPR studies exhibited that no electron transfers between CdS and C120 taking place. The results revealed that the fluorescence quenching of C120 with different CdS NPs is due to the formation of a non-fluorescent complex. - Highlights: • Interaction of C120 with CdS NPs in aqueous solution was spectroscopically examined. • Nonfluorescent C120–CdS NPs complexes in aqueous solution were formed. • In the system, CdS NPs in aqueous solution acted as a fluorescence quencher.

  14. The fluorescence quenching mechanism of coumarin 120 with CdS nanoparticles in aqueous suspension

    International Nuclear Information System (INIS)

    Acar, Murat; Bozkurt, Ebru; Meral, Kadem; Arık, Mustafa; Onganer, Yavuz

    2015-01-01

    The interaction of coumarin 120 (C120) with CdS nanoparticles (CdS NPs) in aqueous suspension was examined by using UV–vis absorption, steady-state, time-resolved fluorescence, and electron paramagnetic resonance (EPR) spectroscopy techniques. The fluorescence intensity of C120 was quenched with increasing the amount of CdS NPs in the aqueous suspension. The spectroscopic data revealed that the C120 molecules adsorbed on CdS NPs via electrostatic interactions. The apparent association constant (K app ) and the degree of association (α) for C120/CdS NPs were determined as 130.3 M −1 and 0.51 for 4 nm CdS NPs and 624.3 M −1 and 0.71 for 8 nm CdS NPs, respectively. The photoinduced EPR studies exhibited that no electron transfers between CdS and C120 taking place. The results revealed that the fluorescence quenching of C120 with different CdS NPs is due to the formation of a non-fluorescent complex. - Highlights: • Interaction of C120 with CdS NPs in aqueous solution was spectroscopically examined. • Nonfluorescent C120–CdS NPs complexes in aqueous solution were formed. • In the system, CdS NPs in aqueous solution acted as a fluorescence quencher

  15. ORF Sequence: cds [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available cds gnl|CMER >gnl|CMER|CME069C hypothetical protein MQSGSSEERVSSHMEARDSAPTASSMPSLRLTATATATATAR...LTYAHVSRPRPPAHLPRSDAYGGSPSASTTSSSTATARPTCAHEAAHPPQVHHLGSGACGGSPSASTTSSSTATARPTCAHEAAHPPQVHHLGSGACDGSPSASTTSSSTATAR...PTCAHEAAHPPQVHRLGSGACGGSPSASTTSSSTATARPTCAHEAAHPPQVHRLGSGACGGSPSASTTSSSTATARPTCAHEADHPPQVHRQGSDVSHINHTTKKLLSLWLLARPTATVKATVKVLRSDARRCGPDLSTTAEQARCNCREQCRSRTHR

  16. Chemical synthesis of porous web-structured CdS thin films for photosensor applications

    Energy Technology Data Exchange (ETDEWEB)

    Gosavi, S.R., E-mail: srgosavi.taloda@gmail.com [C. H. C. Arts, S. G. P. Commerce, and B. B. J. P. Science College, Taloda, Dist., Nandurbar 425413, M. S. (India); Nikam, C.P. [B.S.S.P.M.S. Arts, Commerce and Science College, Songir, Dist., Dhule 424309, M. S. (India); Shelke, A.R.; Patil, A.M. [Department of Physics, Shivaji University, Kolhapur 416004, M.S. (India); Ryu, S.-W. [Department of Physics, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Bhat, J.S. [Department of Physics, Karnatak University, Dharwad 580003 (India); Deshpande, N.G., E-mail: nicedeshpande@yahoo.co.in [Department of Physics, Shivaji University, Kolhapur 416004, M.S. (India)

    2015-06-15

    The photo-activity of chemically deposited cadmium sulphide (CdS) thin film has been studied. The simple chemical route nucleates the CdS films with size up to the mean free path of the electron. Growth Kinematics of crystalline hexagonal CdS phase in the thin film form was monitored using X-ray diffraction. The time limitation set for the formation of the amorphous/nano-crystalline material is 40 and 60 min. Thereafter enhancement of the crystalline orientation along the desired plane was identified. Web-like porous structured surface morphology of CdS thin film over the entire area is observed. With decrease in synthesis time, increase of band gap energy i.e., a blue spectral shift was seen. The activation energy of CdS thin film at low and high temperature region was examined. It is considered that this activation energy corresponds to the donor levels associated with shallow traps or surface states of CdS thin film. The photo-electrochemical performance of CdS thin films in polysulphide electrolyte showed diode-like characteristics. Exposure of light on the CdS electrode increases the photocurrent. This suggests the possibility of production of free carriers via excited ions and also the light harvesting mechanism due to porous web-structured morphology. These studies hint that the obtained CdS films can work as a photosensor. - Highlights: • Photoactivity of chemically synthesized cadmium sulphide (CdS) thin films was studied. • Web-like porous structured surface morphology of CdS thin film over the entire area was observed. • Blue spectral shift with lowering of the synthesis time suggests films can act as a window layer over the absorber layer. • Porous web-structured CdS thin films can be useful in light harvesting.

  17. Chemical synthesis of porous web-structured CdS thin films for photosensor applications

    International Nuclear Information System (INIS)

    Gosavi, S.R.; Nikam, C.P.; Shelke, A.R.; Patil, A.M.; Ryu, S.-W.; Bhat, J.S.; Deshpande, N.G.

    2015-01-01

    The photo-activity of chemically deposited cadmium sulphide (CdS) thin film has been studied. The simple chemical route nucleates the CdS films with size up to the mean free path of the electron. Growth Kinematics of crystalline hexagonal CdS phase in the thin film form was monitored using X-ray diffraction. The time limitation set for the formation of the amorphous/nano-crystalline material is 40 and 60 min. Thereafter enhancement of the crystalline orientation along the desired plane was identified. Web-like porous structured surface morphology of CdS thin film over the entire area is observed. With decrease in synthesis time, increase of band gap energy i.e., a blue spectral shift was seen. The activation energy of CdS thin film at low and high temperature region was examined. It is considered that this activation energy corresponds to the donor levels associated with shallow traps or surface states of CdS thin film. The photo-electrochemical performance of CdS thin films in polysulphide electrolyte showed diode-like characteristics. Exposure of light on the CdS electrode increases the photocurrent. This suggests the possibility of production of free carriers via excited ions and also the light harvesting mechanism due to porous web-structured morphology. These studies hint that the obtained CdS films can work as a photosensor. - Highlights: • Photoactivity of chemically synthesized cadmium sulphide (CdS) thin films was studied. • Web-like porous structured surface morphology of CdS thin film over the entire area was observed. • Blue spectral shift with lowering of the synthesis time suggests films can act as a window layer over the absorber layer. • Porous web-structured CdS thin films can be useful in light harvesting

  18. One-pot solvothermal route to self-assembly of cauliflower-shaped CdS microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Ge Ming [Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300071 (China); Cui Yao [Institute of New Energy Material Chemistry, and Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Nankai University, Tianjin 300071 (China); Liu Lu, E-mail: liul@nankai.edu.cn [Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300071 (China); Zhou Zhen, E-mail: zhouzhen@nankai.edu.cn [Institute of New Energy Material Chemistry, and Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Nankai University, Tianjin 300071 (China)

    2011-05-15

    Nearly monodispersed cauliflower-shaped CdS microspheres were prepared through a simple one-step solvothermal route on a large scale by employing sodium dodecyl sulfate (SDS) as the surfactant. Images by field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM) indicate that cauliflower-shaped CdS microspheres with diameters in the range from 1.3 to 4.5 {mu}m are assembled by nanoparticles with an average diameter of approximately 30 nm. The possible formation mechanism of the cauliflower-shaped CdS microspheres was also proposed. The photovoltaic activity of cauliflower-shaped CdS architectures has been investigated, indicating that the as-obtained CdS microspheres exhibited higher photovoltaic performance in comparison with CdS nanoparticles.

  19. GenBank blastx search result: AK242401 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242401 J080068F24 AF179596.1 AF179596 Vibrio cholerae 569b mega-integron MInVc Vco27A, Vco27B, Vco28 (vco2...8), Vco29 (vco29), ORF23 genes, complete cds; insertion sequence IS1359 putative tr

  20. GenBank blastx search result: AK318593 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK318593 J100055K16 J02708.1 ECOGUT E.coli glucitol (gut) operon: glucitol-specific enzyme II (gut...A), and III (gutB), glucitol-6-phosphate dehydrogenase (gutD), activator (gutM) and repressor (gutR) genes, complete cds. BCT 0.0 1 ...

  1. Complete Mitochondrial Genomes of the Cherskii’s Sculpin and Siberian Taimen Reveal GenBank Entry Errors: Incorrect Species Identification and Recombinant Mitochondrial Genome

    Directory of Open Access Journals (Sweden)

    Evgeniy S Balakirev

    2017-08-01

    Full Text Available The complete mitochondrial (mt genome is sequenced in 2 individuals of the Cherskii’s sculpin Cottus czerskii . A surprisingly high level of sequence divergence (10.3% has been detected between the 2 genomes of C czerskii studied here and the GenBank mt genome of C czerskii (KJ956027. At the same time, a surprisingly low level of divergence (1.4% has been detected between the GenBank C czerskii (KJ956027 and the Amur sculpin Cottus szanaga (KX762049, KX762050. We argue that the observed discrepancies are due to incorrect taxonomic identification so that the GenBank accession number KJ956027 represents actually the mt genome of C szanaga erroneously identified as C czerskii . Our results are of consequence concerning the GenBank database quality, highlighting the potential negative consequences of entry errors, which once they are introduced tend to be propagated among databases and subsequent publications. We illustrate the premise with the data on recombinant mt genome of the Siberian taimen Hucho taimen (NCBI Reference Sequence Database NC_016426.1; GenBank accession number HQ897271.1, bearing 2 introgressed fragments (≈0.9 kb [kilobase] from 2 lenok subspecies, Brachymystax lenok and Brachymystax lenok tsinlingensis , submitted to GenBank on June 12, 2011. Since the time of submission, the H taimen recombinant mt genome leading to incorrect phylogenetic inferences was propagated in multiple subsequent publications despite the fact that nonrecombinant H taimen genomes were also available (submitted to GenBank on August 2, 2014; KJ711549, KJ711550. Other examples of recombinant sequences persisting in GenBank are also considered. A GenBank Entry Error Depositary is urgently needed to monitor and avoid a progressive accumulation of wrong biological information.

  2. HDR-Clinical Data Service (CDS)

    Data.gov (United States)

    Department of Veterans Affairs — CDS is a SOAP/REST web service interface that supports Create, Retrieve, Update, and Delete (CRUD) operations against HDR data stores over secure Hypertext Transfer...

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  4. Effects of bacteria on CdS thin films used in technological devices

    Science.gov (United States)

    Alpdoğan, S.; Adıgüzel, A. O.; Sahan, B.; Tunçer, M.; Metin Gubur, H.

    2017-04-01

    Cadmium sulfide (CdS) thin films were fabricated on glass substrates by the chemical bath deposition method at 70 {}^\\circ \\text{C} considering deposition times ranging from 2 h to 5 h. The optical band gaps of CdS thin films were found to be in the 2.42-2.37 eV range. CdS thin films had uniform spherical nano-size grains which had polycrystalline, hexagonal and cubic phases. The films had a characteristic electrical resistivity of the order of {{10}5} Ω \\text{cm} and n-type conductivity at room condition. CdS thin films were incubated in cultures of B.domonas aeruginosa and Staphylococcus aureus, which exist abundantly in the environment, and form biofilms. SEM images showed that S. aureus and K. pneumonia were detected significantly on the film surfaces with a few of P. aeruginosa and B. subtilis cells attached. CdS thin film surface exhibits relatively good resistance to the colonization of P. aeruginosa and B. subtilis. Optical results showed that the band gap of CdS thin films which interacted with the bacteria is 2.42 \\text{eV} . The crystal structure and electrical properties of CdS thin films were not affected by bacterial adhesion. The antimicrobial effect of CdS nanoparticles was different for different bacterial strains.

  5. Re-dispersible Li+ and Eu3+ co-doped CdS nanoparticles ...

    Indian Academy of Sciences (India)

    Also, it can be used as sensor for drug delivery in our body [12,13]. In the present work, we prepare re-dispersible CdS, Li+- and Eu3+-doped CdS nanoparticles in organic solvent by urea hydrolysis at 170◦C and their lumines- cence properties are studied. We propose the mechanism of re-dispersion of CdS nanoparticles ...

  6. Preparation of CdS Nanoparticles by First-Year Undergraduates

    Science.gov (United States)

    Winkelmann, Kurt; Noviello, Thomas; Brooks, Stephen

    2007-01-01

    The first year undergraduates use a simple method to synthesize 5-nm CdS nanoparticles in a water-in-oil microemulsion. The quantum size effect, the relationship between colors, optical absorbance, band-gap energy and the CdS particles affected by the formation of micelles are observed.

  7. Broad spectral response photodetector based on individual tin-doped CdS nanowire

    Directory of Open Access Journals (Sweden)

    Weichang Zhou

    2014-12-01

    Full Text Available High purity and tin-doped 1D CdS micro/nano-structures were synthesized by a convenient thermal evaporation method. SEM, EDS, XRD and TEM were used to examine the morphology, composition, phase structure and crystallinity of as-prepared samples. Raman spectrum was used to confirm tin doped into CdS effectively. The effect of impurity on the photoresponse properties of photodetectors made from these as-prepared pure and tin-doped CdS micro/nano-structures under excitation of light with different wavelength was investigated. Various photoconductive parameters such as responsivity, external quantum efficiency, response time and stability were analyzed to evaluate the advantage of doped nanowires and the feasibility for photodetector application. Comparison with pure CdS nanobelt, the tin-doped CdS nanowires response to broader spectral range while keep the excellect photoconductive parameters. Both trapped state induced by tin impurity and optical whispering gallery mode microcavity effect in the doped CdS nanowires contribute to the broader spectral response. The micro-photoluminescence was used to confirm the whispering gallery mode effect and deep trapped state in the doped CdS nanowires.

  8. Microwave assisted synthesis of CdS nanoparticles and their size evolution

    International Nuclear Information System (INIS)

    Lopez, I. A.; Vazquez, A.; Gomez, I.

    2013-01-01

    The study of the size evolution of CdS nanoparticles in aqueous dispersion is presented in this paper. The sodium citrate was employed as stabilizer of CdS nanoparticles synthesized by microwave assisted synthesis. Analysis of this study was carried out by UV-Vis spectrophotometry, by comparison of the band gap energy using theoretical and empirical models. Results obtained show that the synthesis conditions produce CdS nanoparticles with diameters below of 6 nm, which remains stabilized by at least 14 days. These characteristics were confirmed by transmission electron microscopy. The X-ray diffraction pattern confirms cubic phase of the CdS nanoparticles. (Author)

  9. Microwave assisted synthesis of CdS nanoparticles and their size evolution

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, I. A.; Vazquez, A.; Gomez, I., E-mail: idaliagomezmx@yahoo.com.mx [Universidad Autonoma de Nuevo Leon, Facultad de Ciencias Quimicas, Laboratorio de Materiales I, Av. Universidad, Cd. Universitaria, 66451 San Nicolas de los Garza, Nuevo Leon (Mexico)

    2013-05-01

    The study of the size evolution of CdS nanoparticles in aqueous dispersion is presented in this paper. The sodium citrate was employed as stabilizer of CdS nanoparticles synthesized by microwave assisted synthesis. Analysis of this study was carried out by UV-Vis spectrophotometry, by comparison of the band gap energy using theoretical and empirical models. Results obtained show that the synthesis conditions produce CdS nanoparticles with diameters below of 6 nm, which remains stabilized by at least 14 days. These characteristics were confirmed by transmission electron microscopy. The X-ray diffraction pattern confirms cubic phase of the CdS nanoparticles. (Author)

  10. Rapid biosynthesis of cadmium sulfide (CdS) nanoparticles using ...

    African Journals Online (AJOL)

    Rapid biosynthesis of cadmium sulfide (CdS) nanoparticles using culture supernatants of Escherichia coli ATCC 8739, Bacillus subtilis ATCC 6633 and Lactobacillus ... The process of extracellular and fast biosynthesis may help in the development of an easy and eco-friendly route for the synthesis of CdS nanoparticles.

  11. Regime-dependent determinants of Euro area sovereign CDS spreads

    NARCIS (Netherlands)

    Blommestein, H.J.; Eijffinger, Sylvester; Qian, Zongxin

    We study the determinants of sovereign CDS spreads of five Euro area countries (Greece, Ireland, Italy, Portugal, and Spain) after the collapse of Lehman Brothers. We find that global and/or European Monetary Union (EMU)-wide factors are the main drivers of changes in the sovereign CDS spreads in

  12. GenBank blastx search result: AK110598 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110598 002-168-G02 AF026065.1 Ralstonia sp. E2 positive phenol-degradative gene regulator (pox...R), phenol hydroxylase components (poxA, poxB, poxC, poxD, poxE, poxF), and ferredoxin-like protein (poxG) genes, complete cds.|BCT BCT 1e-78 +2 ...

  13. Summer Student Project: Collecting and disseminating CDS KPIs

    CERN Document Server

    Alvarez Perez, Carmen

    2010-01-01

    CDS (CERN Document Server) stores over 900,000 bibliographic records, including 360,000 fulltext documents, of interest to people working in particle physics and related areas. My project consisted on extracting KPIs (Key Performance Indicators) from it and feeding them to a central IT KPI system. To achieve this, I learned the CDS-Invenio open source digital library software, and worked with its statistic module.

  14. Effect of silver doping on the elastic properties of CdS nanoparticles

    Science.gov (United States)

    Dey, P. C.; Das, R.

    2018-05-01

    CdS and Ag doped CdS (CdS/Ag) nanoparticles have been prepared via chemical method from a Cadmium acetate precursor and Thiourea. The synthesized CdS and CdS/Ag nanoparticles have been characterized by the X-ray Diffraction and High Resolution Transmission Electron Microscope. Here, these nanoparticles have been synthesized at room temperature and all the characterization have also been done at room temperature only. The XRD results reveal that the products are crystalline with cubic zinc blende structure. HRTEM images show that the prepared nanoparticles are nearly spherical in shape. Williamson-Hall method and Size-Strain Plot (SSP) have been used to study the individual contribution of crystalline sizes and lattice strain on the peak broadening of the CdS and CdS/Ag nanoparticles. The different modified model of Williamson-Hall method such as, uniform deformation model, uniform stress deformation model and uniform energy density deformation model and SSP method have been used to calculate the different physical parameter such as lattice strain, stress and energy density for all diffraction peaks of the XRD, corresponding to the CdS and silver doped CdS (CdS/Ag). The obtained results reveal that the average particle size of the prepared CdS and CdS/Ag nanoparticles estimated from the HRTEM images, Williamson-Hall analysis and SSP method are highly correlated with each other. Further, all these result confirms that doping of Ag significantly affects the elastic properties of CdS.

  15. Solution precursor plasma deposition of nanostructured CdS thin films

    International Nuclear Information System (INIS)

    Tummala, Raghavender; Guduru, Ramesh K.; Mohanty, Pravansu S.

    2012-01-01

    Highlights: ► Inexpensive process with capability to produce large scale nanostructured coatings. ► Technique can be employed to spray the coatings on any kind of substrates including polymers. ► The CdS coatings developed have good electrical conductivity and optical properties. ► Coatings possess large amount of particulate boundaries and nanostructured grains. -- Abstract: Cadmium sulfide (CdS) films are used in solar cells, sensors and microelectronics. A variety of techniques, such as vapor based techniques, wet chemical methods and spray pyrolysis are frequently employed to develop adherent CdS films. In the present study, rapid deposition of CdS thin films via plasma spray route using a solution precursor was investigated, for the first time. Solution precursor comprising cadmium chloride, thiourea and distilled water was fed into a DC plasma jet via an axial atomizer to create ultrafine droplets for instantaneous and accelerated thermal decomposition in the plasma plume. The resulting molten/semi-molten ultrafine/nanoparticles of CdS eventually propel toward the substrate to form continuous CdS films. The chemistry of the solution precursor was found to be critical in plasma pyrolysis to control the stoichiometry and composition of the films. X-ray diffraction studies confirmed hexagonal α-CdS structure. Surface morphology and microstructures were investigated to compare with other synthesis techniques in terms of process mechanism and structural features. Transmission electron microscopy studies revealed nanostructures in the atomized particulates. Optical measurements indicated a decreasing transmittance in the visible light with increasing the film thickness and band gap was calculated to be ∼2.5 eV. The electrical resistivity of the films (0.243 ± 0.188 × 10 5 Ω cm) was comparable with the literature values. These nanostructured polycrystalline CdS films could be useful in sensing and solar applications.

  16. Solution precursor plasma deposition of nanostructured CdS thin films

    Energy Technology Data Exchange (ETDEWEB)

    Tummala, Raghavender [Department of Mechanical Engineering, University of Michigan, Dearborn, MI 48128 (United States); Guduru, Ramesh K., E-mail: rkguduru@umich.edu [Department of Mechanical Engineering, University of Michigan, Dearborn, MI 48128 (United States); Mohanty, Pravansu S. [Department of Mechanical Engineering, University of Michigan, Dearborn, MI 48128 (United States)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer Inexpensive process with capability to produce large scale nanostructured coatings. Black-Right-Pointing-Pointer Technique can be employed to spray the coatings on any kind of substrates including polymers. Black-Right-Pointing-Pointer The CdS coatings developed have good electrical conductivity and optical properties. Black-Right-Pointing-Pointer Coatings possess large amount of particulate boundaries and nanostructured grains. -- Abstract: Cadmium sulfide (CdS) films are used in solar cells, sensors and microelectronics. A variety of techniques, such as vapor based techniques, wet chemical methods and spray pyrolysis are frequently employed to develop adherent CdS films. In the present study, rapid deposition of CdS thin films via plasma spray route using a solution precursor was investigated, for the first time. Solution precursor comprising cadmium chloride, thiourea and distilled water was fed into a DC plasma jet via an axial atomizer to create ultrafine droplets for instantaneous and accelerated thermal decomposition in the plasma plume. The resulting molten/semi-molten ultrafine/nanoparticles of CdS eventually propel toward the substrate to form continuous CdS films. The chemistry of the solution precursor was found to be critical in plasma pyrolysis to control the stoichiometry and composition of the films. X-ray diffraction studies confirmed hexagonal {alpha}-CdS structure. Surface morphology and microstructures were investigated to compare with other synthesis techniques in terms of process mechanism and structural features. Transmission electron microscopy studies revealed nanostructures in the atomized particulates. Optical measurements indicated a decreasing transmittance in the visible light with increasing the film thickness and band gap was calculated to be {approx}2.5 eV. The electrical resistivity of the films (0.243 {+-} 0.188 Multiplication-Sign 10{sup 5} {Omega} cm) was comparable with the literature

  17. Raman spectroscopy of optical properties in CdS thin films

    Directory of Open Access Journals (Sweden)

    Trajić J.

    2015-01-01

    Full Text Available Properties of CdS thin films were investigated applying atomic force microscopy (AFM and Raman spectroscopy. CdS thin films were prepared by using thermal evaporation technique under base pressure 2 x 10-5 torr. The quality of these films was investigated by AFM spectroscopy. We apply Raman scattering to investigate optical properties of CdS thin films, and reveal existence of surface optical phonon (SOP mode at 297 cm-1. Effective permittivity of mixture were modeled by Maxwell - Garnet approximation. [Projekat Ministarstva nauke Republike Srbije, br. 45003

  18. An alternative route towards monodisperse CdS quantum dots for hybrid solar cells

    International Nuclear Information System (INIS)

    Cao, Fengfeng; Wang, Hao; Xia, Zhouhui; Dai, Xiao; Cong, Shan; Dong, Chao; Sun, Baoquan; Lou, Yanhui; Sun, Yinghui; Zhao, Jie; Zou, Guifu

    2015-01-01

    Monodisperse CdS quantum dots (QDs) are synthesized by thermal decomposition of organic complexes in the system of the cost-effective commercial 0 # diesel at 200 °C. The prepared CdS QDs have a good dispersion and high crystallization. When the CdS QDs are doped into the blends of poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6, 6)C61 (PCBM) for hybrid solar cells (HSCs), the HSCs achieve about 25% increase of power conversion efficiency in comparison to the reference device without the CdS QDs. The improvement of the cell performance mainly attributes to the increased short-circuit current density arising from the absorption enhancement in the wavelength range of 350–550 nm by introducing the synthesized CdS QDs into the P3HT: PCBM active layer. - Highlights: • Monodisperse CdS quantum dots. • A cost-effective route to synthesize crystalline CdS quantum dots. • CdS quantum dots based hybrid solar cells with power conversion efficiency enhancement

  19. An alternative route towards monodisperse CdS quantum dots for hybrid solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Fengfeng; Wang, Hao [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Xia, Zhouhui [Institute of Functional Nano and Soft Materials, Soochow University, Suzhou 215123 (China); Dai, Xiao; Cong, Shan [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Dong, Chao [Department of Chemistry and Biology, University of New Mexico, ABQ 87120 (United States); Sun, Baoquan [Institute of Functional Nano and Soft Materials, Soochow University, Suzhou 215123 (China); Lou, Yanhui, E-mail: yhlou@suda.edu.cn [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Sun, Yinghui; Zhao, Jie [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China); Zou, Guifu, E-mail: zouguifu@suda.edu.cn [College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006 (China)

    2015-01-15

    Monodisperse CdS quantum dots (QDs) are synthesized by thermal decomposition of organic complexes in the system of the cost-effective commercial 0{sup #} diesel at 200 °C. The prepared CdS QDs have a good dispersion and high crystallization. When the CdS QDs are doped into the blends of poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6, 6)C61 (PCBM) for hybrid solar cells (HSCs), the HSCs achieve about 25% increase of power conversion efficiency in comparison to the reference device without the CdS QDs. The improvement of the cell performance mainly attributes to the increased short-circuit current density arising from the absorption enhancement in the wavelength range of 350–550 nm by introducing the synthesized CdS QDs into the P3HT: PCBM active layer. - Highlights: • Monodisperse CdS quantum dots. • A cost-effective route to synthesize crystalline CdS quantum dots. • CdS quantum dots based hybrid solar cells with power conversion efficiency enhancement.

  20. CdS thin films prepared by laser assisted chemical bath deposition

    International Nuclear Information System (INIS)

    Garcia, L.V.; Mendivil, M.I.; Garcia Guillen, G.; Aguilar Martinez, J.A.; Krishnan, B.; Avellaneda, D.; Castillo, G.A.; Das Roy, T.K.; Shaji, S.

    2015-01-01

    Highlights: • CdS thin films by conventional CBD and laser assisted CBD. • Characterized these films using XRD, XPS, AFM, optical and electrical measurements. • Accelerated growth was observed in the laser assisted CBD process. • Improved dark conductivity and good photocurrent response for the LACBD CdS. - Abstract: In this work, we report the preparation and characterization of CdS thin films by laser assisted chemical bath deposition (LACBD). CdS thin films were prepared from a chemical bath containing cadmium chloride, triethanolamine, ammonium hydroxide and thiourea under various deposition conditions. The thin films were deposited by in situ irradiation of the bath using a continuous laser of wavelength 532 nm, varying the power density. The thin films obtained during deposition of 10, 20 and 30 min were analyzed. The changes in morphology, structure, composition, optical and electrical properties of the CdS thin films due to in situ irradiation of the bath were analyzed by atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis spectroscopy. The thin films obtained by LACBD were nanocrystalline, photoconductive and presented interesting morphologies. The results showed that LACBD is an effective synthesis technique to obtain nanocrystalline CdS thin films having good optoelectronic properties

  1. CdS thin films prepared by laser assisted chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, L.V.; Mendivil, M.I.; Garcia Guillen, G.; Aguilar Martinez, J.A. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); Krishnan, B. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); CIIDIT – Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); Avellaneda, D.; Castillo, G.A.; Das Roy, T.K. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); Shaji, S., E-mail: sshajis@yahoo.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon 66450 (Mexico); CIIDIT – Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico)

    2015-05-01

    Highlights: • CdS thin films by conventional CBD and laser assisted CBD. • Characterized these films using XRD, XPS, AFM, optical and electrical measurements. • Accelerated growth was observed in the laser assisted CBD process. • Improved dark conductivity and good photocurrent response for the LACBD CdS. - Abstract: In this work, we report the preparation and characterization of CdS thin films by laser assisted chemical bath deposition (LACBD). CdS thin films were prepared from a chemical bath containing cadmium chloride, triethanolamine, ammonium hydroxide and thiourea under various deposition conditions. The thin films were deposited by in situ irradiation of the bath using a continuous laser of wavelength 532 nm, varying the power density. The thin films obtained during deposition of 10, 20 and 30 min were analyzed. The changes in morphology, structure, composition, optical and electrical properties of the CdS thin films due to in situ irradiation of the bath were analyzed by atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis spectroscopy. The thin films obtained by LACBD were nanocrystalline, photoconductive and presented interesting morphologies. The results showed that LACBD is an effective synthesis technique to obtain nanocrystalline CdS thin films having good optoelectronic properties.

  2. GenBank blastx search result: AK058464 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058464 001-016-A10 U27202.1 Actinobacillus pleuropneumoniae riboflavin biosynthesis operon, riboflavin...-specific deaminase (ribG), riboflavin synthase alpha subunit (ribB), bifunctional GTP ...cyclohydrase II/3,4-dihydroxy-2-butanone-4-phosphate synthase (ribA), and riboflavin synthase beta subunit (ribH) genes, complete cds.|BCT BCT 1e-105 +2 ...

  3. GenBank blastx search result: AK061948 [KOME

    Lifescience Database Archive (English)

    Full Text Available droxybutyrate biosynthetic beta-ketothiolase (phbA), and PHB synthase (phbC) genes, complete cds.|BCT BCT 1e-56 +3 ... ...AK061948 001-042-E07 AF267243.2 Azotobacter vinelandii PhbF (phbF), putative phasin protein PhbP (phbP), putative transcription activator PhbR (phb...R), acetoacetyl-CoA reductase (phbB), polyhy

  4. GenBank blastx search result: AK059654 [KOME

    Lifescience Database Archive (English)

    Full Text Available droxybutyrate biosynthetic beta-ketothiolase (phbA), and PHB synthase (phbC) genes, complete cds.|BCT BCT 3e-82 +1 ... ...AK059654 001-031-C10 AF267243.2 Azotobacter vinelandii PhbF (phbF), putative phasin protein PhbP (phb...P), putative transcription activator PhbR (phbR), acetoacetyl-CoA reductase (phbB), polyhy

  5. Synthesis of CdS Nanocrystals with Different Shapes via a Colloidal Method

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Jie; Liu, Changsong; Niu, Jinzhong; Wang, Hongzhe; Xu, Shasha; Shen, Huaibin; Li, Lin Song [Henan Univ., Henan (China)

    2014-02-15

    Size- and shape-controlled monodisperse wurtzite structured CdS nanorods have been successfully synthesized using a facile solution-based colloidal method. Depending on the control of injection/growth temperatures and the variation of Cd-to-S molar ratios, the morphology of the CdS nanocrystals (NCs) can be adjusted into bullet-like, rod-like, and dot-like shapes. X-ray diffraction (XRD), transition electron microscopy (TEM), and absorption spectroscopy were used to characterize the structure, morphology, and optical properties of as-synthesized CdS NCs. It was found that uniform CdS nanorods could be successfully synthesized when the injection and growth temperatures were very high (> 360 .deg. C). The aspect ratios of different shaped (bullet-like or rod-like) CdS NCs could be controlled by simply adjusting the molar ratios between Cd and S.

  6. Synthesis of CdS Nanocrystals with Different Shapes via a Colloidal Method

    International Nuclear Information System (INIS)

    Bai, Jie; Liu, Changsong; Niu, Jinzhong; Wang, Hongzhe; Xu, Shasha; Shen, Huaibin; Li, Lin Song

    2014-01-01

    Size- and shape-controlled monodisperse wurtzite structured CdS nanorods have been successfully synthesized using a facile solution-based colloidal method. Depending on the control of injection/growth temperatures and the variation of Cd-to-S molar ratios, the morphology of the CdS nanocrystals (NCs) can be adjusted into bullet-like, rod-like, and dot-like shapes. X-ray diffraction (XRD), transition electron microscopy (TEM), and absorption spectroscopy were used to characterize the structure, morphology, and optical properties of as-synthesized CdS NCs. It was found that uniform CdS nanorods could be successfully synthesized when the injection and growth temperatures were very high (> 360 .deg. C). The aspect ratios of different shaped (bullet-like or rod-like) CdS NCs could be controlled by simply adjusting the molar ratios between Cd and S

  7. Effects of precursors on the crystal structure and photoluminescence of CdS nanocrystalline

    International Nuclear Information System (INIS)

    Fu Zuoling; Zhou Shihong; Shi Jinsheng; Zhang Siyuan

    2005-01-01

    A series of cadmium sulfide (CdS) nanocrystalline were synthesized by precipitation from a mixture of aqueous solutions of cadmium salts and sulfur salts without adding any surface-termination agent. Their crystal structures and particle sizes were determined by X-ray diffraction (XRD). The CdS nanocrystalline precipitated from different precursors exhibited three cases: cubic phase, hexagonal phase and a hybrid of cubic and hexagonal phases. The photoluminescence (PL) of cadmium salt precursors and CdS nanocrystalline is also analyzed. Similar spectral band structure of cadmium salt precursors and CdS nanocrystalline is found. The PL of 3.4, 2.4 and 2.0 nm sized CdS nanocrystalline with the same crystal structure indicated quantum confinement effect

  8. Hexagonal pencil-like CdS nanorods: Facile synthesis and enhanced visible light photocatalytic performance

    Science.gov (United States)

    An, Liang; Wang, Guanghui; Zhao, Lei; Zhou, Yong; Gao, Fang; Cheng, Yang

    2015-07-01

    In the present study, hexagonal pencil-like CdS nanorods have been successfully synthesized through a typical facile and economical one-step hydrothermal method without using any surfactant or template. The product was characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and energy dispersive analysis of X-ray (EDX). The results revealed that the prepared CdS photocatalyst consisted of a large quantity of straight and smooth solid hexagonal nanorods and a few nanoparticles. The photocatalytic activities of CdS nanorods and commercial CdS powders were investigated by the photodegradation of Orange II (OII) in aqueous solution under visible light, and the CdS nanorods presented the highest photocatalytic activity. Its photocatalytic efficiency enhancement was attributed to the improved transmission of photogenerated electron-hole pairs in the CdS nanostructures. The present findings may provide a facile approach to synthesize high efficient CdS photocatalysts.

  9. Clinical guideline representation in a CDS: a human information processing method.

    Science.gov (United States)

    Kilsdonk, Ellen; Riezebos, Rinke; Kremer, Leontien; Peute, Linda; Jaspers, Monique

    2012-01-01

    The Dutch Childhood Oncology Group (DCOG) has developed evidence-based guidelines for screening childhood cancer survivors for possible late complications of treatment. These paper-based guidelines appeared to not suit clinicians' information retrieval strategies; it was thus decided to communicate the guidelines through a Computerized Decision Support (CDS) tool. To ensure high usability of this tool, an analysis of clinicians' cognitive strategies in retrieving information from the paper-based guidelines was used as requirements elicitation method. An information processing model was developed through an analysis of think aloud protocols and used as input for the design of the CDS user interface. Usability analysis of the user interface showed that the navigational structure of the CDS tool fitted well with the clinicians' mental strategies employed in deciding on survivors screening protocols. Clinicians were more efficient and more complete in deciding on patient-tailored screening procedures when supported by the CDS tool than by the paper-based guideline booklet. The think-aloud method provided detailed insight into users' clinical work patterns that supported the design of a highly usable CDS system.

  10. GenBank blastx search result: AK058655 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058655 001-018-F07 L47838.1 Bacillus subtilis (clone YAC15-6B) ponA gene, yppBCDEFG genes, ypqAE genes..., yprAB genes, cotD gene, ypsABC genes, rnaP gene, yptA gene, ypuA gene, kduDI genes, kdgRKAT genes, ypwA gene, complete cds's.|BCT BCT 7e-20 +1 ...

  11. GenBank blastx search result: AK062166 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062166 001-046-B08 L47838.1 Bacillus subtilis (clone YAC15-6B) ponA gene, yppBCDEFG genes, ypqAE genes..., yprAB genes, cotD gene, ypsABC genes, rnaP gene, yptA gene, ypuA gene, kduDI genes, kdgRKAT genes, ypwA gene, complete cds's.|BCT BCT 2e-12 +1 ...

  12. GenBank blastx search result: AK060500 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060500 001-017-F08 L47838.1 Bacillus subtilis (clone YAC15-6B) ponA gene, yppBCDEFG genes, ypqAE genes..., yprAB genes, cotD gene, ypsABC genes, rnaP gene, yptA gene, ypuA gene, kduDI genes, kdgRKAT genes, ypwA gene, complete cds's.|BCT BCT 1e-18 +1 ...

  13. Chemically deposited TiO2/CdS bilayer system for ...

    Indian Academy of Sciences (India)

    FTO/TiO2/CdS bilayers system showed improved performance of PEC properties over individual ... form distribution of nanocrystalline CdS on TiO2 and this is unfavourable for the ... (TEA), the pH of the solution maintained at 12·0 by drop.

  14. In situ coating multiwalled carbon nanotubes with CdS nanoparticles

    International Nuclear Information System (INIS)

    Liu Yangqiao; Gao Lian

    2005-01-01

    CdS nanoparticles were homogeneously coated on multiwalled carbon nanotubes by an in situ method through introducing thiol groups onto the tube wall using a novel method. A cationic polyelectrolyte containing reactive imine groups, polyethyleneimine (PEI), was firstly adsorbed on the surface of nanotubes. 3-Mercaptopropionic acid (MPA) was then anchored by an amidation reaction between its carboxyl group and the imine group of the polyelectrolyte under the activation of carbodiimide reagents. These -SH terminated MWCNTs were coated with CdS nanoparticles by an in situ method. The phase composition, microstructure, and the UV-vis properties of the CdS coated MWCNTs were characterized. The addition of the carbodiimide reagents played an important role in linking the MPA with PEI covalently and subsequently coating the MWCNTs with CdS homogeneously. A blue shift in the absorption edge was observed for the MWCNTs-CdS hybrid material due to the quantum size effect

  15. Nanoniobia modification of CdS photoanode for an efficient and stable photoelectrochemical cell.

    Science.gov (United States)

    Pareek, Alka; Paik, Pradip; Borse, Pramod H

    2014-12-30

    Herein we report the surface modification of a CdS film by niobia nanoparticles via thioglycerol as an organic linker and thus fabricate an efficient and a stable photoanode for a photoelectrochemical (PEC) cell. We have synthesized three differenly sized (∼3, ∼6 ,and ∼9 nm) niobia nanoparticles by a hydrothermal synthesis approach and have further investigated the particle-size-dependent PEC performance of the nanoparticle-modified CdS photoanode. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) confirm the formation of Nb2O5 nanoparticles that are prepared via decomposition of the niobium peroxo complex during the hydrothermal reaction and reveal the presence of surface OH(-) groups over niobia nanoparticles that impart a high catalytic property to a material. The nano-Nb2O5-modified photoanode displayed a 23-fold higher power conversion efficiency compared to that of CdS. This modified structure increases the open circuit voltage (OCV) from 0.65 to 0.77 V, which is attributed to the nano-Nb2O5-induced surface passivation effect over bare CdS. Linking of nanoparticles on the CdS surface improves the photocorrosion stability of the CdS photoanode for even longer than 4 h in contrast to the tens of minutes for the base CdS surface. The uniform coverage of the CdS photoanode surface by niobia nanoparticles is thus found to be the controlling parameter for achieving a higher PEC performance and stability of the photoanode. This finding directed us to design an improved CdS photoanode for efficient and prolonged PEC hydrogen generation from a PEC cell.

  16. CdS films deposited by chemical bath under rotation

    International Nuclear Information System (INIS)

    Oliva-Aviles, A.I.; Patino, R.; Oliva, A.I.

    2010-01-01

    Cadmium sulfide (CdS) films were deposited on rotating substrates by the chemical bath technique. The effects of the rotation speed on the morphological, optical, and structural properties of the films were discussed. A rotating substrate-holder was fabricated such that substrates can be taken out from the bath during the deposition. CdS films were deposited at different deposition times (10, 20, 30, 40 and 50 min) onto Corning glass substrates at different rotation velocities (150, 300, 450, and 600 rpm) during chemical deposition. The chemical bath was composed by CdCl 2 , KOH, NH 4 NO 3 and CS(NH 2 ) 2 as chemical reagents and heated at 75 deg. C. The results show no critical effects on the band gap energy and the surface roughness of the CdS films when the rotation speed changes. However, a linear increase on the deposition rate with the rotation energy was observed, meanwhile the stoichiometry was strongly affected by the rotation speed, resulting a better 1:1 Cd/S ratio as speed increases. Rotation effects may be of interest in industrial production of CdTe/CdS solar cells.

  17. CdS films deposited by chemical bath under rotation

    Energy Technology Data Exchange (ETDEWEB)

    Oliva-Aviles, A.I., E-mail: aoliva@mda.cinvestav.mx [Centro de Investigacion y de Estudios Avanzados Unidad Merida, Departamento de Fisica Aplicada. A.P. 73-Cordemex, 97310 Merida, Yucatan (Mexico); Patino, R.; Oliva, A.I. [Centro de Investigacion y de Estudios Avanzados Unidad Merida, Departamento de Fisica Aplicada. A.P. 73-Cordemex, 97310 Merida, Yucatan (Mexico)

    2010-08-01

    Cadmium sulfide (CdS) films were deposited on rotating substrates by the chemical bath technique. The effects of the rotation speed on the morphological, optical, and structural properties of the films were discussed. A rotating substrate-holder was fabricated such that substrates can be taken out from the bath during the deposition. CdS films were deposited at different deposition times (10, 20, 30, 40 and 50 min) onto Corning glass substrates at different rotation velocities (150, 300, 450, and 600 rpm) during chemical deposition. The chemical bath was composed by CdCl{sub 2}, KOH, NH{sub 4}NO{sub 3} and CS(NH{sub 2}){sub 2} as chemical reagents and heated at 75 deg. C. The results show no critical effects on the band gap energy and the surface roughness of the CdS films when the rotation speed changes. However, a linear increase on the deposition rate with the rotation energy was observed, meanwhile the stoichiometry was strongly affected by the rotation speed, resulting a better 1:1 Cd/S ratio as speed increases. Rotation effects may be of interest in industrial production of CdTe/CdS solar cells.

  18. Toxicity of cadmium sulfide (CdS) nanoparticles against Escherichia coli and HeLa cells

    International Nuclear Information System (INIS)

    Hossain, Sk Tofajjen; Mukherjee, Samir Kumar

    2013-01-01

    Highlights: • Toxic effect of CdS NPs on the growth and cell division in E. coli was studied. • CdS NPs affected cell surface topology and cell division. • Downregulation of both FtsZ and FtsQ was observed due to NPs exposure. • CdS NPs affected HeLa cell morphology with fragmented nuclei. • All such effects might be due to elevated oxidative stress. -- Abstract: The present study endeavours to assess the toxic effect of synthesized CdS nanoparticles (NPs) on Escherichia coli and HeLa cells. The CdS NPs were characterized by DLS, XRD, TEM and AFM studies and the average size of NPs was revealed as ∼3 nm. On CdS NPs exposure bacterial cells changed morphological features to filamentous form and damage of the cell surface was found by AFM study. The expression of two conserved cell division components namely ftsZ and ftsQ in E. coli was decreased both at transcriptional and translational levels upon CdS NPs exposure. CdS NPs inhibited proper cell septum formation without affecting the nucleoid segregation. Viability of HeLa cells declined with increasing concentration of CdS NPs and the IC 50 value was found to be 4 μg/mL. NPs treated HeLa cells showed changed morphology with condensed and fragmented nuclei. Increased level of reactive oxygen species (ROS) was found both in E. coli and HeLa cells on CdS NPs exposure. The inverse correlation between declined cell viabilities and elevated ROS level suggested that oxidative stress seems to be the key event by which NPs induce toxicity both in E. coli and HeLa cells

  19. Anodic Titania Nanotube Arrays Sensitized with Mn- or Co-Doped CdS Nanocrystals

    International Nuclear Information System (INIS)

    Smith, York R.; Gakhar, Ruchi; Merwin, Augustus; Mohanty, Swomitra K.; Chidambaram, Dev; Misra, Mano

    2014-01-01

    Highlights: • Mn or Co doped CdS where synthesized and deposited onto TiO 2 nanotubular arrays. • Synthesis and deposition were achieved simultaneously using SILAR method. • Various characterization techniques demonstrate lattice incorporation of dopant. • Photoelectrochemical performance was analyzed using AM 1.5 irradiation. • Dopants increases depletion width of CdS and increase photoelectrochemical responses. - Abstract: The use of doped luminescent nanocrystals or quantum dots have mainly been explored for imaging applications; however, recently they have gained interest in solar energy conversion applications due to long electron lifetimes, tunable band gaps and emission by compositional control. In this study, we have examined the application of Mn or Co doped CdS nanocrystals as a sensitizing layer over titania nanotubular arrays synthesized via electrochemical anodization in photoelectrochemical applications. The doped and undoped CdS nanocrystals were simultaneously synthesized and deposited onto the titania surface by adoption of a successive ion layer adsorption-reaction (SILAR) method. Various characterization methods indicate lattice incorporation of the dopant within CdS. The addition of dopants to CdS was found to improve the photoelectrochemical performance by increasing the depletion width of the CdS nanocrystals and reducing recombination losses of charge carriers

  20. New session of “CERN Document Server (CDS), Inspire and Library Services”

    CERN Multimedia

    Technical Training

    2013-01-01

    The training course is given by members of CERN’s CDS Team (IT-CIS group) and the Library Services (GIS SIS group) and is intended for all CERN members of personnel.   This course will present CDS, inspirehep.net, and the content, scope and scientific information available in or with CDS, as well as the classification and organisation of the documents. It is intended to give you the training to use CDS efficiently and, in particular, covers:
 the main characteristics and advanced features for the search of documents (scientific, multimedia, etc)
, the collaborative tools: baskets, alerts, comments, evaluation, etc.
 the submission of documents in CDS and examples of workflows.   An important part of the training will be the various exercises, designed to give participants the ability to work with CDS in real life cases, including with the most advanced features. Don’t wait! Sign up for the training course directly through the CERN Training Catal...

  1. Mesoporous structured MIPs@CDs fluorescence sensor for highly sensitive detection of TNT.

    Science.gov (United States)

    Xu, Shoufang; Lu, Hongzhi

    2016-11-15

    A facile strategy was developed to prepare mesoporous structured molecularly imprinted polymers capped carbon dots (M-MIPs@CDs) fluorescence sensor for highly sensitive and selective determination of TNT. The strategy using amino-CDs directly as "functional monomer" for imprinting simplify the imprinting process and provide well recognition sites accessibility. The as-prepared M-MIPs@CDs sensor, using periodic mesoporous silica as imprinting matrix, and amino-CDs directly as "functional monomer", exhibited excellent selectivity and sensitivity toward TNT with detection limit of 17nM. The recycling process was sustainable for 10 times without obvious efficiency decrease. The feasibility of the developed method in real samples was successfully evaluated through the analysis of TNT in soil and water samples with satisfactory recoveries of 88.6-95.7%. The method proposed in this work was proved to be a convenient and practical way to prepare high sensitive and selective fluorescence MIPs@CDs sensors. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Single-Source Molecular Precursor for Synthesis of CdS Nanoparticles and Nanoflowers

    Science.gov (United States)

    Salavati-Niasari, Masoud; Sobhani, Azam

    2012-04-01

    CdS Semiconductor nanostructures were synthesized by using two different methods. Using triphenylphosphine (C18H15P) and oleylamine (C18H37N) as surfactant, CdS semiconductor nanocrystals with a size ranging from 30 to 90 nm can be synthesized by thermal decomposition of precursor [bis(thiosemicarbazide)cadmium(II)]. CdS nanoflowers were synthesized via hydrothermal decomposition of [bis(thiosemicarbazide) cadmium(II)] without any surfactant. X-ray diffraction (XRD) patterns confirm that the resulting samples were a pure hexagonal phase of CdS. The optical property test indicates that the absorption peak of the samples shifts towards short wavelength, and the blue shift phenomenon might be ascribed to the quantum effect.

  3. Fullerene (C{sub 60})/CdS nanocomposite with enhanced photocatalytic activity and stability

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Qiang [Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education, School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Hu, Zhuofeng, E-mail: st04hzhf@gmail.com [Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong (China); Zhang, Qian; Li, Boyuan [Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education, School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Shen, Zhurui, E-mail: shenzhurui@tju.edu.cn [Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education, School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China)

    2017-05-01

    Highlights: • C{sub 60}/CdS nanocomposite has been fabricated as a novel visible-light-driven photocatalyst. • It exhibits enhanced photocatalytic activity and photostability than that of pure CdS reference. • The C{sub 60} improved the charge separation and transfer of nanocomposite due to its high electron affinity. - Abstract: Herein, the fullerene (C{sub 60})/CdS nanocomposite has been fabricated by a facile one-pot hydrothermal method. Its photocatatlytic hydrogen (H{sub 2}) evolution rate and degradation efficiency of Rhodamine B (Rh B) are evaluated under visible light irradiation (λ ≥ 420 nm). The content of C{sub 60} has been changed from 0.4 wt% to 8 wt%, and the optimal value for photocatalytic activity is determined to be 0.4 wt%. The H{sub 2} evolution rate over this optimal sample reaches 1.73 mmol h{sup −1} g{sup −1} and its apparent degradation rate of Rh B is 0.089 min{sup −1} (degradation efficiency of 97% within 40 min), which is 2.3 times and 1.5 times compared to that of pure CdS reference. Moreover, the photocorrosion of CdS in composite is effectively suppressed, and its photocatalytic activity can be well maintained after three recycles (97.8% retaining for composite vs. 84.4% retaining for CdS). Then, the enhanced photocatalytic activity and stability of C{sub 60}/CdS nanocomposite are further studied by spectroscopic and electrochemical methods. Results show that the C{sub 60} species covering on the surface of CdS can efficiently accelerate the separation and transfer of photoexcited charge carriers, which can improve its activity, and reduce the photocorrosion of CdS.

  4. Simulation of sovereign CDS market based on interaction between market participant

    Science.gov (United States)

    Ko, Bonggyun; Kim, Kyungwon

    2017-08-01

    A research for distributional property of financial asset is the subject of intense interest not only for financial theory but also for practitioner. Such respect is no exception to CDS market. The CDS market, which began to receive attention since the global financial debacle, is not well researched despite of the importance of research necessity. This research introduces creation of CDS market and use Ising system utilizing occurrence characteristics (to shift risk) as an important factor. Therefore the results of this paper would be of great assistance to both financial theory and practice. From this study, not only distributional property of the CDS market but also various statistics like multifractal characteristics could promote understanding about the market. A salient point in this study is that countries are mainly clustering into 2 groups and it might be because of market situation and geographical characteristics of each country. This paper suggested 2 simulation parameters representing this market based on understanding such CDS market situation. The estimated parameters are suitable for high and low risk event of CDS market respectively and these two parameters are complementary and can cover not only basic statistics but also multifractal properties of most countries. Therefore these estimated parameters can be used in researches preparing for a certain event (high or low risk). Finally this research will serve as a momentum double-checking indirectly the performance of Ising system based on these results.

  5. The effect of different pH modifier on formation of CdS nanoparticles

    International Nuclear Information System (INIS)

    Ren Xiaoxiao; Zhao Gaoling; Li Hong; Wu Wei; Han Gaorong

    2008-01-01

    CdS nanoparticles were prepared by hydrothermal method. The effects of pH modifier on the properties of CdS particles were studied. NaOH and NH 4 OH were chosen as the pH modifier. The morphology and optical properties of CdS particles were characterized by transmitted electron microscope (TEM) and optical absorption spectra analysis, respectively. The particle size of the samples whose pH modifier is NaOH was smaller than that of the CdS samples with NH 4 OH at the same pH value. Optical absorption edge of CdS shifted to longer wavelength with increasing pH value. Optical absorption edge of the samples with NH 4 OH as pH modifier shifted to the longer wavelength more significantly than that of those samples with NaOH as pH modifier. When CdS particles were adsorbed to the TiO 2 electrodes, the photoelectrochemical property of CdS-sensitized TiO 2 electrode showed that the samples with NH 4 OH as pH modifier had higher photocurrent than those samples with NaOH

  6. Complete Mitochondrial Genomes of the Cherskii's Sculpin Cottus czerskii and Siberian Taimen Hucho taimen Reveal GenBank Entry Errors: Incorrect Species Identification and Recombinant Mitochondrial Genome.

    Science.gov (United States)

    Balakirev, Evgeniy S; Saveliev, Pavel A; Ayala, Francisco J

    2017-01-01

    The complete mitochondrial (mt) genome is sequenced in 2 individuals of the Cherskii's sculpin Cottus czerskii . A surprisingly high level of sequence divergence (10.3%) has been detected between the 2 genomes of C czerskii studied here and the GenBank mt genome of C czerskii (KJ956027). At the same time, a surprisingly low level of divergence (1.4%) has been detected between the GenBank C czerskii (KJ956027) and the Amur sculpin Cottus szanaga (KX762049, KX762050). We argue that the observed discrepancies are due to incorrect taxonomic identification so that the GenBank accession number KJ956027 represents actually the mt genome of C szanaga erroneously identified as C czerskii . Our results are of consequence concerning the GenBank database quality, highlighting the potential negative consequences of entry errors, which once they are introduced tend to be propagated among databases and subsequent publications. We illustrate the premise with the data on recombinant mt genome of the Siberian taimen Hucho taimen (NCBI Reference Sequence Database NC_016426.1; GenBank accession number HQ897271.1), bearing 2 introgressed fragments (≈0.9 kb [kilobase]) from 2 lenok subspecies, Brachymystax lenok and Brachymystax lenok tsinlingensis , submitted to GenBank on June 12, 2011. Since the time of submission, the H taimen recombinant mt genome leading to incorrect phylogenetic inferences was propagated in multiple subsequent publications despite the fact that nonrecombinant H taimen genomes were also available (submitted to GenBank on August 2, 2014; KJ711549, KJ711550). Other examples of recombinant sequences persisting in GenBank are also considered. A GenBank Entry Error Depositary is urgently needed to monitor and avoid a progressive accumulation of wrong biological information.

  7. Synthesis and photoluminescence properties of comb-like CdS nanobelt/ZnO nanorod heterostructures

    International Nuclear Information System (INIS)

    Lan Changyong; Gong Jiangfeng; Liu Chunming

    2012-01-01

    Highlights: ► Comb-like CdS nanobelt/ZnO nanorod heterostructures were synthesized. ► ZnO nanorods epitaxially grew on the (1 0 0) surface of the CdS nanobelts along [1 0 0]. ► A preliminary growth mechanism was proposed. - Abstract: Comb-like CdS nanobelt/ZnO nanorod heterostructures were synthesized by a two-stage method. X-ray diffractometer, scanning electron microscopy, transmission electron microscopy were used to characterize and analyze the as-synthesized products. The results demonstrate that the CdS nanobelt backbones grow along [2 1 0] and the ZnO nanorod branches epitaxially grow on the (0 0 1) surface of the CdS nanobelt with a growth direction of [0 0 1]. The as-prepared heterostructures exhibit an important feature of single-crystallinity. At room temperature, the comb-like CdS nanobelt/ZnO nanorod heterostructures show strong green emission.

  8. Optimal Financing with CDS Markets

    NARCIS (Netherlands)

    Matta, R.

    2013-01-01

    One could argue that CDSs improve risk sharing, hence credit supply and financing terms for firms. Accordingly, one would expect risky borrowers to benefit the most from CDS insurance. This is in contrast, however, with recent empirical evidence (Ashcraft and Santos (2009) and Hirtle (2009)). This

  9. GenBank blastx search result: AK104368 [KOME

    Lifescience Database Archive (English)

    Full Text Available ase accessory protein D (ureD), urease structural subunit A (ureA), urease accessory protein J (ureJ), ureas...e structural subunits B (ureB) and C (ureC), urease accessory proteins EF (ureEF) and G (ureG) genes, complete cds.|BCT BCT 9e-57 +1 ... ...AK104368 001-035-E04 AF000579.1 Bordetella bronchiseptica LysR transcriptional activator homolog (bbuR), ure

  10. GenBank blastx search result: AK104368 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104368 001-035-E04 AF056189.1 Synechococcus WH7805 urease accessory protein UreG (ureG), urease... accessory protein UreF (ureF), urease accessory protein UreE (ureE), urease accessory protein UreD (ureD), urease... gamma subunit (ureA), urease beta subunit (ureB), and urease alpha subunit (ureC) genes, complete cds.|BCT BCT 1e-59 +1 ...

  11. GenBank blastx search result: AK104200 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104200 006-304-B01 AF056189.1 Synechococcus WH7805 urease accessory protein UreG (ureG), urease... accessory protein UreF (ureF), urease accessory protein UreE (ureE), urease accessory protein UreD (ureD), urease... gamma subunit (ureA), urease beta subunit (ureB), and urease alpha subunit (ureC) genes, complete cds.|BCT BCT 1e-59 +1 ...

  12. Development of a Higher Fidelity Model for the Cascade Distillation Subsystem (CDS)

    Science.gov (United States)

    Perry, Bruce; Anderson, Molly

    2014-01-01

    Significant improvements have been made to the ACM model of the CDS, enabling accurate predictions of dynamic operations with fewer assumptions. The model has been utilized to predict how CDS performance would be impacted by changing operating parameters, revealing performance trade-offs and possibilities for improvement. CDS efficiency is driven by the THP coefficient of performance, which in turn is dependent on heat transfer within the system. Based on the remaining limitations of the simulation, priorities for further model development include: center dot Relaxing the assumption of total condensation center dot Incorporating dynamic simulation capability for the buildup of dissolved inert gasses in condensers center dot Examining CDS operation with more complex feeds center dot Extending heat transfer analysis to all surfaces

  13. Magnetodielectric effect in CdS nanosheets grown within Na-4 mica

    Science.gov (United States)

    Mandal, Amrita; Mitra, Sreemanta; Datta, Anindya; Banerjee, Sourish; Chakravorty, Dipankar

    2012-04-01

    CdS nanosheets of thickness 0.6 nm were grown within the interlayer spaces of Na-4 mica. Magnetization measurements carried out in the temperature range 2-300 K showed the composites to have weak ferromagnetic-like properties even at room temperature. The saturation magnetization (MS) at room temperature was found to be higher than that reported for CdS nanoparticles. The higher value of MS may be ascribed to the presence of a large number defects in the present CdS system, due to a large surface to volume ratio in the nanosheets as compared to that of CdS nanoparticles. The nanocomposites exhibited a magnetodielectric effect with a dielectric constant change of 5.3% for a magnetic field of 0.5 T. This occurred due to a combination of magnetoresistance and Maxwell-Wagner effect as delineated in the model developed by Catalan.

  14. Optical sensor based on a single CdS nanobelt.

    Science.gov (United States)

    Li, Lei; Yang, Shuming; Han, Feng; Wang, Liangjun; Zhang, Xiaotong; Jiang, Zhuangde; Pan, Anlian

    2014-04-23

    In this paper, an optical sensor based on a cadmium sulfide (CdS) nanobelt has been developed. The CdS nanobelt was synthesized by the vapor phase transportation (VPT) method. X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) results revealed that the nanobelt had a hexagonal wurtzite structure of CdS and presented good crystal quality. A single nanobelt Schottky contact optical sensor was fabricated by the electron beam lithography (EBL) technique, and the device current-voltage results showed back-to-back Schottky diode characteristics. The photosensitivity, dark current and the decay time of the sensor were 4 × 10⁴, 31 ms and 0.2 pA, respectively. The high photosensitivity and the short decay time were because of the exponential dependence of photocurrent on the number of the surface charges and the configuration of the back to back Schottky junctions.

  15. Compton profiles and band structure calculations of CdS and CdTe

    International Nuclear Information System (INIS)

    Heda, N.L.; Mathur, S.; Ahuja, B.L.; Sharma, B.K.

    2007-01-01

    In this paper we present the isotropic Compton profiles of zinc-blende CdS and CdTe measured at an intermediate resolution of 0.39 a.u. using our 20 Ci 137 Cs Compton spectrometer. The electronic band structure calculations for both the zinc-blende structure compounds and also wurtzite CdS have been undertaken using various schemes of ab-initio linear combination of atomic orbitals calculations implemented in CRYSTAL03 code. The band structure and Mulliken's populations are reported using density functional scheme. In case of wurtzite CdS, our theoretical anisotropies in directional Compton profiles are compared with available experimental data. In case of both the zinc-blende compounds, the isotropic experimental profiles are found to be in better agreement with the present Hartree-Fock calculations. A study of the equal-valence-electron-density experimental profiles of zinc-blende CdS and CdTe shows that the CdS is more ionic than CdTe. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. The effect of different pH modifier on formation of CdS nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Xiaoxiao, Ren [State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Zhao Gaoling [State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China)], E-mail: glzhao@zju.edu.cn; Hong, Li; Wei, Wu; Gaorong, Han [State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China)

    2008-10-06

    CdS nanoparticles were prepared by hydrothermal method. The effects of pH modifier on the properties of CdS particles were studied. NaOH and NH{sub 4}OH were chosen as the pH modifier. The morphology and optical properties of CdS particles were characterized by transmitted electron microscope (TEM) and optical absorption spectra analysis, respectively. The particle size of the samples whose pH modifier is NaOH was smaller than that of the CdS samples with NH{sub 4}OH at the same pH value. Optical absorption edge of CdS shifted to longer wavelength with increasing pH value. Optical absorption edge of the samples with NH{sub 4}OH as pH modifier shifted to the longer wavelength more significantly than that of those samples with NaOH as pH modifier. When CdS particles were adsorbed to the TiO{sub 2} electrodes, the photoelectrochemical property of CdS-sensitized TiO{sub 2} electrode showed that the samples with NH{sub 4}OH as pH modifier had higher photocurrent than those samples with NaOH.

  17. Synthesis, optical, structural, and electrical properties of single-crystalline CdS nanobelts

    Energy Technology Data Exchange (ETDEWEB)

    Alqahtani, Mohammed S. [King Saud University, Department of Physics and Astronomy, Riyadh (Saudi Arabia); Hadia, N.M.A.; Mohamed, S.H. [Sohag University, Physics Department, Faculty of Science, Sohag (Egypt)

    2017-04-15

    CdS nanobelts (NBs) were synthesized by vapor transport of CdS powders. The growth was carried out without any catalyst on quartz and Si (100) substrates. The synthesized CdS NBs were examined by transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and selected area electron diffraction (SAED), high-resolution transmission electron microscopy (HR-TEM), X-ray powder diffraction (XRD), energy dispersion analysis of X-ray (EDAX), spectrophotometer, and photoluminescence spectroscopy. CdS NBs were indexed as hexagonal wurtzite structure. The growth was via vapor-solid growth mechanism and along the [100] direction. The refractive index was evaluated in the transparent region, as suggested by Swanepoel, using the envelope method. The refractive index values and the extinction coefficient were decreased by increasing the wavelength. The calculated optical band gap was 2.50 eV. The photoluminescence (PL) spectrum of the synthesized CdS NBs exhibited a green emission peak at 510 nm and a broad red emission peak at 696 nm. The conductivity measurements were achieved, in the temperature range from 300 to 600 K, using the conventional two-probe technique. Two different slopes with different activation energies of 0.618 and 0.215 eV were obtained. The CdS NBs are likely being novel functional materials. Thus, they can be used in the manufacture of innovative optoelectronic nanodevices. (orig.)

  18. Nano-architecture based photoelectrochemical water oxidation efficiency enhancement by CdS photoanodes

    Science.gov (United States)

    Pareek, Alka; Kim, Hyun Gyu; Paik, Pradip; Joardar, Joydip; Borse, Pramod H.

    2017-02-01

    In the present work, 2D nanostructuring has been utilized to impart an efficiency improvement to the hexagonal phase CdS films for the photoelectrochemical (PEC) cells those were deposited by spray pyrolysis technique. By controlling the aerosol droplet- size, population and impingement time during the spray pyrolysis deposition, various nano-features viz. randomly aligned nanorods, nanotubes and nanowires of CdS has been demonstrated for the first time. A growth mechanism has been proposed to predict the temporal evolution of the nanostructures. The prominent nanoscale structures show improved optical properties in the visible range of solar spectrum. The structural studies validate the morphological differences of nanostructures in terms of the texture coefficient analysis as well as 2D micro x-ray diffraction imaging. Electrochemical characterization is carried out to understand the effect of nanostructuring on the PEC performance of the CdS photoanodes in the sulphide (0.1 M Na2S  +  0.02 M Na2SO3) electrolyte at applied bias of 0.2 V (versus SCE). The evolution of morphology from randomly aligned rods to nanowire is responsible for improved photocurrent (3.5 times). CdS film morphology can be tuned to nanotubes, nano- rose buds and nanorod bunches even by doping Zn2+ ions in CdS lattice. Nano-structuring of doped CdS has shown enhanced performance of the photoanodes. The nanotubes structures yielded highest photocurrent density of 1.6 mA cm-2. Whereas modifying the 2D-nanostructured CdS film by simple MoO3 spray coating yields the photocurrent enhancement to 2.1 mA cm-2.

  19. White light emitting device based on single-phase CdS quantum dots

    Science.gov (United States)

    Li, Feng; Nie, Chao; You, Lai; Jin, Xiao; Zhang, Qin; Qin, Yuancheng; Zhao, Feng; Song, Yinglin; Chen, Zhongping; Li, Qinghua

    2018-05-01

    White light emitting diodes (WLEDs) based on quantum dots (QDs) are emerging as robust candidates for white light sources, however they are suffering from the problem of energy loss resulting from the re-absorption and self-absorption among the employed QDs of different peak wavelengths. It still remains a challenging task to construct WLEDs based on single-phase QD emitters. Here, CdS QDs with short synthesis times are introduced to the fabrication of WLEDs. With a short synthesis time, on one hand, CdS QDs with a small diameter with blue emission can be obtained. On the other hand, surface reconstruction barely has time to occur, and the surface is likely defect-ridden, which enables the existence of a broad emission covering the range of green, yellow and red regions. This is essential for the white light emission of CdS QDs, and is very important for WLED applications. The temporal evolution of the PL spectra for CdS QDs was obtained to investigate the influence of growth time on the luminescent properties. The CdS QDs with a growth time of 0.5 min exhibited a colour rendering index (CRI) of 79.5 and a correlated colour temperature (CCT) of 6238 K. With increasing reaction time, the colour coordinates of the CdS QDs will move away from the white light region in the CIE 1931 chromaticity diagram. By integrating the as prepared white light emission CdS QDs with a violet GaN chip, WLEDs were fabricated. The fabricated WLEDs exhibited a CRI of 87.9 and a CCT of 4619 K, which satisfy the demand of general illumination. The luminous flux and the luminous efficiency of the fabricated WLEDs, being less advanced than current commercial white light sources, can be further improved, meaning there is a need for much more in-depth studies on white light emission CdS QDs.

  20. Complete Mitochondrial Genomes of the Cherskii’s Sculpin Cottus czerskii and Siberian Taimen Hucho taimen Reveal GenBank Entry Errors: Incorrect Species Identification and Recombinant Mitochondrial Genome

    Science.gov (United States)

    Balakirev, Evgeniy S; Saveliev, Pavel A; Ayala, Francisco J

    2017-01-01

    The complete mitochondrial (mt) genome is sequenced in 2 individuals of the Cherskii’s sculpin Cottus czerskii. A surprisingly high level of sequence divergence (10.3%) has been detected between the 2 genomes of C czerskii studied here and the GenBank mt genome of C czerskii (KJ956027). At the same time, a surprisingly low level of divergence (1.4%) has been detected between the GenBank C czerskii (KJ956027) and the Amur sculpin Cottus szanaga (KX762049, KX762050). We argue that the observed discrepancies are due to incorrect taxonomic identification so that the GenBank accession number KJ956027 represents actually the mt genome of C szanaga erroneously identified as C czerskii. Our results are of consequence concerning the GenBank database quality, highlighting the potential negative consequences of entry errors, which once they are introduced tend to be propagated among databases and subsequent publications. We illustrate the premise with the data on recombinant mt genome of the Siberian taimen Hucho taimen (NCBI Reference Sequence Database NC_016426.1; GenBank accession number HQ897271.1), bearing 2 introgressed fragments (≈0.9 kb [kilobase]) from 2 lenok subspecies, Brachymystax lenok and Brachymystax lenok tsinlingensis, submitted to GenBank on June 12, 2011. Since the time of submission, the H taimen recombinant mt genome leading to incorrect phylogenetic inferences was propagated in multiple subsequent publications despite the fact that nonrecombinant H taimen genomes were also available (submitted to GenBank on August 2, 2014; KJ711549, KJ711550). Other examples of recombinant sequences persisting in GenBank are also considered. A GenBank Entry Error Depositary is urgently needed to monitor and avoid a progressive accumulation of wrong biological information. PMID:28890653

  1. Thermal and Optical Properties of CdS Nanoparticles in Thermotropic Liquid Crystal Monomers

    Directory of Open Access Journals (Sweden)

    Marc Alnot

    2010-03-01

    Full Text Available Two new mesogenic monomers, namely 3,3’-dimethoxy-4,4’-di(hydroxyhexoxy-N-benzylidene-o-Tolidine (Ia and 4,4’-di(6-hydroxyhexoxy-N-benzylidene-o-Tolidine (IIa, were reacted with cadmium sulfide (CdS via an in situ chemical precipitation method in ethanol to produce CdS nanocomposites. A series of different mass compositions of CdS with Ia and IIa ranging from 0.1:1.0 to 1.0:1.0 (w/w were prepared and characterized using X-ray Diffraction (XRD, Raman spectroscopy, Fourier Transform Infrared Spectroscopy (FT-IR, Transmission Electron Microscopy (TEM, Polarizing Optical Microscopy (POM and Differential Scanning Calorimetry (DSC, X-ray Photoelectron Spectroscopy (XPS and Photoluminescence Spectroscopy (PL. XRD showed that the broad peaks are ascribed to the formation of cubic CdS nanoparticles in both Ia and IIa. The average particle size for both nanocomposites was less than 5 nm with a narrower size distribution when compared with pure CdS nanoparticles. The analyses from POM and DSC demonstrated that mass composition from 0.1:1.0 up to 0.5:1.0 of CdS:Ia nanocomposites showed their enantiotropic nematic phase. On the other hand, polarizing optical microscopy (POM for IIa nanocomposites showed that the liquid crystal property vanished completely when the mass composition was at 0.2:1.0. PL emissions for CdS: Ia or IIa nanocomposites indicated deep trap defects occurred in these both samples. The PL results revealed that addition of CdS to Ia monomers suppressed the photoluminescence intensity of Ia. However, the introduction of CdS to IIa monomers increased the photoluminescence and was at a maximum when the mass composition was 0.3:1.0, then decreased in intensity as more CdS was added. The XPS results also showed that the stoichiometric ratios of S/Cd were close to 1.0:1.0 for both types of nanocomposites for a mass composition of 1.0:1.0 (CdS:matrix.

  2. Mixed-solvothermal synthesis of CdS micro/nanostructures and their optical properties

    International Nuclear Information System (INIS)

    Zhong Shengliang; Zhang Linfei; Huang Zhenzhong; Wang Shangping

    2011-01-01

    Several novel cadmium sulfide (CdS) micro/nanostructures, including cauliflower-like microspheres, football-like microspheres, tower-like microrods, and dendrites were controllably prepared via an oxalic acid-assisted solvothermal route using ethylene glycol (EG) and H 2 O as pure and mixed solvents with different S sources. The as-prepared products were characterized by X-ray powder diffraction (XRD), scanning electronic microscope (SEM) and UV-vis spectrophotometer (UV). It was found that CdS micro/nanostructures can be selectively obtained by varying the composition of solvent, concentration of oxalic acid, and sulfur sources. UV-vis absorption spectra reveal that their absorption properties are shape-dependent. The possible formation process of the CdS micro/nanostructures was briefly discussed. This route provides a facile way to tune the morphologies of CdS over a wide range.

  3. Rapid synthesis of triangular CdS nanocrystals without any trap emission

    International Nuclear Information System (INIS)

    Poulose, Aby Cheruvathoor; Veeranarayanan, Srivani; Yoshida, Yasuhiko; Maekawa, Toru; Sakthi Kumar, D.

    2012-01-01

    Nanocrystals (NCs) with anisotropic dimensions display polarized emission compared to nano dots. Triangular prisms are good candidates for polarized optical properties and monodisperse triangular NCs are ideal for developing building blocks for novel three-dimensional superlattices due to its anisotropic dimension. Among triangular nanocrystals, CdS nanocrystals are less discussed for the past one decade of research due to the difficulty in its processing method. Though well studied very few methods for developing CdS triangular nanocrystals have been reported, and most are having drawbacks either due to the time consuming process or the products are combination of triangular as well as many other shaped NC or with trap emissions due to defects which are comparable to band emissions limits its applications in full scale. Here, we are presenting a novel method to develop 7 nm CdS triangular NCs that can solve the above mentioned problems, which would augment the usage of CdS triangular crystals for many applications, based on its anisotropic properties.

  4. ORF Alignment: cds [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available cds gnl|CMER >1wfiA 3 125 209 328 1e-34 ... ref|NP_705268.1| nuclear movement protein..., putative [Plasmodium falciparum 3D7] ... emb|CAD52505.1| nuclear movement protein, putative ...

  5. GenBank blastx search result: AK104368 [KOME

    Lifescience Database Archive (English)

    Full Text Available , ureE, ureF genes for urease beta subunit UreB, urease alpha subunit UreC, urease gamma subunit UreA, urease... accessory protein UreG, urease accessory protein UreD, urease accessory protein UreE, urease accessory protein UreF, complete cds.|BCT BCT 1e-46 +1 ... ...AK104368 001-035-E04 AB119092.1 Haloarcula marismortui ureB, ureC, ureA, ureG, ureD

  6. GenBank blastx search result: AK104368 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104368 001-035-E04 AF056321.1 Actinomyces naeslundii urease gamma subunit UreA (ureA), urease... beta subunit UreB (ureB), urease alpha subunit UreC (ureC), urease accessory protein UreE (ureE), urease... accessory protein UreF (ureF), urease accessory protein UreG (ureG), and urease accessory protein UreD (ureD) genes, complete cds.|BCT BCT 3e-48 +1 ...

  7. ORF Alignment: cds [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available cds gnl|CMER >1sg6B 30 343 72 371 7e-54 ... dbj|BAD07382.1| putative 2-epi-5-epi-valiolone synthase [Actinopla...nes sp. A40644] ... Length = 300 ... Query: 89 ... SRRFCVVDDSVWAIYGEKLKAYFDERNIASK

  8. Optical Sensor Based on a Single CdS Nanobelt

    Directory of Open Access Journals (Sweden)

    Lei Li

    2014-04-01

    Full Text Available In this paper, an optical sensor based on a cadmium sulfide (CdS nanobelt has been developed. The CdS nanobelt was synthesized by the vapor phase transportation (VPT method. X-Ray Diffraction (XRD and Transmission Electron Microscopy (TEM results revealed that the nanobelt had a hexagonal wurtzite structure of CdS and presented good crystal quality. A single nanobelt Schottky contact optical sensor was fabricated by the electron beam lithography (EBL technique, and the device current-voltage results showed back-to-back Schottky diode characteristics. The photosensitivity, dark current and the decay time of the sensor were 4 × 104, 31 ms and 0.2 pA, respectively. The high photosensitivity and the short decay time were because of the exponential dependence of photocurrent on the number of the surface charges and the configuration of the back to back Schottky junctions.

  9. Modification of optical and electrical properties of chemical bath deposited CdS using plasma treatments

    International Nuclear Information System (INIS)

    Gonzalez, G.; Krishnan, B.; Avellaneda, D.; Castillo, G. Alan; Das Roy, T.K.; Shaji, S.

    2011-01-01

    Cadmium sulphide (CdS) is a well known n-type semiconductor that is widely used in solar cells. Here we report preparation and characterization of chemical bath deposited CdS thin films and modification of their optical and electrical properties using plasma treatments. CdS thin films were prepared from a chemical bath containing Cadmium chloride, Triethanolamine and Thiourea under various deposition conditions. Good quality thin films were obtained during deposition times of 5, 10 and 15 min. CdS thin films prepared for 10 min. were treated using a glow discharge plasma having nitrogen and argon carrier gases. The changes in morphology, optical and electrical properties of these plasma treated CdS thin films were analyzed in detail. The results obtained show that plasma treatment is an effective technique in modification of the optical and electrical properties of chemical bath deposited CdS thin films.

  10. Modification of optical and electrical properties of chemical bath deposited CdS using plasma treatments

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, G. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon, C.P 66450 (Mexico); Krishnan, B. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon, C.P 66450 (Mexico); CIIDIT, Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); Avellaneda, D.; Castillo, G. Alan; Das Roy, T.K. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon, C.P 66450 (Mexico); Shaji, S., E-mail: sshajis@yahoo.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon, C.P 66450 (Mexico); CIIDIT, Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico)

    2011-08-31

    Cadmium sulphide (CdS) is a well known n-type semiconductor that is widely used in solar cells. Here we report preparation and characterization of chemical bath deposited CdS thin films and modification of their optical and electrical properties using plasma treatments. CdS thin films were prepared from a chemical bath containing Cadmium chloride, Triethanolamine and Thiourea under various deposition conditions. Good quality thin films were obtained during deposition times of 5, 10 and 15 min. CdS thin films prepared for 10 min. were treated using a glow discharge plasma having nitrogen and argon carrier gases. The changes in morphology, optical and electrical properties of these plasma treated CdS thin films were analyzed in detail. The results obtained show that plasma treatment is an effective technique in modification of the optical and electrical properties of chemical bath deposited CdS thin films.

  11. Optical characterization of CdS nanoparticles embedded into the comb-type amphiphilic graft copolymer

    Science.gov (United States)

    Kalaycı, Özlem A.; Duygulu, Özgür; Hazer, Baki

    2013-01-01

    This study refers to the synthesis and characterization of a novel organic/inorganic hybrid nanocomposite material containing cadmium sulfide (CdS) nanoparticles. For this purpose, a series of polypropylene (PP)-g-polyethylene glycol (PEG), PP-g-PEG comb-type amphiphilic graft copolymers were synthesized. PEGs with Mn = 400, 2000, 3350, and 8000 Da were used and the graft copolymers obtained were coded as PPEG400, PPEG2000, PPEG3350, and PPEG8000. CdS nanoparticles were formed in tetrahydrofuran solution of PP-g-PEG amphiphilic comb-type copolymer by the reaction between aqueous solutions of Na2S and Cd(CH3COO)2 simultaneously. Micelle formation of PPEG2000 comb-type amphiphilic graft copolymer in both solvent/non-solvent (petroleum ether-THF) by transmission electron microscopy (TEM). The optical characteristics, size morphology, phase analysis, and dispersion of CdS nanoparticles embedded in PPEG400, PPEG2000, PPEG3350, and PPEG8000 comb-type amphiphilic graft copolymer micelles were determined by high resolution TEM (HRTEM), energy dispersive spectroscopy, UV-vis spectroscopy, and fluorescence emission spectroscopy techniques. The aggregate size of PPEG2000-CdS is between 10 and 50 nm; however, in the case of PPEG400-CdS, PPEG3350-CdS, and PPEG8000-CdS samples, it is up to approximately 100 nm. The size of CdS quantum dots in the aggregates for PPEG2000 and PPEG8000 samples was observed as 5 nm by HRTEM analysis, and this result was also supported by UV-vis absorbance spectra and fluorescence emission spectra.

  12. Optical characterization of CdS nanoparticles embedded into the comb-type amphiphilic graft copolymer

    Energy Technology Data Exchange (ETDEWEB)

    Kalayc Latin-Small-Letter-Dotless-I , Oezlem A. [Bulent Ecevit University, Department of Physics (Turkey); Duygulu, Oezguer [TUBITAK Marmara Research Center, Materials Institute (Turkey); Hazer, Baki, E-mail: bkhazer@karaelmas.edu.tr [Bulent Ecevit University, Department of Chemistry (Turkey)

    2013-01-15

    This study refers to the synthesis and characterization of a novel organic/inorganic hybrid nanocomposite material containing cadmium sulfide (CdS) nanoparticles. For this purpose, a series of polypropylene (PP)-g-polyethylene glycol (PEG), PP-g-PEG comb-type amphiphilic graft copolymers were synthesized. PEGs with Mn = 400, 2000, 3350, and 8000 Da were used and the graft copolymers obtained were coded as PPEG400, PPEG2000, PPEG3350, and PPEG8000. CdS nanoparticles were formed in tetrahydrofuran solution of PP-g-PEG amphiphilic comb-type copolymer by the reaction between aqueous solutions of Na{sub 2}S and Cd(CH{sub 3}COO){sub 2} simultaneously. Micelle formation of PPEG2000 comb-type amphiphilic graft copolymer in both solvent/non-solvent (petroleum ether-THF) by transmission electron microscopy (TEM). The optical characteristics, size morphology, phase analysis, and dispersion of CdS nanoparticles embedded in PPEG400, PPEG2000, PPEG3350, and PPEG8000 comb-type amphiphilic graft copolymer micelles were determined by high resolution TEM (HRTEM), energy dispersive spectroscopy, UV-vis spectroscopy, and fluorescence emission spectroscopy techniques. The aggregate size of PPEG2000-CdS is between 10 and 50 nm; however, in the case of PPEG400-CdS, PPEG3350-CdS, and PPEG8000-CdS samples, it is up to approximately 100 nm. The size of CdS quantum dots in the aggregates for PPEG2000 and PPEG8000 samples was observed as 5 nm by HRTEM analysis, and this result was also supported by UV-vis absorbance spectra and fluorescence emission spectra.

  13. Optical characterization of CdS nanoparticles embedded into the comb-type amphiphilic graft copolymer

    International Nuclear Information System (INIS)

    Kalaycı, Özlem A.; Duygulu, Özgür; Hazer, Baki

    2013-01-01

    This study refers to the synthesis and characterization of a novel organic/inorganic hybrid nanocomposite material containing cadmium sulfide (CdS) nanoparticles. For this purpose, a series of polypropylene (PP)-g-polyethylene glycol (PEG), PP-g-PEG comb-type amphiphilic graft copolymers were synthesized. PEGs with Mn = 400, 2000, 3350, and 8000 Da were used and the graft copolymers obtained were coded as PPEG400, PPEG2000, PPEG3350, and PPEG8000. CdS nanoparticles were formed in tetrahydrofuran solution of PP-g-PEG amphiphilic comb-type copolymer by the reaction between aqueous solutions of Na 2 S and Cd(CH 3 COO) 2 simultaneously. Micelle formation of PPEG2000 comb-type amphiphilic graft copolymer in both solvent/non-solvent (petroleum ether–THF) by transmission electron microscopy (TEM). The optical characteristics, size morphology, phase analysis, and dispersion of CdS nanoparticles embedded in PPEG400, PPEG2000, PPEG3350, and PPEG8000 comb-type amphiphilic graft copolymer micelles were determined by high resolution TEM (HRTEM), energy dispersive spectroscopy, UV–vis spectroscopy, and fluorescence emission spectroscopy techniques. The aggregate size of PPEG2000-CdS is between 10 and 50 nm; however, in the case of PPEG400-CdS, PPEG3350-CdS, and PPEG8000-CdS samples, it is up to approximately 100 nm. The size of CdS quantum dots in the aggregates for PPEG2000 and PPEG8000 samples was observed as 5 nm by HRTEM analysis, and this result was also supported by UV–vis absorbance spectra and fluorescence emission spectra.

  14. Study of optical phonon modes of CdS nanoparticles using Raman

    Indian Academy of Sciences (India)

    In this paper we report the study of optical phonon modes of nanoparticles of CdS using Raman spectroscopy. Nanoparticle sample for the present study was synthesized through chemical precipitation technique. The CdS nanoparticles were then subjected to heat treatment at low temperature (150°C) for extended time ...

  15. CDS User survey

    CERN Multimedia

    CERN Document Service

    2011-01-01

      The CERN Document Server is launching a user survey in order to collect information relative to its search engine, submission interfaces, collaborative features and content organisation. With the view of re-shaping its collections and interfaces and to better integrate with the new INSPIRE platform that serves all HEP literature, CERN Document Server team invites you to take part in the survey. Your input is essential to provide us with useful information before setting up the new service and improve your interactions with CDS. Thanks for participating !  

  16. Mixed-solvothermal synthesis of CdS micro/nanostructures and their optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Zhong Shengliang, E-mail: zslxhx@yahoo.com.cn [College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022 (China); Zhang Linfei; Huang Zhenzhong; Wang Shangping [College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022 (China)

    2011-01-15

    Several novel cadmium sulfide (CdS) micro/nanostructures, including cauliflower-like microspheres, football-like microspheres, tower-like microrods, and dendrites were controllably prepared via an oxalic acid-assisted solvothermal route using ethylene glycol (EG) and H{sub 2}O as pure and mixed solvents with different S sources. The as-prepared products were characterized by X-ray powder diffraction (XRD), scanning electronic microscope (SEM) and UV-vis spectrophotometer (UV). It was found that CdS micro/nanostructures can be selectively obtained by varying the composition of solvent, concentration of oxalic acid, and sulfur sources. UV-vis absorption spectra reveal that their absorption properties are shape-dependent. The possible formation process of the CdS micro/nanostructures was briefly discussed. This route provides a facile way to tune the morphologies of CdS over a wide range.

  17. ORF Alignment: cds [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available cds gnl|CMER >1g8pA 7 306 385 684 6e-05 ... emb|CAD25272.1| DNA REPLICATION LICENSING... FACTOR MCM2 [Encephalitozoon cuniculi ... GB-M1] ref|NP_584768.1| DNA REPLICATION LICENSING FACTOR ...

  18. Microwave Synthesized Monodisperse CdS Spheres of Different Size and Color for Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Carlos A. Rodríguez-Castañeda

    2015-01-01

    Full Text Available Monodisperse CdS spheres of size of 40 to 140 nm were obtained by microwave heating from basic solutions. It is observed that larger CdS spheres were formed at lower solution pH (8.4–8.8 and smaller ones at higher solution pH (10.8–11.3. The color of CdS products changed with solution pH and reaction temperature; those synthesized at lower pH and temperature were of green-yellow color, whereas those formed at higher pH and temperature were of orange-yellow color. A good photovoltage was observed in CdS:poly(3-hexylthiophene solar cells with spherical CdS particles. This is due to the good dispersion of CdS nanoparticles in P3HT solution that led to a large interface area between the organic and inorganic semiconductors. Higher photocurrent density was obtained in green-yellow CdS particles of lower defect density. The efficient microwave chemistry accelerated the hydrolysis of thiourea in pH lower than 9 and produced monodisperse spherical CdS nanoparticles suitable for solar cell applications.

  19. Optical properties of CdS thin films by (SILAR) method

    International Nuclear Information System (INIS)

    Ates, A.; Gurbulak, B.; Yildirim, M.

    2004-01-01

    Full text: CdS thin film was grown by Successive ionic layer adsorption and reaction (SILAR) technique on quartz substrate. The film homogeneous of film is good and the film colour obtained as orange. Optical properties of CdS thin film has been investigated as a function of temperature in the temperature range 10-320 K with 10 K steps. The band gap energy decreased with increasing temperature

  20. Investigation of the photoluminescence properties of thermochemically synthesized CdS nanocrystals

    Directory of Open Access Journals (Sweden)

    M. Molaei

    2011-03-01

    Full Text Available In this work we have synthesized CdS nanocrystals with thermochemical method. CdSO4 and Na2S2O3 were used as the precursors and thioglycolic acid (TGA was used as capping agent molecule. The structure and optical property of the nanocrystals were characterized by means of XRD, TEM, UV-visible optical spectroscopy and photoluminescence (PL. X-ray diffraction (XRD and TEM analyses demonstrated hexagonal phase CdS nanocrystals with an average size around 2 nm. Synthesized nanocrystals exhibited band gap of about 3.2 eV and showed a broad band emission from 400-750 nm centered at 504 nm with a (0.27, 0.39 CIE coordinate. This emission can be attributed to recombination of an electron in conduction band with a hole trapped in Cd vacancies near to the valance band of CdS. The best attained photoluminescence quantum yield of the nanocrystals was about 12%, this amount is about 20 times higher than that for thioglycerol (TG capped CdS nanocrystals.

  1. Amorphous MoS{sub x} on CdS nanorods for highly efficient photocatalytic hydrogen evolution

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaofang; Tang, Chaowan; Zheng, Qun; Shao, Yu; Li, Danzhen, E-mail: dzli@fzu.edu.cn

    2017-02-15

    Loading cocatalyst on semiconductors was crucially necessary for improving the photocatalytic hydrogen evolution. Amorphous MoS{sub x} as a novel and noble metal-free cocatalyst was loaded on CdS nanorods by a simple photodeposition method. Efficient hydrogen evolution with amount of 15 mmol h{sup −1} g{sup −1} was observed over the MoS{sub x} modified CdS nanorods, which was about 6 times higher than that by using Pt as cocatalyst. Meanwhile, with MoS{sub x} cocatalyst, the efficiency of CdS nanorods was superior to that of CdS nanoparticles and bulk CdS. No deactivation could be observed in the efficiency of MoS{sub x} modified CdS nanorods under irradiation for successive 10 h. Further experimental results indicated that the efficient electrons transfer, low overpotential of hydrogen evolution and active S atoms over the MoS{sub x} modified CdS nanorods were responsible for the higher efficiency. Our results provided guidance for synthesizing noble metal-free materials as cocatalyst for photocatalytic hydrogen evolution. - Graphical abstract: Photodeposition of amorphous MoS{sub x} on CdS nanorods for highly efficient photocatalytic hydrogen evolution. - Highlights: • Amorphous MoSx cocatalyst was loaded on CdS NRs by a simple photodeposition. • MoS{sub x}/CdS NRs exhibited 6 times higher hydrogen evolution efficiency than Pt/CdS NRs. • The hydrogen evolution of MoS{sub x}/CdS NRs linearly increased with prolonging time. • Lower overpotential and efficient electron transfer were observed over MoS{sub x}/CdS NRs.

  2. Microstructural and optical properties of CdS nanoparticles synthesized by sol gel method

    Science.gov (United States)

    Mahdi, Hadeel Salih; Parveen, Azra; Agrawal, Shraddha; Azam, Ameer

    2018-05-01

    Semiconductor nanoparticles of CdS are of great interest for both fundamental research and industrial development due to their unique size-dependent optical and electronic properties and their exciting utilization in the fields of light-emitting diode, electro-chemical cells, laser, hydrogen producing catalyst, biological label. We present a scheme to measure the optical properties of CdS nanoparticles The peaks were indexed by powder-x software. The XRD pattern analysis showed that CdS composition was found to have hexagonal structure with well crystalline nature. the surface morphology and the composition of the samples were investigated by SEM (JEOL, japan). The image shows the presence of large spherical aggregates of smaller individual nanoparticles of various sizes for pure cds. to check the chemical composition of the material, energy dispersive X-ray (EDX) spectroscopic analysis was also performed which further confirmed the presence of cd and s ions in the matrix. The optical absorption spectra of CdS sample was recorded by uv-vis spectrophotometer in the range of 200 to 800 nm.

  3. Photosensitization of TiO2 P25 with CdS Nanoparticles for Photocatalytic Applications

    Directory of Open Access Journals (Sweden)

    Trenczek-Zając A.

    2017-06-01

    Full Text Available A TiO2/CdS coupled system was prepared by mixing the TiO2 P25 with CdS synthesized by means of the precipitation method. It was found that the specific surface area (SSA of both components is extremely different and equals 49.5 for TiO2 and 145.4 m2·g−1 for CdS. The comparison of particle size distribution and images obtained by means of transmission electron microscopy (TEM showed agglomeration of nanocomposites. X-ray diffraction (XRD patterns suggest that CdS crystallizes in a mixture of cubic and hexagonal phases. Optical reflectance spectra revealed a gradual shift of the fundamental absorption edge towards longer wavelengths with increasing CdS molar fraction, which indicates an extension of the absorption spectrum of TiO2. The photocatalytic activity in UV and UV-vis was tested with the use of methyl orange (MO. The Langmuir–Hinshelwood model described well the photodegradation process of MO. The results showed that the photocatalytic behaviour of the TiO2/CdS mixture is significantly better than that of pure nanopowders.

  4. Morphology, structure and optical properties of hydrothermally synthesized CeO2/CdS nanocomposites

    Science.gov (United States)

    Mohanty, Biswajyoti; Nayak, J.

    2018-04-01

    CeO2/CdS nanocomposites were synthesized using a two-step hydrothermal technique. The effects of precursor concentration on the optical and structural properties of the CeO2/CdS nanoparticles were systematically studied. The morphology, composition and the structure of the CeO2/CdS nanocomposite powder were studied by scanning electron microscopy (SEM), energy dispersive X-ray spectrum analysis (EDXA) and X-ray diffraction (XRD), respectively. The optical properties of CeO2/CdS nanocomposites were studied by UV-vis absorption and photoluminescence (PL) spectroscopy. The optical band gaps of the CeO2/CdS nanopowders ranged from 2.34 eV to 2.39 eV as estimated from the UV-vis absorption. In the room temperature photoluminescence spectrum of CeO2/CdS nanopowder, a strong blue emission band was observed at 400 nm. Since the powder shows strong visible luminescence, it may be used as a blue phosphor in future. The original article published with this DOI was submitted in error. The correct article was inadvertently left out of the original submission. This has been rectified and the correct article was published online on 16 April 2018.

  5. Physical properties and characterization of Ag doped CdS thin films

    International Nuclear Information System (INIS)

    Shah, N.A.; Nazir, A.; Mahmood, W.; Syed, W.A.A.; Butt, S.; Ali, Z.; Maqsood, A.

    2012-01-01

    Highlights: ► CdS thin films were grown. ► By ion exchange, Ag was doped. ► Physical properties were investigated. - Abstract: Thin films of cadmium sulfide with very well defined preferential orientation and relatively high absorption coefficient were fabricated by thermal evaporation technique. The research is focused to the fabrication and characterization of the compositional data of CdS thin films obtained by using X-ray diffraction, scanning electron microscope along with energy dispersive X-ray spectroscopy. The optical properties were studied by using a UV-VIS-NIR spectrophotometer. The effects of silver-doping by ion exchange process on the properties of as-deposited CdS thin films have been investigated.

  6. Synthesis of CdS hollow/solid nanospheres and their chain-structures by membrane technique

    International Nuclear Information System (INIS)

    Duan Shumin; Wu Qingsheng; Jia Runping; Liu Xinbo

    2008-01-01

    CdS hollow/solid nanospheres and their chain-structures were successfully synthesized through supporting liquid membrane (SLM) system with bio-membrane. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV-Vis spectroscopy, and photoluminescence (PL) spectroscopy have been used for the characterization of the products. The average diameters of CdS solid/hollow spheres are about 10, 40 nm, respectively. The wall of the hollow spheres is about 5 nm. CdS products are all cubic face-centered structure with the cell constant a = 5.830 A. We also explore the morphology, structure and possible synthesis mechanism. A possible template mechanism has been proposed for the production of the hollow CdS nanocrystals, that is, CdS nanoparticles grow along the non-soakage interface between CHCl3 and reactant solution. During this process, the organic functional groups were crucial to the control of crystal morphologies

  7. UNDERFLIGHT CALIBRATION OF SOHO/CDS AND HINODE/EIS WITH EUNIS-07

    Energy Technology Data Exchange (ETDEWEB)

    Wang Tongjiang; Brosius, Jeffrey W. [Institute for Astrophysics and Computational Sciences (IACS) in the Department of Physics, Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064 (United States); Thomas, Roger J.; Rabin, Douglas M.; Davila, Joseph M. [NASA Goddard Space Flight Center, Code 671, Greenbelt, MD 20771 (United States); Young, Peter R. [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Del Zanna, Giulio, E-mail: tongjiang.wang@nasa.gov [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)

    2011-12-01

    Flights of Goddard Space Flight Center's Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket in 2006 and 2007 provided updated radiometric calibrations for Solar and Heliospheric Observatory/Coronal Diagnostic Spectrometer (SOHO/CDS) and Hinode/Extreme Ultraviolet Imaging Spectrometer (Hinode/EIS). EUNIS carried two independent imaging spectrographs covering wavebands of 300-370 A in first order and 170-205 A in second order. After each flight, end-to-end radiometric calibrations of the rocket payload were carried out in the same facility used for pre-launch calibrations of CDS and EIS. During the 2007 flight, EUNIS, SOHO/CDS, and Hinode/EIS observed the same solar locations, allowing the EUNIS calibrations to be directly applied to both CDS and EIS. The measured CDS NIS 1 line intensities calibrated with the standard (version 4) responsivities with the standard long-term corrections are found to be too low by a factor of 1.5 due to the decrease in responsivity. The EIS calibration update is performed in two ways. One uses the direct calibration transfer of the calibrated EUNIS-07 short wavelength (SW) channel. The other uses the insensitive line pairs, in which one member was observed by the EUNIS-07 long wavelength (LW) channel and the other by EIS in either the LW or SW waveband. Measurements from both methods are in good agreement, and confirm (within the measurement uncertainties) the EIS responsivity measured directly before the instrument's launch. The measurements also suggest that the EIS responsivity decreased by a factor of about 1.2 after the first year of operation (although the size of the measurement uncertainties is comparable to this decrease). The shape of the EIS SW response curve obtained by EUNIS-07 is consistent with the one measured in laboratory prior to launch. The absolute value of the quiet-Sun He II 304 A intensity measured by EUNIS-07 is consistent with the radiance measured by CDS NIS in quiet regions

  8. Luminescence studies of CdS spherical particles via hydrothermal synthesis

    Science.gov (United States)

    Xu, Guo Qin; Liu, Bing; Xu, Shi Jie; Chew, Chwee Har; Chua, Soo Jin; Gana, Leong Ming

    2000-06-01

    The spherical particles of CdS consisting of nanoparticles (∼100 nm) were synthesized by a hydrothermal process. The particle formation and growth depend on the rate of sulfide-ion generation and diffusion-controlled aggregation of nanoparticles. As demonstrated in the profiles of powder X-ray diffraction, the crystalline phases are governed by the reaction temperature. Photoluminescence studies on CdS particles show two emission bands at the room temperature. The red emission at 680 nm is due to sulfur vacancies, and a new infrared red (IR) emission at 760 nm is attributed to self-activated centers. A red shift of IR band with the decrease of temperature was explained with a configurational coordinate model. The different saturation limits for the red and IR bands are discussed in terms of the formation of donor-acceptor pairs and exciton in CdS particles.

  9. Diffusion mediated agglomeration of CdS nanoparticles via Langmuir–Blodgett technique

    International Nuclear Information System (INIS)

    Das, Nayan Mani; Roy, Dhrubojyoti; Gupta, P.S.

    2013-01-01

    Graphical abstract: - Highlights: • Diffusion mediated agglomeration of CdS nanoparticles are discussed. • Formation of CdS nanoparticles are confirmed by the change of chain length in XRD. • AFM shows the agglomeration of particles with a film swelling of about 5 Å. • UV–vis absorbance suggests that the grown particles show quantum confinement. • Hexagonal form of particle was confirmed by UV–vis reflectivity. - Abstract: We have reported a diffusion mediated agglomeration of cadmium sulphide (CdS) nanoparticles within cadmium arachidate (CdA 2 ) film matrix. The structural morphology and formation of CdS nanoparticles are characterized by X-ray diffraction (XRD), X-ray reflectivity (XRR), atomic force microscopy (AFM) and ultraviolet-visible spectroscopy techniques. X-ray diffraction (XRD) results show a change in bilayer difference from 53.04 Å to 43 Å after the sulphidation. An epitaxial growth of the films by ∼5 Å after sulphidation is confirmed from atomic force microscopy studies. The particle size calculated form UV–vis absorption edges are found to be varying from 2.6 nm to 3.3 nm for the different layers. A lateral dimension of 72–80 nm from AFM measurements and a size of 2.6–3.3 nm have confirmed one side flat pseudo two-dimensional disk-like nanoparticles. UV–vis reflectivity peak at E 1 (A) confirms the formation of hexagonal CdS nanoparticles along the c-axis

  10. Soft-template synthesis of single-crystalline CdS dendrites.

    Science.gov (United States)

    Niu, Haixia; Yang, Qing; Tang, Kaibin; Xie, Yi; Zhu, Yongchun

    2006-01-01

    The single-crystalline CdS dendrites have been fabricated from the reaction of CdCl2 and thiourea at 180 degrees C, in which glycine was employed as a soft template. The obtained products were explored by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and selected area electronic diffraction. The optical properties of CdS dendrites have been investigated by ultraviolet and visible light (UV-vis) and photoluminescence techniques. The investigations indicated that the dendrites were grown due to the anisotropic properties enhanced by the use of Glycine in the route.

  11. Structural, morphological and optical properties of Na and K dual doped CdS thin film

    International Nuclear Information System (INIS)

    Mageswari, S.; Dhivya, L.; Palanivel, Balan; Murugan, Ramaswamy

    2012-01-01

    Highlights: ► Effect of incorporation of Na, K and Na,K dual dopants into CdS thin film was investigated. ► Thin films were prepared by simple chemical bath deposition technique. ► The XRD analysis revealed cubic phase for all the investigated films. ► AFM analysis revealed uniform surface with crack free and densely packed morphology for CdS:Na,K film. ► The band gap value increases for CdS:Na, CdS:K and CdS:Na,K thin films compared to CdS film. - Abstract: CdS, sodium doped CdS (CdS:Na), potassium doped CdS (CdS:K) and sodium and potassium dual doped CdS (CdS:Na,K) thin films were deposited on glass substrate by chemical bath deposition (CBD) technique. Structural, morphological and optical properties of the as-grown films were characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), atomic force microscopy (AFM) and ultraviolet visible (UV–VIS) spectroscopy. The XRD analysis revealed cubic phase for ‘as-deposited’ CdS, CdS:Na, CdS:K and CdS:Na,K dual doped thin films. AFM analysis revealed uniform film surface with crack free and densely packed morphology for CdS:Na,K film. The absorption edge in the optical absorption spectra shifts towards the shorter wavelength for CdS:Na, CdS:K and CdS:Na,K thin films compared to CdS film. The optical band gap of CdS, CdS:Na, CdS:K and CdS:Na,K thin films was found to be 2.31, 2.35, 2.38 and 2.34 eV, respectively.

  12. Synthesis of water soluble CdS nanoparticles and study of their DNA damage activity

    Directory of Open Access Journals (Sweden)

    Kumar Suranjit Prasad

    2017-05-01

    Full Text Available This study reports a novel method for preparation of water soluble CdS nanoparticles using leaf extract of a plant, Asparagus racemosus. The extract of the leaf tissue which worked as a stabilizing and capping agent, assisted the formation of nanoparticles. Nanoparticles were characterized using a UV–vis spectrophotometer, Photoluminescence, TEM, EDAX, XRD and FT-IR. Transmission electron microscopy followed by selected area electron diffraction pattern analysis indicated the formation of spherical, polydispersed, crystalline, CdS of diameter ranging from 2 to 8 nm. X-ray diffraction studies showed the formation of 111, 220 and 311 planes of face-centered cubic (fcc CdS. EDAX analysis confirmed the presence of Cd and S in nanosphere. The cytotoxicity test using MTT assay as well as DNA damage analysis using comet assay revealed that synthesized nano CdS quantum dots (QDs caused less DNA damage and cell death of lymphocytes than pure CdS nanoparticles.

  13. Preparation and Characterization of TiO2/CdS Layers as Potential Photoelectrocatalytic Materials

    Directory of Open Access Journals (Sweden)

    Teofil-Danut Silipas

    2011-01-01

    Full Text Available The TiO2/CdS semiconductor composites were prepared on
    indium tin oxide (ITO substrates in di®erent mass proportions via wet-chemical techniques using bi-distilled water, acetyl-acetone, poly-propylene-glycol and Triton X-100 as additives. The composite layers were annealed in normal conditions at the temperature of 450±C, 120 min. with a rate of temperature increasing of 5±C/min. The structural and optical properties of all the TiO2/CdS ayers were characterized by X-ray di®raction, UV-VIS spectroscopy, spectrofluorimetry and FT/IR microscopy. The microstructural properties of the deposited TiO2/CdS layers can be modi¯ed by varying the mass proportions of TiO2:CdS. The good crystallinity level and the high optical adsorption of
    the TiO2/CdS layers make them attractive for photoelectrochemical cell applications.

  14. Structural and optical characterization of CdS nanorods synthesized by a PVA-assisted solvothermal method

    International Nuclear Information System (INIS)

    Wang Hongmei; Fang Pengfei; Chen Zhe; Wang Shaojie

    2008-01-01

    Cadmium sulphide (CdS) 1D nanocrystals were prepared using a simple poly(vinyl-alcohol) (PVA)-assisted solvothermal method which employed ethylenediamine (en) as solvent. The obtained nanorods were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-vis) absorption, and photoluminescence (PL) spectra. XRD results show that the nanorods are hexagonal phase. The TEM results indicate that the synthesized CdS nanorods with PVA-assisted showed larger aspect ratio and uniform faces compared with the sample prepared in the absence of PVA. The results of the photoluminescence and UV-vis spectroscopy measurements reveal that the as-prepared CdS nanorods show a quantum confinement effect. It is also found that the dosage of PVA is a vital factor in the morphology and optical properties of CdS nanorods. Moreover, when the best dosage of 3 g PVA/70 ml en was used, CdS nanorods with regular morphology and longer length were obtained. The probable mechanism for PVA-assisted solvothermal synthesis of CdS nanorods was also discussed

  15. L1000CDS2: LINCS L1000 characteristic direction signatures search engine.

    Science.gov (United States)

    Duan, Qiaonan; Reid, St Patrick; Clark, Neil R; Wang, Zichen; Fernandez, Nicolas F; Rouillard, Andrew D; Readhead, Ben; Tritsch, Sarah R; Hodos, Rachel; Hafner, Marc; Niepel, Mario; Sorger, Peter K; Dudley, Joel T; Bavari, Sina; Panchal, Rekha G; Ma'ayan, Avi

    2016-01-01

    The library of integrated network-based cellular signatures (LINCS) L1000 data set currently comprises of over a million gene expression profiles of chemically perturbed human cell lines. Through unique several intrinsic and extrinsic benchmarking schemes, we demonstrate that processing the L1000 data with the characteristic direction (CD) method significantly improves signal to noise compared with the MODZ method currently used to compute L1000 signatures. The CD processed L1000 signatures are served through a state-of-the-art web-based search engine application called L1000CDS 2 . The L1000CDS 2 search engine provides prioritization of thousands of small-molecule signatures, and their pairwise combinations, predicted to either mimic or reverse an input gene expression signature using two methods. The L1000CDS 2 search engine also predicts drug targets for all the small molecules profiled by the L1000 assay that we processed. Targets are predicted by computing the cosine similarity between the L1000 small-molecule signatures and a large collection of signatures extracted from the gene expression omnibus (GEO) for single-gene perturbations in mammalian cells. We applied L1000CDS 2 to prioritize small molecules that are predicted to reverse expression in 670 disease signatures also extracted from GEO, and prioritized small molecules that can mimic expression of 22 endogenous ligand signatures profiled by the L1000 assay. As a case study, to further demonstrate the utility of L1000CDS 2 , we collected expression signatures from human cells infected with Ebola virus at 30, 60 and 120 min. Querying these signatures with L1000CDS 2 we identified kenpaullone, a GSK3B/CDK2 inhibitor that we show, in subsequent experiments, has a dose-dependent efficacy in inhibiting Ebola infection in vitro without causing cellular toxicity in human cell lines. In summary, the L1000CDS 2 tool can be applied in many biological and biomedical settings, while improving the extraction of

  16. Enhanced photoelectrochemical properties of TiO2 nanorod arrays decorated with CdS nanoparticles

    International Nuclear Information System (INIS)

    Xie, Zheng; Wang, Weipeng; Liu, Can; Li, Zhengcao; Liu, Xiangxuan; Zhang, Zhengjun

    2014-01-01

    TiO 2 nanorod arrays (TiO 2 NRAs) sensitized with CdS nanoparticles were fabricated via successive ion layer adsorption and reaction (SILAR), and TiO 2 NRAs were obtained by oxidizing Ti NRAs obtained through oblique angle deposition. The TiO 2 NRAs decorated with CdS nanoparticles exhibited excellent photoelectrochemical and photocatalytic properties under visible light, and the one decorated with 20 SILAR cycles CdS nanoparticles shows the best performance. This can be attributed to the enhanced separation of electrons and holes by forming heterojunctions of CdS nanoparticles and TiO 2 NRAs. This provides a promising way to fabricate the material for solar energy conversion and wastewater degradation. (paper)

  17. Photovoltaic performance enhancement of CdS quantum dot-sensitized TiO2 photoanodes with plasmonic gold nanoparticles

    International Nuclear Information System (INIS)

    Liu, Aiping; Ren, Qinghua; Zhao, Ming; Xu, Tao; Yuan, Ming; Zhao, Tingyu; Tang, Weihua

    2014-01-01

    Highlights: • CdS QD-sensitized TiO 2 porous photoanode with plasmonic gold. • A prominent light absorption enhancement of hybrid was attained by gold plasmon. • The photovoltaic response of hybrid was tunable by CdS amount. • The Au/TiO 2 /CdS hybrid had a potential application in energy conversion devices. -- Abstract: The CdS quantum dot-sensitized TiO 2 films with plasmonic gold nanoparticles were designed as photoanodes by the electrodeposition of gold combined with the “successive ionic layer adsorption and reaction” (SILAR) method for CdS deposition on porous TiO 2 films. A prominent enhancement in light absorption of Au/TiO 2 /CdS hybrid was attained by efficient light scattering of gold plasmons as sub-wavelength antennas and concentrators. The photogenerated electron formed in the near-surface region of TiO 2 and CdS were facilitated to transfer to the plasmonic gold, resulting in the enhancement of photocurrent and incident photon-to-current conversion efficiency of hybrid photoanode upon photoirradiation. Furthermore, the photovoltaic response of hybrid was highly tunable with respect to the number of SILAR cycles applied to deposit CdS. The thicker absorber layer with less porous structure and larger CdS crystals might limit the electrolyte diffusion into the hybrid electrode and impose a barrier for electron tunneling and transferring. The highly versatile and tunable properties of Au/TiO 2 /CdS photoanodes demonstrated their potential application in energy conversion devices

  18. Anodic stripping voltammetry of synthesized CdS nanoparticles at boron-doped diamond electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Hayat, Mohammad; Ivandini, Tribidasari A., E-mail: ivandini.tri@sci.ui.ac.id; Saepudin, Endang [Department of Chemistry, FMIPA, Universitas Indonesia, Kampus UI Depok (Indonesia); Einaga, Yasuaki [Department of Chemistry, Keio University (Japan)

    2016-04-19

    Cadmium sulphide (CdS) nanoparticles were chemically synthesized using reverse micelles microreactor methods. By using different washing treatments, UV-Vis spectroscopy showed that the absorption peaks appeared at 465 nm, 462 nm, 460 nm, and 459 nm respectively for CdS nanoparticles without and with 1, 2, and 3 times washing treatments using pure water. In comparison with the absorbance peak of bulk CdS at 512 nm, the shifted absorption peaks, indicates that the different sizes of CdS can be prepared. Anodic stripping voltammetry of the CdS nanoparticles was then studied at a boron-doped diamond electrode using 0.1 M KClO{sub 4} and 0.1 M HClO{sub 4} as the electrolytes. A scan rate of 100 mV/s with a deposition potential of -1000 mV (vs. Ag/AgCl) for 60 s at a potential scan from -1600 mV to +800 mV (vs. Ag/AgCl) was applied as the optimum condition of the measurements. Highly-accurate linear calibration curves (R{sup 2} = 0.99) in 0.1 M HClO{sub 4} with the sensitivity of 0.075 mA/mM and the limit of detection of 81 µM in 0.1 M HClO{sub 4} can be achieved, which is promising for an application of CdS nanoparticles as a label for biosensors.

  19. Size-dependent photodegradation of CdS particles deposited onto TiO2 mesoporous films by SILAR method

    International Nuclear Information System (INIS)

    Ahmed, Rasin; Will, Geoffrey; Bell, John; Wang Hongxia

    2012-01-01

    The particle size, size distribution and photostability of CdS nanoparticles incorporated onto mesoporous TiO 2 films by a successive ionic layer adsorption and reaction (SILAR) method were investigated by Raman spectroscopy, UV–Visible spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). High-resolution TEM indicated that the synthesized CdS particles were hexagonal phase and the particle sizes were less than 5 nm for up to nine SILAR deposition cycles. Quantum size effect was found with the CdS-sensitized TiO 2 films prepared with up to nine SILAR cycles. The band gap of CdS nanoparticles decreased from 2.65 to 2.37 eV with the increase of the SILAR cycles from 1 to 11. The investigation of the stability of the CdS/TiO 2 films in air under illumination (440.6 μW/cm 2 ) showed that the photodegradation rate was up to 85 % per day for the sample prepared with three SILAR cycles. XPS analysis indicated that the photodegradation was due to the oxidation of CdS, leading to the transformation from sulphide to sulphate (CdSO 4 ). Furthermore, the degradation rate was strongly dependent upon the particle size of CdS. Smaller particles showed faster degradation rate. The size-dependent photo-induced oxidization was rationalized with the variation of size-dependent distribution of surface atoms of CdS particles. Molecular dynamics-based theoretical calculation has indicated that the surface sulphide anion of a large CdS particle such as CdS made with 11 cycles (CdS × 11, average particle size = 5.6 nm) accounts for 9.6 % of the material whereas this value is increased to 19.2 % for (CdS × 3)-based smaller particles (average particle size = 2.7 nm). The photostability of CdS nanoparticles was significantly enhanced when coated with ZnS particles deposited with four SILAR cycles. The growth mechanism of ZnS upon CdS nanoparticles was discussed.

  20. A 256×256 low-light-level CMOS imaging sensor with digital CDS

    Science.gov (United States)

    Zou, Mei; Chen, Nan; Zhong, Shengyou; Li, Zhengfen; Zhang, Jicun; Yao, Li-bin

    2016-10-01

    In order to achieve high sensitivity for low-light-level CMOS image sensors (CIS), a capacitive transimpedance amplifier (CTIA) pixel circuit with a small integration capacitor is used. As the pixel and the column area are highly constrained, it is difficult to achieve analog correlated double sampling (CDS) to remove the noise for low-light-level CIS. So a digital CDS is adopted, which realizes the subtraction algorithm between the reset signal and pixel signal off-chip. The pixel reset noise and part of the column fixed-pattern noise (FPN) can be greatly reduced. A 256×256 CIS with CTIA array and digital CDS is implemented in the 0.35μm CMOS technology. The chip size is 7.7mm×6.75mm, and the pixel size is 15μm×15μm with a fill factor of 20.6%. The measured pixel noise is 24LSB with digital CDS in RMS value at dark condition, which shows 7.8× reduction compared to the image sensor without digital CDS. Running at 7fps, this low-light-level CIS can capture recognizable images with the illumination down to 0.1lux.

  1. Observation of melting in 30 angstrom diameter CdS nanocrystals

    International Nuclear Information System (INIS)

    Goldstein, A.N.; Colvin, V.L.; Alivisatos, A.P.

    1991-01-01

    In this paper temperature dependent electron diffraction studies on 30 Angstrom diameter CdS nanocrystals are described. The linear thermal expansion coefficient of the nanocrystals is 2.75 * 10 -5 Angstrom/K, and the melting point is 575 K. These data are in contrast to bulk CdS which has a melting point of 1750 K and a linear expansion coefficient of 5.5 * 10 -6 Angstrom/K. The observed depression in the melting point of these semiconductor clusters is similar to effects observed in metals and molecular crystals, indicating that the phenomenon of reduced melting point in small systems is a general one regardless of the type of material. The observation of melting point depression in these clusters also has far reaching implications for the preparation of highly crystalline clusters of CdS, as well as for the use of these nanocrystals as precursors to thin films

  2. Preliminary Results from Coordinated UVCS-CDS-Ulysses Observations

    Science.gov (United States)

    Parenti, S.; Bromage, B. J.; Poletto, G.; Suess, S. T.; Raymond, J. C.; Noci, G.; Bromage, G. E.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    The June 2000 quadrature between the Sun, Earth, and Ulysses took place with Ulysses at a distance of 3.35 AU from the Sun and at heliocentric latitude 58.2 deg south, in the southeast quadrant. This provided an opportunity to observe the corona close to the Sun with Coronal Diagnostic Spectrometer (CDS) and Ultraviolet Coronograph Spectrometer (UVCS) and, subsequently, to sample the same plasma when it reached Ulysses. Here we focus on simultaneous observations of UVCS and CDS made on June 12, 13, 16 and 17. The UVCS data were acquired at heliocentric altitudes ranging from 1.6 to 2.2 solar radii, using different grating positions, in order to get a wide wavelength range. CDS data consisted of Normal Incidence Spectrometer (NIS) full wavelength rasters of 120" x 150" centered at altitudes up to 1.18 solar radii, together with Grazing Incidence Spectrometer (GIS) 4" x 4" rasters within the same field of view, out to 1.2 solar radii. The radial direction to Ulysses passed through a high latitude streamer, throughout the 4 days of observations, Analysis of the spectra taken by UVCS shows a variation of the element abundances in the streamer over our observing interval: however, because the observations were in slightly different parts of the streamer on different days, the variation could be ascribed either to a temporal or spatial effect. The oxygen abundance, however, seems to increase at the edge of the streamer, as indicated by previous analyses. This suggests the variation may be a function of position within the streamer, rather than a temporal effect. Oxygen abundances measured by SWICS on Ulysses are compared with the CDS and UVCS results to see whether changes measured in situ follow the same pattern.

  3. Electronic and optical properties of CdS films deposited by evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, L.; Wei, Z.L.; Zhang, F.M.; Wu, X.S., E-mail: xswu@nju.edu.cn

    2015-11-05

    CdS films grown by thermal evaporation on glass substrate under ultra-high vacuum are prepared with varying the growth temperature and atmosphere environment. The minimum resistivity of the films is as low as 2.0 Ω·cm, and the carrier density even reaches 1.6 × 10{sup 18} cm{sup −3}, which is much less than that prepared by the chemical bath deposition (CBD) method. The transmittance and band gap increase with the set the argon atmosphere and the growth temperature in the optimum value. Our results indicate the CdS films grown by evaporation at high vacuum may be more suitable for the application in optoelectronic devices, such as the solar cell materials. - Highlights: • CdS films are grown by the ultra-high vacuum evaporation. • CdS film here with the high carrier density reaches to 10{sup 18} cm{sup −3} is obtained. • The film has low resistivity, which is as low as 2 Ω∙ cm. • The optical band gap become wider from 2.42 eV to 2.54 eV.

  4. BI Reporting, Data Warehouse Systems, and Beyond. CDS Spotlight Report. Research Bulletin

    Science.gov (United States)

    Lang, Leah; Pirani, Judith A.

    2014-01-01

    This Spotlight focuses on data from the 2013 Core Data Service [CDS] to better understand how higher education institutions approach business intelligence (BI) reporting and data warehouse systems (see the Sidebar for definitions). Information provided for this Spotlight was derived from Module 8 of CDS, which contains several questions regarding…

  5. ORF Alignment: cds [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available cds gnl|CMER >1e79I 1 47 1 47 1e-07 ... pdb|1E79|I Chain I, Bovine F1-Atpase Inhibite...d By Dccd ... (Dicyclohexylcarbodiimide) pdb|1H8E|I Chain I, ... (Adp.Alf4)2(Adp.So4) Bovine F1-Atpase

  6. Effect of annealing time on optical and electrical properties of CdS thin films

    Science.gov (United States)

    Soliya, Vanshika; Tandel, Digisha; Patel, Chandani; Patel, Kinjal

    2018-05-01

    Cadmium sulphide (CdS) is semiconductor compound of II-VI group. Thin film of CdS widely used in the applications such as, a buffer layer in copper indium diselenide (CIS) hetrojunction based solar cells, transistors, photo detectors and light emitting diodes. Because of the ease of making like chemical bath deposition (CBD), screen printing and thermal evaporation. It is extensively used in the CIS based solar cells as a buffer layers. The buffer layers usually used for reducing the interface recombination of the photo generated carriers by means of improving the lattice mismatch between the layers. The optimum thickness and the optoelectronics properties of CdS thin films like, optical band gap, electrical resistivity, structure, and composition etc., are to be considering for its use as a buffer layer. In the present study the CdS thin film were grown by simple dip coating method. In this method we had prepared 0.1M Cadmium-thiourea precursor solution. Before the deposition process of CdS, glass substrate has been cleaned using Methanol, Acetone, Trichloroethylene and De-ionized (DI) water. After coating of precursor layer, it was heated at 200 °C for themolysis. Then after CdS films were annealed at 200 °C for different time and studied its influence on the optical transmission, band gap, XRD, raman and the electrical resistivity. As increasing the annealing time we had observed the average transmission of the films was reduce after the absorption edge. In addition to the blue shift of absorption edge was observed. The observed optimum band gap was around 2.50 eV. XRD and raman analysis confirms the cubuc phase of CdS. Hot probe method confirms the n-type conductivity of the CdS film. Hall probe data shows the resistivity of the films was in the order of 103 Ωcm. Observed data signifies its future use in the many optoelectronics devices.

  7. CdS loaded on coal based activated carbon nanofibers with enhanced photocatalytic property

    Science.gov (United States)

    Guo, Jixi; Guo, Mingxi; Jia, Dianzeng; Song, Xianli; Tong, Fenglian

    2016-08-01

    The coal based activated carbon nanofibers (CBACFs) were prepared by electrospinning a mixture of polyacrylonitrile (PAN) and acid treated coal. Cadmium sulfide (CdS) nanoparticles loaded on CBACFs were fabricated by solvothermal method. The obtained samples were characterized by FESEM, TEM, and XRD. The results reveal that the CdS nanoparticles are homogeneously dispersed on the surfaces of CBACFs. The CdS/CBACFs nanocomposites exhibited higher photoactivity for photodegradation of methyl blue (MB) under visible light irradiation than pure CdS nanoparticles. CBACFs can be used as low cost support materials for the preparation of nanocomposites with high photocatalytic activity.

  8. GBParsy: A GenBank flatfile parser library with high speed

    Directory of Open Access Journals (Sweden)

    Kim Yeon-Ki

    2008-07-01

    Full Text Available Abstract Background GenBank flatfile (GBF format is one of the most popular sequence file formats because of its detailed sequence features and ease of readability. To use the data in the file by a computer, a parsing process is required and is performed according to a given grammar for the sequence and the description in a GBF. Currently, several parser libraries for the GBF have been developed. However, with the accumulation of DNA sequence information from eukaryotic chromosomes, parsing a eukaryotic genome sequence with these libraries inevitably takes a long time, due to the large GBF file and its correspondingly large genomic nucleotide sequence and related feature information. Thus, there is significant need to develop a parsing program with high speed and efficient use of system memory. Results We developed a library, GBParsy, which was C language-based and parses GBF files. The parsing speed was maximized by using content-specified functions in place of regular expressions that are flexible but slow. In addition, we optimized an algorithm related to memory usage so that it also increased parsing performance and efficiency of memory usage. GBParsy is at least 5 - 100× faster than current parsers in benchmark tests. Conclusion GBParsy is estimated to extract annotated information from almost 100 Mb of a GenBank flatfile for chromosomal sequence information within a second. Thus, it should be used for a variety of applications such as on-time visualization of a genome at a web site.

  9. Preparation of flower-like CdS with SDBS as surfactant by hydrothermal method and its optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yongqian, E-mail: cugwyq@126.com [Faculty of Material Science and Chemistry, China University of Geosciences, Wuhan 430074 (China); Yang, Xiande; Ma, Qun; Kong, Junhan; Jia, Hanxiang; Wang, Zhengshu [Faculty of Material Science and Chemistry, China University of Geosciences, Wuhan 430074 (China); Yu, Meihua [School of Materials Science and Engineering, Guangxi University, Nanning 530004 (China)

    2015-06-15

    Graphical abstract: FESEM image of the CdS obtained by 0.01 mol Cd(NO{sub 3}){sub 2}·4H{sub 2}O, 0.03 mol thiourea and 0.5 g SDBS at 160 °C for 24 h. - Highlights: • The role of SDBS is to assemble CdS crystals together to form flower-like structures. • Both reaction time and temperature affect the morphology of flower-like structures. • The growth mechanism of flower-like structures is reasonable, clear and concise. • Its optical energy band gap is 2.50 eV, and it has absorption in visible region. • PL result of flower-like structures shows the max emission wavelength is 508.6 nm. - Abstract: In this article, the flower-like CdS have been prepared by hydrothermal method with thiourea as sulfur source and SDBS as surfactant. The effects of different experimental conditions on the morphology of CdS have been investigated. The performances of CdS have been analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), room temperature photoluminescence (PL) and UV–vis. The result of XRD indicates that CdS we prepared are highly crystallized, which are of hexagonal phase. The FE-SEM results indicate that the main role of SDBS is to make the CdS crystals assemble together to form the flower-like structures, and the reaction time affects the morphology of CdS, and the suitable reaction temperature is 160 °C. Its optical energy band gap is observed at 2.50 eV. The fluorescence spectrum shows that the flower-like CdS have a broad absorption peak and the max emission wavelength is 508.6 nm. The growth mechanism for the formation of CdS with flower-like structures is also described.

  10. Hydrothermal synthesis of CdS nanoparticle/functionalized graphene sheet nanocomposites for visible-light photocatalytic degradation of methyl orange

    International Nuclear Information System (INIS)

    Yan, Shancheng; Wang, Bojun; Shi, Yi; Yang, Fan; Hu, Dong; Xu, Xin; Wu, Jiansheng

    2013-01-01

    CdS nanoparticle/functionalized graphene sheet (CdS NP/FGS) nanocomposites were successfully prepared in a one-step hydrothermal synthesis route. The samples were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, photoluminescence spectroscopy, and Raman spectroscopy. In addition, the photocatalytic performance of CdS NP/FGS composites and pure CdS in the degradation of methyl orange (MO) was examined using visible light. Results show that the addition of FGS can enhance the photocatalytic performance of CdS NP/FGS composites with a maximum degradation efficiency of 98.1% under visible light irradiation as compared with pure CdS (60.1%). This finding can be attributed to three reasons. First is the strong redox ability of CdS in the nanocomposite with smaller crystal size. Second is the increase in specific surface area for more adsorbed MO. Third is the reduction in electron–hole pair recombination with the introduction of FGS. Based on their high photocatalytic activity, the CdS NP/FGS composites can be expected to be a practical visible light photocatalyst.

  11. Hydrothermal synthesis of CdS nanoparticle/functionalized graphene sheet nanocomposites for visible-light photocatalytic degradation of methyl orange

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Shancheng, E-mail: yansc@njupt.edu.cn [School of Geography and Biological Information, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China); National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Wang, Bojun [School of Geography and Biological Information, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China); Shi, Yi [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Yang, Fan; Hu, Dong; Xu, Xin; Wu, Jiansheng [School of Geography and Biological Information, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China)

    2013-11-15

    CdS nanoparticle/functionalized graphene sheet (CdS NP/FGS) nanocomposites were successfully prepared in a one-step hydrothermal synthesis route. The samples were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, photoluminescence spectroscopy, and Raman spectroscopy. In addition, the photocatalytic performance of CdS NP/FGS composites and pure CdS in the degradation of methyl orange (MO) was examined using visible light. Results show that the addition of FGS can enhance the photocatalytic performance of CdS NP/FGS composites with a maximum degradation efficiency of 98.1% under visible light irradiation as compared with pure CdS (60.1%). This finding can be attributed to three reasons. First is the strong redox ability of CdS in the nanocomposite with smaller crystal size. Second is the increase in specific surface area for more adsorbed MO. Third is the reduction in electron–hole pair recombination with the introduction of FGS. Based on their high photocatalytic activity, the CdS NP/FGS composites can be expected to be a practical visible light photocatalyst.

  12. Formation of CdS nanoparticles using starch as capping agent

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, P. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-IPN, Legaria 694, Col. Irrigacion 11500, Mexico D.F. (Mexico); Munoz-Aguirre, N. [Seccion de Estudios de Posgrado e Investigacion, ESIME-IPN Azcapotzalco, Av. Las Granjas 682, Col. Santa Catarina, 02550 Mexico D.F. (Mexico); Martinez, E. San-Martin [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada-IPN, Legaria 694, Col. Irrigacion 11500, Mexico D.F. (Mexico); Seccion de Estudios de Posgrado e Investigacion, ESIME-IPN Azcapotzalco, Av. Las Granjas 682, Col. Santa Catarina, 02550 Mexico D.F. (Mexico); Departamento de Fisica, CINVESTAV-IPN, Apartado Postal 14-740, 07000 Mexico D.F. (Mexico); Gonzalez, G. [Departamento de Fisica, CINVESTAV-IPN, Apartado Postal 14-740, 07000 Mexico D.F. (Mexico)], E-mail: bato@fis.cinvestav.mx; Zelaya, O.; Mendoza, J. [Departamento de Fisica, CINVESTAV-IPN, Apartado Postal 14-740, 07000 Mexico D.F. (Mexico)

    2008-11-30

    CdS nanoparticles have been synthesized using starch as capping agent in aqueous solution. The morphology and crystalline structure of such samples were measured by high-resolution transmission electron microscopy and X-ray diffraction, respectively. The average grain size of the nanoparticles determined by these techniques was of the order of 5 nm. Photoluminescence of CdS nanoparticles shows a strong emission peak below to the band gap bulk semiconductor attributed to center trap states, also the broadening peak was interpreted in terms of electron-phonon interaction.

  13. ORFer--retrieval of protein sequences and open reading frames from GenBank and storage into relational databases or text files.

    Science.gov (United States)

    Büssow, Konrad; Hoffmann, Steve; Sievert, Volker

    2002-12-19

    Functional genomics involves the parallel experimentation with large sets of proteins. This requires management of large sets of open reading frames as a prerequisite of the cloning and recombinant expression of these proteins. A Java program was developed for retrieval of protein and nucleic acid sequences and annotations from NCBI GenBank, using the XML sequence format. Annotations retrieved by ORFer include sequence name, organism and also the completeness of the sequence. The program has a graphical user interface, although it can be used in a non-interactive mode. For protein sequences, the program also extracts the open reading frame sequence, if available, and checks its correct translation. ORFer accepts user input in the form of single or lists of GenBank GI identifiers or accession numbers. It can be used to extract complete sets of open reading frames and protein sequences from any kind of GenBank sequence entry, including complete genomes or chromosomes. Sequences are either stored with their features in a relational database or can be exported as text files in Fasta or tabulator delimited format. The ORFer program is freely available at http://www.proteinstrukturfabrik.de/orfer. The ORFer program allows for fast retrieval of DNA sequences, protein sequences and their open reading frames and sequence annotations from GenBank. Furthermore, storage of sequences and features in a relational database is supported. Such a database can supplement a laboratory information system (LIMS) with appropriate sequence information.

  14. search GenBank: interactive orchestration and ad-hoc choreography of Web services in the exploration of the biomedical resources of the National Center For Biotechnology Information.

    Science.gov (United States)

    Mrozek, Dariusz; Małysiak-Mrozek, Bożena; Siążnik, Artur

    2013-03-01

    Due to the growing number of biomedical entries in data repositories of the National Center for Biotechnology Information (NCBI), it is difficult to collect, manage and process all of these entries in one place by third-party software developers without significant investment in hardware and software infrastructure, its maintenance and administration. Web services allow development of software applications that integrate in one place the functionality and processing logic of distributed software components, without integrating the components themselves and without integrating the resources to which they have access. This is achieved by appropriate orchestration or choreography of available Web services and their shared functions. After the successful application of Web services in the business sector, this technology can now be used to build composite software tools that are oriented towards biomedical data processing. We have developed a new tool for efficient and dynamic data exploration in GenBank and other NCBI databases. A dedicated search GenBank system makes use of NCBI Web services and a package of Entrez Programming Utilities (eUtils) in order to provide extended searching capabilities in NCBI data repositories. In search GenBank users can use one of the three exploration paths: simple data searching based on the specified user's query, advanced data searching based on the specified user's query, and advanced data exploration with the use of macros. search GenBank orchestrates calls of particular tools available through the NCBI Web service providing requested functionality, while users interactively browse selected records in search GenBank and traverse between NCBI databases using available links. On the other hand, by building macros in the advanced data exploration mode, users create choreographies of eUtils calls, which can lead to the automatic discovery of related data in the specified databases. search GenBank extends standard capabilities of the

  15. Photovoltaic performance enhancement of CdS quantum dot-sensitized TiO{sub 2} photoanodes with plasmonic gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Aiping, E-mail: liuaiping1979@gmail.com [Center for Optoelectronics Materials and Devices, Zhejiang Sci-Tech University, Hangzhou 310018 (China); State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Ren, Qinghua; Zhao, Ming; Xu, Tao; Yuan, Ming; Zhao, Tingyu [Center for Optoelectronics Materials and Devices, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Tang, Weihua [State Key Laboratory of Information Photonics and Optical Communication, Beijing University Posts and Telecommunications, Beijing 100876 (China)

    2014-03-15

    Highlights: • CdS QD-sensitized TiO{sub 2} porous photoanode with plasmonic gold. • A prominent light absorption enhancement of hybrid was attained by gold plasmon. • The photovoltaic response of hybrid was tunable by CdS amount. • The Au/TiO{sub 2}/CdS hybrid had a potential application in energy conversion devices. -- Abstract: The CdS quantum dot-sensitized TiO{sub 2} films with plasmonic gold nanoparticles were designed as photoanodes by the electrodeposition of gold combined with the “successive ionic layer adsorption and reaction” (SILAR) method for CdS deposition on porous TiO{sub 2} films. A prominent enhancement in light absorption of Au/TiO{sub 2}/CdS hybrid was attained by efficient light scattering of gold plasmons as sub-wavelength antennas and concentrators. The photogenerated electron formed in the near-surface region of TiO{sub 2} and CdS were facilitated to transfer to the plasmonic gold, resulting in the enhancement of photocurrent and incident photon-to-current conversion efficiency of hybrid photoanode upon photoirradiation. Furthermore, the photovoltaic response of hybrid was highly tunable with respect to the number of SILAR cycles applied to deposit CdS. The thicker absorber layer with less porous structure and larger CdS crystals might limit the electrolyte diffusion into the hybrid electrode and impose a barrier for electron tunneling and transferring. The highly versatile and tunable properties of Au/TiO{sub 2}/CdS photoanodes demonstrated their potential application in energy conversion devices.

  16. Size-dependent photodegradation of CdS particles deposited onto TiO{sub 2} mesoporous films by SILAR method

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Rasin; Will, Geoffrey; Bell, John; Wang Hongxia, E-mail: hx.wang@qut.edu.au [Queensland University of Technology, School of Chemistry, Physics and Mechanical Engineering (Australia)

    2012-09-15

    The particle size, size distribution and photostability of CdS nanoparticles incorporated onto mesoporous TiO{sub 2} films by a successive ionic layer adsorption and reaction (SILAR) method were investigated by Raman spectroscopy, UV-Visible spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). High-resolution TEM indicated that the synthesized CdS particles were hexagonal phase and the particle sizes were less than 5 nm for up to nine SILAR deposition cycles. Quantum size effect was found with the CdS-sensitized TiO{sub 2} films prepared with up to nine SILAR cycles. The band gap of CdS nanoparticles decreased from 2.65 to 2.37 eV with the increase of the SILAR cycles from 1 to 11. The investigation of the stability of the CdS/TiO{sub 2} films in air under illumination (440.6 {mu}W/cm{sup 2}) showed that the photodegradation rate was up to 85 % per day for the sample prepared with three SILAR cycles. XPS analysis indicated that the photodegradation was due to the oxidation of CdS, leading to the transformation from sulphide to sulphate (CdSO{sub 4}). Furthermore, the degradation rate was strongly dependent upon the particle size of CdS. Smaller particles showed faster degradation rate. The size-dependent photo-induced oxidization was rationalized with the variation of size-dependent distribution of surface atoms of CdS particles. Molecular dynamics-based theoretical calculation has indicated that the surface sulphide anion of a large CdS particle such as CdS made with 11 cycles (CdS Multiplication-Sign 11, average particle size = 5.6 nm) accounts for 9.6 % of the material whereas this value is increased to 19.2 % for (CdS Multiplication-Sign 3)-based smaller particles (average particle size = 2.7 nm). The photostability of CdS nanoparticles was significantly enhanced when coated with ZnS particles deposited with four SILAR cycles. The growth mechanism of ZnS upon CdS nanoparticles was discussed.

  17. Biosynthesis of CdS nanoparticles: A fluorescent sensor for sulfate-reducing bacteria detection.

    Science.gov (United States)

    Qi, Peng; Zhang, Dun; Zeng, Yan; Wan, Yi

    2016-01-15

    CdS nanoparticles were synthesized with an environmentally friendly method by taking advantage of the characteristic metabolic process of sulfate-reducing bacteria (SRB), and used as fluorescence labels for SRB detection. The presence of CdS nanoparticles was observed within and immediately surrounded bacterial cells, indicating CdS nanoparticles were synthesized both intracellularly and extracellularly. Moreover, fluorescent properties of microbial synthesized CdS nanoparticles were evaluated for SRB detection, and a linear relationship between fluorescence intensity and the logarithm of bacterial concentration was obtained in the range of from 1.0×10(2) to 1.0×10(7)cfu mL(-1). The proposed SRB detection method avoided the use of biological bio-recognition elements which are easy to lose their specific recognizing abilities, and the bacterial detection time was greatly shortened compared with the widely used MPN method which would take up to 15 days to accomplish the detection process. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Synthesis of CdS nanocrystals with different morphologies via an ultraviolet irradiation route

    International Nuclear Information System (INIS)

    Yao Suwei; Han Yuxin; Liu Weixing; Zhang Weiguo; Wang Hongzhi

    2007-01-01

    A simple ultraviolet photochemical reduction synthetic approach to preparing CdS nanocrystals with different morphologies is described. Sodium dodecyl sulfate (SDS) was used as soft template for the chemical synthesis of CdS nanocrystals in a mixture solution at room temperature. It was found that the magnetic force stirring and the volume proportions of C 2 H 5 OH and H 2 O had marked influences on the morphology of CdS nanocrystals (such as spherical, acicular-like, rod-like and worm-like shapes). The formation of CdS is via precipitation of Cd 2+ ions with the homogeneously released S 2- ions from decomposition of thioacetamide under ultraviolet irradiation source. X-ray diffraction (XRD), scanning electron microscopy (SEM) and the ultraviolet-visible (UV-vis) absorption spectra were employed to characterize the products. This novel method is expected to produce various semiconductor nanocrystals with potential applications in the fields of materials science and photovoltaic cells, etc

  19. Loose-fit polypseudorotaxanes constructed from γ-CDs and PHEMA-PPG-PEG-PPG-PHEMA

    Directory of Open Access Journals (Sweden)

    Tao Kong

    2014-10-01

    Full Text Available A pentablock copolymer was prepared via the atom transfer radical polymerization of 2-hydroxyethyl methacrylate (HEMA initiated by 2-bromoisobutyryl end-capped PPO-PEO-PPO as a macroinitiator in DMF. Attaching PHEMA blocks altered the self-assembly process of the pentablock copolymer with γ-CDs in aqueous solution. Before attaching the PHEMA, the macroinitiator was preferentially bent to pass through the inner cavity of γ-CDs to give rise to tight-fit double-chain stranded polypseudorotaxanes (PPRs. After attaching the PHEMA, the resulting pentablock copolymer was single-chain stranded into the interior of γ-CDs to form more stable, loose-fit PPRs. The results of 1H NMR, WXRD, DSC, TGA, 13C CP/MAS NMR and FTIR analyses indicated that γ-CDs can accommodate and slip over PHEMA blocks to randomly distribute along the entire pentablock copolymer chain. This results in unique, single-chain stranded PPRs showing no characteristic channel-type crystal structure.

  20. Surface modification effects on defect-related photoluminescence in colloidal CdS quantum dots.

    Science.gov (United States)

    Lee, TaeGi; Shimura, Kunio; Kim, DaeGwi

    2018-05-03

    We investigated the effects of surface modification on the defect-related photoluminescence (PL) band in colloidal CdS quantum dots (QDs). A size-selective photoetching process and a surface modification technique with a Cd(OH)2 layer enabled the preparation of size-controlled CdS QDs with high PL efficiency. The Stokes shift of the defect-related PL band before and after the surface modification was ∼1.0 eV and ∼0.63 eV, respectively. This difference in the Stokes shifts suggests that the origin of the defect-related PL band was changed by the surface modification. Analysis by X-ray photoelectron spectroscopy revealed that the surface of the CdS QDs before and after the surface modification was S rich and Cd rich, respectively. These results suggest that Cd-vacancy acceptors and S-vacancy donors affect PL processes in CdS QDs before and after the surface modification, respectively.

  1. Synthesis of uniform CdS nanowires in high yield and its single nanowire electrical property

    International Nuclear Information System (INIS)

    Yan Shancheng; Sun Litao; Qu Peng; Huang Ninping; Song Yinchen; Xiao Zhongdang

    2009-01-01

    Large-scale high quality CdS nanowires with uniform diameter were synthesized by using a rapid and simple solvothermal route. Field emission scan electron microscopy (FESEM) and transmission electron microscopy (TEM) images show that the CdS nanowires have diameter of about 26 nm and length up to several micrometres. High resolution TEM (HRTEM) study indicates the single-crystalline nature of CdS nanowires with an oriented growth along the c-axis direction. The optical properties of the products were characterized by UV-vis absorption spectra, photoluminescence spectra and Raman spectra. The resistivity, electron concentration and electron mobility of single NW are calculated by fitting the symmetric I-V curves measured on single NW by the metal-semiconductor-metal model based on thermionic field emission theory. - Graphical abstract: Large-scale high quality CdS nanowires (NWs) with uniform diameter were synthesized by using a rapid and simple solvothermal route. The reaction time is reduced to 2 h, comparing to other synthesis which needed long reaction time up to 12 h. In addition, the as-prepared CdS nanowires have more uniform diameter and high yield. More importantly, the I-V curve of present single CdS nanowire has a good symmetric characteristic as expected by the theory.

  2. Solvothermally synthesized europium-doped CdS nanorods: applications as phosphors

    International Nuclear Information System (INIS)

    Kumar, Sunil; Jindal, Zinki; Kumari, Nitu; Verma, Narendra Kumar

    2011-01-01

    To exploit the photoluminescent behavior of CdS at nanoscale with different doping concentration of europium—a rare earth element, we report the synthesis of Eu-doped CdS nanorods by using low temperature solvothermal process by using ethylenediamine. The outcomes can have future applications as phosphors, photovoltaic cells, lasers, light emitting diodes, bio-imaging, and sensors. The doping was confirmed by electron dispersive spectroscopy supported by X-ray diffraction. From scanning electron microscopy and transmission electron microscopy analysis it was observed that the average diameter of the Cd 1−x Eu x S nanorods is about 10–12 nm having lengths in the range of 50–100 nm. UV–Visible spectroscopy study was carried out to determine the band gap of the nanorods and the absorbance peaks showed blue shift with respect to the bulk CdS. The blue shift was also observed as the doping concentration of Eu increases. From photoluminescence (PL) studies at λ ex = 450 nm, peaks at 528 and 540 nm were observed due to CdS, peak at 570 nm is due to defects related transitions, while the peak at 613 nm is due to Eu. As the doping concentration of Eu is increased the intensity of the luminescent peak at 613 nm is increased. Thermogravimetric analysis showed the nanorods are thermally stable up to 300 °C. The traces of impurities adsorbed on the nanorods were confirmed by Fourier transform infrared spectroscopy.

  3. A study of size dependent structure, morphology and luminescence behavior of CdS films on Si substrate

    International Nuclear Information System (INIS)

    Kaushik, Diksha; Singh, Ragini Raj; Sharma, Madhulika; Gupta, D.K.; Lalla, N.P.; Pandey, R.K.

    2007-01-01

    Size tunable cadmium sulfide (CdS) films deposited by a dip coating technique on silicon (100) and indium tin oxide/glass substrates have been characterized using X-ray diffraction, X-ray reflectivity, transmission electron microscopy, atomic force microscopy and photoluminescence spectroscopy. The structural characterization indicated growth of an oriented phase of cadmium sulfide. Transmission electron microscopy used to calculate the particle size indicated narrow size dispersion. The tendency of nanocrystalline CdS films to form ordered clusters of CdS quantum dots on silicon (100) substrate has been revealed by morphological studies using atomic force microscopy. The photoluminescence emission spectroscopy of the cadmium sulfide films has also been investigated. It is shown that the nanocrystalline CdS exhibit intense photoluminescence as compared to the large grained polycrystalline CdS films. The effect of quantum confinement also manifested as a blue shift of photoluminescence emission. It is shown that the observed photoluminescence behavior of CdS is substantially enhanced when the nanocrystallites are assembled on silicon (100) substrate

  4. Effect of protic solvents on CdS thin films prepared by chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Pin-Chuan, E-mail: pcyao@mail.dyu.edu.tw; Chen, Chun-Yu

    2015-03-31

    In this study, cadmium sulfide (CdS) thin films are grown on glass substrates by chemical bath deposition (CBD) in an aqueous bath containing 10–20 vol.% alcohol. The roles of ethanol as a protic solvent that substantially improves the quality of films are explored extensively. The deposited films in an alcohol bath are found to be more compact and smoother with smaller CdS grains. The X-ray diffractograms of the samples confirm that all films were polycrystalline with mixed wurtzite (hexagonal) and zinkblende (cubic) phases. Raman spectra indicate that, for a film deposited in an alcohol bath, the position of 1LO is closer to the value for single crystal CdS, indicating that these films have a high degree of crystallinity. The as-deposited CdS thin films in a 10 vol.% alcohol bath were found to have the highest visible transmittance of 81.9%. XPS analysis reveals a stronger signal of C1s for samples deposited in the alcohol baths, indicating that there are more carbonaceous residues on the films with protic solvent than on the films with water. A higher XPS S/Cd atomic ratio for films deposited in an alcohol bath indicates that undesirable surface reactions (leading to sulfur containing compounds other than CdS) occur less frequently over the substrates. - Highlights: • Study of CBD-CdS films grown in an alcohol-containing aqueous bath is reported. • The deposited films in an alcohol bath are more compact with smaller CdS grains. • Raman spectra show that in an alcohol bath, the CdS film has a better crystallinity. • XPS reveals more carbon residues remain on the films deposited using alcohol bath. • In an alcohol bath, the undesirable surface reactions with Cd ions were hindered.

  5. ORF Alignment: cds [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available cds gnl|CMER >1a320 1 85 35 119 3e-17 ... gb|AAK39926.1| plastidal 30S ribosomal prot...ein S15 [Guillardia theta] pir||G90099 ... plastidal 30S ribosomal protein S15 [imported] - ... ... ... Guillardia theta nucleomorph ref|NP_113370.1| plastidal ... 30S ribosomal protein S15 [Guillardia t

  6. Self-assembly of tetrapod-shaped CdS nanostructures into 3D networks by a transverse growth process

    International Nuclear Information System (INIS)

    Fu Xiuli; Li Dan; Zhang Lei; Xiao Jinghua; Li Jiangyan; Peng Zhijian; Fang Zheyu

    2011-01-01

    Spontaneous formation of 3D tetrapod-shaped CdS nanostructure networks has been achieved for the first time by vapor diffusion-deposition growth from CdS powders. The growth mechanism of the hexagonal and preferentially oriented CdS tetrapod-shaped nanostructures is a combination of the classic vapor-liquid-solid and vapor-solid processes, and the formation of a 3D network results from the spontaneous growths along the longitudinal and across the axial directions of the primarily formed CdS nanorods. Micro-photoluminescence measurements and near-field scanning optical microscopy investigations show that the synthesized CdS tetrapod networks have an excellent luminescence property and can be used as an optical waveguide cavities in which the guided light can be extremely confined.

  7. Effect of the sulfur and fluorine concentration on physical properties of CdS films grown by chemical bath deposition

    Directory of Open Access Journals (Sweden)

    K.E. Nieto-Zepeda

    Full Text Available Undoped and F-doped CdS thin films were grown on glass slides by chemical bath deposition using thiourea, cadmium acetate and ammonium fluoride as sulfur, cadmium, and fluorine sources, respectively. Undoped CdS films were deposited varying the concentration of thiourea. Once the optimal thiourea concentration was determined, based on the crystalline quality of the samples, this concentration was maintained and ammonium fluoride was added at different concentrations in order to explore the effect of the F nominal concentration on properties of CdS films. Undoped and F-doped CdS films were characterized by X-ray diffraction, UV–Vis, room temperature photoluminescence, and four probe resistivity measurements. Results showed highly transparent F-doped CdS films with strong PL and low resistivity were obtained. Keywords: CdS films, F-doped CdS films, Chemical bath deposition, Optical properties, Room temperature photoluminescence

  8. Luminescence in Mn-doped CdS nanocrystals

    Indian Academy of Sciences (India)

    Wintec

    and the Mn d levels occur at two different energies, allowed us to study the PL lifetime decay behaviour of both kinds of .... seen from the XRD analysis, the size of the nanocrystals .... levels couple to the CdS electronic states and the excited.

  9. Tau mRNA 3'UTR-to-CDS ratio is increased in Alzheimer disease.

    Science.gov (United States)

    García-Escudero, Vega; Gargini, Ricardo; Martín-Maestro, Patricia; García, Esther; García-Escudero, Ramón; Avila, Jesús

    2017-08-10

    Neurons frequently show an imbalance in expression of the 3' untranslated region (3'UTR) relative to the coding DNA sequence (CDS) region of mature messenger RNAs (mRNA). The ratio varies among different cells or parts of the brain. The Map2 protein levels per cell depend on the 3'UTR-to-CDS ratio rather than the total mRNA amount, which suggests powerful regulation of protein expression by 3'UTR sequences. Here we found that MAPT (the microtubule-associated protein tau gene) 3'UTR levels are particularly high with respect to other genes; indeed, the 3'UTR-to-CDS ratio of MAPT is balanced in healthy brain in mouse and human. The tau protein accumulates in Alzheimer diseased brain. We nonetheless observed that the levels of RNA encoding MAPT/tau were diminished in these patients' brains. To explain this apparently contradictory result, we studied MAPT mRNA stoichiometry in coding and non-coding regions, and found that the 3'UTR-to-CDS ratio was higher in the hippocampus of Alzheimer disease patients, with higher tau protein but lower total mRNA levels. Our data indicate that changes in the 3'UTR-to-CDS ratio have a regulatory role in the disease. Future research should thus consider not only mRNA levels, but also the ratios between coding and non-coding regions. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Radiative recombination process of high density excitons in CdS crystals

    Energy Technology Data Exchange (ETDEWEB)

    Dneprovskij, V.S.; Klimov, V.I.; Martynenko, E.D.; Stadnik, V.A.

    1983-11-01

    The behaviour of the P-, E-, L- and Q-lines of luminescence in CdS is compared with calculated results for the processes of exciton-exciton scattering, exciton-electron scattering, annihilation of equilibrium electron-hole fluid (EHF), annihilation of electron-hole plasma (processes of amplification and reabsorption are taken into account). The comparison permitted to determine parameters of high density exciton gas and EHF. Spectral-kinetic properties of generation are investigated, and amplification factor in CdS is estimated.

  11. Study on the fluorescence resonance energy transfer between CdS quantum dots and Eosin Y.

    Science.gov (United States)

    Yan, Zhengyu; Zhang, Zhengwei; Yu, Yan; Chen, Jianqiu

    2015-03-01

    Water-soluble CdS quantum dots (QDs) were prepared using mercaptoacetic acid (TGA) as the stabilizer in an aqueous system. A fluorescence resonance energy transfer (FRET) system was constructed between water-soluble CdS QDs (donor) and Eosin Y (acceptor). Several factors that impacted the fluorescence spectra of the FRET system, such as pH (3.05-10.10), concentration of Eosin Y (2-80 mg/L) and concentration of CdS QDs (2-80 mg/L), were investigated and refined. Donor-to-acceptor ratios, the energy transfer efficiency (E) and the distance (r) between CdS QDs and Eosin Y were obtained. The results showed that a FRET system could be established between water-soluble CdS QDs and Eosin Y at pH 5.0; donor-to-acceptor ratios demonstrated a 1: 8 proportion of complexes; the energy transfer efficiency (E) and the distance (r) between the QDs and Eosin Y were 20.07% and 4.36 nm,respectively. Copyright © 2014 John Wiley & Sons, Ltd.

  12. Schottky junction photovoltaic devices based on CdS single nanobelts.

    Science.gov (United States)

    Ye, Y; Dai, L; Wu, P C; Liu, C; Sun, T; Ma, R M; Qin, G G

    2009-09-16

    Schottky junction photovoltaic (PV) devices were fabricated on single CdS nanobelts (NBs). Au was used as the Schottky contact, and In/Au was used as the ohmic contact to CdS NB. Typically, the Schottky junction exhibits a well-defined rectifying behavior in the dark with a rectification ratio greater than 10(3) at +/- 0.3 V; and the PV device exhibits a clear PV behavior with an open circuit photovoltage of about 0.16 V, a short circuit current of about 23.8 pA, a maximum output power of about 1.6 pW, and a fill factor of 42%. Moreover, the output power can be multiplied by connecting two or more of the Schottky junction PV devices, made on a single CdS NB, in parallel or in series. This study demonstrates that the 1D Schottky junction PV devices, which have the merits of low cost, easy fabrication and material universality, can be an important candidate for power sources in nano-optoelectronic systems.

  13. Psychometric testing of the modified Care Dependency Scale (Neuro-CDS).

    Science.gov (United States)

    Piredda, Michela; Biagioli, Valentina; Gambale, Giulia; Porcelli, Elisa; Barbaranelli, Claudio; Palese, Alvisa; De Marinis, Maria Grazia

    2016-01-01

    Effective measures of nursing care dependency in neurorehabilitation are warranted to plan nursing interventions to help patients avoid increasing dependency. The Care Dependency Scale (CDS) is a theory-based, comprehensive tool to evaluate functional disability. This study aimed to modify the CDS for neurological and neurorehabilitation patients (Neuro-CDS) and to test its psychometric properties in adult neurorehabilitation inpatients. Exploratory factor analysis (EFA) was performed using a Maximum Likelihood robust (MLR) estimator. The Barthel Index (BI) was used to evaluate concurrent validity. Stability was measured using the Intra-class Correlation Coefficient (ICC). The sample included 124 patients (mean age = 69.7 years, 54% male). The EFA revealed a two-factor structure with good fit indexes, Factor 1 (Physical care dependence) loaded by 11 items and Factor 2 (Psycho-social care dependence) loaded by 4 items. The correlation between factors was 0.61. Correlations between Factor 1 and the BI and between Factor 2 and the BI were r = 0.843 and r = 0.677, respectively (p dependence in neurorehabilitation patients as a basis for individualized and holistic care.

  14. Effect of temperature, precursor concentration and capping group on the shape of Cds nanoparticles

    CSIR Research Space (South Africa)

    Moloto, N

    2009-01-01

    Full Text Available A novel ligand to the synthesis of nanoparticles has been employed in this study. A Tetramethylthiuram disulphide cadmium complex (abundant in sulphur atoms) was used as a single-source precursor for the synthesis of CdS nanoparticles. The CdS...

  15. EPR and photoluminescence properties of Mn2+ doped CdS nanoparticles synthesized via co-precipitation method.

    Science.gov (United States)

    Gupta, Atul K; Kripal, Ram

    2012-10-01

    The structural properties of Mn doped CdS (Mn:CdS) nanoparticles (NPs) are studied using X-ray diffraction (XRD), Transmission electron microscopy (TEM), Ultraviolet-visible (UV-vis), Photoluminescence (PL), Raman and Electron paramagnetic resonance (EPR) spectroscopy. XRD analysis shows the nanostructure with 2-4 nm of average crystallite size. The planes (110), (103) and (112) in XRD pattern distinguish the wurtzite structure of the Mn:CdS NPs. The intensity of the plane (102) increases as the doping concentration of Mn(2+) increases. UV-vis absorption spectra show blue shift as compared to bulk CdS. The optical band gap energy of Mn(2+) (0, 0.35, 0.70 and 1.35 at.%) doped CdS NPs corresponding to absorption edge are found to be 5.29, 5.28, 5.25 and 5.21 eV, respectively. The intensity of luminescence is changing with the concentration of Mn(2+) doped in CdS NPs. Raman spectra show blue shift in fundamental optical phonon mode (1LO) as well as second optical phonon mode (2LO) as compared to bulk CdS. The intensity ratio of the 2LO to 1LO modes slightly decreases as Mn(2+) concentration increases. EPR shows the existence of Mn(2+) with different local structures in CdS nanoparticles. The values of spectroscopic splitting factor (g) and hyperfine interaction constant (A) decrease as Mn(2+) concentration increases in CdS NPs. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Optimization of deposition conditions of CdS thin films using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Yücel, Ersin, E-mail: dr.ersinyucel@gmail.com [Department of Physics, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey); Güler, Nuray [Department of Physics, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey); Yücel, Yasin [Department of Chemistry, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey)

    2014-03-15

    Highlights: • Statistical methods used for optimization of CdS deposition parameters. • The morphology of the films was smooth, homogeneous and continuous. • Optimal conditions found as pH 11, stirring speed:361 rpm and deposition time: 55 min. • CdS thin film band gap value was 2.72 eV under the optimum conditions. -- Abstract: Cadmium sulfide (CdS) thin films were prepared on glass substrates by chemical bath deposition (CBD) technique under different pH, stirring speed and deposition time. Response Surface Methodology (RSM) and Central Composite Design (CCD) were used to optimization of deposition parameters of the CdS thin films. RSM and CCD were also used to understand the significance and interaction of the factors affecting the film quality. Variables were determined as pH, stirring speed and deposition time. The band gap was chosen as response in the study. Influences of the variables on the band gap and the film quality were investigated. 5-level-3-factor central composite design was employed to evaluate the effects of the deposition conditions parameters such as pH (10.2–11.8), stirring speed (132–468 rpm) and deposition time (33–67 min) on the band gap of the films. The samples were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM) and ultraviolet–visible spectroscopy (UV–vis) measurements. The optimal conditions for the deposition parameters of the CdS thin films have been found to be: pH 11, 361 of stirring speed and 55 min of deposition time. Under the optimal conditions theoretical (predicted) band gap of CdS (2.66 eV) was calculated using optimal coded values from the model and the theoretical value is good agreement with the value (2.72 eV) obtained by verification experiment.

  17. CdS nanoparticle sensitized titanium dioxide decorated graphene for enhancing visible light induced photoanode

    International Nuclear Information System (INIS)

    Yousefzadeh, S.; Faraji, M.; Nien, Y.T.; Moshfegh, A.Z.

    2014-01-01

    Highlights: • CdS nanoparticles were deposited on TiO 2 /graphene film by different SILAR cycles. • The visible light absorption increased due to graphene and CdS nanoparticles. • The highest photocurrent density was achieved for nanocomposite with 30 CdS cycles. • A mechanism has been suggested for nanocomposite photoanodes, significantly. - Abstract: CdS/TiO 2 /graphene (CTG) nanocomposite thin films were synthesized by a facile production route. The TiO 2 /graphene (TG) nanocomposite was initially fabricated by sol-gel method in such a way that TiO 2 nanoparticles loaded on graphene oxide (GO) sheet via photocatalytic process. Then, CdS nanoparticles were deposited on the TG thin film by successive ion layer adsorption and reaction process (SILAR) approach. Based on atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses, the TG thin film possessed a larger surface area as compared with the pure TiO 2 thin film due to presence of graphene sheet. UV/visible spectroscopy exhibited that visible absorption of the CTG samples increased with increasing CdS SILAR deposition cycle (n). Enhanced photocurrent response of the CTG(n) photoanodes measured as compared with the TG and T photoanodes due to good electrical conductivity and large surface area of graphene as well as the visible light-harvesting ability of CdS nanoparticles. Maximum photocurrent density of about 4.5 A/m 2 and electron life time of about 5 s was measured for the CTG(30) photoanodes

  18. CdS nanoparticle sensitized titanium dioxide decorated graphene for enhancing visible light induced photoanode

    Energy Technology Data Exchange (ETDEWEB)

    Yousefzadeh, S.; Faraji, M. [Physics Department, Sharif University of Technology, P.O. Box 11155-9161, Tehran (Iran, Islamic Republic of); Nien, Y.T. [Department of Materials Science and Engineering, National Formosa University, Taiwan (China); Moshfegh, A.Z., E-mail: moshfegh@sharif.edu [Physics Department, Sharif University of Technology, P.O. Box 11155-9161, Tehran (Iran, Islamic Republic of); Institute for Nanoscience and Nanotechnology, Sharif University of Technology, P.O. Box 14588-89694, Tehran (Iran, Islamic Republic of)

    2014-11-30

    Highlights: • CdS nanoparticles were deposited on TiO{sub 2}/graphene film by different SILAR cycles. • The visible light absorption increased due to graphene and CdS nanoparticles. • The highest photocurrent density was achieved for nanocomposite with 30 CdS cycles. • A mechanism has been suggested for nanocomposite photoanodes, significantly. - Abstract: CdS/TiO{sub 2}/graphene (CTG) nanocomposite thin films were synthesized by a facile production route. The TiO{sub 2}/graphene (TG) nanocomposite was initially fabricated by sol-gel method in such a way that TiO{sub 2} nanoparticles loaded on graphene oxide (GO) sheet via photocatalytic process. Then, CdS nanoparticles were deposited on the TG thin film by successive ion layer adsorption and reaction process (SILAR) approach. Based on atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses, the TG thin film possessed a larger surface area as compared with the pure TiO{sub 2} thin film due to presence of graphene sheet. UV/visible spectroscopy exhibited that visible absorption of the CTG samples increased with increasing CdS SILAR deposition cycle (n). Enhanced photocurrent response of the CTG(n) photoanodes measured as compared with the TG and T photoanodes due to good electrical conductivity and large surface area of graphene as well as the visible light-harvesting ability of CdS nanoparticles. Maximum photocurrent density of about 4.5 A/m{sup 2} and electron life time of about 5 s was measured for the CTG(30) photoanodes.

  19. Phase- and shape-controlled hydrothermal synthesis of CdS nanoparticles, and oriented attachment growth of its hierarchical architectures

    Science.gov (United States)

    Cao, Yali; Hu, Pengfei; Jia, Dianzeng

    2013-01-01

    Hydrothermal strategies were successfully used to control the phases and morphologies of CdS nanocrystals. In the absence of an external direction-controlling process, the hexagonal and cubic phase well-defined leaf- and flower-like CdS nanocrystals were controlled obtained via adjusting the reaction duration or the concentration of surfactant. Oriented attachment growth modes were suggested for the formation of CdS superstructures, which was clarified through the tracing of temporal evolution of CdS nanoparticles. The CdS superstructures were structured by primary building nanoparticles, and held excellent visible emission with a peak in the green regions. This strategy is very helpful for studying the phase and morphology controlled fabrication of sulfides nanocrystals.

  20. Large-scale preparation of CdS quantum dots by direct thermolysis of a single-source precursor

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhiguo; Cai Wei; Sui Jiehe [School of Material Science and Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001 (China)

    2008-01-23

    CdS quantum dots (QDs) have been synthesized on a large scale, based on the direct thermolysis of one single-source precursor (Me{sub 4}N){sub 4}[S{sub 4}Cd{sub 10}(SPh){sub 16}], in hexadecylamine (HDA). Transmission electron microscopy (TEM) observations show that the CdS QDs are well-defined, nearly spherical particles. The clear lattice fringes in high-resolution TEM (HRTEM) images confirm the crystalline nature of the QDs. The broad diffraction in the x-ray diffraction (XRD) pattern and diffuse diffraction rings of the selected-area electron diffraction (SAED) pattern are typical of nanomeric-size particles and indicative of the hexagonal phase of CdS QDs. The absorption spectra confirm quantum confinement of CdS QDs. The synthesis process for CdS QDs was investigated by ultraviolet-visible (UV-vis) absorption spectroscopy. The results demonstrate that the nucleation and growth stages were separated automatically in a homogeneous system.

  1. Synthesis and crystalline properties of CdS incorporated polyvinylidene fluoride (PVDF) composite film

    Science.gov (United States)

    Patel, Arunendra Kumar; Sunder, Aishwarya; Mishra, Shweta; Bajpai, Rakesh

    2018-05-01

    This paper gives an insight on the synthesis and crystalline properties of Polyvinylidene Fluoride (PVDF) (host matrix) composites impregnated with Cadmium Sulphide (CdS) using Dimethyl formamide (DMF) as the base, prepared by the well known solvent casting technique. The effect of doping concentration of CdS in to the PVDF matrix was studied using X-ray diffraction technique. The structural properties like crystallinity Cr, interplanar distance d, average size of the crystalline region (D), and average inter crystalline separation (R) have been estimated for the developed composite. The crystallinity index, crystallite size and inter crystalline separation is increasing with increase in the concentration of CdS in to the PVDF matrix while the interplanar distance d is decreasing.

  2. Influence of Irradiation Time on properties of CdS Nanoparticles Synthesized using Microwave Irradiation

    International Nuclear Information System (INIS)

    Nayereh Soltani; Elias SSaion; Maryam Erfani; Mohd Zobir Hussein; Robiah Yunus

    2011-01-01

    Different sizes of cadmium sulfide nanoparticles which exhibit obvious quantum confinement effect have been synthesized of cadmium chloride and thioacetamide through the simple and rapid microwave method. The properties of these CdS nanoparticles were examined with varying irradiation time from 10 to 40 min using a pulse regime. The obtained CdS particles were characterized by X-ray diffraction (XRD), transition electron microscopy (TEM) and UV-visible (UV-Vis) spectroscopy. The effects of irradiation time on the size, degree of crystallinity, yield of reaction and optical band gap of CdS nanoparticles are investigated. (author)

  3. Glycolthermal synthesis and characterization of hexagonal CdS round microparticles in flower-like clusters

    International Nuclear Information System (INIS)

    Phuruangrat, Anukorn; Ekthammathat, Nuengruethai; Thongtem, Titipun; Thongtem, Somchai

    2011-01-01

    Highlights: → CdS as one of II-VI semiconducting materials. → Lab-made Teflon-lined stainless steel autoclaves enable us to form hexagonal CdS. → By 100-200 deg. C processing, round microparticles in flower clusters were synthesized. → A promising material for multiple potential applications. - Abstract: Hexagonal CdS round microparticles in flower-like clusters were synthesized by glycolthermal reactions of CdCl 2 and thiourea as cadmium and sulphur sources in 1,2-propylene glycol (PG) at 100-200 deg. C for 10-30 h. Phase and morphology were detected using X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM, TEM). The products were pure phase of hexagonal wurtzite CdS. The quantitative elemental analysis of Cd:S ratio was detected using energy dispersive X-ray (EDX) analyzer. Raman spectrometer revealed the presence of fundamental and overtone modes at 296 and 595 cm -1 , corresponding to the strong 1LO and weak 2LO modes, respectively. Photonic properties were investigated using UV-visible and photoluminescence (PL) spectroscopy. They showed the same absorption at 493-498 nm, and emission at 431 nm due to the excitonic recombination process. A possible formation mechanism was also proposed, according to experimental results.

  4. Glycolthermal synthesis and characterization of hexagonal CdS round microparticles in flower-like clusters

    Energy Technology Data Exchange (ETDEWEB)

    Phuruangrat, Anukorn, E-mail: phuruangrat@hotmail.com [Department of Materials Science and Technology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112 (Thailand); Ekthammathat, Nuengruethai [Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thongtem, Titipun, E-mail: ttpthongtem@yahoo.com [Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thongtem, Somchai [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2011-10-13

    Highlights: > CdS as one of II-VI semiconducting materials. > Lab-made Teflon-lined stainless steel autoclaves enable us to form hexagonal CdS. > By 100-200 deg. C processing, round microparticles in flower clusters were synthesized. > A promising material for multiple potential applications. - Abstract: Hexagonal CdS round microparticles in flower-like clusters were synthesized by glycolthermal reactions of CdCl{sub 2} and thiourea as cadmium and sulphur sources in 1,2-propylene glycol (PG) at 100-200 deg. C for 10-30 h. Phase and morphology were detected using X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM, TEM). The products were pure phase of hexagonal wurtzite CdS. The quantitative elemental analysis of Cd:S ratio was detected using energy dispersive X-ray (EDX) analyzer. Raman spectrometer revealed the presence of fundamental and overtone modes at 296 and 595 cm{sup -1}, corresponding to the strong 1LO and weak 2LO modes, respectively. Photonic properties were investigated using UV-visible and photoluminescence (PL) spectroscopy. They showed the same absorption at 493-498 nm, and emission at 431 nm due to the excitonic recombination process. A possible formation mechanism was also proposed, according to experimental results.

  5. A CDO option market model on standardized CDS index tranches

    DEFF Research Database (Denmark)

    Dorn, Jochen

    We provide a market model which implies a dynamic for standardized CDS index tranche spreads. This model is useful for pricing options on tranches with future Issue Dates as well as for modeling emerging options on struc- tured credit derivatives. With the upcoming regulation of the CDS market...... in perspective, the model presented here is also an attempt to face the e ects on pricing approaches provoked by an eventual Clearing Chamber . It becomes also possible to calibrate Index Tranche Options with bespoke tenors/tranche subordination to market data obtained by more liquid Index Tranche Options...

  6. Fabrication of CDs/CdS-TiO2 ternary nano-composites for photocatalytic degradation of benzene and toluene under visible light irradiation

    Science.gov (United States)

    Wang, Meng; Hua, Jianhao; Yang, Yaling

    2018-06-01

    An efficient cadmium sulfide quantum-dots (CdS QDs) and carbon dots (CDs) modified TiO2 photocatalyst (CdS/CDs-TiO2) was successfully fabricated. The as-prepared ternary nano-composites simultaneously improved the photo-corrosion of CdS and amplified its photocatalytic activity. The introduction of CdS QDs and CDs could enhance more absorbance of light, prevent the undesirable electron/hole recombination, and promote charge separation, which was important for the continuous formation of rad OH and rad O2- radicals. When the optimal mass ratio of CdS QDs to CDs was 3:1, above 90% degradation efficiencies were achieved for benzene within 1 h and toluene in 2 h, while that of pure TiO2 (P25), CdS QDs-TiO2, CDs-TiO2 nano-composites was around 15%. Owing to the symmetric structure and conjugation of methyl with benzene ring, the degradation of toluene was more difficult than benzene to carry on. The new fabricated nano-composites showed good prospective application of cleaning up refractory pollutants and the resource utilization.

  7. An improved pyrolysis route to synthesize carbon-coated CdS quantum dots with fluorescence enhancement effect

    International Nuclear Information System (INIS)

    Zhang Kejie; Liu Xiaoheng

    2011-01-01

    Well-dispersed carbon-coated CdS (CdS-C) quantum dots were successfully prepared via the improved pyrolysis of bis(1-dodecanethiol)-cadmium(II) under nitrogen atmosphere. This simple method effectively solved the sintered problem resulted from conventional pyrolysis process. The experimental results indicated that most of the as-prepared nanoparticles displayed well-defined core-shell structures. The CdS cores with diameter of ∼5 nm exhibited hexagonal crystal phase, the carbon shells with thickness of ∼2 nm acted as a good dispersion medium to prevent CdS particles from aggregation, and together with CdS effectively formed a monodisperse CdS-Carbon nanocomposite. This composite presented a remarkable fluorescence enhancement effect, which indicated that the prepared nanoparticles might be a promising photoresponsive material or biosensor. This improved pyrolysis method might also offer a facile way to prepare other carbon-coated semiconductor nanostructures. - Graphical abstract: We demonstrated a facile approach to synthesize well-dispersed carbon-coated CdS quantum dots. The as-prepared nanoparticles presented remarkable fluorescence enhancement effect. Highlights: → Carbon-coated CdS quantum dots were synthesized by an one-step pyrolysis method. → Well-dispersed CdS-carbon nanoparticles were obtained by an acid treatment process. → As-prepared nanoparticles presented remarkable fluorescence enhancement effect.

  8. Effects of Different Doping Ratio of Cu Doped CdS on QDSCs Performance

    Directory of Open Access Journals (Sweden)

    Xiaojun Zhu

    2015-01-01

    Full Text Available We use the successive ionic layer adsorption and reaction (SILAR method for the preparation of quantum dot sensitized solar cells, to improve the performance of solar cells by doping quantum dots. We tested the UV-Vis absorption spectrum of undoped CdS QDSCs and Cu doped CdS QDSCs with different doping ratios. The doping ratios of copper were 1 : 100, 1 : 500, and 1 : 1000, respectively. The experimental results show that, under the same SILAR cycle number, Cu doped CdS quantum dot sensitized solar cells have higher open circuit voltage, short circuit current density photoelectric conversion efficiency than undoped CdS quantum dots sensitized solar cells. Refinement of Cu doping ratio are 1 : 10, 1 : 100, 1 : 200, 1 : 500, and 1 : 1000. When the proportion of Cu and CdS is 1 : 10, all the parameters of the QDSCs reach the minimum value, and, with the decrease of the proportion, the short circuit current density, open circuit voltage, and the photoelectric conversion efficiency are all increased. When proportion is 1 : 500, all parameters reach the maximum values. While with further reduction of the doping ratio of Cu, the parameters of QDSCs have a decline tendency. The results showed that, in a certain range, the lower the doping ratio of Cu, the better the performance of quantum dot sensitized solar cell.

  9. Junction formation of CuInSe2 with CdS: A comparative study of 'dry' and 'wet' interfaces

    International Nuclear Information System (INIS)

    Hunger, R.; Lebedev, M.V.; Sakurai, K.; Schulmeyer, T.; Mayer, Th.; Klein, A.; Niki, S.; Jaegermann, W.

    2007-01-01

    The junction formation of polycrystalline CuInSe 2 absorbers (CIS) with thermally evaporated CdS was investigated by high-resolution synchrotron X-ray photoelectron spectroscopy. The chemistry and electronics of the interfaces of Cd partial electrolyte treated CIS ('wet' processed) and clean, decapped CIS ('dry' processed) were compared. A valence band offset of 0.96(10) eV was determined in both cases. The Cd(Se,OH) surface layer induced by the wet Cd partial electrolyte process does not significantly modify the band alignment at the CIS/CdS heterointerface from the 'dry', vacuum-processed CIS/CdS interface. During the stepwise interface formation the energy converting capability of the CIS/CdS heterojunction was assessed by in situ surface photovoltage measurements at room temperature. The evolution of the surface photovoltage significantly differs for the 'wet' and the 'dry' interfaces and is discussed in relation to the function in solar cell devices

  10. Synthesis and characterization of TiO2/CdS core–shell nanorod arrays and their photoelectrochemical property

    International Nuclear Information System (INIS)

    Cao Chunlan; Hu Chenguo; Shen Weidong; Wang, Shuxia; Tian Yongshu; Wang Xue

    2012-01-01

    Highlights: ► TiO 2 /CdS core–shell nanorod arrays were fabricated by spin-SILAR method. ► The enhanced photocurrent was found in the TiO 2 /CdS core–shell nanorod arrays. ► The CdS coated on TiO 2 increases the e-h separation and enlarges light absorption range. - Abstract: TiO 2 /CdS core–shell nanorod arrays have been fabricated via a two-step method. Vertically aligned TiO 2 nanorod arrays (NRs) were synthesized by a facile hydrothermal method, and followed by depositing CdS nanoparticles on TiO 2 NRs by spin-coating successive ion layer adsorption and reaction (spin-SILAR) method. The surface morphology, structure, optical and photoelectrochemical behaviors of the core–shell NRs films are considered. The UV–vis absorption spectrum results suggested that the absorption peak of the TiO 2 /CdS core–shell NRs shifts from the ultraviolet region to the visible region in comparison to that of the pure TiO 2 NRs. The obviously enhanced photoelectrochemical (PEC) performances of the heterojunction NRs were found under illumination of the simulated sunlight in comparison with that of the TiO 2 NRs. The enhanced PEC performance and formation mechanism of TiO 2 /CdS core–shell NRs were discussed in detail.

  11. Effect of Ag doping on opto-electrical properties of CdS thin films for solar cell applications

    International Nuclear Information System (INIS)

    Nazir, Adnan; Toma, Andrea; Shah, Nazar Abbas; Panaro, Simone; Butt, Sajid; Sagar, Rizwan ur Rehman; Raja, Waseem; Rasool, Kamran; Maqsood, Asghari

    2014-01-01

    Highlights: • Polycrystalline CdS thin films are fabricated by means of Close Spaced Sublimation technique. • Ag is doped by simple ion-exchange technique in order to reduce resistivity of CdS thin films. • Remarkable reduction in resistivity without introducing many transparency losses. - Abstract: Cadmium sulfide (CdS) polycrystalline thin films of different thicknesses (ranging from 370 nm to 750 nm) were fabricated on corning glass substrates using Close Spaced Sublimation (CSS) technique. Optical and electrical investigation revealed that CdS thin films show an appreciable transparency (50–70% transmission) in visible range and a highly resistive behavior (10 6 Ω cm). Samples were doped by silver (Ag) at different concentrations, using ion exchange technique, in order to reduce the resistivity of CdS thin films and to improve their efficiency as a window layer for solar cell application. The doping of Ag in pure CdS thin films resulted into an increase of surface roughness and a decrease both in electrical resistivity and in transparency. By optimizing annealing parameters, we were able to properly control the optical properties of the present system. In fact, the Ag doping of pure CdS films has led to a decrease of the sample resistivity by three orders of magnitude (10 3 Ω cm) against a 20% cut in optical transmission

  12. Electroluminescent Cu-doped CdS quantum dots

    NARCIS (Netherlands)

    Stouwdam, J.W.; Janssen, R.A.J.

    2009-01-01

    Incorporating Cu-doped CdS quantum dots into a polymer host produces efficient light-emitting diodes. The Cu dopant creates a trap level that aligns with the valence band of the host, enabling the direct injection of holes into the quantum dots, which act as emitters. At low current densities, the

  13. Characterization of chemically synthesized CdS nanoparticles

    Indian Academy of Sciences (India)

    Similar to the effects of charge carriers on optical properties, confinement of optical and acoustic phonons leads to interesting changes in the phonon spectra. In the present work, we have synthesized nanoparticles of CdS using chemical precipitation technique. The crystal structure and grain size of the particles are studied ...

  14. In vitro and in vivo assessment of nanotoxicity of CdS quantum dot/aminopolysaccharide bionanoconjugates

    International Nuclear Information System (INIS)

    2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil); Department of Physiology and Biophysics, ICB, UFMG (Brazil))" data-affiliation=" (Center of Nanoscience, Nanotechnology, and Innovation-CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil); Department of Physiology and Biophysics, ICB, UFMG (Brazil))" >Carvalho, S.M. de; 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil))" data-affiliation=" (Center of Nanoscience, Nanotechnology, and Innovation-CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil))" >Mansur, A.A.P.; 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil))" data-affiliation=" (Center of Nanoscience, Nanotechnology, and Innovation-CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil))" >Mansur, H.S.; Guedes, M.I.M.C.; Lobato, Z.I.P.; Leite, M.F.

    2017-01-01

    The nanotoxicity of Cd-containing quantum dots (QDs) for biomedical applications is very controversial and not completely understood. In this study, we evaluated the cytotoxicity of surface-biofunctionalized CdS QDs with chitosan directly synthesized via aqueous route at room temperature. These core-shell CdS-chitosan nanoconjugates showed different degrees of cytotoxic responses using MTT cell proliferation assay toward three human cell cultures, human osteosarcoma cell line (SAOS), non-Hodgkin's B cell lymphoma (Toledo), and human embryonic kidney cell line (HEK293T), under three exposure times (1, 3, and 5 days) and three colloidal concentrations (10 nM, 50 nM, and 100 nM). The results clearly demonstrated that the CdS QDs, regardless to the fact that they were coated with a biocompatible aminopolysaccharide shell, induced a severe dose- and time-dependent inhibition of cell viability. In addition, the HEK293T and SAOS cell lines showed much more sensitive response compared to Toledo, which indicated that the cytotoxicity was also cell-type dependent. The exceptional resistance of Toledo cells to toxic effects of CdS nanoconjugates even at severe test conditions was assigned to specific role of B-lineage cells of the immune defense system. Remarkably, no conclusive evidence of toxicity of CdS nanoconjugates was observed in vivo using intravenous injections of CdS nanoconjugates in BALB/c mouse animal models for 30 days, but localized fluorescence was detected in ex-vivo liver tissue samples. Therefore, these results prove that there is no guarantee of “risk-free” use of CdS nanoconjugates for in vivo applications, even when functionalized with biopolymer ligands, as they can pose an excessive threat due to unpredicted and uncorrelated responses under in vitro and in vivo biological assays with highly toxic cadmium ions. - Graphical abstract: Biocompatible surface functionalization with aminopolysaccharide is not enough for assuring safe biomedical

  15. In vitro and in vivo assessment of nanotoxicity of CdS quantum dot/aminopolysaccharide bionanoconjugates

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, S.M. de [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil); Department of Physiology and Biophysics, ICB, UFMG (Brazil); Mansur, A.A.P. [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil); Mansur, H.S., E-mail: hmansur@demet.ufmg.br [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG (Brazil); Guedes, M.I.M.C.; Lobato, Z.I.P. [Department of Preventive Veterinary Medicine, Veterinary School, UFMG (Brazil); Leite, M.F. [Department of Physiology and Biophysics, ICB, UFMG (Brazil)

    2017-02-01

    The nanotoxicity of Cd-containing quantum dots (QDs) for biomedical applications is very controversial and not completely understood. In this study, we evaluated the cytotoxicity of surface-biofunctionalized CdS QDs with chitosan directly synthesized via aqueous route at room temperature. These core-shell CdS-chitosan nanoconjugates showed different degrees of cytotoxic responses using MTT cell proliferation assay toward three human cell cultures, human osteosarcoma cell line (SAOS), non-Hodgkin's B cell lymphoma (Toledo), and human embryonic kidney cell line (HEK293T), under three exposure times (1, 3, and 5 days) and three colloidal concentrations (10 nM, 50 nM, and 100 nM). The results clearly demonstrated that the CdS QDs, regardless to the fact that they were coated with a biocompatible aminopolysaccharide shell, induced a severe dose- and time-dependent inhibition of cell viability. In addition, the HEK293T and SAOS cell lines showed much more sensitive response compared to Toledo, which indicated that the cytotoxicity was also cell-type dependent. The exceptional resistance of Toledo cells to toxic effects of CdS nanoconjugates even at severe test conditions was assigned to specific role of B-lineage cells of the immune defense system. Remarkably, no conclusive evidence of toxicity of CdS nanoconjugates was observed in vivo using intravenous injections of CdS nanoconjugates in BALB/c mouse animal models for 30 days, but localized fluorescence was detected in ex-vivo liver tissue samples. Therefore, these results prove that there is no guarantee of “risk-free” use of CdS nanoconjugates for in vivo applications, even when functionalized with biopolymer ligands, as they can pose an excessive threat due to unpredicted and uncorrelated responses under in vitro and in vivo biological assays with highly toxic cadmium ions. - Graphical abstract: Biocompatible surface functionalization with aminopolysaccharide is not enough for assuring safe biomedical

  16. Planar heterojunction perovskite solar cell based on CdS electron transport layer

    KAUST Repository

    Abulikemu, Mutalifu

    2017-07-02

    We report on planar heterojunction perovskite solar cells employing a metal chalcogenide (CdS) electron transport layer with power conversion efficiency up to 10.8%. The CdS layer was deposited via solution-process chemical bath deposition at low-temperature (60°C). Pinhole-free and uniform thin films were obtained with good structural, optical and morphological properties. An optimal layer thickness of 60nm yielded an improved open-circuit voltage and fill factor compared to the standard TiO2-based solar cells. Devices showed a higher reproducibility of the results compared to TiO2-based ones. We also tested the effect of annealing temperature on the CdS film and the effect of CdCl2 treatment followed by high temperature annealing (410°C) that is expected to passivate the surface, thus eliminating eventual trap-states inducing recombination.

  17. Planar heterojunction perovskite solar cell based on CdS electron transport layer

    KAUST Repository

    Abulikemu, Mutalifu; Barbe, Jeremy; El Labban, Abdulrahman; Eid, Jessica; Del Gobbo, Silvano

    2017-01-01

    We report on planar heterojunction perovskite solar cells employing a metal chalcogenide (CdS) electron transport layer with power conversion efficiency up to 10.8%. The CdS layer was deposited via solution-process chemical bath deposition at low-temperature (60°C). Pinhole-free and uniform thin films were obtained with good structural, optical and morphological properties. An optimal layer thickness of 60nm yielded an improved open-circuit voltage and fill factor compared to the standard TiO2-based solar cells. Devices showed a higher reproducibility of the results compared to TiO2-based ones. We also tested the effect of annealing temperature on the CdS film and the effect of CdCl2 treatment followed by high temperature annealing (410°C) that is expected to passivate the surface, thus eliminating eventual trap-states inducing recombination.

  18. Enhanced Photovoltaic Properties of the Solar Cells Based on Cosensitization of CdS and Hydrogenation

    Directory of Open Access Journals (Sweden)

    Hongcai He

    2015-01-01

    Full Text Available The hydrogenated TiO2 porous nanocrystalline film is modified with CdS quantum dots by successive ionic layer adsorption and reaction (SILAR method to prepare the cosensitized TiO2 solar cells by CdS quantum dots and hydrogenation. The structure and topography of the composite photoanode film were confirmed by X-ray diffraction and scanning electron microscopy. With deposited CdS nanoparticles, UV absorption spectra of H:TiO2 photoanode film indicated a considerably enhanced absorption in the visible region. The cosensitized TiO2 solar cell by CdS quantum dots and hydrogenation presents much better photovoltaic properties than either CdS sensitized TiO2 solar cells or hydrogenated TiO2 solar cells, which displays enhanced photovoltaic performance with power conversion efficiency (η of 1.99% (Jsc=6.26 mA cm−2, Voc=0.65 V, and FF = 0.49 under full one-sun illumination. The reason for the enhanced photovoltaic performance of the novel cosensitized solar cell is primarily explained by studying the Nyquist spectrums, IPCE spectra, dark current, and photovoltaic performances.

  19. Structural and optical properties of nano-structured CdS thin films prepared by chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Rekha, E-mail: rekha.mittal07@gmail.com; Kumar, Dinesh; Chaudhary, Sujeet; Pandya, Dinesh K. [Thin Film Laboratory, Physics Department, Indian Institute of Technology Delhi, New Delhi-110016 (India)

    2016-05-06

    Cadmium sulfide (CdS) thin films have been deposited on conducting glass substrates by chemical bath deposition (CBD) technique. The effect of precursor concentration on the structural, morphological, compositional, and optical properties of the CdS films has been studied. Crystal structure of these CdS films is characterized by X-ray diffraction (XRD) and it reveals polycrystalline structure with mixture of cubic and wurtzite phases with grain size decreasing as precursor concentration is increased. Optical studies reveal that the CdS thin films have high transmittance in visible spectral region reaching 90% and the films possess direct optical band gap that decreases from 2.46 to 2.39 eV with decreasing bath concentration. Our study suggests that growth is nucleation controlled.

  20. Chemical synthesis of CdS onto TiO2 nanorods for quantum dot sensitized solar cells

    Science.gov (United States)

    Pawar, Sachin A.; Patil, Dipali S.; Lokhande, Abhishek C.; Gang, Myeng Gil; Shin, Jae Cheol; Patil, Pramod S.; Kim, Jin Hyeok

    2016-08-01

    A quantum dot sensitized solar cell (QDSSC) is fabricated using hydrothermally grown TiO2 nanorods and successive ionic layer adsorption and reaction (SILAR) deposited CdS. Surface morphology of the TiO2 films coated with different SILAR cycles of CdS is examined by Scanning Electron Microscopy which revealed aggregated CdS QDs coverage grow on increasing onto the TiO2 nanorods with respect to cycle number. Under AM 1.5G illumination, we found the TiO2/CdS QDSSC photoelectrode shows a power conversion efficiency of 1.75%, in an aqueous polysulfide electrolyte with short-circuit photocurrent density of 4.04 mA/cm2 which is higher than that of a bare TiO2 nanorods array.

  1. Structural and optical properties of nano-structured CdS thin films prepared by chemical bath deposition

    International Nuclear Information System (INIS)

    Bai, Rekha; Kumar, Dinesh; Chaudhary, Sujeet; Pandya, Dinesh K.

    2016-01-01

    Cadmium sulfide (CdS) thin films have been deposited on conducting glass substrates by chemical bath deposition (CBD) technique. The effect of precursor concentration on the structural, morphological, compositional, and optical properties of the CdS films has been studied. Crystal structure of these CdS films is characterized by X-ray diffraction (XRD) and it reveals polycrystalline structure with mixture of cubic and wurtzite phases with grain size decreasing as precursor concentration is increased. Optical studies reveal that the CdS thin films have high transmittance in visible spectral region reaching 90% and the films possess direct optical band gap that decreases from 2.46 to 2.39 eV with decreasing bath concentration. Our study suggests that growth is nucleation controlled.

  2. The structural properties of CdS deposited by chemical bath deposition and pulsed direct current magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Lisco, F., E-mail: F.Lisco@lboro.ac.uk [Centre for Renewable Energy Systems Technology (CREST), School of Electronic, Electrical and Systems Engineering, Loughborough University, Leicestershire, LE11 3TU (United Kingdom); Kaminski, P.M.; Abbas, A.; Bass, K.; Bowers, J.W.; Claudio, G. [Centre for Renewable Energy Systems Technology (CREST), School of Electronic, Electrical and Systems Engineering, Loughborough University, Leicestershire, LE11 3TU (United Kingdom); Losurdo, M. [Institute of Inorganic Methodologies and of Plasmas, IMIP-CNR, via Orabona 4, 70126 Bari (Italy); Walls, J.M. [Centre for Renewable Energy Systems Technology (CREST), School of Electronic, Electrical and Systems Engineering, Loughborough University, Leicestershire, LE11 3TU (United Kingdom)

    2015-05-01

    Cadmium sulphide (CdS) thin films were deposited by two different processes, chemical bath deposition (CBD), and pulsed DC magnetron sputtering (PDCMS) on fluorine doped-tin oxide coated glass to assess the potential advantages of the pulsed DC magnetron sputtering process. The structural, optical and morphological properties of films obtained by CBD and PDCMS were investigated using X-ray photoelectron spectroscopy, X-ray diffraction, scanning and transmission electron microscopy, spectroscopic ellipsometry and UV-Vis spectrophotometry. The as-grown films were studied and comparisons were drawn between their morphology, uniformity, crystallinity, and the deposition rate of the process. The highest crystallinity is observed for sputtered CdS thin films. The absorption in the visible wavelength increased for PDCMS CdS thin films, due to the higher density of the films. The band gap measured for the as-grown CBD-CdS is 2.38 eV compared to 2.34 eV for PDCMS-CdS, confirming the higher density of the sputtered thin film. The higher deposition rate for PDCMS is a significant advantage of this technique which has potential use for high rate and low cost manufacturing. - Highlights: • Pulsed DC magnetron sputtering (PDCMS) of CdS films • Chemical bath deposition of CdS films • Comparison between CdS thin films deposited by chemical bath and PDCMS techniques • High deposition rate deposition for PDCMS deposition • Uniform, pinhole free CdS thin films.

  3. The structural properties of CdS deposited by chemical bath deposition and pulsed direct current magnetron sputtering

    International Nuclear Information System (INIS)

    Lisco, F.; Kaminski, P.M.; Abbas, A.; Bass, K.; Bowers, J.W.; Claudio, G.; Losurdo, M.; Walls, J.M.

    2015-01-01

    Cadmium sulphide (CdS) thin films were deposited by two different processes, chemical bath deposition (CBD), and pulsed DC magnetron sputtering (PDCMS) on fluorine doped-tin oxide coated glass to assess the potential advantages of the pulsed DC magnetron sputtering process. The structural, optical and morphological properties of films obtained by CBD and PDCMS were investigated using X-ray photoelectron spectroscopy, X-ray diffraction, scanning and transmission electron microscopy, spectroscopic ellipsometry and UV-Vis spectrophotometry. The as-grown films were studied and comparisons were drawn between their morphology, uniformity, crystallinity, and the deposition rate of the process. The highest crystallinity is observed for sputtered CdS thin films. The absorption in the visible wavelength increased for PDCMS CdS thin films, due to the higher density of the films. The band gap measured for the as-grown CBD-CdS is 2.38 eV compared to 2.34 eV for PDCMS-CdS, confirming the higher density of the sputtered thin film. The higher deposition rate for PDCMS is a significant advantage of this technique which has potential use for high rate and low cost manufacturing. - Highlights: • Pulsed DC magnetron sputtering (PDCMS) of CdS films • Chemical bath deposition of CdS films • Comparison between CdS thin films deposited by chemical bath and PDCMS techniques • High deposition rate deposition for PDCMS deposition • Uniform, pinhole free CdS thin films

  4. Growth of CdS thin films on indium coated glass substrates via chemical bath deposition and subsequent air annealing

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Biswajit; Kumar, Kamlesh; Singh, Balwant Kr; Banerjee, Pushan; Das, Subrata, E-mail: neillohit@yahoo.co.in

    2014-11-30

    Graphical abstract: - Highlights: • CdS film grown on indium coated glass substrates via CBD and subsequent annealing. • Disappearance of the indium (1 1 2) peak confirms interdiffusion at 300 °C. • SIMS indicates the subsequent interdiffusion at progressively higher temperature. • Composite In–CdS layer showed lower photosensitivity compared to pure CdS. - Abstract: In the present work attempts were made to synthesize indium doped CdS films by fabricating In/CdS bilayers using CBD-CdS on vacuum evaporated In thin films and subsequent air annealing. 135 nm CdS films were grown onto 20 nm and 35 nm indium coated glass substrate employing chemical bath deposition technique. The In/CdS bilayers thus formed were subjected to heat treatment at the temperatures between 200 and 400 °C for 4 min in the muffle furnace to facilitate indium to diffuse into the CdS films. XRD pattern ascertained no noticeable shift in lattice constant implying grain boundary metal segregation, while secondary ion mass spectrometry indicated the diffusion profile of indium into CdS matrices. Mass spectrometry results showed that substantial diffusion of indium had been taken place within CdS at 400 °C. Dark and photocurrent with different illumination time were measured to ascertain the photosensitivity of pure and composite CdS films.

  5. Synthesis of poly (3-hexyl thiophene-2,5-diyl) in presence of CdS nanoparticles: microscopic and spectroscopic studies

    Energy Technology Data Exchange (ETDEWEB)

    Nicho, M. E.; Jaimes, W. [Universidad Autonoma del Estado de Morelos, Centro de Investigacion en Ingenierias y Ciencias Aplicadas, Av. Universidad 1001, Col. Chamilpa, 62209 Cuernavaca, Morelos (Mexico); Rivas A, M. E.; Quevedo L, M. A. [University of Texas at Dallas, Department of Materials Science and Engineering, 800 West Campbell Road, Richardson, Texas 75252 (United States); Hu, H., E-mail: menicho@uaem.mx [UNAM, Instituto de Energias Renovables, 62580 Temixco, Morelos (Mexico)

    2017-11-01

    In this paper, the synthesis of nano composites of poly(3-hexyl thiophene-2,5-diyl) (P3HT) and cadmium sulfide (CdS) nanoparticles are reported. CdS nanoparticles were first synthesized using chemical precipitation. Then P3HT was synthesized by direct oxidation of 3-hexyl thiophene with FeCl{sub 3} as oxidant in presence of CdS nanoparticles. The goal of this work was to investigate the effect of the CdS nanoparticles during the synthesis of P3HT. The resulting films of P3HT/CdS nano composites were investigated by Fourier Transform Infrared Spectroscopy (Ft-IR), Ultraviolet-Visible Spectroscopy (UV-Vis), X-ray diffraction, Transmission electron microscopy (Tem), Atomic force microscopy (AFM) and Scanning electron microscopy (Sem). Homogeneous distribution of CdS nanoparticles in P3HT was demonstrated by Sem, AFM and Tem. Ft-IR analysis showed interaction between CdS and the S atoms of the thiophene rings. This result, together with UV-Vis spectra and XRD pattern suggest a better arrangement of the polymer chains. It is possible that the CdS nanoparticles are coupled with the unpaired electrons of S atoms in the thiophene rings through the positive delocalized charge, resulting in a more ordered P3HT polymer matrix with embedded CdS nanoparticles. (Author)

  6. Effect of precursor concentration, temperature and capping group on the morphology of CdS nanoparticles

    CSIR Research Space (South Africa)

    Moloto, N

    2008-01-01

    Full Text Available A novel ligand to the synthesis of nanoparticles has been employed in this study. A Tetramethylthiuram disulphide cadmium complex (abundant in sulphur atoms) was used as a single-source precursor for the synthesis of CdS nanoparticles. The CdS...

  7. CdS nanobubbles and Cd-DMS nanosheets: solvothermal synthesis and formation mechanism.

    Science.gov (United States)

    Feng, Miao; Zhan, Hongbing

    2013-02-01

    CdS nanobubbles and Cd-DMS nanosheets have been prepared by a solvothermal method from a solution of Cd2+ in dimethyl sulfoxide in the absence of elemental S. A formation mechanism for the nanobubble morphology arising during the CdS nanocrystal growth has been proposed, based on the results of transmission electron microscopy and photoluminescence spectrophotometry. The correlation of the morphology with reaction time was also suggested, and may be applicable to the solvothermal synthesis of other nanomaterials.

  8. Enhanced Performance of DSSCs Based on the Insertion Energy Level of CdS Quantum Dots

    Directory of Open Access Journals (Sweden)

    Xiaoping Zou

    2014-01-01

    Full Text Available Cadmium sulfide (CdS quantum dots (QDs are assembled onto the TiO2 films by chemical bath deposition method (CBD. And the QDs size is controlled by the times of CBD cycles. They are characterized by UV-visible absorption. To avoid the photo corrosion and electrolyte corrosion, CdS and N719 are sequentially assembled onto the nanocrystalline TiO2 films to prepare a CdS/N719 cosensitized photo electrode for the dye-sensitized solar cells. In the structure of TiO2/CdS/N719 electrode, the reorganization of energy levels between CdS and N719 forms a stepwise structure of band-edge levels which is advantageous to the electron injection and hole recovery of CdS and N719 QDs. The open circuit voltage (Voc, short circuit current density (Jsc, and efficiency are increased.

  9. Synthesis and characterization of CdS nanocrystallites and OMWCNT-supported cadmium sulfide composite and their photocatalytic activity under visible light irradiation

    International Nuclear Information System (INIS)

    Pawar, Amol S.; Garje, Shivram S.; Revaprasadu, Neerish

    2016-01-01

    CdS nanocrystallites and CdS- oxidized multiwalled carbon nanotubes (OMWCNT) composite were prepared by the solvothermal decomposition of a single-source molecular precursor, [Cd(pip.dtc) 2 ] (pip.dtc = piperidine dithiocarbamate) in the presence of ethylene glycol. The as prepared CdS nanocrystallites and CdS-OMWCNT composite were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), UV-vis and Raman spectroscopy. Peak broadening in the XRD shows the formation of nanocrystalline CdS. TEM images of CdS nanocrystallites revealed the nearly spherical shape morphology of the particles, whereas, TEM images of composite showed the deposition of CdS nanocrystallites on the OMWCNT. EDX measurements matches with a 1:1 stoichiometry of Cd and S in CdS nanocrystallites, whereas, that of the composite showed the presence of Cd and S along with C. The vibrational properties of CdS nanocrystallites and their composite with OMWCNT were studied by Raman spectroscopy. Furthermore, the photocatalytic activity studies for the degradation of methylene blue under visible light irradiation using these materials were carried out. The surface area calculated using BET surface analyzer for CdS-OMWCNT composite (148.31 m 2 /g) was found to be more compared to bare CdS nanocrystallites (56.78 m 2 /g). The CdS-OMWCNT composite exhibited very good photocatalytic activity for the degradation of methylene blue under visible light irradiation which has been attributed to the increased surface area and synergistic effect in the composite compared to bare CdS nanocrystallites. - Highlights: • The carbon based nanocomposite of CdS (CdS-OMWCNT) have been prepared. • Simple solvothermal decomposition method has been used. • Single-source molecular precursor in presence of carbon nanotubes has been employed. • The photocatalytic activity of CdS NPs and CdS-OMWCNT composite have been

  10. Au Nanoparticles as Interfacial Layer for CdS Quantum Dot-sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Zhu Guang

    2010-01-01

    Full Text Available Abstract Quantum dot-sensitized solar cells based on fluorine-doped tin oxide (FTO/Au/TiO2/CdS photoanode and polysulfide electrolyte are fabricated. Au nanoparticles (NPs as interfacial layer between FTO and TiO2 layer are dip-coated on FTO surface. The structure, morphology and impedance of the photoanodes and the photovoltaic performance of the cells are investigated. A power conversion efficiency of 1.62% has been obtained for FTO/Au/TiO2/CdS cell, which is about 88% higher than that for FTO/TiO2/CdS cell (0.86%. The easier transport of excited electron and the suppression of charge recombination in the photoanode due to the introduction of Au NP layer should be responsible for the performance enhancement of the cell.

  11. Enhancing Worker Health Through Clinical Decision Support (CDS): An Introduction to a Compilation.

    Science.gov (United States)

    Filios, Margaret S; Storey, Eileen; Baron, Sherry; Luensman, Genevieve B; Shiffman, Richard N

    2017-11-01

    This article outlines an approach to developing clinical decision support (CDS) for conditions related to work and health. When incorporated in electronic health records, such CDS will assist primary care providers (PCPs) care for working patients. Three groups of Subject Matter Experts (SMEs) identified relevant clinical practice guidelines, best practices, and reviewed published literature concerning work-related asthma, return-to-work, and management of diabetes at work. SMEs developed one recommendation per topic that could be supported by electronic CDS. Reviews with PCPs, staff, and health information system implementers in five primary care settings confirmed that the approach was important and operationally sound. This compendium is intended to stimulate a dialogue between occupational health specialists and PCPs that will enhance the use of work information about patients in the primary care setting.

  12. Shape and phase control of CdS nanocrystals using cationic surfactant in noninjection synthesis

    Directory of Open Access Journals (Sweden)

    Zou Yu

    2011-01-01

    Full Text Available Abstract Monodispersed CdS nanocrystals with controllable shape and phase have been successfully synthesized in this study by adding cationic surfactant in noninjection synthesis system. With the increase of the amount of cetyltrimethylammonium chloride (CTAC added, the shape of the CdS nanocrystals changed from spherical to multi-armed, and the phase changed from zinc-blende to wurtzite. It was found that halide ion Cl- plays a key role in the transformation, and other halide ions such as Br- can also induce similar transformation. We proposed that the strong binding between Cd2+ and halide ions reduced the reactivity of the precursors, decreased the nuclei formed in the nucleation stage, and led to the high concentration of precursor in the growth stage, resulting in the increase of size and phase transformation of CdS nanocrystals. In addition, it was found that the multi-armed CdS nanocrystals lost quantum confinement effect because of the increase of the size with the increase of the concentration of CTAC.

  13. Chemical Bath Deposition and Characterization of CdS layer for CZTS Thin Film Solar Cell

    OpenAIRE

    Kamal, Tasnim; Parvez, Sheikh; Matin, Rummana; Bashar, Mohammad Shahriar; Hossain, Tasnia; Sarwar, Hasan; Rashid, Mohammad Junaebur

    2016-01-01

    CZTS is a new type of an absorber and abundant materials for thin film solar cells (TFSC). Cadmium sulfide (CdS) is the n-type buffer layer of it with band gap of 2.42 eV. Cadmium sulfide (CdS) buffer layer of CZTS solar cell was deposited on soda-lime glass substrates by the Chemical Bath Deposition(CBD) method, using anhydrous Cadmium chloride(CdCl_2) and Thiourea (CS(NH_2)_2). Deposition of CdS using CBD is based on the slow release of Cd^ ions and S^ ions in an alkaline bath which is achi...

  14. A comparative study of thermal annealing effects under various atmospheres on nano-structured CdS thin films prepared by CBD

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Lingjun; Li, Jianmin; Chen, Guilin; Zhu, Changfei, E-mail: cfzhu@ustc.edu.cn; Liu, Weifeng, E-mail: liuwf@ustc.edu.cn

    2013-10-05

    Highlights: •Smooth and uniform CdS thin films were deposited successfully by CBD method. •The influence of CdCl{sub 2}-assisted annealing under various atmospheres of CdS films has been investigated. •We gave a more detailed research on annealing temperature after identified the most optimal annealing method. •High quality CdS films were obtained with air–CdCl{sub 2}-assisted treatments at 400 °C for 0.5 h. •GIXRD was used as a new analysis method of CdS in this paper. -- Abstract: Cadmium sulfide (CdS) nanofilms have been deposited on the glass substrate using the chemical bath technique. The effects of CdCl{sub 2}-assisted annealing under different atmosphere (vacuum, Ar and air) on the structural, morphological and optical properties of CdS nanofilms have been studied. After identifying the optimal annealing atmosphere, we also investigated the CdS thin film annealed at different annealing temperature (300, 400 and 500 °C). Films have been characterized by GI-XRD analysis, scanning electron microscopy, and UV–Vis–NIR spectrophotometer. The as-deposited CdS films have been found to be nanocrystalline in nature with a mixture of two crystallographic phases: a hexagonal phase and a cubic phase. After annealed in air with a CdCl{sub 2} coating layer at 400 °C, the films showed pure hexagonal phase, indicating the phase transition of CdS. It was found that the treatment in air with a CdCl{sub 2} coating layer increased the crystallinity and the mean grain size of CdS film, which are advantageous to the application in solar cells as a window layer material.

  15. In situ generated CdS nanostructure induced enhanced photoluminescence from Dy{sup 3+} ions doped dielectric nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Chirantan; Karmakar, Basudeb [Glass Science and Technology Section, Glass Division, CSIR-Central Glass and Ceramic Research Institute, Kolkata (India)

    2017-08-15

    We report CdS nanostructure induced enhanced photoluminescence (PL) from Dy{sup +3}:CdS co-doped dielectric-nanocomposites synthesized by the conventional melt-quench technique. CdS nanocrystals (NCs) were synthesized as in situ within the dielectric medium and their growth was controlled by heat treatment duration. Nanoparticles were investigated with absorption spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and Raman spectroscopy. The experimentally obtained sizes of the NCs are found to increase from 5-11 nm to 50-80 nm. Bandgap enhancement for the carrier confinement was found to alter within the range of 0.20-0.38 eV. Phonon confinement effect has been confirmed by blue shifting of Raman peak for CdS NCs at 303 cm{sup -1}. Enhanced highly intense sharp PL peak at 576 nm was detected, and different parameters associated with the PL enhancement including energy transfer from CdS NCs to Dy{sup 3+} ions have been studied. This PL enhancement was steered by varying CdS NC sizes. Enhanced PL of these nanocomposites finds their potential applications as gain medium in the field of solid state lasers. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. A DFT study of the effects of Sc doping on electronic and optical properties of CdS nanoparticles

    Directory of Open Access Journals (Sweden)

    Ur Rehman Shafiq

    2015-12-01

    Full Text Available In the present work a systematic study was carried out to understand the influence of Sc doping on electronic and optical properties of CdS nanoparticles. The geometry optimization and symmetry computation for CdS and Sc doped CdS nanoparticles using Density Functional Theory (DFT on B3LYP level with the QZ4P for Cd and DZ2P for sulphur and Sc were performed by Amsterdam Density Functional (ADF. The results show that HOMO-LUMO gap as well as electronic and optical properties of CdS clusters vary with Sc doping. The HOMO-LUMO gap is affected by the dopant and its value decreases to 0.6 eV. Through considering the numerical integration scheme in the ADF package, we investigated different vibrational modes and our calculated Raman and IR spectra are consistent with the reported result. The calculated IR and Raman peaks of CdS and Sc doped CdS clusters were in the range of 100 to 289 cm−1, 60 cm−1 to 350 cm−1 and 99 cm−1 to 282 cm−1, 60 cm−1 to 350 cm−1, respectively, which was also confirmed by experiment as well as a blue shift occurrence. Subsequently, for deeper research of pure and doped CdS clusters, their absorption spectra were calculated using time-dependent DFT method.

  17. Surface dependent behaviour of CdS LO-phonon mode

    International Nuclear Information System (INIS)

    Molina-Contreras, J R; Medina-Gutierrez, C; Frausto-Reyes, C; Trejo-Vazquez, R; Villalobos-Pina, F J; Romo-Luevano, G; Calixto, S

    2007-01-01

    In this paper, we develop a sensitive optical method to monitor the surface roughness in the investigation of surfaces. By applying this method to measure the RMS surface roughness of various surfaces, we found RMS values which are comparable to those obtained by atomic force microscopy measurements. In addition, we present a simple empirical model to calculate the RMS surface roughness which shows very good agreement with the surface roughness measurements taken by the method reported in this paper. Finally, the application of our method to the study of the LO-phonon mode of CdS suggests that its intensity is dominated by the surface roughness. This roughness dependent behaviour of the CdS LO-phonon mode is experimentally confirmed by using an excitation wavelength near its E 0 transition

  18. Hydrothermal synthesis and sol-gel methods for CdS particle production in different morphologies and their use in wastewater applications

    OpenAIRE

    Tuncer, Cansel

    2018-01-01

    In this study, CdSnanoparticles were synthesized in different sizes and morphologies using twodifferent methods. First, the synthesis of both cauliflower-type CdS microspheresand CdS nanoflower-type microstructures by hydrothermal synthesis was carriedout in a steel reactors with teflon chamber. While polyethylene glycol andthioacetamide were used in the synthesis of cauliflower-type CdS microspheres,thiourea was used as a sulfur source in the synthesis of nanoflower CdS microstructures.Spher...

  19. Controllable synthesis and characterization of CdS quantum dots by a microemulsion-mediated hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Rongrong; Han, Boning; Yang, Lin, E-mail: yanglin@hbu.edu.cn; Yang, Yanmin; Xu, Ying; Mai, Yaohua, E-mail: yaohuamai@hbu.edu.cn

    2016-04-15

    CdS QDs were successfully synthesized through a chemical reaction between cadmium acetate dehydrate and thioacetamide by using a microemulsion-mediated hydrothermal method. The properties of as-prepared CdS QDs can be controlled by using Emulsifier OP and CTAB surfactant, which produce a universal cubic phase and an unusual hexagonal phase, respectively. As a comparison, CdS QDs prepared by CTAB exhibit a better crystallinity and dispersibility. A possible mechanism involving the critical role of surfactant in the formation of crystal structure has also been explored in this paper. It is also found that the crystal size gradually increase with the increase of temperature, and the observation of red-shift in the absorption and emission peaks gives a clear evidence of the quantum confinement effect. All the desired properties of CdS QDs synthesized in this study imply the possibility of the preparation of high quality QDs under the appropriate reaction conditions.

  20. Synthesis of CdS nanocrystals in polymeric films studied by in-situ GID and GISAXS

    KAUST Repository

    Di Luccio, Tiziana; Carbone, Dina; Masala, Silvia; Ramachandran, Karthik; Kornfield, Julie

    2015-01-01

    In this work, we describe the synthesis of CdS nanocrystals in thin polymeric films by in-situ Grazing Incidence Diffraction (GID) and Grazing Incidence Small Angle Scattering (GISAXS). The 2D GISAXS patterns indicate how the precursor structure is altered as the temperature is varied from 25°C to 300°C. At 150°C, the CdS nanocrystals start to arrange themselves in a hexagonal lattice with a lattice parameter of 27 A. The diffraction intensity from the hexagonal lattice reaches a maximum at 170"C and decreases steadily upon further heating above 220°C indicating loss of symmetry. Correspondingly, the GID scans at 170°C show strong crystalline peaks from cubic CdS nanocrystals that are about 2 nm size. The results indicate that a temperature of 170°C is sufficient to synthesize CdS nanocrystals without degradation of the polymer matrix (Topas) in thin films (about 30nm). © 2015 Materials Research Society.

  1. Surface-modified CdS nanoparticles as a fluorescent probe for the selective detection of cysteine

    International Nuclear Information System (INIS)

    Negi, Devendra P S; Chanu, T Inakhunbi

    2008-01-01

    We present a novel method for the selective detection of cysteine, a sulfur-containing amino acid, which plays a crucial role in many important biological functions such as protein folding. Surface-modified colloidal CdS nanoparticles have been used as a fluorescent probe to selectively detect cysteine in the presence of other amino acids in the micromolar concentration range. Cysteine quenches the emission of CdS in the 0.5-10 μM concentration range, whereas the other amino acids do not affect its emission. Among the other amino acids, histidine is most efficient in quenching the emission of the CdS nanoparticles. The sulfur atom of cysteine plays a crucial role in the quenching process in the 0.5-10 μM concentration range. Cysteine is believed to quench the emission of the CdS nanoparticles by binding to their surface via its negatively charged sulfur atom. This method can potentially be applied for its detection in biological samples.

  2. Synthesis of CdS nanocrystals in polymeric films studied by in-situ GID and GISAXS

    KAUST Repository

    Di Luccio, Tiziana

    2015-07-07

    In this work, we describe the synthesis of CdS nanocrystals in thin polymeric films by in-situ Grazing Incidence Diffraction (GID) and Grazing Incidence Small Angle Scattering (GISAXS). The 2D GISAXS patterns indicate how the precursor structure is altered as the temperature is varied from 25°C to 300°C. At 150°C, the CdS nanocrystals start to arrange themselves in a hexagonal lattice with a lattice parameter of 27 A. The diffraction intensity from the hexagonal lattice reaches a maximum at 170"C and decreases steadily upon further heating above 220°C indicating loss of symmetry. Correspondingly, the GID scans at 170°C show strong crystalline peaks from cubic CdS nanocrystals that are about 2 nm size. The results indicate that a temperature of 170°C is sufficient to synthesize CdS nanocrystals without degradation of the polymer matrix (Topas) in thin films (about 30nm). © 2015 Materials Research Society.

  3. Synthesis of CdS flower-like hierarchical microspheres as electrode material for electrochemical performance

    International Nuclear Information System (INIS)

    Kaviyarasu, K.; Manikandan, E.; Maaza, M.

    2015-01-01

    We report in this paper, a facile hydrothermal route for the preparation of CdS nanocrystals at room temperature (RT). Composition, structure and morphology of the products were analyzed and characterized by X-ray diffraction (XRD) confirms that the hydrothermal treatment at 180 °C for periods ranging from 0 to 1440 min caused no significant modification of the long range order structure subjected to hydrothermal treatment. From the XRD analysis the diffraction peaks pertaining to 26.75°, 43.89° and 52.34° are attributed to the (111), (220) and (311) planes of cubic zinc blende structure. The Photoluminescence (PL) spectra are dominated by a strong narrow band edge emission tunable in the blue region of the visible spectra indicating the narrow size distribution of CdS nanocrystals. TEM observation shows that the CdS nanocrystals synthesized by hydrothermal synthesis are well dispersed and the average crystallite size was found to be ∼10 nm. The confocal microscopic studies reveal that each flower like spheres is due to Ostwald's ripening with numerous nanoparticles aggregating a surface. - Highlights: • The adjacent particle coalesces together forming spherical particles. • The average crystalline size of CdS nanoparticles was found to be ∼3 nm. • In the case of spherical crystallite, is given by L = 3/4 D. • The CdS nanocrystal exhibits a direct band gap of 2.4 eV. • The microspheres are dispersed with good monodispersity

  4. Growth kinetics and long-term stability of CdS nanoparticles in aqueous solution under ambient conditions

    International Nuclear Information System (INIS)

    Mullaugh, Katherine M.; Luther, George W.

    2011-01-01

    The ubiquity of naturally occurring nanoparticles in the aquatic environment is now widely accepted, but a better understanding of the conditions that promote their formation and persistence is needed. Using cadmium sulfide (CdS) as a model metal sulfide species, thiolate-capped CdS nanoparticles were prepared in the laboratory to evaluate how aquatic conditions influence metal sulfide nanoparticle growth and stability. This work examines CdS nanoparticle growth directly in aqueous solution at room temperature by utilizing the size-dependent spectroscopic properties of semiconductors detectable by UV/vis. CdS nanoparticle growth was governed by oriented attachment, a non-classical mechanism of crystallization in which small precursor nanoparticles coalesce to form larger nanoparticle products. Nanoparticle growth was slowed with increasing capping agent and decreasing ionic strength. In addition to examining the short-term (hours) growth of the nanoparticles, a long-term study was conducted in which cysteine-capped CdS nanoparticles were monitored over 3 weeks in solutions of various ionic strengths. The long-term study revealed an apparent shift from small nanoparticles to nanoparticles twice their original size, suggesting nanoparticle growth may continue through oriented attachment over longer time scales. High-ionic strength solutions resulted in salt-induced aggregation and eventual settling of nanoparticles within days, whereas low-ionic strength solutions were stable against settling over the course of the experiment. Sulfide recovery from cysteine-capped CdS nanoparticles as acid volatile sulfide was nearly quantitative after 2 weeks in fully oxygenated water, demonstrating significantly slowed oxidation of sulfide when complexed to Cd(II) within CdS nanoparticles. The nanoparticles were also shown to be resistant to oxidation by Fe(III) (hydr)oxide. This study illustrates that aggregation, rather than chemical oxidation, is likely more important to the

  5. In-situ boron doping of chemical-bath deposited CdS thin films

    International Nuclear Information System (INIS)

    Khallaf, Hani; Park, S.; Schulte, Alfons; Chai, Guangyu; Lupan, Oleg; Chow, Lee; Heinrich, Helge

    2009-01-01

    In-situ boron doping of CdS using chemical-bath deposition (CBD) is reported. The effect of B doping on optical properties, as well as electrical properties, crystal structure, chemistry, and morphology of CdS films is studied. We present a successful approach towards B doping of CdS using CBD, where a resistivity as low as 1.7 x 10 -2 Ωcm and a carrier density as high as 1.91 x 10 19 cm -3 were achieved. The bandgap of B-doped films was found to slightly decrease as the[B]/[Cd] ratio in the solution increases. X-ray diffraction studies showed B 3+ ions likely enter the lattice substitutionally. A phase transition, due to annealing, as well as induced lattice defects, due to B doping, were detected by micro-Raman spectroscopy and transmission electron microscopy. The chemistry and morphology of films were unaffected by B doping. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Electrophoretic deposition of CdS coatings and their photocatalytic activities in the degradation of tetracycline antibiotic

    Energy Technology Data Exchange (ETDEWEB)

    Vázquez, A., E-mail: alejandro.lqi@gmail.com [Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Av. Universidad S/N, San Nicolás de los Garza, 66455 Nuevo León (Mexico); Hernández-Uresti, D.B., E-mail: ing.dianahdz@gmail.com [Universidad Autónoma de Nuevo León, CICFIM–Facultad de Ciencias Físico Matemáticas, Av. Universidad S/N, San Nicolás de los Garza, 66455 Nuevo León (Mexico); Obregón, S. [Universidad Autónoma de Nuevo León, CICFIM–Facultad de Ciencias Físico Matemáticas, Av. Universidad S/N, San Nicolás de los Garza, 66455 Nuevo León (Mexico)

    2016-11-15

    Highlights: • CdS photocatalyst was prepared by electrophoretic deposition. • The CdS coating was used in the photodegradation of antibiotics. • O{sub 2}{sup −} and ·OH radicals were responsible for the degradation of tetracycline. - Abstract: The photocatalytic activities of CdS coatings formed by electrophoretic deposition (EPD) were evaluated through the photodegradation of an antibiotic, tetracycline. First, CdS nanoparticles were synthesized under microwave irradiation of aqueous solutions containing the cadmium and sulfur precursors at stoichiometric amounts and by using trisodium citrate as stabilizer. Microwave irradiation was carried out in a conventional microwave oven at 2.45 GHz and 1650 W of nominal power, for 60 s. The CdS nanoparticles were characterized by UV–vis spectrophotometry, photoluminescence and X-ray diffraction. Electrophoretic deposition parameters were 300 mV, 600 mV and 900 mV of applied voltage between aluminum plates separated by 1 cm. The fractal dimensions of the surfaces were evaluated by atomic force microscopy and correlated to the morphological and topographic characteristics of the coatings. The photocatalytic activity of the CdS coatings was investigated by means the photodegradation of the tetracycline antibiotic under simulated sunlight irradiation. According to the results, the photoactivity of the coatings directly depends on the concentration of the precursors and the applied voltage during the deposition. The material obtained at 600 mV showed the best photocatalytic behavior, probably due to its physical properties, such as optimum load and suitable aggregate size.

  7. Turning “on” and “off” nucleation and growth: Microwave assisted synthesis of CdS clusters and nanoparticles

    International Nuclear Information System (INIS)

    Ferrer, Edmy; Nater, Sariann; Rivera, Daniel; Colon, Jean Marie; Zayas, Francisco; Gonzalez, Miguel; Castro, Miguel E.

    2012-01-01

    Graphical abstract: Display Omitted Highlights: ► Cadmium acetate and DMSO were employed as ion precursors. ► New approach to controlled CdS nanoparticle synthesis. ► CdS clusters and nanoparticles synthesis achieved using microwave irradiation. ► Microwave irradiation turns on and off nanoparticle growth. ► The formation of clusters, embryos and nanoparticles studied with optical spectroscopy. -- Abstract: We report here on the formation of CdS NP from the microwave assisted reaction of Cd(CH 3 CO 2 ) 2 with dimethylsulfoxide (DMSO). DMSO serves as the solvent and a controlled source of sulfide ions to form (CdS) 1≤n≤5 clusters at the early stages of the process. The clusters grow into CdS nanoparticles, with diameters that range from 1.6 nm up to over 250 nm, with microwave heating. The time dependence of the onset of light absorption and absorbance are consistent with a concurrent nucleation and growth processes. The formation of clusters and nuclei and their subsequent reactions is controlled by turning on and off the energy supply consistent with an energy barrier to the formation of CdS nanostructures.

  8. The Financial Management System: A Pivotal Tool for Fiscal Viability. CDS Spotlight. ECAR Research Bulletin

    Science.gov (United States)

    Lang, Leah; Pirani, Judith A.

    2014-01-01

    This spotlight focuses on data from the 2013 CDS to better understand how higher education institutions approach financial management systems. Information provided for this spotlight was derived from Module 8 of Core Data Service (CDS), which asked several questions regarding information systems and applications. Responses from 525 institutions…

  9. Structural and optical properties of Ni-doped CdS thin films prepared by chemical bath deposition method

    Energy Technology Data Exchange (ETDEWEB)

    Premarani, R. [Arumugam Pillai SeethaiAmmal College, Thiruppattur-630211 (India); Saravanakumar, S., E-mail: sarophy84@gmail.com; Chandramohan, R. [SreeSevuganAnnamalai College, Devakottai-630303 (India); Mahalingam, T. [Department of Electrical and Computer Engineering, Ajou University, Suwon 443-749 (Korea, Republic of)

    2015-06-24

    The structural and optical behavior of undoped Cadmiun Sulphide (CdS) and Ni-doped CdS thinfilms prepared by Chemical Bath Deposition (CBD) technique is reported. The crystallite sizes of the thinfilms have been characterized by X-ray diffraction pattern (XRD). The particle sizes increase with the increase of Ni content in the CdS thinfilms. Scanning Electron Microscope (SEM) results indicated that CdS thinfilms is made up of aggregate of spherical-like particles. The composition was estimated by Energy Dispersive Analysis of X-ray (EDX) and reported. Spectroscopic studies revealed considerable improvement in transmission and the band gap of the films changes with addition of Ni dopant that is associated with variation in crystallite sizes in the nano regime.

  10. Evolution of different morphologies of CdS nanoparticles by thermal decomposition of bis(thiourea)cadmium chloride in various solvents

    International Nuclear Information System (INIS)

    Gaur, Rama; Jeevanandam, P.

    2015-01-01

    CdS nanoparticles with different morphologies have been synthesized by thermal decomposition of bis(thiourea)cadmium chloride in different solvents without the use of any ligand/surfactant. CdS nanoparticles with pyramid, sponge-like and hexagonal disc-like morphologies were obtained in diphenyl ether (DPE), 1-octadecene (ODE) and ethylene glycol (EG), respectively. In addition, CdS nanoparticles with unique morphologies were obtained when the decomposition of the complex was carried out in mixed solvents (DPE–EG and ODE–EG). Extensive characterization of the CdS nanoparticles was carried out using powder X-ray diffraction, FT-IR spectroscopy, thermal analysis, field-emission scanning electron microscopy, diffuse reflectance spectroscopy and photoluminescence spectroscopy, and detailed mechanism of the formation of CdS nanoparticles with different morphologies in various solvents has been proposed

  11. Cytotoxicity and cellular mechanisms involved in the toxicity of CdS quantum dots in hemocytes and gill cells of the mussel Mytilus galloprovincialis

    Energy Technology Data Exchange (ETDEWEB)

    Katsumiti, A. [CBET Research Group, Dept. Zoology and Animal Cell Biology, Faculty of Science and Technology and Research Centre for Experimental Marine Biology and Biotechnology PIE, University of the Basque Country UPV/EHU, Basque Country (Spain); Gilliland, D. [EU Commission–Joint Research Centre, Institute of Health and Consumer Protection, NSB Unit, Ispra (Italy); Arostegui, I. [Department of Applied Mathematics, Statistics and Operations Research, Faculty of Science and Technology, University of the Basque Country UPV/EHU, Leioa (Spain); Cajaraville, M.P., E-mail: mirenp.cajaraville@ehu.es [CBET Research Group, Dept. Zoology and Animal Cell Biology, Faculty of Science and Technology and Research Centre for Experimental Marine Biology and Biotechnology PIE, University of the Basque Country UPV/EHU, Basque Country (Spain)

    2014-08-15

    Highlights: • CdS QDs were cytotoxic for mussel hemocytes and gill cells in vitro. • Ionic Cd was the most toxic form, followed by CdS QDs and bulk CdS. • CdS QDs altered oxidative balance and caused DNA damage in mussel cells. • CdS QDs caused a particle-specific immunostimulation on phagocytosis of hemocytes. • Conceptual models for cellular handling and toxicity of CdS QDs are proposed. - Abstract: CdS quantum dots (QDs) show a great promise for treatment and diagnosis of cancer and for targeted drug delivery, due to their size-tunable fluorescence and ease of functionalization for tissue targeting. In spite of their advantages it is important to determine if CdS QDs can exert toxicity on biological systems. In the present work, cytotoxicity of CdS QDs (5 nm) at a wide range of concentrations (0.001–100 mg Cd/L) was screened using neutral red (NR) and thiazolyl blue tetrazolium bromide (MTT) assays in isolated hemocytes and gill cells of mussels (Mytilus galloprovincialis). The mechanisms of action of CdS QDs were assessed at sublethal concentrations (0.31–5 mg Cd/L) in the same cell types through a series of functional in vitro assays: production of reactive oxygen species (ROS), catalase (CAT) activity, DNA damage, lysosomal acid phosphatase (AcP) activity, multixenobiotic resistance (MXR) transport activity, Na-K-ATPase activity (only in gill cells) and phagocytic activity and damage to actin cytoskeleton (only in hemocytes). Exposures to CdS QDs lasted for 24 h and were performed in parallel with exposures to bulk CdS and ionic Cd. Ionic Cd was the most toxic form to both cell types, followed by CdS QDs and bulk CdS. ROS production, DNA damage, AcP activity and MXR transport were significantly increased in both cell types exposed to the 3 forms of Cd. CAT activity increased in hemocytes exposed to the three forms of Cd while in gill cells only in those exposed to ionic Cd. No effects were found on hemocytes cytoskeleton integrity. Effects on

  12. Influence of Ag doping concentration on structural and optical properties of CdS thin film

    International Nuclear Information System (INIS)

    Kumar, Pragati; Saxena, Nupur; Gupta, Vinay; Agarwal, Avinash

    2015-01-01

    This work shows the influence of Ag concentration on structural properties of pulsed laser deposited nanocrystalline CdS thin film. X-ray photoelectron spectroscopy (XPS) studies confirm the dopant concentration in CdS films and atomic concentration of elements. XPS studies show that the samples are slightly sulfur deficient. GAXRD scan reveals the structural phase transformation from cubic to hexagonal phase of CdS without appearance of any phase of CdO, Ag 2 O or Ag 2 S suggesting the substitutional doping of Ag ions. Photoluminescence studies illustrate that emission intensity increases with increase in dopant concentration upto 5% and then decreases for higher dopant concentration

  13. Influence of Ag doping concentration on structural and optical properties of CdS thin film

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Pragati, E-mail: pkumar.phy@gmail.com [Department of Physics, Bareilly College, Bareilly, 243 005, Uttar Pradesh (India); Department of Physics and Astrophysics, University of Delhi, Delhi, 110 007 (India); Saxena, Nupur; Gupta, Vinay [Department of Physics and Astrophysics, University of Delhi, Delhi, 110 007 (India); Agarwal, Avinash [Department of Physics, Bareilly College, Bareilly, 243 005, Uttar Pradesh (India)

    2015-05-15

    This work shows the influence of Ag concentration on structural properties of pulsed laser deposited nanocrystalline CdS thin film. X-ray photoelectron spectroscopy (XPS) studies confirm the dopant concentration in CdS films and atomic concentration of elements. XPS studies show that the samples are slightly sulfur deficient. GAXRD scan reveals the structural phase transformation from cubic to hexagonal phase of CdS without appearance of any phase of CdO, Ag{sub 2}O or Ag{sub 2}S suggesting the substitutional doping of Ag ions. Photoluminescence studies illustrate that emission intensity increases with increase in dopant concentration upto 5% and then decreases for higher dopant concentration.

  14. Study of electrostatically self-assembled thin films of CdS and ZnS nanoparticle semiconductors

    Science.gov (United States)

    Suryajaya

    In this work, CdS and ZnS semiconducting colloid nanoparticles coated with organic shell, containing either SO[3-] or NH[2+] groups, were deposited as thin films using the technique of electrostatic self-assembly. The films produced were characterized with UV-vis spectroscopy and spectroscopic ellipsometry - for optical properties; atomic force microscopy (AFM) - for morphology study; mercury probe - for electrical characterisation; and photon counter - for electroluminescence study. UV-vis spectra show a substantial blue shift of the main absorption band of both CdS and ZnS, either in the form of solutions or films, with respect to the bulk materials. The calculation of nanoparticles' radii yields the value of about 1.8 nm for both CdS and ZnS.The fitting of standard ellipsometry data gave the thicknesses (d) of nanoparticle layers of around 5 nm for both CdS and ZnS which corresponds well to the size of particles evaluated from UV-vis spectral data if an additional thickness of the organic shell is taken into account. The values of refractive index (n) and extinction coefficient (k) obtained were about 2.28 and 0.7 at 633 nm wavelength, for both CdS and ZnS.Using total internal reflection (TIRE), the process of alternative deposition of poly-allylamine hydrochloride (PAH) and CdS (or ZnS) layers could be monitored in-situ. The dynamic scan shows that the adsorption kinetic of the first layer of PAH or nanoparticles was slower than that of the next layer. The fitting of TIRE spectra gavethicknesses of about 7 nm and 12 nm for CdS and ZnS, respectively. It supports the suggestion of the formation of three-dimensional aggregates of semiconductor nanoparticles intercalated with polyelectrolyte.AFM images show the formation of large aggregates of nanoparticles, about 40-50 nm, for the films deposited from original colloid solutions, while smaller aggregates, about 12-20 nm, were obtained if the colloid solutions were diluted.Current-voltage (I-V) and capacitance

  15. Decrease of back recombination rate in CdS quantum dots sensitized solar cells using reduced graphene oxide

    International Nuclear Information System (INIS)

    Badawi Ali

    2015-01-01

    The photovoltaic performance of CdS quantum dots sensitized solar cells (QDSSCs) using the 0.2 wt% of reduced graphene oxide and TiO 2 nanoparticles (RGO+TiO 2 nanocomposite) photoanode is investigated. CdS QDs are adsorbed onto RGO+TiO 2 nanocomposite films by the successive ionic layer adsorption and reaction (SILAR) technique for several cycles. The current density–voltage (J–V) characteristic curves of the assembled QDSSCs are measured at AM1.5 simulated sunlight. The optimal photovoltaic performance for CdS QDSSC was achieved for six SILAR cycles. Solar cells based on the RGO+TiO 2 nanocomposite photoanode achieve a 33% increase in conversion efficiency (η) compared with those based on plain TiO 2 nanoparticle (NP) photoanodes. The electron back recombination rates decrease significantly for CdS QDSSCs based on RGO+TiO 2 nanocomposite photoanodes. The lifetime constant (τ) for CdS QDSSC based on the RGO+TiO 2 nanocomposite photoanode is at least one order of magnitude larger than that based on the bare TiO 2 NPs photoanode. (paper)

  16. Self-Assembly of TiO2/CdS Mesoporous Microspheres with Enhanced Photocatalytic Activity via Hydrothermal Method

    Directory of Open Access Journals (Sweden)

    Sujing Yu

    2014-01-01

    Full Text Available Self assembly of TiO2/CdS mesoporous microspheres was synthesized via hydrothermal method. The samples were characterized by X-ray powder diffraction (XRD, ultraviolet-visible diffuse reflectance spectroscopy (DRS, transmission electron microscopy (TEM, energy-dispersive spectroscopy analysis (EDS, high-resolution transmission electron microscopy (HRTEM, Brunauer-Emmett-Teller (BET, X-ray photoelectron spectroscopy (XPS, and photoluminescence spectra (PL. The as-synthesized TiO2/CdS mesoporous microspheres showed superior photocatalytic activity for the degradation of RhB under either visible light or simulated sunlight irradiation; the 10 wt% TiO2/CdS sample showed the best performance. Moreover, this catalyst showed improved stability, and the activity did not decrease significantly after four recycles. The heterojunction between TiO2 and CdS may be favorable for the transport of photoinduced electrons from CdS to TiO2. In addition, the mesoporous structure could increase the utilization of light energy and facilitate the diffusion of reactants and products during the photocatalytic reaction.

  17. Controllable architecture of CdS and CuS by single-source precursor-mediated approach and their photocatalytic activity

    International Nuclear Information System (INIS)

    Sahoo, Ashish K.; Srivastava, Suneel K.

    2013-01-01

    The present work deals with the preparation of hexagonal CdS and CuS by solvothermal decomposition of the morpholine-4-carbdithioate (MCDT) complexes of Cd and Cu in a water/THF mixture at 140–180 °C for 24 h and characterization. Scanning electron microscopy, field emission scanning electron microscopy and high resolution transmission electron microscopy show that CdS exhibits a hierarchical star- and lotus flower-like morphology in the presence of disodium salt of ethylenediamine tetraaceticacid and sodium dodecyl benzene sulphonate as soft templates at 140 and 160 °C, respectively. However, Cu complex of MCDT forms CuS nanoparticles in the temperature range of 140–180 °C. On the contrary, CdS nanoparticles and CuS microparticles are formed in the absence of any template under the identical experimental conditions. Raman studies show the characteristic peak of CdS and CuS, irrespective of their size and morphology. Finally, CdS and CuS of varying morphology have successfully been used as catalysts in UV photocatalytic decomposition of methylene blue dye. These findings show that CdS lotus-like microflowers are more effective catalysts than hierarchical stars, though the latter is found to have better reusability.Graphical AbstractA simple soft template-assisted and single complex source precursor-mediated solvothermal synthesis of CdS and CuS with a diverse set of morphology has been reported. In addition, the morphology and application in photocatalysis are also discussed.

  18. Controllable architecture of CdS and CuS by single-source precursor-mediated approach and their photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, Ashish K.; Srivastava, Suneel K., E-mail: sunil111954@yahoo.co.uk [Indian Institute of Technology Kharagpur, Department of Chemistry (India)

    2013-04-15

    The present work deals with the preparation of hexagonal CdS and CuS by solvothermal decomposition of the morpholine-4-carbdithioate (MCDT) complexes of Cd and Cu in a water/THF mixture at 140-180 Degree-Sign C for 24 h and characterization. Scanning electron microscopy, field emission scanning electron microscopy and high resolution transmission electron microscopy show that CdS exhibits a hierarchical star- and lotus flower-like morphology in the presence of disodium salt of ethylenediamine tetraaceticacid and sodium dodecyl benzene sulphonate as soft templates at 140 and 160 Degree-Sign C, respectively. However, Cu complex of MCDT forms CuS nanoparticles in the temperature range of 140-180 Degree-Sign C. On the contrary, CdS nanoparticles and CuS microparticles are formed in the absence of any template under the identical experimental conditions. Raman studies show the characteristic peak of CdS and CuS, irrespective of their size and morphology. Finally, CdS and CuS of varying morphology have successfully been used as catalysts in UV photocatalytic decomposition of methylene blue dye. These findings show that CdS lotus-like microflowers are more effective catalysts than hierarchical stars, though the latter is found to have better reusability.Graphical AbstractA simple soft template-assisted and single complex source precursor-mediated solvothermal synthesis of CdS and CuS with a diverse set of morphology has been reported. In addition, the morphology and application in photocatalysis are also discussed.

  19. Synthesis and characterization of TiO{sub 2}/CdS core-shell nanorod arrays and their photoelectrochemical property

    Energy Technology Data Exchange (ETDEWEB)

    Cao Chunlan [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Department of Power Engineer, Chongqing Communication College, Chongqing 400035 (China); Hu Chenguo, E-mail: hucg@cqu.edu.cn [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Shen Weidong [Department of Power Engineer, Chongqing Communication College, Chongqing 400035 (China); Wang, Shuxia [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Tian Yongshu [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Department of Power Engineer, Chongqing Communication College, Chongqing 400035 (China); Wang Xue [Department of Applied Physics, Chongqing University, Chongqing 400044 (China)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer TiO{sub 2}/CdS core-shell nanorod arrays were fabricated by spin-SILAR method. Black-Right-Pointing-Pointer The enhanced photocurrent was found in the TiO{sub 2}/CdS core-shell nanorod arrays. Black-Right-Pointing-Pointer The CdS coated on TiO{sub 2} increases the e-h separation and enlarges light absorption range. - Abstract: TiO{sub 2}/CdS core-shell nanorod arrays have been fabricated via a two-step method. Vertically aligned TiO{sub 2} nanorod arrays (NRs) were synthesized by a facile hydrothermal method, and followed by depositing CdS nanoparticles on TiO{sub 2} NRs by spin-coating successive ion layer adsorption and reaction (spin-SILAR) method. The surface morphology, structure, optical and photoelectrochemical behaviors of the core-shell NRs films are considered. The UV-vis absorption spectrum results suggested that the absorption peak of the TiO{sub 2}/CdS core-shell NRs shifts from the ultraviolet region to the visible region in comparison to that of the pure TiO{sub 2} NRs. The obviously enhanced photoelectrochemical (PEC) performances of the heterojunction NRs were found under illumination of the simulated sunlight in comparison with that of the TiO{sub 2} NRs. The enhanced PEC performance and formation mechanism of TiO{sub 2}/CdS core-shell NRs were discussed in detail.

  20. Fluorescence Quenching of Dendrimer-Encapsulated CdS Quantum Dots for the Detection of H{sub 2}O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Hyojung; Kim, Hai Dong; Kim, Joohoon [Kyung Hee Un iversity, Seoul (Korea, Republic of)

    2016-02-15

    Hydrogen peroxide (H{sub 2}O{sub 2}) exists in natural environments as a byproduct of various enzymatic and photochemical reactions. Various approaches have been reported for the synthesis of cadmium sulfide (CdS) QDs using dendrimers, which can be categorized mainly into two general approaches. The first approach utilizes dendrimers as capping agents, resulting in the formation of agglomerates of spatially segregated QDs stabilized by multiple dendrimers. We have described the synthesis and characterization of the CdS QDs using G6-NH{sub 2} dendrimers. By controlling the molar ratios (n = Cd2+/G6-NH{sub 2}) between the Cd{sup 2+} ions and G6-NH{sub 2} dendrimers, we synthesized a set of CdS QDs with different structural and optical properties. Importantly, the synthesized CdS QDs exhibited H{sub 2}O{sub 2}-sensitive fluorescence, which can be utilized for the detection of H{sub 2}O{sub 2}. Especially, the CdS QDs with n = 64 displayed a Stern–Volmer relationship between the fluorescence of the CdS QDs and the concentration of H{sub 2}O{sub 2}, as well as the strongest fluorescence among the set of the synthesized CdS QDs. Since core-shell structures of QDs often result in enhanced stability and quantum efficiency of the QDs, we are currently working on core-shell structured QDs prepared using dendrimers to improve their stability and quantum yield compared to the CdS QDs reported in the present study.

  1. Synthesis and spectral studies on Cd(II) dithiocarbamate complexes and their use as precursors for CdS nanoparticles

    Science.gov (United States)

    Sathiyaraj, Ethiraj; Padmavathy, Krishnaraj; Kumar, Chandran Udhaya; Krishnan, Kannan Gokula; Ramalingan, Chennan

    2017-11-01

    Bis(N-cyclopropyl-N-4-chlorobenzyldithiocarbamato-S,S‧)cadmium(II) (1) and (2,2‧-bipyridine) bis(N-cyclopropyl-N-4-chlorobenzyldithiocarbamato-S,S‧)cadmium(II) (2) have been synthesized and characterized by FT-IR, 1HNMR and 13C NMR analyses. For the complex 2, single crystal X-ray diffraction analysis and computational studies (optimized geometry, HOMO-LUMO and MEP) have been executed employing DFT/B3LYP method with LANL 2DZ basic set. The optimized bond lengths and bond angles agree well with the experimental results. The complexes 1 and 2 have been used as single source precursors for the synthesis of ethyleneglycol capped CdS1 and CdS2 nanoparticles, respectively. CdS1 and CdS2 nanoparticles have been synthesized by solvothermal method. PXRD, SEM, Elemental colour mapping, EDAX, TEM and UV-Vis spectroscopy have been used to characterize the as-prepared CdS nanoparticles. The X-ray diffraction pattern confirms both their hexagonal structures.

  2. Influence of hydrogen peroxide on the stability and optical properties of CdS quantum dots in gelatin

    Energy Technology Data Exchange (ETDEWEB)

    Klyuev, V.G.; Volykhin, D.V., E-mail: volykhin.d@ya.ru; Ivanova, A.A.

    2017-03-15

    Influence of hydrogen peroxide on the stability and optical characteristics of CdS quantum dots obtained by aqueous synthesis in gelatin is investigated. It is shown that the action of hydrogen peroxide on the CdS quantum dots reduces the average particle size, increases monodispersity of particle size distribution, and also increases the photoluminescence intensity. A model that explains the behavior of CdS quantum dots photoluminescence with a decrease of particle size as a result of treatment with hydrogen peroxide is presented.

  3. Photoacoustic Study of CdS QDs for Application in Quantum-Dot-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    S. Abdallah

    2012-01-01

    Full Text Available The optical properties and photovoltaic characterization of CdS quantum dots sensitized solar cells (QDSSCs were studied. CdS QDs were prepared by the chemical solution deposition (CD technique. Photoacoustic spectroscopy (PA was employed to study the optical properties of the prepared samples. The sizes of the CdS QDs were estimated from transmission electron microscope (TEM micrographs gives radii ranged from 1.57 to 1.92 nm. The current density-voltage (J-V characteristic curves of the assembled QDSSCs were measured. Fluorine doped Tin Oxide (FTO substrates were coated with 20 nm-diameter TiO2 nanoparticles (NPs. Presynthesized colloidal CdS quantum dots of different particles size were deposited on the TiO2-coated substrates using direct adsorption (DA method. The FTO counter electrodes were coated with platinum, while the electroelectrolyte containing I-/I-3 redox species was sandwiched between the two electrodes. The short current density (Jsc and efficiency (η increases as the particle size increases. The values of Jsc increases linearly with increasing the intensities of the sun light which indicates the greater sensitivity of the assembled cells.

  4. Spectral properties of ultrasmall CdS nanoparticles Stabilized by mercaptoacids and hydrazine

    International Nuclear Information System (INIS)

    Solonenko, Dmytro I.; Rayevska, Oleksandra Ye.; Stroyuk, Oleksandr L.; Kuchmiy, Stepan Ya.

    2013-01-01

    Ultrasmall colloidal CdS quantum dots (QDs) were synthesized in water at room temperature by using a combination of two low-molecular-weight stabilizers - hydrazine and a mercaptoacid, particularly, mercaptoacetic and mercaptopropionic-2 acids. The average size of QDs was found to depend on the Cd-to-S ratio at the synthesis and be as small as 2,5 nm at 80% cadmium(II) excess. The CdS QDs emit broadband photoluminescence in the visible spectrum range with a relative quantum yield of around 5% and the radiative life time of around 100 ns. (authors)

  5. CdS nanoparticles/CeO_2 nanorods composite with high-efficiency visible-light-driven photocatalytic activity

    International Nuclear Information System (INIS)

    You, Daotong; Pan, Bao; Jiang, Fan; Zhou, Yangen; Su, Wenyue

    2016-01-01

    Graphical abstract: Coupling CdS with CeO_2 can effectively improve the light-harvesting ability of wide-band gap CeO_2 NRs as the photoinduced electrons on the conduction band of CdS are transfered to the conduction band of CeO_2. - Highlights: • Coupling CdS can effectively improve the light-harvesting ability of wide-band gap CeO_2. • CdS/CeO_2 composites show high photocatalytic activity under visible light irradiation. • The mechanism of photocatalytic H_2 evolution over CdS/CeO_2 was proposed. - Abstract: Different mole ratios of CdS nanoparticles (NPs)/CeO_2 nanorods (NRs) composites with effective contacts were synthesized through a two-step hydrothermal method. The crystal phase, microstructure, optical absorption properties, electrochemical properties and photocatalytic H_2 production activity of these composites were investigated. It was concluded that the photogenerated charge carriers in the CdS NPs/CeO_2 NRs composite with a proper mole ratio (1:1) exhibited the longest lifetime and highest separation efficiency, which was responsible for the highest H_2-production rate of 8.4 mmol h"−"1 g"−"1 under visible-light irradiation (λ > 420 nm). The superior photocatalytic H_2 evolution properties are attributed to the transfer of visible-excited electrons of CdS NPs to CeO_2 NRs, which can effectively extend the light absorption range of wide-band gap CeO_2 NRs. This work provides feasible routes to develop visible-light responsive CeO_2-based nanomaterial for efficient solar utilization.

  6. In vitro and in vivo assessment of nanotoxicity of CdS quantum dot/aminopolysaccharide bionanoconjugates.

    Science.gov (United States)

    de Carvalho, S M; Mansur, A A P; Mansur, H S; Guedes, M I M C; Lobato, Z I P; Leite, M F

    2017-02-01

    The nanotoxicity of Cd-containing quantum dots (QDs) for biomedical applications is very controversial and not completely understood. In this study, we evaluated the cytotoxicity of surface-biofunctionalized CdS QDs with chitosan directly synthesized via aqueous route at room temperature. These core-shell CdS-chitosan nanoconjugates showed different degrees of cytotoxic responses using MTT cell proliferation assay toward three human cell cultures, human osteosarcoma cell line (SAOS), non-Hodgkin's B cell lymphoma (Toledo), and human embryonic kidney cell line (HEK293T), under three exposure times (1, 3, and 5days) and three colloidal concentrations (10nM, 50nM, and 100nM). The results clearly demonstrated that the CdS QDs, regardless to the fact that they were coated with a biocompatible aminopolysaccharide shell, induced a severe dose- and time-dependent inhibition of cell viability. In addition, the HEK293T and SAOS cell lines showed much more sensitive response compared to Toledo, which indicated that the cytotoxicity was also cell-type dependent. The exceptional resistance of Toledo cells to toxic effects of CdS nanoconjugates even at severe test conditions was assigned to specific role of B-lineage cells of the immune defense system. Remarkably, no conclusive evidence of toxicity of CdS nanoconjugates was observed in vivo using intravenous injections of CdS nanoconjugates in BALB/c mouse animal models for 30days, but localized fluorescence was detected in ex-vivo liver tissue samples. Therefore, these results prove that there is no guarantee of "risk-free" use of CdS nanoconjugates for in vivo applications, even when functionalized with biopolymer ligands, as they can pose an excessive threat due to unpredicted and uncorrelated responses under in vitro and in vivo biological assays with highly toxic cadmium ions. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Synthesis of single crystalline CdS nanowires with polyethylene glycol 400 as inducing template

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Solvothermal technique, an one-step soft solution-processing route was successfully employed to synthesize single crystalline CdS nanowires in ethylenediamine medium at lower temperature (170 □) for 1-8 d. In this route, polyethylene glycol 400 (PEG400)was used as surfactant, which played a crucial role in preferentially oriented growth of semiconductor nanowires. Characterizations of as-prepared CdS nanowires by X-ray powder diffraction(XRD), transmission electron microscopy(TEM) indicate that the naonowires,with typical diameters of 20nm and lengths up to several micrometers, have preferential [001] orientation. Also, investigations into the physical properties of the CdS nanowires were conducted with UV-Vis absorption spectroscopy and photoluminescence emission spectroscopy. The excitonic photo-optical phenomena of the nanowires shows the potential in the practical applications.

  8. Fabrication of CdS films with superhydrophobicity by the microwave assisted chemical bath deposition.

    Science.gov (United States)

    Liu, Y; Tan, T; Wang, B; Zhai, R; Song, X; Li, E; Wang, H; Yan, H

    2008-04-15

    A simple method of microwave assisted chemical bath deposition (MA-CBD) was adopted to fabricate cadmium sulfide (CdS) thin films. The superhydrophobic surface with a water contact angle (CA) of 151 degrees was obtained. Via a scanning electron microscopy (SEM) observation, the film was proved having a porous micro/nano-binary structure which can change the property of the surface and highly enhance the hydrophobicity of the film. A possible mechanism was suggested to describe the growth of the porous structure, in which the microwave heating takes an important role in the formation of two distinct characteristic dimensions of CdS precipitates, the growth of CdS sheets in micro-scale and sphere particles in nano-scale. The superhydrophobic films may provide novel platforms for photovoltaic, sensor, microfluidic and other device applications.

  9. Open Photoacoustic Cell Configuration Applied to the Thermal Characterization of Liquid CdS Nanocomposites

    Science.gov (United States)

    Faraji, Nastaran; Mahmood Mat Yunus, W.; Kharazmi, Alireza; Saion, Elias; Behzad, Kasra

    2014-01-01

    CdS nanofluids were prepared by the gamma-radiation method at different radiation doses. The samples were characterized by UV-Vis spectroscopy and transmission electron microscopy. The open cell photoacoustic technique was used to measure the thermal effusivity of the CdS nanocomposites. In this technique a He-Ne laser was used as the excitation source and was operated at 632.8 nm with an output power of 70 mW. The precision and accuracy of this technique were initially established by measuring the thermal effusivity of distilled water and ethylene glycol. The thermal-effusivity values of these two samples were found to be close to the values reported in the literature. The thermal effusivity of CdS nanofluids decreased from (0.453 to 0.268) with increased dosage of gamma radiation.

  10. Extraction of CdS pigment from waste polyethylene

    NARCIS (Netherlands)

    Wanrooij, P.H.P.; Agarwal, U.S.; Meuldijk, J.; Kasteren, van J.M.N.; Lemstra, P.J.

    2006-01-01

    Cadmium sulfide has often been used as a pigment in plastics such as high-density polyethylene (HDPE). Removal of CdS after the useful life of plastics is desired since it poses an environmental hazard in the waste phase of these plastics. In this study, a process is investigated to convert the

  11. Structural, optical and magnetic properties of Mn diffusion-doped CdS thin films prepared by vacuum evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Aksu, S. [SoloPower, Inc., 5981 Optical Ct., San Jose, CA 95138 (United States); Bacaksiz, E., E-mail: eminb@ktu.edu.tr [Department of Physics, Karadeniz Technical University, 61080 Trabzon (Turkey); Parlak, M. [Department of Physics, Middle East Technical University, 06531 Ankara (Turkey); Yilmaz, S.; Polat, I.; Altunbas, M. [Department of Physics, Karadeniz Technical University, 61080 Trabzon (Turkey); Tuerksoy, M.; Topkaya, R. [Department of Physics, Gebze Institute of Technology, Gebze, 41400 Kocaeli (Turkey); Ozdogan, K. [Department of Physics, Yildiz Technical University, 34210 Istanbul (Turkey)

    2011-10-17

    Highlights: {yields} Cadmium sulphide thin films were deposited by vacuum evaporation. {yields} Elemental Mn was deposited onto CdS thin films by using electron beam evaporation and annealed under vacuum at different temperatures. {yields} Structural, optical and magnetic studies of Mn-doped CdS have been investigated. {yields} X-ray diffraction results showed that the undoped CdS film had a zinc-blende structure with a strong preferred orientation along the (1 1 1) direction. {yields} Magnetic measurements show that Mn-doped CdS thin films exhibit a ferromagnetism behavior at room temperature. - Abstract: The effect of Mn-doping on the vacuum deposited CdS thin films has been investigated by studying the changes in the structural, optical and magnetic properties of the films. A thin Mn layer evaporated on the CdS film surface served as the source layer for the diffusion doping. Doping was accomplished by annealing the CdS/Mn stack layers at the temperature range from 300 deg. C to 400 deg. C in step of 50 deg. C for 30 min under vacuum. The X-ray diffraction results showed that the undoped CdS film had a zinc-blende structure with a strong preferred orientation along the (1 1 1) direction. The incorporation of Mn did not cause any change in the texture but reduced the peak intensity and lead to a smaller crystallite size. Investigation of surface morphology using atomic force microscopy confirmed the decrease in the grain size with the Mn diffusion. In addition, a more uniform grain size distribution was observed in the doped films. X-ray photoelectron spectroscopy analysis showed that Mn atoms on the surface of the films were bounded to either sulphur or oxygen atoms. Auger electron spectroscopy of the diffusion-doped CdS sample at 350 deg. C indicated that the atomic Mn concentration was higher close to the surface region and Mn was distributed with a steadily decreasing profile through the bulk of the film with an average atomic concentration value around few

  12. Photoelectrochemical and Raman characterization of In2O3 mesoporous films sensitized by CdS nanoparticles

    Directory of Open Access Journals (Sweden)

    Mikalai V. Malashchonak

    2013-04-01

    Full Text Available The method of successive ion layer adsorption and reaction was applied for the deposition of CdS nanoparticles onto a mesoporous In2O3 substrate. The filling of the nanopores in In2O3 films with CdS particles mainly occurs during the first 30 cycles of the SILAR deposition. The surface modification of In2O3 with CdS nanoparticles leads to the spectral sensitization of photoelectrochemical processes that manifests itself in a red shift of the long-wavelength edge in the photocurrent spectrum by 100–150 nm. Quantum-confinement effects lead to an increase of the bandgap from 2.49 to 2.68 eV when decreasing the number of SILAR cycles from 30 to 10. The spectral shift and the widening of the Raman line belonging to CdS evidences the lattice stress on the CdS/In2O3 interfaces and confirms the formation of a close contact between the nanoparticles.

  13. News from the Library: Share your work, submit your thesis to CDS!

    CERN Multimedia

    CERN Library

    2011-01-01

    Are you a student paid by CERN, using CERN equipment or advised by CERN staff and you are currently writing a thesis? Then you should know that you are welcome to submit your final work to the CERN Document Server (CDS), where it will be made available by Open Access.   This is the most efficient way of sharing your work within the community - your thesis will certainly find a much greater audience than if you follow the advice of certain dubious publishing companies (see the article Free access to science... but at what cost? published in this issue). At the same time, you ensure long-term storage of your file. All theses qualify, from bachelor to PhD, and any language is accepted. You simply go to CDS and submit your work. If your thesis was written some years ago it is still not too late to submit it; it will then get a new life on CDS! More information here. CERN Theses collection here. If you have any questions or submission problems, please do not hesitate to contact Catherine Cart. ...

  14. Synthesis of CdS nanowire networks and their optical and electrical properties

    International Nuclear Information System (INIS)

    Ma, R M; Wei, X L; Dai, L; Huo, H B; Qin, G G

    2007-01-01

    High quality single-crystal CdS nanowire (NW) networks have been synthesized on Si(111) substrates via the chemical vapour deposition method. X-ray diffraction and selected area electron diffraction show that the NWs in the networks grow along the directions and their (0001) crystal planes are parallel to the Si(111) substrates. Room-temperature photoluminescence (PL) spectra of single CdS NWs in the networks are dominated by a near-band-edge emission and free from deep-level defect emissions. The PLs resulting from free-exciton and bound-exciton recombinations are detected at 77 K. The results of the electrical transport measurement on the CdS NW networks show that the current can flow through different NWs via the cross-junctions. The resistivity, electron concentration and electron mobility of single NWs in the networks are estimated by fitting the I-V curves measured on single NWs with the metal-semiconductor-metal model suggested by Zhang et al (2006 Appl. Phys. Lett. 88 073102; 2007 Adv. Funct. Mater. at press)

  15. Monte Carlo simulation of fast electrons and heavy particles in the CDS of nitrogen dc glow discharge

    International Nuclear Information System (INIS)

    Yu, W.; Zhang, L.Z.; Wang, J.L.; Han, L.; Fu, G.S.

    2001-01-01

    The characteristics of fast electrons (e - ) and heavy particles (N 2 + , N + , N 2f , N f ) in the cathode dark space (CDS) of nitrogen dc glow discharge are simultaneously studied by Monte Carlo simulation. The calculated energy and angular distributions of these particles at different positions from the cathode provide a clear picture of their transport behaviours within the CDS. The density and mean energy of these particles indicate that the electrons and the atomic ions (N + ) are the main high-energy species and the molecular ions (N 2 + ) are the major ions in the CDS. It can be seen from the energy distributions of the bombarding particles at the cathode surface that the molecular ions and the fast atoms (N f ) are the main active species participating in the cathode nitride material synthesis process. The influence of the backscattering of the electrons from the negative glow to the CDS is also investigated. All the calculated results provide good information on the spatial characteristics of the particles considered in this paper and also their internal connections in the CDS of nitrogen dc glow discharge. (author)

  16. Dielectric properties of CdS nanoparticles synthesized by soft ...

    Indian Academy of Sciences (India)

    If the field applied to the condenser is time-dependent (as in an alternating current), so ... tematically the dielectric properties of CdS synthesized by a soft chemical method .... The real parts of conductivity spectra can be explained by the power ...

  17. Eco-friendly intracellular biosynthesis of CdS quantum dots without changing Escherichia coli's antibiotic resistance.

    Science.gov (United States)

    Yan, Zheng-Yu; Du, Qing-Qing; Qian, Jing; Wan, Dong-Yu; Wu, Sheng-Mei

    2017-01-01

    In the paper, a green and efficient biosynthetical technique was reported for preparing cadmium sulfide (CdS) quantum dots, in which Escherichia coli (E. coli) was chosen as a biomatrix. Fluorescence emission spectra and fluorescent microscopic photographs revealed that as-produced CdS quantum dots had an optimum fluorescence emission peak located at 470nm and emitted a blue-green fluorescence under ultraviolet excitation. After extracted from bacterial cells and located the nanocrystals' foci in vivo, the CdS quantum dots showed a uniform size distribution by transmission electron microscope. Through the systematical investigation of the biosynthetic conditions, including culture medium replacement, input time point of cadmium source, working concentrations of raw inorganic ions, and co-cultured time spans of bacteria and metal ions in the bio-manufacture, the results revealed that CdS quantum dots with the strongest fluorescence emission were successfully prepared when E. coli cells were in stationary phase, with the replacement of culture medium and following the incubation with 1.0×10 -3 mol/L cadmium source for 2 days. Results of antimicrobial susceptibility testing indicated that the sensitivities to eight types of antibiotics of E. coli were barely changed before and after CdS quantum dots were prepared in the mild temperature environment, though a slight fall of antibiotic resistance could be observed, suggesting hinted the proposed technique of producing quantum dots is a promising environmentally low-risk protocol. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Optical transitions and nature of Stokes shift in spherical CdS quantum dots

    OpenAIRE

    Demchenko, D. O.; Wang, Lin-Wang

    2006-01-01

    We study the structure of the energy spectra along with the character of the states participating in optical transitions in colloidal CdS quantum dots (QDs) using the {\\sl ab initio} accuracy charge patching method combined with the %pseudopotential based folded spectrum calculations of electronic structure of thousand-atom nanostructures. In particular, attention is paid to the nature of the large resonant Stokes shift observed in CdS quantum dots. We find that the top of the valence band st...

  19. Photoelectrochemical and Raman characterization of nanocrystalline CdS grown on ZnO by successive ionic layer adsorption and reaction method

    Energy Technology Data Exchange (ETDEWEB)

    Kozytskiy, A.V. [L.V. Pysarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine, 31 Nauky Av., 03028 Kyiv (Ukraine); Stroyuk, O.L., E-mail: stroyuk@inphyschem-nas.kiev.ua [L.V. Pysarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine, 31 Nauky Av., 03028 Kyiv (Ukraine); Kuchmiy, S.Ya. [L.V. Pysarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine, 31 Nauky Av., 03028 Kyiv (Ukraine); Mazanik, A.V.; Poznyak, S.K. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Streltsov, E.A., E-mail: streltea@bsu.by [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Kulak, A.I., E-mail: kulak@igic.bas-net.by [Institute of General and Inorganic Chemistry, National Academy of Sciences of Belarus, Surganova str., 9/1, Minsk 220072 (Belarus); Korolik, O.V. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Dzhagan, V.M., E-mail: dzhagan@isp.kiev.ua [V.E. Lashkaryov Institute of Semiconductor Physics of National Academy of Sciences of Ukraine, 41 Nauky Av., 03028 Kyiv (Ukraine)

    2014-07-01

    Properties of CdS nanoparticles (NPs) grown by successive ionic layer adsorption and reaction (SILAR) method on the surface of electrodeposited ZnO films were studied by Raman, photocurrent and UV–Vis absorption spectroscopies. The CdS nanoparticles deposited at a SILAR cycle number (N) from 5 to 10 exhibit a broadening of the band gap (E{sub g}) by 0.17–0.31 eV as compared with that of the CdS particles grown at N = 30. The size quantization of the interband transition energy in CdS nanoparticles is in accordance with the Raman spectroscopic data demonstrating a considerable increase in the LO peak intensity with increasing the N from 5 to 10 as a result of transition to resonant light scattering. The spectral width of the LO peak decreases from 50 to 15 cm{sup −1} as the N increases from 5 to 30 reflecting a less pronounced effect of the nanoparticle surface on the phonon scattering. A large spectral width of the Raman peaks is assumed to originate from a complex structure of the CdS nanoparticles comprising crystallinity domains that can affect the phonon confinement. The photocurrent spectroscopy of ZnO/CdS heterostructures showed that the band gap of CdS NPs deposited at N > 20 is smaller by ∼ 0.08 eV than that of bulk cadmium sulfide. It was concluded that this effect is not associated with photoexcitation of structural defects but rather reflects intrinsic electronic properties of SILAR-deposited CdS nanoparticles. - Highlights: • Visible-light-sensitive ZnO/CdS heterostructures were prepared by SILAR. • A large Raman peak width originates from a complex structure of CdS nanoparticles. • Vibrational properties of CdS nanoparticles depend on SILAR cycle number.

  20. Photoelectrochemical and Raman characterization of nanocrystalline CdS grown on ZnO by successive ionic layer adsorption and reaction method

    International Nuclear Information System (INIS)

    Kozytskiy, A.V.; Stroyuk, O.L.; Kuchmiy, S.Ya.; Mazanik, A.V.; Poznyak, S.K.; Streltsov, E.A.; Kulak, A.I.; Korolik, O.V.; Dzhagan, V.M.

    2014-01-01

    Properties of CdS nanoparticles (NPs) grown by successive ionic layer adsorption and reaction (SILAR) method on the surface of electrodeposited ZnO films were studied by Raman, photocurrent and UV–Vis absorption spectroscopies. The CdS nanoparticles deposited at a SILAR cycle number (N) from 5 to 10 exhibit a broadening of the band gap (E g ) by 0.17–0.31 eV as compared with that of the CdS particles grown at N = 30. The size quantization of the interband transition energy in CdS nanoparticles is in accordance with the Raman spectroscopic data demonstrating a considerable increase in the LO peak intensity with increasing the N from 5 to 10 as a result of transition to resonant light scattering. The spectral width of the LO peak decreases from 50 to 15 cm −1 as the N increases from 5 to 30 reflecting a less pronounced effect of the nanoparticle surface on the phonon scattering. A large spectral width of the Raman peaks is assumed to originate from a complex structure of the CdS nanoparticles comprising crystallinity domains that can affect the phonon confinement. The photocurrent spectroscopy of ZnO/CdS heterostructures showed that the band gap of CdS NPs deposited at N > 20 is smaller by ∼ 0.08 eV than that of bulk cadmium sulfide. It was concluded that this effect is not associated with photoexcitation of structural defects but rather reflects intrinsic electronic properties of SILAR-deposited CdS nanoparticles. - Highlights: • Visible-light-sensitive ZnO/CdS heterostructures were prepared by SILAR. • A large Raman peak width originates from a complex structure of CdS nanoparticles. • Vibrational properties of CdS nanoparticles depend on SILAR cycle number

  1. Structural and Spectroscopic Studies of Sm3+/CdS Nanocrystallites in Sol-Gel TiO2-ZrO2 Matrix

    Science.gov (United States)

    Karthika, S.; Prathibha, Vasudevan; Ann, Mary K. A.; Viji, Vidyadharan; Biju, P. R.; Unnikrishnan, N. V.

    2014-02-01

    A sol-gel method was used to prepare titania-zirconia matrices doped with Sm3+/CdS nanocrystallites. The structural properties of the matrices were characterized using transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA), and Fourier-transform infrared spectroscopy studies. The thermal stability of the material was determined by TGA/DTA analysis. The absorption spectrum shows the characteristic peaks of the Sm3+ ions and the absorption peak corresponding to the CdS nanocrystallites. The optical bandgap and size of the CdS nanoparticles were calculated from the absorption spectrum. From TEM, the interplanar distance ( d) was estimated to be 3.533 Å, which matches with the (1 0 0) plane of bulk CdS. The measurements yield a nanocrystallite size of around 7.8 nm. The optical absorption and emission spectra confirmed the formation of CdS nanoparticles along with samarium ions in the titania-zirconia matrices. The fluorescence intensity of the samarium ions was found to be greatly enhanced by codoping with CdS nanocrystallites.

  2. Responsiveness of the Care Dependency Scale for Rehabilitation (CDS-R).

    Science.gov (United States)

    Eichhorn-Kissel, Juliane; Dassen, Theo; Lohrmann, Christa

    2012-03-01

    Around 10% of Western Europe's population suffer from a disability which can entail a decrease of independency and quality of life. However, the lives of these people can be improved by rehabilitative treatment and care. Changing the degree of dependency from dependent to independent is essential in rehabilitation, as is the assessment of these changes. To perform such kind of measurements, assessment instruments have to be responsive. In spite of this concern, responsiveness of assessment instruments is studied to a small extent only. This also applies to the Care Dependency Scale for Rehabilitation (CDS-R), a short assessment instrument measuring the care dependency of patients regarding physical and psychosocial aspects. In this longitudinal-study, the responsiveness of the CDS-R, in general and related to different disease-groups, should be determined. Therefore, a convenience sample of 1564 patients was assessed in an Austrian rehabilitation centre with the scale after admission and before discharge. Responsiveness was determined by descriptive analysis, calculation of effect-sizes and significance tests. Differences between admission and discharge occurred on a statistically significant level for patients who changed. Kazis' effect-sizes can be considered as of small/medium effect for patients who changed (0.24/0.49), and as of large effect according to Liang (0.86/1.46). Eta squared was 0.10/0.19 which can be interpreted as of moderate/large effect for patients who changed. Responsiveness-analyses related to different disease-groups showed constantly large effect-sizes for patients with musculoskeletal-disorders. These results indicate that the CDS-R can detect patient-changes over time and discriminate between patients who change under rehabilitation or not. These aspects argue for the responsiveness of the scale, wherefore the CDS-R seems to be appropriate for the assessment of treatment/health-care effectiveness and the evaluation of individual patient

  3. Biotemplated preparation of CdS nanoparticles/bacterial cellulose hybrid nanofibers for photocatalysis application

    International Nuclear Information System (INIS)

    Yang, Jiazhi; Yu, Junwei; Fan, Jun; Sun, Dongping; Tang, Weihua; Yang, Xuejie

    2011-01-01

    In this work, we describe a novel facile and effective strategy to prepare micrometer-long hybrid nanofibers by deposition of CdS nanoparticles onto the substrate of hydrated bacterial cellulose nanofibers (BCF). Hexagonal phase CdS nanocrystals were achieved via a simple hydrothermal reaction between CdCl 2 and thiourea at relatively low temperature. The prepared pristine BCF and the CdS/BCF hybrid nanofibers were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results reveal that the CdS nanoparticles were homogeneously deposited on the BCF surface and stabilized via coordination effect. The CdS/BCF hybrid nanofibers demonstrated high-efficiency photocatalysis with 82% methyl orange (MO) degradation after 90 min irradiation and good recyclability. The results indicate that the CdS/BCF hybrid nanofibers are promising candidate as robust visible light responsive photocatalysts.

  4. Biotemplated preparation of CdS nanoparticles/bacterial cellulose hybrid nanofibers for photocatalysis application.

    Science.gov (United States)

    Yang, Jiazhi; Yu, Junwei; Fan, Jun; Sun, Dongping; Tang, Weihua; Yang, Xuejie

    2011-05-15

    In this work, we describe a novel facile and effective strategy to prepare micrometer-long hybrid nanofibers by deposition of CdS nanoparticles onto the substrate of hydrated bacterial cellulose nanofibers (BCF). Hexagonal phase CdS nanocrystals were achieved via a simple hydrothermal reaction between CdCl(2) and thiourea at relatively low temperature. The prepared pristine BCF and the CdS/BCF hybrid nanofibers were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results reveal that the CdS nanoparticles were homogeneously deposited on the BCF surface and stabilized via coordination effect. The CdS/BCF hybrid nanofibers demonstrated high-efficiency photocatalysis with 82% methyl orange (MO) degradation after 90 min irradiation and good recyclability. The results indicate that the CdS/BCF hybrid nanofibers are promising candidate as robust visible light responsive photocatalysts. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Shift in optical properties of Mn doped CdS (A DFT+U study)

    Science.gov (United States)

    khan, M. Junaid Iqbal; Kanwal, Zarfishan; Nauman Usmani, M.

    2018-01-01

    Current study is based on PBE-GGA and GGA+U computational approach for calculating optical properties of Mn doped CdS. Cd atom in host CdS lattice (rocksalt structure) are substituted with Mn at various lattice positions and shift in optical properties is observed by increasing supercell size by employing PBE-GGA and Hubbard term. Optical properties vary with changing supercell size and show significant change for GGA+U. Blue shift in absorption spectrum and plots for PDOS, TDOS are in accordance with existing reported work. Moreover strong p-d hybridization is observed due to Mn and S orbital interactions and localization of d-states are scrutinized in vicinity of Fermi level or conduction band minima. GGA+U absorption curve shows redshift and a tremendous change in optical properties is observed due to different bonding. Doping Mn into CdS host lattice illustrates enhancement in Opto-electrical properties which maximizes CdS:Mn system scope in optoelectronic devices.

  6. Biotemplated preparation of CdS nanoparticles/bacterial cellulose hybrid nanofibers for photocatalysis application

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jiazhi; Yu, Junwei [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China); Fan, Jun [School of Environment, Nanjing University, Nanjing 210093 (China); Sun, Dongping [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China); Tang, Weihua [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China); Yang, Xuejie [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China)

    2011-05-15

    In this work, we describe a novel facile and effective strategy to prepare micrometer-long hybrid nanofibers by deposition of CdS nanoparticles onto the substrate of hydrated bacterial cellulose nanofibers (BCF). Hexagonal phase CdS nanocrystals were achieved via a simple hydrothermal reaction between CdCl{sub 2} and thiourea at relatively low temperature. The prepared pristine BCF and the CdS/BCF hybrid nanofibers were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results reveal that the CdS nanoparticles were homogeneously deposited on the BCF surface and stabilized via coordination effect. The CdS/BCF hybrid nanofibers demonstrated high-efficiency photocatalysis with 82% methyl orange (MO) degradation after 90 min irradiation and good recyclability. The results indicate that the CdS/BCF hybrid nanofibers are promising candidate as robust visible light responsive photocatalysts.

  7. Erythorbic acid promoted formation of CdS QDs in a tube-in-tube micro-channel reactor

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Yan; Tan, Jiawei; Wang, Jiexin; Chen, Jianfeng [State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029 (China); Sun, Baochang, E-mail: sunbc@mail.buct.edu.cn [State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029 (China); Shao, Lei, E-mail: shaol@mail.buct.edu.cn [State Key Laboratory of Organic–Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029 (China); Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029 (China)

    2014-12-15

    Erythorbic acid assistant synthesis of CdS quantum dots (QDs) was conducted by homogeneous mixing of two continuous liquids in a high-throughput microporous tube-in-tube micro-channel reactor (MTMCR) at room temperature. The effects of the micropore size of the MTMCR, liquid flow rate, mixing time and reactant concentration on the size and size distribution of CdS QDs were investigated. It was found that the size and size distribution of CdS QDs could be tuned in the MTMCR. A combination of erythorbic acid promoted formation technique with the MTMCR may be a promising pathway for controllable mass production of QDs.

  8. Co+ -ion implantation induced doping of nanocrystalline CdS thin films: structural, optical, and vibrational properties

    International Nuclear Information System (INIS)

    Chandramohan, S.; Sarangi, S.N.; Majumder, S.; Som, T.; Kanjilal, A.; Sathyamoorthy, R.

    2009-01-01

    Full text: Transition metal (Mn, Fe, Co and Ni) doped CdS nanostructures and nanocrystalline thin films have attracted much attention due to their anticipated applications in magneto-optical, non-volatile memory and future spintronics devices. Introduction of impurities in substitutional positions is highly desirable for such applications. Ion implantation is known to provide many advantages over conventional methods for efficient doping and possibility of its seamless integration with device processing steps. It is not governed by equilibrium thermodynamics and offers the advantages of high spatial selectivity and to overcome the solubility limits. In this communication, we report on modifications of structural morphological, optical, and vibrational properties of 90 keV Co + -ion implanted CdS thin films grown by thermal evaporation. Co + -ion implantation was performed in the fluence range of 0.1-3.6x10 16 ions cm -2 These fluences correspond to Co concentration in the range of 0.34-10.8 at % at the peak position of profile. Implantation was done at an elevated temperature of 573 K in order to avoid amorphization and to enhance the solubility of Co ions in the CdS lattice. Films were characterized by glancing angle X-ray diffraction (GAXRD), atomic force microscopy (AFM), optical absorption, and micro-Raman spectroscopy. Implantation does not lead to any secondary phase formation either in the form of impurity or the metallic clusters. However, implantation improves the crystalline quality of the samples and leads to supersaturation of Co ions in the CdS lattice. Thus, nanocrystalline CdS thin films can be considered as a good radiation- resistant material, which can be employed for prolonged use in solar cells for space applications. The optical band gap is found to decrease systematically with increasing ion fluence from 2.39 to 2.28 eV. Implantation leads to agglomeration of grains and a systematic increase in the surface roughness. Both GAXRD and micro

  9. REGIME SWITCHING DETERMINANTS OF SOVEREIGN CDS SPREADS: EVIDENCE FROM TURKEY

    Directory of Open Access Journals (Sweden)

    Umurcan Polat

    2017-12-01

    Full Text Available In this study, it is assessed the main determinants of sovereign CDS spreads in Turkey from January 2006 to December 2015. Before delving into the nonlinear Markov regime-switching model estimation, a conventional one-state linear model is estimated answering to what extent the sovereign credit risk is affected in between global and country-specific market variables and by credit ratings announcement changes. In broad strokes, the regime-switching analysis reveals that among domestic variables, it is the foreign exchange rate that affects the sovereign credit risk more in more volatile periods and among global variables, the indicators standing for global volatility risk premiums and international liquidity primarily influence the changes in the sovereign CDS spread in turbulent regimes whereas proxies for global risk free rate are significant more in tranquil regimes.

  10. Polarization dependent behavior of CdS around the first and second LO-phonon modes

    International Nuclear Information System (INIS)

    Frausto-Reyes, C.; Molina-Contreras, J.R.; Lopez-Alvarez, Y.F.; Medel-Ruiz, C.I.; Perez Ladron de Guevara, H.; Ortiz-Morales, M.

    2010-01-01

    The present work report studies on resonant Raman experimental line shape for CdS around the first and second LO-phonon modes. The application of our method to the study of LO-phonon modes of CdS suggests that the scattered intensity is dominated by the surface and dependent on polarization. Results showed that the Raman spectra for CdS, roughly fall into three groups: a broad line-wing with apparent maxima around 194 cm -1 in the range of 140 and 240 cm -1 which can be ascribed to overtone scattering from acoustic phonons; a band near the 1LO phonon mode which can be attributed to a combination of one-phonon scattering and peak acoustic phonon and finally, a band near the 2LO phonon mode which can be attributed to a combination of two-phonon scattering and peak acoustic phonon.

  11. Synthesis and application of luminescent single CdS quantum dot encapsulated silica nanoparticles directed for precision optical bioimaging

    Directory of Open Access Journals (Sweden)

    Veeranarayanan S

    2012-07-01

    Full Text Available Srivani Veeranarayanan, Aby Cheruvathoor Poulose, M Sheikh Mohamed, Yutaka Nagaoka, Seiki Iwai, Yuya Nakagame, Shosaku Kashiwada, Yasuhiko Yoshida, Toru Maekawa, D Sakthi KumarBio Nano Electronics Research Centre, Graduate School of Interdisciplinary New Science, Toyo University, Kawagoe, JapanAbstract: This paper presents the synthesis of aqueous cadmium sulfide (CdS quantum dots (QDs and silica-encapsulated CdS QDs by reverse microemulsion method and utilized as targeted bio-optical probes. We report the role of CdS as an efficient cell tag with fluorescence on par with previously documented cadmium telluride and cadmium selenide QDs, which have been considered to impart high levels of toxicity. In this study, the toxicity of bare QDs was efficiently quenched by encapsulating them in a biocompatible coat of silica. The toxicity profile and uptake of bare CdS QDs and silica-coated QDs, along with the CD31-labeled, silica-coated CdS QDs on human umbilical vein endothelial cells and glioma cells, were investigated. The effect of size, along with the time-dependent cellular uptake of the nanomaterials, has also been emphasized. Enhanced, high-specificity imaging toward endothelial cell lines in comparison with glioma cells was achieved with CD31 antibody-conjugated nanoparticles. The silica-coated nanomaterials exhibited excellent biocompatibility and greater photostability inside live cells, in addition to possessing an extended shelf life. In vivo biocompatibility and localization study of silica-coated CdS QDs in medaka fish embryos, following direct nanoparticle exposure for 24 hours, authenticated the nanomaterials' high potential for in vivo imaging, augmented with superior biocompatibility. As expected, CdS QD-treated embryos showed 100% mortality, whereas the silica-coated QD-treated embryos stayed viable and healthy throughout and after the experiments, devoid of any deformities. We provide highly cogent and convincing evidence for such

  12. pH dependent interaction of biofunctionalized CdS nanoparticles with nucleobases and nucleotides: A fluorimetric study

    International Nuclear Information System (INIS)

    Chatterjee, Anindita; Priyam, Amiya; Bhattacharya, Subhash C.; Saha, Abhijit

    2007-01-01

    The interaction of DNA bases and corresponding nucleotides with CdS nanoparticles (NPs), biofunctionalized by cysteine, has been investigated by absorption and fluorescence spectroscopy. Unique enhancement effect of adenine, in contrast to other nucleobases, on the luminescence of cysteine capped CdS (cys-CdS) NPs at both pH 7.5 and 10.5 was found, the extent of enhancement being much higher at pH 10.5. At the latter pH, the difference optical absorption spectra show development of new peak at 278 nm with corresponding decrease in the absorption of adenine at 260 nm, which is attributed to binding of adenine anion to the CdS surface through N7 of the purine ring. Appearance of a new band at 478 cm -1 and concomitant shift in the C 8 -N 7 vibrations to 1610 cm -1 in the FTIR spectra of cys-CdS NPs with adenine also suggest Cd-N7 binding on the particle surface. Amongst various nucleotides, ATP exhibited maximum luminescence enhancement on CdS NPs for a given change in concentration in the micro-molar range at physiological pH. A quantitative correlation between ATP concentration and PL enhancement of CdS NPs has been established, a step which in future might assist in developing new protocols for fluorescence sensing of adenine nucleotides under certain pathological conditions

  13. Comparative study of Cu(In,Ga)Se{sub 2}/CdS and Cu(In,Ga)Se{sub 2}/In{sub 2}S{sub 3} systems by surface photovoltage techniques

    Energy Technology Data Exchange (ETDEWEB)

    Dittrich, Th., E-mail: dittrich@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Gonzáles, A.; Rada, T. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Departamento de Física, Universidad del Norte, km 5 Via Pto Colombia, Barranquilla (Colombia); Rissom, T.; Zillner, E. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Sadewasser, S. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); International Iberian Nanotechnology Laboratory, Avda. Mestre José Veiga s/n, 4715-330 Braga (Portugal); Lux-Steiner, M. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany)

    2013-05-01

    Cu(In,Ga)Se{sub 2} absorbers were investigated by surface photovoltage (SPV) in the Kelvin probe and fixed capacitor arrangements before and after deposition of CdS or In{sub 2}S{sub 3} buffer layers as well as before and after deposition of ZnO window layers. Effects such as passivation of surface states, partial electron transfer from ZnO into In{sub 2}S{sub 3}, decrease of the ideality factor after deposition of ZnO and slow electron transfer through In{sub 2}S{sub 3} were demonstrated. The results show that SPV measurements open opportunities for dedicated studies of charge separation at hetero-junctions between ordered and disordered semiconductors. - Highlights: ► Surface photovoltage on chalcopyrite/buffer layer at different stages of formation ► Comparison of CdS and In{sub 2}S{sub 3} buffer layers ► Information about surface passivation, surface defects, ideality factor, transport.

  14. Noninjection Synthesis of CdS and Alloyed CdSxSe1−xNanocrystals Without Nucleation Initiators

    Directory of Open Access Journals (Sweden)

    Zou Yu

    2010-01-01

    Full Text Available Abstract CdS and alloyed CdSxSe1−x nanocrystals were prepared by a simple noninjection method without nucleation initiators. Oleic acid (OA was used to stabilize the growth of the CdS nanocrystals. The size of the CdS nanocrystals can be tuned by changing the OA/Cd molar ratios. On the basis of the successful synthesis of CdS nanocrystals, alloyed CdSxSe1−x nanocrystals can also be prepared by simply replacing certain amount of S precursor with equal amount of Se precursor, verified by TEM, XRD, EDX as well as UV–Vis absorption analysis. The optical properties of the alloyed CdSxSe1−x nanocrystals can be tuned by adjusting the S/Se feed molar ratios. This synthetic approach developed is highly reproducible and can be readily scaled up for potential industrial production.

  15. Photovoltaic and impedance characteristics of modified SILAR grown CdS quantum dot sensitized solar cell

    International Nuclear Information System (INIS)

    Fatehmulla, Amanullah; Farooq, W. A.; Aslam, M.; Atif, M.; Ali, S.M.; Al-Dhafir, A. M.; Yakuphanoglu, F.; Yahia, I.S.

    2014-01-01

    Cadmium Sulphide (CdS) quantum dots (QDs) were deposited on nanostructured TiO 2 film using a modified Successive Ionic Layer Adsorption and Reaction (SILAR) method. Nanostructured TiO 2 on FTO glass and Platinum on FTO are used as photoelectrode and Counter electrode respectively. High resolution Transmission Electron Microscopy (HRT EM) image revealed CdS QDs adsorbed on nanostructured TiO 2 . The photovoltaic characteristics and impedance spectroscopy properties of CdS quantum dot sensitized solar cell (QDSSC) were analyzed under air mass 1.5 illuminations. At the SILAR adsorption time of 2 min (10 cycles), the QDSSC measured a short circuit current density of 2 mA/cm 2 and an open circuit voltage of 0.45 V under air mass 1.5. In a widespread frequency range, the capacitance – voltage, the conductance – voltage, the series resistance - voltage measurements were carried out for the QDSSC applications. A conduct of positive to negative capacitance was observed from the measured characteristics of capacitance - voltage which is attributed to the injection of electrons from FTO electrode into TiO 2 . Key words: Nanostructured TiO 2 , CdS QDSSC, SILAR method, photovoltaic measurements, impedance characteristic

  16. Mesoporous CdS via Network of Self-Assembled Nanocrystals: Synthesis, Characterization and Enhanced Photoconducting Property.

    Science.gov (United States)

    Patra, Astam K; Banerjee, Biplab; Bhaumik, Asim

    2018-01-01

    Semiconduction nanoparticles are intensively studied due to their huge potential in optoelctronic applications. Here we report an efficient chemical route for hydrothermal synthesis of aggregated mesoporous cadmium sulfide (CdS) nanoparticles using supramolecular-assembly of ionic and water soluble sodium salicylate as the capping agent. The nanostructure, mesophase, optical property and photoconductivity of these mesoporous CdS materials have been characterized by using small and wide angle powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), N2-sorption, Raman analysis, Fourier transformed infrared (FT-IR), UV-Visible DSR spectroscopy, and photoconductivity measurement. Wide angle XRD pattern and high resolution TEM image analysis suggested that the particle size of the materials is within 10 nm and the nanoparticles are in well-crystallized cubic phase. Mesoporous CdS nanoparticles showed drastically enhanced photoelectrochemical response under visible light irradiation on entrapping a photosensitizer (dye) molecule in the interparticle spaces. Efficient synthesis strategy and the enhanced photo response in the mesoporous CdS material could facilitate the designing of other porous semiconductor oxide/sulfide and their applications in photon-to-electron conversion processes.

  17. Patterned structures of in situ size controlled CdS nanocrystals in a polymer matrix under UV irradiation

    International Nuclear Information System (INIS)

    Fragouli, D; Pompa, P P; Caputo, G; Cingolani, R; Athanassiou, A; Resta, V; Laera, A M; Tapfer, L

    2009-01-01

    A method of in situ formation of patterns of size controlled CdS nanocrystals in a polymer matrix by pulsed UV irradiation is presented. The films consist of Cd thiolate precursors with different carbon chain lengths embedded in TOPAS polymer matrices. Under UV irradiation the precursors are photolyzed, driving to the formation of CdS nanocrystals in the quantum size regime, with size and concentration defined by the number of incident UV pulses, while the host polymer remains macroscopically/microscopically unaffected. The emission of the formed nanocomposite materials strongly depends on the dimensions of the CdS nanocrystals, thus, their growth at the different phases of the irradiation is monitored using spatially resolved photoluminescence by means of a confocal microscope. X-ray diffraction measurements verified the existence of the CdS nanocrystals, and defined their crystal structure for all the studied cases. The results are reinforced by transmission electron microscopy. It is proved that the selection of the precursor determines the efficiency of the procedure, and the quality of the formed nanocrystals. Moreover it is demonstrated that there is the possibility of laser induced formation of well-defined patterns of CdS nanocrystals, opening up new perspectives in the development of nanodevices.

  18. Preparation of CdS nanoparticels with spin-coating assisted successive ionic layer reaction and their photoelectrochemical properties

    Directory of Open Access Journals (Sweden)

    Bao SUN

    2017-10-01

    Full Text Available In order to settle the problems in the traditional SILAR method for CdS deposition, such as smaller particles and being difficult to enhance the sensitive layers, an improved spin-coating assisted successive ionic layer reaction method (S-SILR substituted for the traditional SILAR method is used to deposit the CdS nanocrystals. The comparison between the improved and traditional methods is studied after depositing the CdS nanocrystals onto the ZnO nanorod arrays with the two approaches. Different analysis methods, SEM, XRD, UV-vis and the transit photocurrent measurement are conducted to characterize the morphologies and structures of the samples, as well as investigating the light absorption properties, and the photoelectric conversion performance of the electrodes. The results indicate that the CdS nanocrystals photosensitive layers could be totally coated onto the ZnO nanorod arrays more easily by the improved S-SILR method; the light absorption properties and the photoelectric conversion performance of the electrodes prepared by the improved S-SILR method are more excellent compared with those electrodes prepared by the traditional SILAR method. The improvement of the CdS deposition method has certain guiding significance in enhancing the operability of the preparation technology and the photovoltaic performance of the solar cells.

  19. Patterned structures of in situ size controlled CdS nanocrystals in a polymer matrix under UV irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fragouli, D; Pompa, P P; Caputo, G; Cingolani, R; Athanassiou, A [NNL-National Nanotechnology Laboratory, INFM, CNR, Via Arnesano, 73100 Lecce (Italy); Resta, V; Laera, A M; Tapfer, L [ENEA, Centro Ricerche Brindisi, SS7 Appia Km 706, I-72100 Brindisi (Italy)], E-mail: despina.fragouli@unile.it

    2009-04-15

    A method of in situ formation of patterns of size controlled CdS nanocrystals in a polymer matrix by pulsed UV irradiation is presented. The films consist of Cd thiolate precursors with different carbon chain lengths embedded in TOPAS polymer matrices. Under UV irradiation the precursors are photolyzed, driving to the formation of CdS nanocrystals in the quantum size regime, with size and concentration defined by the number of incident UV pulses, while the host polymer remains macroscopically/microscopically unaffected. The emission of the formed nanocomposite materials strongly depends on the dimensions of the CdS nanocrystals, thus, their growth at the different phases of the irradiation is monitored using spatially resolved photoluminescence by means of a confocal microscope. X-ray diffraction measurements verified the existence of the CdS nanocrystals, and defined their crystal structure for all the studied cases. The results are reinforced by transmission electron microscopy. It is proved that the selection of the precursor determines the efficiency of the procedure, and the quality of the formed nanocrystals. Moreover it is demonstrated that there is the possibility of laser induced formation of well-defined patterns of CdS nanocrystals, opening up new perspectives in the development of nanodevices.

  20. A direct investigation of photocharge transfer across monomolecular layer between C60 and CdS quantum dots by photoassisted conductive atomic force microscopy

    Directory of Open Access Journals (Sweden)

    Xiaohong Jiang

    2016-04-01

    Full Text Available The composite assembly of C60 and CdS Quantum Dots (QDs on ITO substrate was prepared by Langmuir-Blodgett (LB technique using arachic acid (AA, stearic acid (SA and octadecanyl amine (OA as additives. Photoassisted conductive atomic force microscopy was used to make point contact current-voltage (I-V measurements on both the CdS QDs and the composite assembly of C60/CdS. The result make it clear that the CdS, C60/CdS assemblies deposited on ITO substrate showed linear characteristics and the current increased largely under illumination comparing with that in the dark. The coherent, nonresonant tunneling mechanism was used to explain the current occurrence. It is considered that the photoinduced carriers CdS QDs tunneled through alkyl chains increased the current rapidly.

  1. Electrical transport properties of an isolated CdS microrope composed of twisted nanowires

    OpenAIRE

    Yu, Gui-Feng; Yu, Miao; Pan, Wei; Han, Wen-Peng; Yan, Xu; Zhang, Jun-Cheng; Zhang, Hong-Di; Long, Yun-Ze

    2015-01-01

    CdS is one of the important II-VI group semiconductors. In this paper, the electrical transport behavior of an individual CdS microrope composed of twisted nanowires is studied. It is found that the current?voltage (I-V) characteristics show two distinct power law regions from 360 down to 60?K. Space-charge-limited current (SCLC) theory is used to explain these temperature- and electric-field-dependent I-V curves. The I-V data can be well fitted by this theory above 100?K, and the correspondi...

  2. Improved electrical stability of CdS thin film transistors through Hydrogen-based thermal treatments

    KAUST Repository

    Salas Villaseñor, Ana L.

    2014-06-01

    Thin film transistors (TFTs) with a bottom-gate configuration were fabricated using a photolithography process with chemically bath deposited (CBD) cadmium sulfide (CdS) films as the active channel. Thermal annealing in hydrogen was used to improve electrical stability and performance of the resulting CdS TFTs. Hydrogen thermal treatments results in significant V T instability (V T shift) improvement while increasing the I on/I off ratio without degrading carrier mobility. It is demonstrated that after annealing V T shift and I on/I off improves from 10 V to 4.6 V and from 105 to 10 9, respectively. Carrier mobility remains in the order of 14.5 cm2 V s-1. The reduced V T shift and performance is attributed to a reduction in oxygen species in the CdS after hydrogen annealing, as evaluated by Fourier transform infrared spectroscopy (FTIR). © 2014 IOP Publishing Ltd.

  3. Improved electrical stability of CdS thin film transistors through Hydrogen-based thermal treatments

    KAUST Repository

    Salas Villaseñ or, Ana L.; Mejia, Israel I.; Sotelo-Lerma, Mé rida; Guo, Zaibing; Alshareef, Husam N.; Quevedo-Ló pez, Manuel Angel Quevedo

    2014-01-01

    Thin film transistors (TFTs) with a bottom-gate configuration were fabricated using a photolithography process with chemically bath deposited (CBD) cadmium sulfide (CdS) films as the active channel. Thermal annealing in hydrogen was used to improve electrical stability and performance of the resulting CdS TFTs. Hydrogen thermal treatments results in significant V T instability (V T shift) improvement while increasing the I on/I off ratio without degrading carrier mobility. It is demonstrated that after annealing V T shift and I on/I off improves from 10 V to 4.6 V and from 105 to 10 9, respectively. Carrier mobility remains in the order of 14.5 cm2 V s-1. The reduced V T shift and performance is attributed to a reduction in oxygen species in the CdS after hydrogen annealing, as evaluated by Fourier transform infrared spectroscopy (FTIR). © 2014 IOP Publishing Ltd.

  4. Polarization-resolved degenerate four-wave mixing of CdS nanocrystals in a nonresonant region

    International Nuclear Information System (INIS)

    Ma, S.M.; Seo, J.T.; Yang, Q.; Creemore, L.; Battle, R.; Tabibi, B.; Yu, W.

    2006-01-01

    The third-order susceptibilities of various concentrations of TOPO-passivated CdS nanocrystals (NCs) with the size near the Bohr radius were investigated using polarization-resolved degenerate four-wave mixing (DFWM) in a nonresonant excitation region with 532 nm wavelength and 8 ns pulse width. The second hyperpolarizabilities left angle γ h xxxx right angle and left angle γ h xyyx right angle of the CdS NCs were ∝1.25 x 10 -42 m 5 /V 2 and ∝3.66 x 10 -43 m 5 /V 2 , respectively. The ratio (left angle γ h xyyx right angle / left angle γ h xxxx right angle) of the hyperpolarizabilities was ∝0.29 that indicated a large contribution of electronic polarization process to the third-order nonlinearity of CdS NCs. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Turning “on” and “off” nucleation and growth: Microwave assisted synthesis of CdS clusters and nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Ferrer, Edmy; Nater, Sariann; Rivera, Daniel; Colon, Jean Marie; Zayas, Francisco; Gonzalez, Miguel [Chemical Imaging Center, Department of Chemistry, The University of Puerto Rico at Mayaguez, Mayaguez, PR 00680 (United States); Castro, Miguel E., E-mail: miguel.castro2@upr.edu [Chemical Imaging Center, Department of Chemistry, The University of Puerto Rico at Mayaguez, Mayaguez, PR 00680 (United States)

    2012-11-15

    Graphical abstract: Display Omitted Highlights: ► Cadmium acetate and DMSO were employed as ion precursors. ► New approach to controlled CdS nanoparticle synthesis. ► CdS clusters and nanoparticles synthesis achieved using microwave irradiation. ► Microwave irradiation turns on and off nanoparticle growth. ► The formation of clusters, embryos and nanoparticles studied with optical spectroscopy. -- Abstract: We report here on the formation of CdS NP from the microwave assisted reaction of Cd(CH{sub 3}CO{sub 2}){sub 2} with dimethylsulfoxide (DMSO). DMSO serves as the solvent and a controlled source of sulfide ions to form (CdS){sub 1≤n≤5} clusters at the early stages of the process. The clusters grow into CdS nanoparticles, with diameters that range from 1.6 nm up to over 250 nm, with microwave heating. The time dependence of the onset of light absorption and absorbance are consistent with a concurrent nucleation and growth processes. The formation of clusters and nuclei and their subsequent reactions is controlled by turning on and off the energy supply consistent with an energy barrier to the formation of CdS nanostructures.

  6. Synthesis, characterization, and applications of microheterogeneous-templated CdS nanodispersions

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Indrajyoti [Jadavpur University, Centre for Surface Science, Department of Chemistry (India); Dinda, Gargi [Jadavpur University, Department of Food Technology and Biochemical Engineering (India); Ghosh, Soumen; Moulik, Satya P., E-mail: spmcss@yahoo.com [Jadavpur University, Centre for Surface Science, Department of Chemistry (India)

    2012-08-15

    CdS nanoparticles were prepared by reacting CdCl{sub 2} and Na{sub 2}S in different microemulsions and several micellar media comprising combinations of ionic liquid, ionic, nonionic, zwitterionic amphiphiles, isopropyl alcohol, and isopropylmyristate as templates. This simple chemical method was found to be effective in the preparation of CdS dispersions mostly in the range of 3-8 nm with moderate polydispersity. The dispersions were characterized by taking UV-Vis and fluorescence spectra as well as by DLS, EDX, SEM, and TEM methods. Globular, sharp-edged elongated flake-like, and wire type morphologies were witnessed by SEM. TEM results evidenced spherical nanoentities. The dispersions witnessed both fairly and weakly semiconducting varieties; insulator-type dispersions were also observed. They have shown characteristic fluorescence properties. The nanodispersions evidenced biocidal activities toward both gram-positive and gram-negative bacteria.

  7. CDS is not what you think - Hypoarticulation in Danish Child Directed Speech

    DEFF Research Database (Denmark)

    Dideriksen, Christina Rejkjær; Fusaroli, Riccardo

    et al. 2008). A previous study relying on lab-elicited stimuli indicated that Danish CDS might be peculiar, with a surprising lack of increased articulation (Bohn 2013). In the current study, we focused on longer naturalistic recordings in an environment known and safe for both child and mother...... common CDS acoustic traits: increased pitch and pitch variability and lower speech rate. However, we also find a significantly reduced vowel space when compared to adult-directed speech, which is especially surprising given the wide range of Danish vocalic sounds. We are currently extending the analysis...... and cultural affordances and the many complex routes to learn a language....

  8. Remarkably enhanced photocatalytic hydrogen evolution over MoS2 nanosheets loaded on uniform CdS nanospheres

    Science.gov (United States)

    Chai, Bo; Xu, Mengqiu; Yan, Juntao; Ren, Zhandong

    2018-02-01

    The MoS2/CdS composites with layered MoS2 loaded on uniform CdS nanospheres were synthesized by a two-step process combination hydrothermal and solvothermal treatments, and then applied in photocatalytic hydrogen evolution under visible light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Raman spectra, UV-vis diffuse reflectance absorption spectra (UV-DRS), nitrogen adsorption-desorption measurement, photoluminescence spectra (PL) and photoelectrochemical tests. The effects of loading contents of MoS2 in the composites on the photocatalytic H2 evolution activity were comparatively investigated with 0.45 mol L-1 Na2S and 0.55 mol L-1 Na2SO3 as sacrificial agents. The results showed that the 5 wt% MoS2/CdS composite could achieve the highest photocatalytic H2 evolution rate of 372 μmol h-1 and apparent quantum efficiency (AQE) about 7.31% under 420 nm monochromatic light irradiation. The remarkably enhanced photocatalytic activity of MoS2/CdS composite could be attributed to the effective transfer and separation of photogenerated charge carriers, and MoS2 being as a cocatalyst to facilitating photocatalytic H2 evolution reaction. A tentative mechanism of MoS2/CdS composites as photocatalysts for H2 evolution was proposed.

  9. CdS nanoparticles/CeO{sub 2} nanorods composite with high-efficiency visible-light-driven photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    You, Daotong; Pan, Bao; Jiang, Fan; Zhou, Yangen; Su, Wenyue, E-mail: suweny@fzu.edu.cn

    2016-02-15

    Graphical abstract: Coupling CdS with CeO{sub 2} can effectively improve the light-harvesting ability of wide-band gap CeO{sub 2} NRs as the photoinduced electrons on the conduction band of CdS are transfered to the conduction band of CeO{sub 2}. - Highlights: • Coupling CdS can effectively improve the light-harvesting ability of wide-band gap CeO{sub 2}. • CdS/CeO{sub 2} composites show high photocatalytic activity under visible light irradiation. • The mechanism of photocatalytic H{sub 2} evolution over CdS/CeO{sub 2} was proposed. - Abstract: Different mole ratios of CdS nanoparticles (NPs)/CeO{sub 2} nanorods (NRs) composites with effective contacts were synthesized through a two-step hydrothermal method. The crystal phase, microstructure, optical absorption properties, electrochemical properties and photocatalytic H{sub 2} production activity of these composites were investigated. It was concluded that the photogenerated charge carriers in the CdS NPs/CeO{sub 2} NRs composite with a proper mole ratio (1:1) exhibited the longest lifetime and highest separation efficiency, which was responsible for the highest H{sub 2}-production rate of 8.4 mmol h{sup −1} g{sup −1} under visible-light irradiation (λ > 420 nm). The superior photocatalytic H{sub 2} evolution properties are attributed to the transfer of visible-excited electrons of CdS NPs to CeO{sub 2} NRs, which can effectively extend the light absorption range of wide-band gap CeO{sub 2} NRs. This work provides feasible routes to develop visible-light responsive CeO{sub 2}-based nanomaterial for efficient solar utilization.

  10. Enhancement of visible light photocatalytic activity of ZnS and CdS nanoparticles based on organic and inorganic coating

    Energy Technology Data Exchange (ETDEWEB)

    Soltani, Nayereh, E-mail: nayereh.soltani@gmail.com [Department of Physics, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Saion, Elias; Yunus, W. Mahmood Mat; Erfani, Maryam; Navasery, Manizheh; Bahmanrokh, Ghazaleh [Department of Physics, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Rezaee, Kadijeh [Department of Nuclear Engineering, Faculty of Advance Sciences and Technologies, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of)

    2014-01-30

    Coating of ZnS and CdS nanoparticles with organic and inorganic materials can extend their light absorption in the visible region and their stability against photo-corrosion. Such materials could emerge as excellent photocatalysts for the elimination of pollutants from aqueous media using solar energy. In this study, PVP (polyvinyl pyrrolidone)-capped ZnS and CdS nanoparticles, ZnS/CdS and CdS/ZnS core shell nanoparticles were synthesized by microwave irradiation method and characterized using different techniques. The XRD patterns exhibited cubic and hexagonal structures for coated ZnS and CdS nanoparticles, respectively. Morphological evaluation of TEM images showed that the nanoparticles are generally spherical in shape. The UV–visible spectra confirmed a shift in the band gap of coated nanoparticles to longer or shorter wavelengths due to size and potential-well effects. The photocatalytic activity of nanoparticles toward dye degradation under visible light was found to be improved after coating. PVP-capped ZnS and CdS exhibited an enhancement in the initial methylene blue degradation efficiency by a factor of about 1.3. ZnS nanoparticles coated by CdS displayed the initial efficiency 3.2 times higher than bare ZnS. The maximum dye removal was obtained in presence of CdS/ZnS core shells which is 1.4 times more efficient than bare CdS.

  11. Surfactant-ligand co-assisted solvothermal technique for the synthesis of different-shaped CdS nanorod-based materials

    International Nuclear Information System (INIS)

    Bao Chunyan; Jin Ming; Lu Ran; Xue Pengchong; Zhang Qinglin; Wang Dejun; Zhao Yingying

    2003-01-01

    1-D nanorods, twinrods, golfclubs, and tripods of CdS were prepared via a surfactant-ligand co-assisted solvothermal method at 160 deg. C. The surfactant of S-dodecylisothiounium bromide (C 12 ) used in the process was favorable for synthesis of different-shaped CdS nanorod with high aspect ratio. X-ray diffraction (XRD) and TEM images showed that the 1-D nanorods had wurtzite phase and others had a zinc blende core and wurtzite arms. The morphologies of CdS prepared under different conditions suggested the 'template-assistance' of the surfactant and that the nonaqueous organic media are important for the self-assembling of inorganic components at atomic level

  12. Brillouin scattering, piezobirefringence, and dispersion of photoelastic coefficients of CdS and ZnO

    DEFF Research Database (Denmark)

    Berkowicz, R.; Skettrup, Torben

    1975-01-01

    We have measured the dispersion of the Brillouin scattering from acoustoelectrical domains in CdS and ZnO. These spectra are compared with the birefringence spectra obtained by applying uniaxial stress. The resonant cancellation of the Brillouin scattering occurs at the spectral position of the i......We have measured the dispersion of the Brillouin scattering from acoustoelectrical domains in CdS and ZnO. These spectra are compared with the birefringence spectra obtained by applying uniaxial stress. The resonant cancellation of the Brillouin scattering occurs at the spectral position...... of the isotropic point of the stress-induced birefringence. From these spectra it is concluded that the Brillouin scattering in CdS and ZnO is determined by elasto-optic effects alone. The spectra of some of the photoelastic coefficients have been determined. A model dielectric constant is derived where both....... It is found that the exchange interaction between the excitons may change the values of the photoelastic coefficients in ZnO about 10%....

  13. A preliminary study of CdS for solar cells using combined TEM and cathodoluminescence

    International Nuclear Information System (INIS)

    Mam, K.; Durose, K.; Halliday, D.P.; Szczerbakow, A.

    2005-01-01

    A study of the suitability of a combined transmission electron microscope (TEM)/cathodoluminescence (CL) imaging and spectroscopy apparatus for investigations of CdS is presented. Photoluminescence (PL) was used to evaluate the effect of the Ar + and I + ion beam thinning used in TEM specimen preparation of CdS: a minor increase in yellow emission (594 nm) resulted. However, excitation of luminescence spectra in the TEM had a quenching effect on red luminescence (734 nm), this being considered due to the high excitation density compared to that in PL. Significant electron beam damage to the CdS could be avoided by using scanning transmission electron microscope (STEM) illumination in preference to the conventional TEM mode, which generally uses higher beam current density. Dislocation images were correlated with contrast in the STEM-CL imaging mode. The potential of the apparatus to make further direct correlations of CL images with diffraction contrast TEM imaging was assessed using the Rose visibility criterion

  14. Influence of two different template removal methods on the micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres

    Science.gov (United States)

    Wang, Han; Jin, Tingting; Zheng, Xing; Jiang, Bo; Zhu, Chaosheng; Yuan, Xiangdong; Zheng, Jingtang; Wu, Mingbo

    2016-11-01

    Hollow cadmium sulfide (CdS) nanospheres of about 260 nm average diameters and about 30 nm shell thickness can be easily synthesized via a sonochemical process, in which polystyrene (PS) nanoparticles were employed as templates. In order to remove the PS templates, both etching and calcination were applied in this paper. The influence of the two different template removal methods on the surface micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres was carefully performed a comparative study. Results of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, FT-IR, thermogravimetric analysis, Brunauer-Emmett-Teller, diffused reflectance spectra, and decolorization experiments showed that the different template removal methods exhibited a significant influence on the surface micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres. The CdS hollow nanospheres as-prepared by etching had pure cubic sphalerite structure, higher -OH content, less defects and exhibited good photocatalytic activity for rhodamine-B, Methylene Blue and methyl orange under UV-vis light irradiation. However, CdS hollow nanospheres obtained by calcination with a hexagonal crystal structure, less -OH content, more defects have shown worse photocatalytic activity. This indicated that surface micromorphology and crystalline phase were mainly factors influencing photocatalytic activity of hollow CdS nanospheres.

  15. Investigations on structural, vibrational, morphological and optical properties of CdS and CdS/Co films by ultrasonic spray pyrolysis

    International Nuclear Information System (INIS)

    Aksay, S.; Polat, M.; Ozer, T.; Koese, S.; Guerbuez, G.

    2011-01-01

    CdS and CdS/Co films have been deposited on glass substrates by an ultrasonic spray pyrolysis method. The effects of Co incorporation on the structural, optical, morphological, elemental and vibrational properties of these films were investigated. XRD analysis confirmed the hexagonal wurtzite structure of all films and had no impurity phase. While CdS film has (0 0 2) as the preferred orientation, CdS/Co films have (1 1 0) as the preferred orientation. The direct optical band gap was found to decrease from 2.42 to 2.39 eV by Co incorporation. The decrease of the direct energy gaps by increasing Co contents is mainly due to the sp-d exchange interaction between the localized d-electrons of Co 2+ ions and band electrons of CdS. After the optical investigations, it was seen that the transmittance of CdS films decreased by Co content. The Raman measurements revealed two peaks corresponding to the 1LO and 2LO modes of hexagonal CdS. The vibrational modes of Cd-S were obtained in the wavenumber range (590-715 cm -1 ) using Fourier transform infrared spectroscopy (FTIR). The elemental analysis of the film was done by energy dispersive X-ray spectrometry.

  16. Investigations on structural, vibrational, morphological and optical properties of CdS and CdS/Co films by ultrasonic spray pyrolysis

    Science.gov (United States)

    Aksay, S.; Polat, M.; Özer, T.; Köse, S.; Gürbüz, G.

    2011-09-01

    CdS and CdS/Co films have been deposited on glass substrates by an ultrasonic spray pyrolysis method. The effects of Co incorporation on the structural, optical, morphological, elemental and vibrational properties of these films were investigated. XRD analysis confirmed the hexagonal wurtzite structure of all films and had no impurity phase. While CdS film has (0 0 2) as the preferred orientation, CdS/Co films have (1 1 0) as the preferred orientation. The direct optical band gap was found to decrease from 2.42 to 2.39 eV by Co incorporation. The decrease of the direct energy gaps by increasing Co contents is mainly due to the sp-d exchange interaction between the localized d-electrons of Co2+ ions and band electrons of CdS. After the optical investigations, it was seen that the transmittance of CdS films decreased by Co content. The Raman measurements revealed two peaks corresponding to the 1LO and 2LO modes of hexagonal CdS. The vibrational modes of Cd-S were obtained in the wavenumber range (590-715 cm-1) using Fourier transform infrared spectroscopy (FTIR). The elemental analysis of the film was done by energy dispersive X-ray spectrometry.

  17. Synthesis of CdS nanorod arrays and their applications in flexible piezo-driven active H2S sensors

    International Nuclear Information System (INIS)

    Wang, Penglei; Deng, Ping; Nie, Yuxin; Zhao, Yayu; Xing, Lili; Xue, Xinyu; Zhang, Yan

    2014-01-01

    A flexible piezo-driven active H 2 S sensor has been fabricated from CdS nanorod arrays. By coupling the piezoelectric and gas sensing properties of CdS nanorods, the piezoelectric output generated by CdS nanorod arrays acts not only as a power source, but also as a response signal to H 2 S. Under externally applied compressive force, the piezoelectric output of CdS nanorod arrays is very sensitive to H 2 S. Upon exposure to 600 ppm H 2 S, the piezoelectric output of the device decreased from 0.32 V (in air) to 0.12 V. Such a flexible device can be driven by the tiny mechanical energy in our living environment, such as human finger pinching. Our research can stimulate a research trend on designing new material systems and device structures for high-performance piezo-driven active gas sensors. (paper)

  18. A direct investigation of photocharge transfer across monomolecular layer between C{sub 60} and CdS quantum dots by photoassisted conductive atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xiaohong; Liu, He; Zhang, Xingtang; Cheng, Gang; Wang, Shujie; Du, Zuliang, E-mail: zld@henu.edu.cn [Key Laboratory for Special Functional Materials, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng, 475004, PR. China (China)

    2016-04-15

    The composite assembly of C{sub 60} and CdS Quantum Dots (QDs) on ITO substrate was prepared by Langmuir-Blodgett (LB) technique using arachic acid (AA), stearic acid (SA) and octadecanyl amine (OA) as additives. Photoassisted conductive atomic force microscopy was used to make point contact current-voltage (I-V) measurements on both the CdS QDs and the composite assembly of C{sub 60}/CdS. The result make it clear that the CdS, C{sub 60}/CdS assemblies deposited on ITO substrate showed linear characteristics and the current increased largely under illumination comparing with that in the dark. The coherent, nonresonant tunneling mechanism was used to explain the current occurrence. It is considered that the photoinduced carriers CdS QDs tunneled through alkyl chains increased the current rapidly.

  19. Preparation of CdS microtrumpets from a solvent extraction system by a two-phase approach

    International Nuclear Information System (INIS)

    Geng, Aifang; Liu, Yubing; Liao, Wuping

    2011-01-01

    Highlights: → CdS microtrumpets were prepared from an extraction system by a two-phase approach. → Triethanolamine plays a crucial role in the formation of the trumpets. → Some micro-lotus seedpods can also be obtained with trihydroxymethyl aminomethane. -- Abstract: CdS microtrumpets with the length being of about 4 μm and the bell wall being of 100 nm have been prepared using a cadmium di-(2-ethylhexyl) phosphoric acid chelate as the precursor by a two-phase thermal approach. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis spectroscopy. The effects of temperature, reaction time, and co-surfactant on the morphology were also examined. It was found that the co-surfactant triethanolamine plays a crucial role in the formation of the cubic phase trumpet-like CdS microstructures.

  20. Effect of Gd{sup 3+} doping and reaction temperature on structural and optical properties of CdS nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, Gajanan, E-mail: pandeygajanan@rediffmail.com [Department of Applied Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, (U.P.) (India); Dixit, Supriya; Shrivastava, A.K. [School of Studies in Physics, Jiwaji University, Gwalior, 474011, (M.P.) (India)

    2015-10-15

    Graphical abstract: - Highlights: • Cd{sub 1−x}Gd{sub x}S nanoparticles have been prepared in aqueous medium in presence of CTAB. • From XRD, EDX and ICP-OES study, successful doping of Gd{sup 3+} in CdS has been proved. • Gd{sup 3+} doping reduced size of NCs, while temperature increased size and altered shape. • Gd{sup 3+} doping and reaction temperature influenced the optical properties of NCs. - Abstract: CdS and Gd{sup 3+} ions doped CdS nanoparticles have been prepared at two reaction temperatures 90 and 120 °C in aqueous medium in presence of cationic surfactant cetyltrimethylammonium bromide. X-ray diffraction study revealed predominant formation of zinc blend CdS and Gd:CdS at 90 °C, while at 120 °C, phase pure wurtzite CdS and Gd:CdS were formed. From EDX spectra and ICP-OES analysis, successful doping of Gd{sup 3+} ions in CdS host has been proved. Fourier transform infrared spectroscopy results show the interaction of CTAB through headgroup at the nanoparticles surface. In the transmission electron microscopy images, it has been observed that the reaction temperature and Gd{sup 3+} doping played critical role on size and shape of nanocrystals. In UV–visible absorption as well as photoluminescence emission spectra, size and shape-dependent quantum confinement effect has been observed. On Gd{sup 3+} doping, surface states related emission peak shifted to higher wavelength, while intensity of peaks increased on increasing temperature.

  1. Interfacial passivation of CdS layer to CdSe quantum dots-sensitized electrodeposited ZnO nanowire thin films

    International Nuclear Information System (INIS)

    Zhang, Jingbo; Sun, Chuanzhen; Bai, Shouli; Luo, Ruixian; Chen, Aifan; Sun, Lina; Lin, Yuan

    2013-01-01

    ZnO porous thin films with nanowire structure were deposited by the one-step electrochemical deposition method. And a CdS layer was coated on the as-deposited ZnO nanowire thin films by successive ionic layer adsorption and reaction (SILAR) method to passivate surface states. Then the films were further sensitized by CdSe quantum dots (QDs) to serve as a photoanode for fabricating quantum dots-sensitized solar cells (QDSSCs). The effect of the CdS interfacial passivation layer on the performance of the QDSSCs was systematically investigated by varying the SILAR cycle number and heating the passivation layer. The amorphous CdS layer with an optimized thickness can effectively suppress the recombination of the injected electrons with holes on QDs and the redox electrolyte. The newly formed CdS layer on the surface of the ZnO nanowire thin film obviously prolongs the electron lifetime in the passivated ZnO nanoporous thin film because of the lower surface trap density in the ZnO nanowires after CdS deposition, which is favorable to the higher short-circuit photocurrent density (J sc ). For the CdSe QDs-sensitized ZnO nanoporous thin film with the interfacial passivation layer, the J sc and conversion efficiency can reach a maximum of 8.36 mA cm −2 and 2.36%, respectively. The conversion efficiency was improved by 83.47% compared with that of the cell based on the CdSe QDs-sensitized ZnO nanoporous thin film without CdS interfacial passivation (0.39%)

  2. Synthesis of Nanocrystalline CdS by SILAR and Their Characterization

    Directory of Open Access Journals (Sweden)

    Partha Protim Chandra

    2014-01-01

    Full Text Available A simple and cost effective chemical technique has been utilized to prepare cadmium sulphide (CdS nanoparticles at room temperature. The sample is characterized with XRD (X-ray diffractometer, SEM (scanning electron microscope, TEM (transmission electron microscope, FTIR (Fourier transform infrared, EDX (energy dispersive X-rays, and UV-VIS (ultraviolet visible spectrophotometer. The particle size estimated using X-ray line broadening method is ~21.5 nm. While particle size estimation, both instrumental and strain broadening was taken into account. The lattice strain was evaluated using Williamson-Hall equation. SEM illustrates formation of submicron size crystallites and TEM image gives a particle size of ~23.5 nm. The characteristic stretching vibration frequency of CdS was observed in the absorption band in FTIR spectrum. Optical absorption study exhibits a band gap energy value of about 2.44 eV.

  3. Photovoltaic and Impedance Spectroscopy Study of Screen-Printed TiO₂ Based CdS Quantum Dot Sensitized Solar Cells.

    Science.gov (United States)

    Atif, M; Farooq, W A; Fatehmulla, Amanullah; Aslam, M; Ali, Syed Mansoor

    2015-01-19

    Cadmium sulphide (CdS) quantum dot sensitized solar cells (QDSSCs) based on screen-printed TiO₂ were assembled using a screen-printing technique. The CdS quantum dots (QDs) were grown by using the Successive Ionic Layer Adsorption and Reaction (SILAR) method. The optical properties were studied by UV-Vis absorbance spectroscopy. Photovoltaic characteristics and impedance spectroscopic measurements of CdS QDSSCs were carried out under air mass 1.5 illuminations. The experimental results of capacitance against voltage indicate a trend from positive to negative capacitance because of the injection of electrons from the Fluorine doped tin oxide (FTO) electrode into TiO₂.

  4. Growth, characterization and estimation of lattice strain and size in CdS nanoparticles: X-ray peak profile analysis

    Science.gov (United States)

    Solanki, Rekha Garg; Rajaram, Poolla; Bajpai, P. K.

    2018-05-01

    This work is based on the growth, characterization and estimation of lattice strain and crystallite size in CdS nanoparticles by X-ray peak profile analysis. The CdS nanoparticles were synthesized by a non-aqueous solvothermal method and were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman and UV-visible spectroscopy. XRD confirms that the CdS nanoparticles have the hexagonal structure. The Williamson-Hall (W-H) method was used to study the X-ray peak profile analysis. The strain-size plot (SSP) was used to study the individual contributions of crystallite size and lattice strain from the X-rays peaks. The physical parameters such as strain, stress and energy density values were calculated using various models namely, isotropic strain model, anisotropic strain model and uniform deformation energy density model. The particle size was estimated from the TEM images to be in the range of 20-40 nm. The Raman spectrum shows the characteristic optical 1LO and 2LO vibrational modes of CdS. UV-visible absorption studies show that the band gap of the CdS nanoparticles is 2.48 eV. The results show that the crystallite size estimated from Scherrer's formula, W-H plots, SSP and the particle size calculated by TEM images are approximately similar.

  5. SXPS investigation of the Cd partial electrolyte treatment of CuInSe2 absorbers

    International Nuclear Information System (INIS)

    Hunger, R.; Schulmeyer, T.; Klein, A.; Jaegermann, W.; Lebedev, M.V.; Sakurai, K.; Niki, S.

    2005-01-01

    The chemical modification of polycrystalline CuInSe 2 absorber surfaces by the so-called Cd partial electrolyte (PE) treatment was studied by synchrotron X-ray photoelectron spectroscopy (SXPS). The Cd PE treatment was found to remove surface indium oxides and hydroxides and segregated sodium compounds. A hydroxide-terminated CdSe surface layer of one monolayer thickness is formed by the partial electrolyte treatment. The reaction mechanism is discussed as substrate site-controlled exchange reaction, where surface indium is removed and replaced by cadmium. Electronically, the Cd PE treated surface is inverted and exhibits a surface barrier which is by 0.2 eV higher than a comparable structure that was prepared by the vacuum deposition of one monolayer of CdS onto clean CuInSe 2

  6. Fabrication of CdS nanowires with increasing anionic precursor by SILAR method

    Science.gov (United States)

    Dariani, R. S.; Salehi, F.

    2016-05-01

    CdS nanowires were fabricated on glass substrate at room temperature by SILAR method with cadmium nitrate cationic and sodium sulfide anionic precursors. The deposition were done at different S:Cd concentration ratios of 1:1, 3:1, 5:1, and 7:1. Nanowires growth procedure was studied in the mentioned concentrations. The number of immersion cycles was kept constant at 15 cycles. EDX analysis showed that in all stoichiometric ratios, S/Cd composition ratio remains at about unity. Our results indicated that S:Cd concentration ratio of 7:1 had the longest nanowires with hexagonal structure. The main objective of this paper was to produce CdS nanowires with increasing concentration of sulfur.

  7. Investigation of CdS clusters in solution for their use as building blocks in hybrid materials

    International Nuclear Information System (INIS)

    Bendova, M.

    2010-01-01

    Semiconductor CdS nanoparticles (NPs) represent a system between bulk solids and molecules with novel properties of matter, originating from 'quantum size effects'. Part of the research is aiming to prepare polymers doped with CdS NPs, so called hybrid materials, in order to introduce photoluminescent properties. Clusters are a special case of NPs with defined molecular structure. The aim of this work is related: to prepare hybrid materials with CdS clusters covalently bound in a polymeric matrix. To this end, functional CdS clusters had to be prepared first, with organic groups on the surface capable of polymerization; then they had to be covalently incorporated into a polymeric matrix. During the whole procedure, the molecular structure of the cluster has to be precisely defined. The investigation proceeded differently. In the first part, the molecular structure of the chosen model clusters was investigated in solution at conditions similar to polymerization. It was shown that solvent coordination plays an important role in the maintainance of the cluster structure. When strongly coordinating solvents were used (DMSO, DMF), the cluster (NMe 4 ) 4 [Cd 10 S 4 (SPh) 16 ] rearranged to bigger clusters and NPs, in weakly coordinating solvents (MeCN) the effect was observable only to low degrees at elevated temperatures. Simultaneously, a byproduct was formed which was characterized as [Cd(SPh) x (DMSO) y ] (2-x) (x =ca. 3) in DMSO. The second investigated compound, 'Cd 10 S 4 (SPh) 12 ', revealed the same behavior in coordinating solvents which led also to crystallization of diverse Cd54 clusters. The compound 'Cd 10 S 4 (SPh) 12 ' was investigated also for different reason: theoretically, it should have four free Cd coordination sites capable of functionalization. It turned out, that it does not have the postulated structure Cd 10 S 4 (SPh) 12 , but that it is a mixture of differently sized CdS clusters. Thus, it could not be used for controlled functionalization

  8. CdS nanoparticles immobilized on porous carbon polyhedrons derived from a metal-organic framework with enhanced visible light photocatalytic activity for antibiotic degradation

    Science.gov (United States)

    Yang, Cao; Cheng, Jianhua; Chen, Yuancai; Hu, Yongyou

    2017-10-01

    The CdS/MOF-derived porous carbon (MPC) composite as an efficient visible-light-driven photocatalyst was prepared through the pyrolysis of ZIF-8 and subsequent growth of CdS. The porous and functionalized MPC enables intimate and discrete growth of CdS nanoparticles. This unique structure not only reduces the bulk recombination owing to nano-size effect of CdS, but also suppresses the surface recombination due to the discrete growth of CdS nanoparticles on MPC polyhedrons, which facilitates electron transfer and charge separation. Moreover, such a composite material possessed good adsorption ability toward the antibiotic pollutants because of the amino-functionalized surface. As a result, the as-prepared CdS/MPC composites showed excellent photocatalytic performance for the antibiotic degradation, significantly improving the photoactivity of CdS. Importantly, the CdS/MPC composite with the CdS loading of 20 wt% exhibited the highest photocatalytic efficiency of approximately 91% and apparent rate constant of 0.024 min-1.

  9. Direct Z-scheme TiO2/CdS hierarchical photocatalyst for enhanced photocatalytic H2-production activity

    Science.gov (United States)

    Meng, Aiyun; Zhu, Bicheng; Zhong, Bo; Zhang, Liuyang; Cheng, Bei

    2017-11-01

    Photocatalytic H2 evolution, which utilizes solar energy via water splitting, is a promising route to deal with concerns about energy and environment. Herein, a direct Z-scheme TiO2/CdS binary hierarchical photocatalyst was fabricated via a successive ionic layer adsorption and reaction (SILAR) technique, and photocatalytic H2 production was measured afterwards. The as-prepared TiO2/CdS hybrid photocatalyst exhibited noticeably promoted photocatalytic H2-production activity of 51.4 μmol h-1. The enhancement of photocatalytic activity was ascribed to the hierarchical structure, as well as the efficient charge separation and migration from TiO2 nanosheets to CdS nanoparticles (NPs) at their tight contact interfaces. Moreover, the direct Z-scheme photocatalytic reaction mechanism was demonstrated to elucidate the improved photocatalytic performance of TiO2/CdS composite photocatalyst. The photoluminescence (PL) analysis of hydroxyl radicals were conducted to provide clues for the direct Z-scheme mechanism. This work provides a facile route for the construction of redox mediator-free Z-scheme photocatalytic system for photocatalytic water splitting.

  10. Default probabilities, CDS premiums and downgrades : A probit-MIDAS analysis

    NARCIS (Netherlands)

    Freitag, L.

    2014-01-01

    This paper examines the relationship between sovereign credit default swaps (CDS) and sovereign rating changes of European countries. To this aim, a new estimator is introduced which merges mixed data sampling (MIDAS) with probit regression. Simulations show that the estimator has good properties in

  11. Simulation of MeV electron energy deposition in CdS quantum dots absorbed in silicate glass for radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Baharin, R; Hobson, P R; Smith, D R, E-mail: ruzalina.baharin@brunel.ac.u [Centre for Sensors and Instrumentation, School of Engineering and Design, Brunel University, Uxbridge UB8 3PH (United Kingdom)

    2010-09-01

    We are currently developing 2D dosimeters with optical readout based on CdS or CdS/CdSe core-shell quantum-dots using commercially available materials. In order to understand the limitations on the measurement of a 2D radiation profile the 3D deposited energy profile of MeV energy electrons in CdS quantum-dot-doped silica glass have been studied by Monte Carlo simulation using the CASINO and PENELOPE codes. Profiles for silica glass and CdS quantum-dot-doped silica glass were then compared.

  12. Simulation of MeV electron energy deposition in CdS quantum dots absorbed in silicate glass for radiation dosimetry

    International Nuclear Information System (INIS)

    Baharin, R; Hobson, P R; Smith, D R

    2010-01-01

    We are currently developing 2D dosimeters with optical readout based on CdS or CdS/CdSe core-shell quantum-dots using commercially available materials. In order to understand the limitations on the measurement of a 2D radiation profile the 3D deposited energy profile of MeV energy electrons in CdS quantum-dot-doped silica glass have been studied by Monte Carlo simulation using the CASINO and PENELOPE codes. Profiles for silica glass and CdS quantum-dot-doped silica glass were then compared.

  13. Preparation of CdS semiconductor nanoarrays in the channels of nickel phosphate VSB-5 nanorods

    International Nuclear Information System (INIS)

    Jian Dunliang; Gao Qiuming; Gao Dongmei; Ruan Meiling; Shi Wei

    2006-01-01

    CdS nanoarrays with the particles' diameter of about 1 nm were assembled in the nanochannels of the host of VSB-5 nanorods. Obvious UV-vis absorption peaks with the onsets of about 350-400 nm were clearly observed. Compared with the band-gap absorption at about 515 nm of the large CdS particles at room temperature, about 115-165 nm of the blue-shifts occurred for the nanoarrays due to the quantum confinement effect

  14. Optical and AFM study of electrostatically assembled films of CdS and ZnS colloid nanoparticles

    International Nuclear Information System (INIS)

    Suryajaya; Nabok, A.; Davis, F.; Hassan, A.; Higson, S.P.J.; Evans-Freeman, J.

    2008-01-01

    CdS and ZnS semiconducting colloid nanoparticles coated with the organic shell, containing either SO 3 - or NH 2 + groups, were prepared using the aqueous phase synthesis. The multilayer films of CdS (or ZnS) were deposited onto glass, quartz and silicon substrates using the technique of electrostatic self-assembly. The films produced were characterized with UV-vis spectroscopy, spectroscopic ellipsometry and atomic force microscopy. A substantial blue shift of the main absorption band with respect to the bulk materials was found for both CdS and ZnS films. The Efros equation in the effective mass approximation (EMA) theoretical model allowed the evaluation of the nanoparticle radius of 1.8 nm, which corresponds well to the ellipsometry results. AFM shows the formation of larger aggregates of nanoparticles on solid surfaces

  15. INTERACTION OF SILVER MOLECULAR CLUSTERS, INTRODUCED BY LOW-TEMPERATURE ION EXCHANGE METHOD, WITH NANOPARTICLES OF CdS IN FLUORINE PHOSPHATE GLASSES

    Directory of Open Access Journals (Sweden)

    N. D. Grazhdanov

    2015-09-01

    Full Text Available Glasses with metallic and semi-conductive nano-particles appear to be perspective non-linear and luminescent materials of photonics. It was shown in theory that composite optical materials containing semi-conductive CdS-core with Ag shell (or vice versa are optimal for enhancement of non-linear Kerr effect. Interaction of such an ensemble of particles leads to the forming of Ag island structures on the CdS particle, and formation of acanthite Ag2S on the two phases border (CdS-Ag is minimal. In glasses synthesis of CdS quantum dots occurred due to thermal treatment close to glass transition temperature; introduction of silver was realized by low-temperature ion exchange (LIE. The main object of this work is investigation of Ag+ -LIE effect on the growth of CdS nano-particles. Two glasses were explored in this work: without CdS (glass 1 and with CdS (glass 2, processed by LIE at the temperature of 320°С for 10, 20 and 30 minutes and subsequent heat treatment at temperatures of 410°С and 420°С. In case of glass 1, intensive luminescence appears as a result of LIE, and subsequent heat treatment results in surface resonance at λ=410 nm. In case of glass 2, absorbance spectra change appears that is specific for formation of acanthite and weak luminescence shifting to long-wavelength region (from 550 to 700 nm as a result of applying LIE and heat treatment. It indicates the growth of CdS quantum dots. Experiment has shown that quantum efficiency increases to 70% for glass 2 containing CdS quantum dots without LIE, while glass that contains silver shows steep decrease of quantum efficiency to 0%. That decrease is caused by formation of acanthite Ag2S on the surface of CdS quantum dot.

  16. Influence of two different template removal methods on the micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres

    International Nuclear Information System (INIS)

    Wang, Han; Jin, Tingting; Zheng, Xing; Jiang, Bo; Zhu, Chaosheng; Yuan, Xiangdong; Zheng, Jingtang; Wu, Mingbo

    2016-01-01

    Hollow cadmium sulfide (CdS) nanospheres of about 260 nm average diameters and about 30 nm shell thickness can be easily synthesized via a sonochemical process, in which polystyrene (PS) nanoparticles were employed as templates. In order to remove the PS templates, both etching and calcination were applied in this paper. The influence of the two different template removal methods on the surface micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres was carefully performed a comparative study. Results of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, FT-IR, thermogravimetric analysis, Brunauer–Emmett–Teller, diffused reflectance spectra, and decolorization experiments showed that the different template removal methods exhibited a significant influence on the surface micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres. The CdS hollow nanospheres as-prepared by etching had pure cubic sphalerite structure, higher –OH content, less defects and exhibited good photocatalytic activity for rhodamine-B, Methylene Blue and methyl orange under UV–vis light irradiation. However, CdS hollow nanospheres obtained by calcination with a hexagonal crystal structure, less –OH content, more defects have shown worse photocatalytic activity. This indicated that surface micromorphology and crystalline phase were mainly factors influencing photocatalytic activity of hollow CdS nanospheres.

  17. Influence of two different template removal methods on the micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Han; Jin, Tingting [China University of Petroleum, State Key Laboratory of Heavy Oil Processing (China); Zheng, Xing, E-mail: znhk113@163.com [Beijing ZNHK Science and Technology Development Co., Ltd. (China); Jiang, Bo; Zhu, Chaosheng [China University of Petroleum, State Key Laboratory of Heavy Oil Processing (China); Yuan, Xiangdong [Baotou Light Industry and Vocational Technical College (China); Zheng, Jingtang, E-mail: jtzheng03@163.com; Wu, Mingbo [China University of Petroleum, State Key Laboratory of Heavy Oil Processing (China)

    2016-11-15

    Hollow cadmium sulfide (CdS) nanospheres of about 260 nm average diameters and about 30 nm shell thickness can be easily synthesized via a sonochemical process, in which polystyrene (PS) nanoparticles were employed as templates. In order to remove the PS templates, both etching and calcination were applied in this paper. The influence of the two different template removal methods on the surface micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres was carefully performed a comparative study. Results of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, FT-IR, thermogravimetric analysis, Brunauer–Emmett–Teller, diffused reflectance spectra, and decolorization experiments showed that the different template removal methods exhibited a significant influence on the surface micromorphology, crystal structure, and photocatalytic activity of hollow CdS nanospheres. The CdS hollow nanospheres as-prepared by etching had pure cubic sphalerite structure, higher –OH content, less defects and exhibited good photocatalytic activity for rhodamine-B, Methylene Blue and methyl orange under UV–vis light irradiation. However, CdS hollow nanospheres obtained by calcination with a hexagonal crystal structure, less –OH content, more defects have shown worse photocatalytic activity. This indicated that surface micromorphology and crystalline phase were mainly factors influencing photocatalytic activity of hollow CdS nanospheres.

  18. Properties of electrospun CdS and CdSe filled poly(methyl methacrylate) (PMMA) nanofibres

    Energy Technology Data Exchange (ETDEWEB)

    Mthethwa, T.P. [University of Johannesburg, Department of Chemical Technology, P.O. Box 17011, Doornfontein 2028 (South Africa); Moloto, M.J., E-mail: mmoloto@uj.ac.za [University of Johannesburg, Department of Chemical Technology, P.O. Box 17011, Doornfontein 2028 (South Africa); De Vries, A.; Matabola, K.P. [CSIR Materials Science and Manufacturing, 4 Gomery avenue, Summerstrand, Port Elizabeth 6000 (South Africa)

    2011-04-15

    Graphical abstract: SEM images of CdS/PMMA showing coiling as loading of CdS nanoparticles is increased. Thermal stability is increased with increase in %loading of both CdS and CdSe nanoparticles. Research highlights: {yields} TOPO-capped CdS and HDA-capped CdSe nanoparticles were synthesized and fully characterized. {yields} The nanoparticles were mixed with the polymer, PMMA using electrospinning technique using 2, 5 and 10% weight loadings. {yields} The mixture was spun to produce fibres with optical and thermal properties showing significant change and also the increase in loading causing bending or spiraling. {yields} Both TEM images for nanoparticles and SEM for fibres shows the morphology and sizes of the particles. -- Abstract: Electrospinning technique was used to fabricate poly(methyl methacrylate) (PMMA) fibres incorporating CdS and CdSe quantum dots (nanoparticles). Different nanoparticle loadings (2, 5 and 10 wt% with respect to PMMA) were used and the effect of the quantum dots on the properties of the fibres was studied. The optical properties of the hybrid composite fibres were investigated by photoluminescence and UV-vis spectrophotometry. Scanning electron microscopy (SEM), X-ray diffraction and FTIR spectrophotometry were also used to investigate the morphology and structure of the fibres. The optical studies showed that the size-tunable optical properties can be achieved in the polymer fibres by addition of quantum dots. SEM images showed that the morphologies of the fibres were dependent on the added amounts of quantum dots. A spiral type of morphology was observed with an increase in the concentration of CdS and CdSe nanoparticles. Less beaded structures and bigger diameter fibres were obtained at higher quantum dot concentrations. X-ray diffractometry detected the amorphous peaks of the polymer and even after the quantum dots were added and the FTIR analysis shows that there was no considerable interaction between the quantum dots and the

  19. Properties of electrospun CdS and CdSe filled poly(methyl methacrylate) (PMMA) nanofibres

    International Nuclear Information System (INIS)

    Mthethwa, T.P.; Moloto, M.J.; De Vries, A.; Matabola, K.P.

    2011-01-01

    Graphical abstract: SEM images of CdS/PMMA showing coiling as loading of CdS nanoparticles is increased. Thermal stability is increased with increase in %loading of both CdS and CdSe nanoparticles. Research highlights: → TOPO-capped CdS and HDA-capped CdSe nanoparticles were synthesized and fully characterized. → The nanoparticles were mixed with the polymer, PMMA using electrospinning technique using 2, 5 and 10% weight loadings. → The mixture was spun to produce fibres with optical and thermal properties showing significant change and also the increase in loading causing bending or spiraling. → Both TEM images for nanoparticles and SEM for fibres shows the morphology and sizes of the particles. -- Abstract: Electrospinning technique was used to fabricate poly(methyl methacrylate) (PMMA) fibres incorporating CdS and CdSe quantum dots (nanoparticles). Different nanoparticle loadings (2, 5 and 10 wt% with respect to PMMA) were used and the effect of the quantum dots on the properties of the fibres was studied. The optical properties of the hybrid composite fibres were investigated by photoluminescence and UV-vis spectrophotometry. Scanning electron microscopy (SEM), X-ray diffraction and FTIR spectrophotometry were also used to investigate the morphology and structure of the fibres. The optical studies showed that the size-tunable optical properties can be achieved in the polymer fibres by addition of quantum dots. SEM images showed that the morphologies of the fibres were dependent on the added amounts of quantum dots. A spiral type of morphology was observed with an increase in the concentration of CdS and CdSe nanoparticles. Less beaded structures and bigger diameter fibres were obtained at higher quantum dot concentrations. X-ray diffractometry detected the amorphous peaks of the polymer and even after the quantum dots were added and the FTIR analysis shows that there was no considerable interaction between the quantum dots and the polymer fibres at low

  20. Cellulose acetate fibers covered by CdS nanoparticles for hybrid solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Cortina, Hugo; Martinez-Alonso, Claudia [Centro de Investigacion en Energia, UNAM, Priv. Xochicalco S/N, Temixco, Morelos 62580 (Mexico); Castillo-Ortega, Monica [Universidad de Sonora, Hermosillo, Sonora 83000 (Mexico); Hu, Hailin, E-mail: hzh@cie.unam.mx [Centro de Investigacion en Energia, UNAM, Priv. Xochicalco S/N, Temixco, Morelos 62580 (Mexico)

    2012-09-20

    In this work cellulose acetate (CA) fibers with a diameter of approximately 1 {mu}m were immersed in a cadmium sulfide (CdS) precursor solution. After 3 h the original white color CA fibers became yellow and maintained the same form, suggesting the deposition of CdS on fiber surface. SEM images showed that CA fibers were covered by uniformly sized CdS nanoparticles of approximately 100 nm. XRD and optical absorption spectra indicated that they contained mostly cubic crystalline phase with the optical band gap of 2.43 eV. CdS coated CA fibers, called CdS(CA) fibers, were dispersed in a polar dispersant (dimethyl sulfoxide, DMSO) and then mixed with a poly(3-hexylthiophene) (P3HT) solution in a non-polar solvent (dichlorobenzene, DCB). The mixture was cast onto a transparent conductive glass substrate (Indium-Tin-Oxide, ITO), and after solvent evaporation a thin layer of CdS(CA)-P3HT composite was formed. It is observed that the volume relation between the polar dispersant and non-polar solvent influences the solubility of the P3HT product in the composite coating and the photovoltaic performance of the corresponding cell as well. The mass ratio between CdS(CA) fibers and P3HT in the composite layer affects the optical absorption of the composite. The best photovoltaic performance was obtained in CdS(CA)-P3HT based cells with a volume relation between DCB and DMSO of 3.5-1, a mass ratio between CdS(CA) and P3HT of 1:1, and a rapid drying process for composite coatings.

  1. Synthesis of anisotropic CdS nanostructures via a single-source route

    CSIR Research Space (South Africa)

    Rajasekhar Pullabhotla, VSR

    2011-02-01

    Full Text Available A cadmium tetrahydroisoquinoline dithiocarbamate (DTC) complex has been used as single-source precursor for the synthesis of highly faceted hexadecylamine (HDA) capped CdS nanoparticles. Hexagonal and close to cubic shaped particles with distinct...

  2. Dicty_cDB: SSL464 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 59525.1 Graphium sarpedon mitochondrial ND5 gene for NADH dehydrogenase 5, partial cds, sample:Cameron Highland, Malaysia...ial ND5 gene for NADH dehydrogenase 5, partial cds, sample:Cameron Highland, Malaysia2,@101. 48 0.072 1 AB05...ND5 gene for NADH dehydrogenase 5, partial cds, sample:Cameron Highland, Malaysia1,@86. 48 0.072 1 AB059521

  3. Formation mechanism of CdS nanoparticles with tunable luminescence via a non-ionic microemulsion route

    International Nuclear Information System (INIS)

    Angelescu, Daniel G.; Munteanu, Gabriel; Anghel, Dan F.; Peretz, Sandu; Maraloiu, Adrian V.; Teodorescu, Valentin S.

    2013-01-01

    We investigated the synthesis of CdS nanoparticles via an optimized water-in-oil microemulsion route that used the non-ionic surfactant-based system H 2 O–n-octane–Brij30/1-octanol. For that purpose, a microemulsion that contained Cd(II) ions (μe1) and another microemulsion that contained S 2− ions (μe2) were combined. To investigate the ways in which the non-ionic microemulsion characteristics controlled the size and emission properties of colloidal CdS quantum dots, μe1 and μe2 with tunable and robust similar structure were prepared. This requirement was fulfilled by matching the water emulsification failure boundary (wefb) of the two microemulsions and carrying out synthesis along this boundary. Dynamic light scattering and fluorescence probe techniques were used to investigate the size and interfacial organization of the microemulsion water droplets, and the CdS nanoparticles were characterized by UV–Vis and static fluorescence spectrometry, TEM and HRTEM. Nanoparticles of diameter 4.5–5.5 nm exhibiting enhanced band edge emission were produced by increasing the water content of the precursor microemulsions. The experimental results were combined with a Monte Carlo simulation approach to demonstrate that growth via coagulation of seed nuclei represented the driving mechanism for the CdS nanoparticle formation in the water-in-oil microemulsion.

  4. Formation mechanism of CdS nanoparticles with tunable luminescence via a non-ionic microemulsion route

    Energy Technology Data Exchange (ETDEWEB)

    Angelescu, Daniel G., E-mail: dangelescu@hotmail.com; Munteanu, Gabriel [Quantum Chemistry and Molecular Structure Laboratory, Romanian Academy, ' Ilie Murgulescu' Institute of Physical Chemistry (Romania); Anghel, Dan F.; Peretz, Sandu [Romanian Academy, ' Ilie Murgulescu' Institute of Physical Chemistry, Colloidal Laboratory (Romania); Maraloiu, Adrian V.; Teodorescu, Valentin S. [National Institute of Materials Physics, Institute of Atomic Physics (Romania)

    2013-01-15

    We investigated the synthesis of CdS nanoparticles via an optimized water-in-oil microemulsion route that used the non-ionic surfactant-based system H{sub 2}O-n-octane-Brij30/1-octanol. For that purpose, a microemulsion that contained Cd(II) ions ({mu}e1) and another microemulsion that contained S{sup 2-} ions ({mu}e2) were combined. To investigate the ways in which the non-ionic microemulsion characteristics controlled the size and emission properties of colloidal CdS quantum dots, {mu}e1 and {mu}e2 with tunable and robust similar structure were prepared. This requirement was fulfilled by matching the water emulsification failure boundary (wefb) of the two microemulsions and carrying out synthesis along this boundary. Dynamic light scattering and fluorescence probe techniques were used to investigate the size and interfacial organization of the microemulsion water droplets, and the CdS nanoparticles were characterized by UV-Vis and static fluorescence spectrometry, TEM and HRTEM. Nanoparticles of diameter 4.5-5.5 nm exhibiting enhanced band edge emission were produced by increasing the water content of the precursor microemulsions. The experimental results were combined with a Monte Carlo simulation approach to demonstrate that growth via coagulation of seed nuclei represented the driving mechanism for the CdS nanoparticle formation in the water-in-oil microemulsion.

  5. Nanostructured CdS thin films deposited by spray pyrolysis method

    Energy Technology Data Exchange (ETDEWEB)

    Kerimova, A.; Bagiyev, E.; Aliyeva, E.; Bayramov, A. [Institute of Physics, Azerbaijan National Academy of Sciences, Baku (Azerbaijan)

    2017-06-15

    Influence of solution pH on the structural and optical properties of CdS films deposited by conventional spray pyrolysis technique was studied. X-Ray Diffraction (XRD), Atomic Force Microscopy (AFM), Photoluminescence spectroscopy (PLS), and Spectroscopic Ellipsometry (SE) methods were used for the characterization of the deposited films. PL spectrum of the film deposited from the solution with pH = 10.2 shows broad-band PL emission located at 460 nm (2.7 eV), which can be attributed to the quantum size effect at grain sizes of <10 nm. No shifts of ε{sub 1} and ε{sub 2} due to the quantum size effect are observed in dielectric function spectra, what can be caused by low concentration of nano-sized (<10 nm) CdS grains. The change in the film properties with the pH of the solution was analyzed in terms of variation of grain sizes of the polycrystalline films. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Synthesis and spectroscopic study of CdS nanoparticles using hydrothermal method

    Science.gov (United States)

    AL-Mamoori, Mohammed H. K.; Mahdi, Dunia K.; Al-Shrefi, Saif M.

    2018-05-01

    In this work, cadmium sulfide nanoparticles (powder) with diameter 50.8 nm was prepared using hydrothermal method. The structural and optical properties of CdS nanoparticles was studied by X-ray diffraction, FESEM, EDS, FTIR, UV-Diffuse Reflectance spectroscopy and Photoluminance spectrum. X-ray diffraction reveal the formation the purity of prepared phase of CdS particles with hexagonal wurtzite structure with particle size 31.8nm by using sheerer equation. The energy dispersion scattering (EDS) examination explains that the sample is composed of a large amount of Cd and S which are exactly CdS nanoparticles and there is a very small trace of (Zn) and (O) element observed because of there is a small pollutions in the measurement place of samples. FESEM shows the spherical shape of nanoparticles with around 50.8 nm diameter. The optical absorption spectral study identified the red shift of the sample in comparison to bulk ZnO in three dimensions. Photoluminance spectrum (PL) at room temperature showed that there are two luminescence peaks at 433.14 nm and 518.21nm. Samples demonstrate a sharp emission band at around 433.18 nm, which is attributed to the typical exciton luminescence. The broad band at 518.21nm which were attributed to the trapped luminescence. The green emission band at 518.21 nm was associated with the emission due to electronic transition from the conduction band to an accepter level due to interstitial sulphur ion.

  7. Enhanced photovoltaic performance of quantum dot-sensitized solar cells with a progressive reduction of recombination using Cu-doped CdS quantum dots

    International Nuclear Information System (INIS)

    Muthalif, Mohammed Panthakkal Abdul; Lee, Young-Seok; Sunesh, Chozhidakath Damodharan; Kim, Hee-Je; Choe, Youngson

    2017-01-01

    Highlights: • Cu-doped CdS QDs were deposited on TiO_2 by SILAR method. • Cu-doped CdS electrodes contributes reduction of charge recombination and longer electron lifetime. • A promising power conversion efficiency of 3% is obtained for the Cu-doped CdS Quantum dot sensitized solar cell. - Abstract: In this article, we have systematically probed the effect of Cu-doping in CdS quantum dots (QDs) to enhance the photovoltaic performance of the quantum dot-sensitized solar cells (QDSSCs). The Cu-doped CdS photoanodes were prepared by successive ionic layer adsorption and reaction (SILAR) method and the corresponding cell devices were fabricated using CuS counter electrodes with a polysulfide electrolyte. The photovoltaic performance results demonstrate that 3 mM Cu-doped CdS QDs based QDSSCs exhibit the efficiency (η) of 3% including J_S_C = 9.40 mA cm"−"2, V_O_C = 0.637 V, FF = 0.501, which are higher than those with bare CdS (η = 2.05%, J_S_C = 7.12 mA cm"−"2, V_O_C = 0.588 V, FF = 0.489). The structural, topographical and optical properties of the thin films have been studied with the help of X-ray diffraction pattern (XRD), atomic force microscopy (AFM) and UV–vis spectrophotometer. Electrochemical impedance spectroscopy (EIS) and open circuit voltage decay (OCVD) measurements indicate that Cu-dopant can inhibit the charge recombination at the photoanode/electrolyte interface and extend the lifetime of electrons. These results reveal that incorporation of copper metal in CdS QDs is a simple and effective method to improve the photovoltaic properties of QDSSCs.

  8. Enhanced photovoltaic performance of quantum dot-sensitized solar cells with a progressive reduction of recombination using Cu-doped CdS quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Muthalif, Mohammed Panthakkal Abdul [Department of Polymer Science and Chemical Engineering, Pusan National University, Geumjeong-Ku, Jangjeong-Dong, Busan 609-735 (Korea, Republic of); Lee, Young-Seok [School of Electrical Engineering, Pusan National University, Geumjeong-Ku, Jangjeong-Dong, Busan 609-735 (Korea, Republic of); Sunesh, Chozhidakath Damodharan [Department of Polymer Science and Chemical Engineering, Pusan National University, Geumjeong-Ku, Jangjeong-Dong, Busan 609-735 (Korea, Republic of); Kim, Hee-Je [School of Electrical Engineering, Pusan National University, Geumjeong-Ku, Jangjeong-Dong, Busan 609-735 (Korea, Republic of); Choe, Youngson, E-mail: choe@pusan.ac.kr [Department of Polymer Science and Chemical Engineering, Pusan National University, Geumjeong-Ku, Jangjeong-Dong, Busan 609-735 (Korea, Republic of)

    2017-02-28

    Highlights: • Cu-doped CdS QDs were deposited on TiO{sub 2} by SILAR method. • Cu-doped CdS electrodes contributes reduction of charge recombination and longer electron lifetime. • A promising power conversion efficiency of 3% is obtained for the Cu-doped CdS Quantum dot sensitized solar cell. - Abstract: In this article, we have systematically probed the effect of Cu-doping in CdS quantum dots (QDs) to enhance the photovoltaic performance of the quantum dot-sensitized solar cells (QDSSCs). The Cu-doped CdS photoanodes were prepared by successive ionic layer adsorption and reaction (SILAR) method and the corresponding cell devices were fabricated using CuS counter electrodes with a polysulfide electrolyte. The photovoltaic performance results demonstrate that 3 mM Cu-doped CdS QDs based QDSSCs exhibit the efficiency (η) of 3% including J{sub SC} = 9.40 mA cm{sup −2}, V{sub OC} = 0.637 V, FF = 0.501, which are higher than those with bare CdS (η = 2.05%, J{sub SC} = 7.12 mA cm{sup −2}, V{sub OC} = 0.588 V, FF = 0.489). The structural, topographical and optical properties of the thin films have been studied with the help of X-ray diffraction pattern (XRD), atomic force microscopy (AFM) and UV–vis spectrophotometer. Electrochemical impedance spectroscopy (EIS) and open circuit voltage decay (OCVD) measurements indicate that Cu-dopant can inhibit the charge recombination at the photoanode/electrolyte interface and extend the lifetime of electrons. These results reveal that incorporation of copper metal in CdS QDs is a simple and effective method to improve the photovoltaic properties of QDSSCs.

  9. Sequential electro-deposition of Bi{sub 2}S{sub 3}/CdS films as co-sensitizer photoanodes for liquid junction solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Jana, Atanu; Hazra, Prasenjit; Hazra, Mukul; Datta, Jayati, E-mail: jayati_datta@rediffmail.com

    2016-11-01

    In this investigation multilayered conjugate films are formulated with Bi{sub 2}S{sub 3} and CdS nanoparticles (NPs) on FTO glass substrate. Thin layer Bi{sub 2}S{sub 3} was deposited and subsequently covered with various levels of CdS coating. Optical properties and XRD analysis of the films show existence of both the compound phases. The morphology of the films studied through electron microscopy reveals coverage of spherical CdS NPs on the network of Bi{sub 2}S{sub 3} NPs. The electrochemical impedance records and performances output characteristics of the n-type films show that the most efficient co-sensitizer matrix is produced with deep coating of CdS on thin layer of Bi{sub 2}S{sub 3}. - Highlights: • Multilayered Bi{sub 2}S{sub 3}/CdS conjugate films are formulated on FTO glass substrate. • Photo-degradation of Bi{sub 2}S{sub 3} is restricted by the coating of CdS layer. • High level of Cd coating on thin layer of Bi{sub 2}S{sub 3} have shown appreciable photocurrent output. • Photo-conversion efficiency of 0.93% is observed for the best conjugate film.

  10. Probing the fungicidal property of CdS quantum dots on Saccharomyces cerevisiae and Candida utilis using MALDI-MS

    Energy Technology Data Exchange (ETDEWEB)

    Manikandan, Muthu; Wu, Hui-Fen, E-mail: hwu@faculty.nsysu.edu.tw [National Sun Yat-Sen University, Department of Chemistry (China)

    2013-07-15

    For the first time, we report the successful application of inhouse synthesized CdS quantum dots (QDs) with particle sizes between 1 and 7 nm exhibiting excellent fungicidal activity based on the interactions with Saccharomyces cerevisiae and Candida utilis. The growth curves and the growth rates of both fungi were established in the presence of three varying concentrations of CdS QDs. It was observed that the CdS QDs were highly inhibitory even at the lowest concentration of 10 mg/L used in this study, while the untreated control cells followed a normal growth pattern in the cases of both Saccharomyces and Candida. MALDI-MS was applied to substantiate the observations obtained by direct cell count method. It was observed that the trend observed in the case of Saccharomyces and Candida was well-represented in the MALDI-MS spectra. This study proposes a mechanism for the first time based on MALDI-MS results, that the CdS QDs interact with the extracellular polymeric substances (EPS) and remove small molecules from EPS layer; on the other hand, it was observed that CdS QDs at all concentrations lead to enrichment of protein signals in MALDI-MS. We have substantiated these results by quantifying the EPS in the control and treated cells and also using TEM to further confirm the results.

  11. Probing the fungicidal property of CdS quantum dots on Saccharomyces cerevisiae and Candida utilis using MALDI-MS

    International Nuclear Information System (INIS)

    Manikandan, Muthu; Wu, Hui-Fen

    2013-01-01

    For the first time, we report the successful application of inhouse synthesized CdS quantum dots (QDs) with particle sizes between 1 and 7 nm exhibiting excellent fungicidal activity based on the interactions with Saccharomyces cerevisiae and Candida utilis. The growth curves and the growth rates of both fungi were established in the presence of three varying concentrations of CdS QDs. It was observed that the CdS QDs were highly inhibitory even at the lowest concentration of 10 mg/L used in this study, while the untreated control cells followed a normal growth pattern in the cases of both Saccharomyces and Candida. MALDI-MS was applied to substantiate the observations obtained by direct cell count method. It was observed that the trend observed in the case of Saccharomyces and Candida was well-represented in the MALDI-MS spectra. This study proposes a mechanism for the first time based on MALDI-MS results, that the CdS QDs interact with the extracellular polymeric substances (EPS) and remove small molecules from EPS layer; on the other hand, it was observed that CdS QDs at all concentrations lead to enrichment of protein signals in MALDI-MS. We have substantiated these results by quantifying the EPS in the control and treated cells and also using TEM to further confirm the results

  12. Subatomic deformation driven by vertical piezoelectricity from CdS ultrathin films.

    Science.gov (United States)

    Wang, Xuewen; He, Xuexia; Zhu, Hongfei; Sun, Linfeng; Fu, Wei; Wang, Xingli; Hoong, Lai Chee; Wang, Hong; Zeng, Qingsheng; Zhao, Wu; Wei, Jun; Jin, Zhong; Shen, Zexiang; Liu, Jie; Zhang, Ting; Liu, Zheng

    2016-07-01

    Driven by the development of high-performance piezoelectric materials, actuators become an important tool for positioning objects with high accuracy down to nanometer scale, and have been used for a wide variety of equipment, such as atomic force microscopy and scanning tunneling microscopy. However, positioning at the subatomic scale is still a great challenge. Ultrathin piezoelectric materials may pave the way to positioning an object with extreme precision. Using ultrathin CdS thin films, we demonstrate vertical piezoelectricity in atomic scale (three to five space lattices). With an in situ scanning Kelvin force microscopy and single and dual ac resonance tracking piezoelectric force microscopy, the vertical piezoelectric coefficient (d 33) up to 33 pm·V(-1) was determined for the CdS ultrathin films. These findings shed light on the design of next-generation sensors and microelectromechanical devices.

  13. Photoelectrochemical detection of copper ions by modulating the growth of CdS quantum dots.

    Science.gov (United States)

    Grinyte, Ruta; Barroso, Javier; Díez-Buitrago, Beatriz; Saa, Laura; Möller, Marco; Pavlov, Valeri

    2017-09-15

    We discovered that copper ions (Cu 2+ ) catalyze the oxidation of cysteine (CSH) by oxygen (O 2 ) to modulate the growth of CSH-capped cadmium sulfide (CdS) nanoparticles (NPs). This new chemical process was applied to sensitive fluorogenic and photoelectrochemical (PEC) detection of Cu 2+ ions in real samples of mineral and tap water using the photocatalytic activity of the resulting NPs. Disposable screen-printed electrodes (SPCEs) modified with electroactive polyvinylpyridine bearing osmium complex (Os-PVP) by cyclic voltammetry (CV) were employed for PEC analytical system. CdS NPs formed during the assay photocatalyze oxidation of 1-thioglycerol (TG) upon application of 0.3 V vs. Ag/AgCl to SPCEs. Os-PVP complex mediated the electron transfer between the electrode surface and CdS NPs. We proved that our assays did not suffer from interference from other ions accompanying Cu 2+ and the sensitivity of our assays covers the European Union standard limit of Cu 2+ ions in drinking water. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Low-temperature processed ZnO and CdS photodetectors deposited by pulsed laser deposition

    International Nuclear Information System (INIS)

    Hernandez-Como, N; Moreno, S; Mejia, I; Quevedo-Lopez, M A

    2014-01-01

    UV-VIS photodetectors using an interdigital configuration, with zinc oxide (ZnO) and cadmium sulfide (CdS) semiconductors deposited by pulsed laser deposition, were fabricated with a maximum processing temperature of 100 °C. Without any further post-growth annealing, the photodetectors are compatible with flexible and transparent substrates. Aluminum (Al) and indium tin oxide (ITO) were investigated as contacts. Focusing on underwater communications, the impact of metal contact (ITO versus Al) was investigated to determine the maximum responsivity using a laser with a 405 nm wavelength. As expected, the responsivity increases for reduced metal finger separation. This is a consequence of reduced carrier transit time for shorter finger separation. For ITO, the highest responsivities for both films (ZnO and CdS) were ∼3 A W −1 at 5 V. On the other hand, for Al contacts, the maximum responsivities at 5 V were ∼0.1 A W −1 and 0.7 A W −1 for CdS and ZnO, respectively. (paper)

  15. The Learning Management System Evolution. CDS Spotlight Report. Research Bulletin

    Science.gov (United States)

    Lang, Leah; Pirani, Judith A.

    2014-01-01

    This Spotlight focuses on data from the 2013 Core Data Service (CDS) to better understand how higher education institutions approach learning management systems (LMSs). Information provided for this Spotlight was derived from Module 8 of the Core Data Service, which contains several questions regarding information systems and applications.…

  16. Pulsed laser induced optical nonlinearities in undoped, copper doped and chromium doped CdS quantum dots

    Science.gov (United States)

    Sharma, Dimple; Malik, B. P.; Gaur, Arun

    2015-04-01

    Quantum dots (QDs) of CdS, Cu doped and Cr doped CdS were synthesized through chemical co- precipitation method. The synthesized QDs have been characterized by x-ray diffraction, ultraviolet visible absorption spectroscopy. The diameters of QDs were calculated using Debye-Scherrer’s formula and Brus equation. They are found to be in 3.5-3.8 nm range. The nonlinear properties has been studied by the open and closed aperture Z-scan technique using frequency double Nd:YAG laser. The nonlinear refractive index (n2), nonlinear absorption coefficient (β), third order nonlinear susceptibilities (χ3) of QDs has been calculated. It has been found that the values of nonlinear parameters are higher for doped QDs than undoped CdS QDs. Hence they can be regarded as potential material for the development of optoelectronics and photonics devices.

  17. Effect of tube depth on the photovoltaic performance of CdS quantum dots sensitized ZnO nanotubes solar cells

    International Nuclear Information System (INIS)

    Yang, Lili; Zhang, Zhiqiang; Yang, Jinghai; Yan, Yongsheng; Sun, Yunfei; Cao, Jian; Gao, Ming

    2012-01-01

    Highlights: ► ZnO nanotubes as photoanode can enhance the energy conversion efficiency. ► ZnO nanotubes with larger surface area can load more CdS QDs to absorb more light. ► ZnO nanotubes can provide two transfer channels for photo-injected carrier. - Abstract: High-density and vertically-aligned ZnO nanotubes (ZNTs) with different depth and ZnO nanorods (ZNRs) were used as photoelectrodes to assemble the CdS quantum dots sensitized solar cells (QDSSCs). In comparison with the CdS sensitized ZNRs solar cell, up to 170% enhancement in energy conversion efficiency was achieved for the CdS sensitized ZNTs under the white light illumination intensity of 100 mW/cm 2 . The investigation about the effects of tube depth on the photovoltaic performance of ZNTs/CdS electrodes revealed that at least two factors induce the enhancement of their conversion efficiency. One is that the higher surface-volume ratio of ZNTs can effectively increase the loading amount of CdS QDs, which can effectively absorb the light. The other is that the outer and inner wall of ZNTs can provide two transfer channels for photo-injected carriers, which can improve the efficiency of current collection.

  18. In situ photodeposition of cobalt on CdS nanorod for promoting photocatalytic hydrogen production under visible light irradiation

    Science.gov (United States)

    Chen, Wei; Wang, Yanhong; Liu, Mei; Gao, Li; Mao, Liqun; Fan, Zeyun; Shangguan, Wenfeng

    2018-06-01

    Non-noble metal Co were loaded on CdS for enhancing photocatalytic activity of water splitting by a simple and efficient in situ photodeposition method. The Co particles with diameter ca. 5 nm were photoreduced and then loaded on the surface of CdS. The loading of Co can not only effectively promote the separation of electrons and holes photoexcited by CdS, but reduce the overpotential of hydrogen evolution as well, thus enhancing photocatalytic activity of water splitting. The highest photocatalytic H2 evolution rate of Co/CdS reaches up to 1299 μmol h-1 under visible light irradiation(λ > 420 nm) when the amount of loading is 1.0 wt%, which is 17 times of that of pure CdS and achieves 80% of that of 0.5 wt%Pt/CdS. This work not only exhibits a pathway to obtain photocatalysts with high photocatalytic activity for hydrogen production, but provides a possibility for the utilization of low cost Co as a substitute for noble metals in photocatalytic hydrogen production.

  19. One-Step Thermolysis Synthesis of Divalent Transition Metal Ions Monodoped and Tridoped CdS and ZnS Luminescent Nanomaterials

    Directory of Open Access Journals (Sweden)

    S. E. Saeed

    2014-01-01

    Full Text Available Mn2+, Co2+, or Ni2+ monodoped CdS (or ZnS and Mn2+-Co2+-Ni2+ tridoped CdS (or ZnS have been successfully synthesized by novel one-step thermolysis method using thiourea as a sulphur source. The synthesized nanomaterials were characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, and scanning electron microscopy (SEM. It is found that the average diameter and morphology of the synthesized samples varied with the nature of dopant ion. The successful doping of Mn2+-Co2+-Ni2+ tridoped ions into the host CdS (or ZnS was proved by the EDX spectra. The luminescence of CdS is only enhanced when monodoped with Mn2+ whereas it is enhanced when ZnS is either monodoped with Mn2+, Co2+, or Ni2+ or tridoped with Mn2+-Co2+-Ni2+. The synthesized samples could therefore offer opportunities for further fundamental research and technological applications.

  20. Effect of impurity inhomogeneity of CdS and CdSe monocrystalline semiconductors on electron absorption of piezoactive ultrasonic waves

    International Nuclear Information System (INIS)

    Ketis, B.P.; Krivka, I.

    1986-01-01

    Relation of observed anomalies (deviations from predictions of theory for homogeneous piezosemiconductor) of electronic absorption coefficient (EAC) of volume, piezoactive acoustic waves (with 15 MHz frequency) in CdS and CdSe hexagonal crystals with electrical heterogeneity is shown experimentally. Results of electron microanalysis of CdS and CdSe piezosemiconductors confirmed their impurity heterogeneity are presented as well as data of investigations into high-frequency conduction and electronic absorption of ultrasonic waves pointing out to volume nature of impurity and electric heterogeneities of monocrystals investigated. Correlation between EAC anomalies and surface density of impurity aggregates (IA) is noted as well as coincidence of impurity and electrical heterogeneities in CdS and CdSe crystals. In CdS crystals the observed anisotropy of high-frequency conduction and volume radioactive ultrasonic waves EAC is attributed to high density and anisotropy of IA space distribution and shape. To explain EAC anomalies, a crystal is simulated with heterogeneous grid of resistances and condensators

  1. Enhanced photocatalytic hydrogen evolution from in situ formation of few-layered MoS2/CdS nanosheet-based van der Waals heterostructures.

    Science.gov (United States)

    Iqbal, Shahid; Pan, Ziwei; Zhou, Kebin

    2017-05-25

    Here we report for the first time that the H 2 bubbles generated by photocatalytic water splitting are effective in the layer-by-layer exfoliation of MoS 2 nanocrystals (NCs) into few layers. The as-obtained few layers can be in situ assembled with CdS nanosheets (NSs) into van der Waals heterostructures (vdWHs) of few-layered MoS 2 /CdS NSs which, in turn, are effective in charge separation and transfer, leading to enhanced photocatalytic H 2 production activity. The few-layered MoS 2 /CdS vdWHs exhibited a H 2 evolution rate of 140 mmol g (CdS) -1 h -1 and achieved an apparent quantum yield of 66% at 420 nm.

  2. Thermal and structural properties of spray pyrolysed CdS thin film

    Indian Academy of Sciences (India)

    Unknown

    Thermal diffusivity and conductivity in these films decrease at least two orders compared with bulk. ... Afifi et al. (1986) prepared evaporated thin film on glass substrate. ... phase of CdS and the identification of the peaks indicate that the film is ...

  3. Shape induced (spherical, sheets and rods) optical and magnetic properties of CdS nanostructures with enhanced photocatalytic activity for photodegradation of methylene blue dye under ultra-violet irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Bilal; Kumar, Sachin; Kumar, Sumeet; Ojha, Animesh K., E-mail: animesh@mnnit.ac.in

    2016-09-15

    CdS nanostructures of different shapes such as, nanoparticles (NPs), nanosheets (NS) and nanorods (NRs) have been synthesized by one step chemical solvothermal method. The synthesized samples were characterized by X-ray diffractometer (XRD), transmission electron microscopy (TEM), photoluminescence (PL) spectroscopy, UV–visible (UV-VIS) spectroscopy, Raman spectroscopy (RS) and vibrating sample magnetometer (VSM) techniques. The effect of shape on optical and magnetic properties of CdS nanostructures was studied. The optical band gap and emission spectra are found to be shape dependent. CdS NRs were found to have high saturation (Ms) magnetization than that of CdS NPs and NS. The role of shape on photocatalytic performance of CdS NPs, NS and NRs was investigated by monitoring the photodegradation of methylene blue (MB) dye under the UV irradiation of wavelength 365 nm. The lower recombination rate of electron-hole pairs and larger surface area as reactive facets for adsorption of MB dye molecules in CdS NS are mainly lead to the better photocatalytic performance of CdS NS compared to NPs and NRs. - Highlights: • Synthesis of CdS nanostructures with different shapes (spherical, rod and sheet) by easy and low cost solvothermal method. • Shape induced optical and magnetic properties of CdS nanostructures have been investigated. • The shapes of nanostructures play an important role for photocatalytic performance of CdS nanostructures.

  4. Electrical transport properties of an isolated CdS microrope composed of twisted nanowires

    Science.gov (United States)

    Yu, Gui-Feng; Yu, Miao; Pan, Wei; Han, Wen-Peng; Yan, Xu; Zhang, Jun-Cheng; Zhang, Hong-Di; Long, Yun-Ze

    2015-01-01

    CdS is one of the important II-VI group semiconductors. In this paper, the electrical transport behavior of an individual CdS microrope composed of twisted nanowires is studied. It is found that the current-voltage ( I- V) characteristics show two distinct power law regions from 360 down to 60 K. Space-charge-limited current (SCLC) theory is used to explain these temperature- and electric-field-dependent I-V curves. The I-V data can be well fitted by this theory above 100 K, and the corresponding carrier mobility, trap energy, and trap concentration are also obtained. However, the I-V data exhibit some features of the Coulomb blockade effect below 80 K.

  5. Electrical transport properties of an isolated CdS microrope composed of twisted nanowires.

    Science.gov (United States)

    Yu, Gui-Feng; Yu, Miao; Pan, Wei; Han, Wen-Peng; Yan, Xu; Zhang, Jun-Cheng; Zhang, Hong-Di; Long, Yun-Ze

    2015-01-01

    CdS is one of the important II-VI group semiconductors. In this paper, the electrical transport behavior of an individual CdS microrope composed of twisted nanowires is studied. It is found that the current-voltage (I-V) characteristics show two distinct power law regions from 360 down to 60 K. Space-charge-limited current (SCLC) theory is used to explain these temperature- and electric-field-dependent I-V curves. The I-V data can be well fitted by this theory above 100 K, and the corresponding carrier mobility, trap energy, and trap concentration are also obtained. However, the I-V data exhibit some features of the Coulomb blockade effect below 80 K.

  6. Surface-roughness-assisted formation of large-scale vertically aligned CdS nanorod arrays via solvothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Minmin [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Yan, Shancheng, E-mail: yansc@njupt.edu.cn [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); School of Geography and Biological Information, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China); Shi, Yi, E-mail: yshi@nju.edu.cn [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Yang, Meng; Sun, Huabin; Wang, Jianyu; Yin, Yao; Gao, Fan [National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China)

    2013-05-15

    Large-scale cadmium sulfide (CdS) nanorod arrays were successfully synthesized on several different substrates through solvothermal reaction. During the growth experiments, we observed that the adhesion strength of the CdS nanorod arrays to different substrates differed dramatically, causing some of the CdS coating being easily flushed away by deionized water (DI water). With doubts and suspicions, we seriously investigate the original morphology of all the substrates by using atomic force microscopy (AFM). The phase, morphology, crystal structure and photoelectric property of all the products were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and current–voltage (I–V) probe station. The growth mechanism of solvothermal reaction was proposed on the basis of all the characterizations. Our approach presents a universal method of liquid phase epitaxy of 1D material on a wide range of substrates of any shape.

  7. Temperature-dependent photoluminescence and mechanism of CdS thin film grown on Si nanoporous pillar array

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Ling Ling [Department of Physics and Laboratory of Material Physics, Zhengzhou University, Zhengzhou 450052 (China); College of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454000 (China); Li, Yan Tao [Department of Physics and Laboratory of Material Physics, Zhengzhou University, Zhengzhou 450052 (China); School of Material Science and Engineering, Henan University of Technology, Zhengzhou 454052 (China); Hu, Chu Xiong [Department of Physics and Laboratory of Material Physics, Zhengzhou University, Zhengzhou 450052 (China); Li, Xin Jian, E-mail: lixj@zzu.edu.cn [Department of Physics and Laboratory of Material Physics, Zhengzhou University, Zhengzhou 450052 (China)

    2015-09-15

    Highlights: • CdS/silicon nanoporous pillar array (CdS/Si-NPA) was prepared by a CBD method. • The PL spectrum of CdS/Si-NPA was measured at different temperatures, from 10 to 300 K. • The PL spectrum was composed of four emission bands, obeying different mechanisms. • The PL degradation with temperature was due to phonon-induced escape of carriers. - Abstract: Si-based cadmium sulfide (CdS) is a prospective semiconductor system in constructing optoelectronic nanodevices, and this makes the study on the factors which may affect its optical and electrical properties be of special importance. Here we report that CdS thin film was grown on Si nanoporous pillar array (Si-NPA) by a chemical bath deposition method, and the luminescent properties of CdS/Si-NPA as well as its mechanism were studied by measuring and analyzing its temperature-dependent photoluminescence (PL) spectrum. The low-temperature measurement disclosed that the PL spectrum of CdS/Si-NPA could be decomposed into four emission bands, a blue band, a green band, a red band and an infrared band. The blue band was due to the luminescence from Si-NPA substrate, and the others originate from the CdS thin film. With temperature increasing, the peak energy, PL intensity and peak profile shape for the PL bands from CdS evolves differently. Through theoretical and fitting analyses, the origins of the green, red and infrared band are attributed to the near band-edge emission, the radiative recombination from surface defects to Cd vacancies and those to S interstitials, respectively. The cause of PL degradation is due to the thermal quenching process, a phonon-induced electron escape but with different activation energies. These results might provide useful information for optimizing the preparing parameters to promote the performance of Si-based CdS optoelectronic devices.

  8. Template-directed nucleation and growth of CdS nanocrystal: the role of helical and nonhelical nanofibers on their shape and size

    International Nuclear Information System (INIS)

    Bose, Partha Pratim; Banerjee, Arindam

    2010-01-01

    This study describes the use of chiral nature of synthetic self-assembled nanofibers for nucleation and growth of Cadmium sulfide (CdS) nanocrystals with different sizes and shapes in room temperature. The templates are built by immobilizing a peptide capping agent on the surface of synthetic self-assembled helical or nonhelical nanofibers and CdS nanocrystals were allowed to grow on them. It is observed that there are differences in shapes and sizes of the nanocrystals depending on the chiral nature of the nanofibers on which they were growing. Even the CdS nanocrystals grown on different chiral and achiral nanofibers differ markedly in their photoluminescence properties. Thus, here we introduce a new way of using chirality of nanofibers to nucleate and grow CdS nanocrystals of different shape, size, and optical property.

  9. Photovoltaic and Impedance Spectroscopy Study of Screen-Printed TiO2 Based CdS Quantum Dot Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    M. Atif

    2015-01-01

    Full Text Available Cadmium sulphide (CdS quantum dot sensitized solar cells (QDSSCs based on screen-printed TiO2 were assembled using a screen-printing technique. The CdS quantum dots (QDs were grown by using the Successive Ionic Layer Adsorption and Reaction (SILAR method. The optical properties were studied by UV-Vis absorbance spectroscopy. Photovoltaic characteristics and impedance spectroscopic measurements of CdS QDSSCs were carried out under air mass 1.5 illuminations. The experimental results of capacitance against voltage indicate a trend from positive to negative capacitance because of the injection of electrons from the Fluorine doped tin oxide (FTO electrode into TiO2.

  10. Influence of wide band gap oxide substrates on the photoelectrochemical properties and structural disorder of CdS nanoparticles grown by the successive ionic layer adsorption and reaction (SILAR) method.

    Science.gov (United States)

    Malashchonak, Mikalai V; Mazanik, Alexander V; Korolik, Olga V; Streltsov, Еugene А; Kulak, Anatoly I

    2015-01-01

    The photoelectrochemical properties of nanoheterostructures based on the wide band gap oxide substrates (ZnO, TiO2, In2O3) and CdS nanoparticles deposited by the successive ionic layer adsorption and reaction (SILAR) method have been studied as a function of the CdS deposition cycle number (N). The incident photon-to-current conversion efficiency (IPCE) passes through a maximum with the increase of N, which is ascribed to the competition between the increase in optical absorption and photocarrier recombination. The maximal IPCE values for the In2O3/CdS and ZnO/CdS heterostructures are attained at N ≈ 20, whereas for TiO2/CdS, the appropriate N value is an order of magnitude higher. The photocurrent and Raman spectroscopy studies of CdS nanoparticles revealed the occurrence of the quantum confinement effect, demonstrating the most rapid weakening with the increase of N in ZnO/CdS heterostructures. The structural disorder of CdS nanoparticles was characterized by the Urbach energy (E U), spectral width of the CdS longitudinal optical (LO) phonon band and the relative intensity of the surface optical (SO) phonon band in the Raman spectra. Maximal values of E U (100-120 meV) correspond to СdS nanoparticles on a In2O3 surface, correlating with the fact that the CdS LO band spectral width and intensity ratio for the CdS SO and LO bands are maximal for In2O3/CdS films. A notable variation in the degree of disorder of CdS nanoparticles is observed only in the initial stages of CdS growth (several tens of deposition cycles), indicating the preservation of the nanocrystalline state of CdS over a wide range of SILAR cycles.

  11. Influence of wide band gap oxide substrates on the photoelectrochemical properties and structural disorder of CdS nanoparticles grown by the successive ionic layer adsorption and reaction (SILAR method

    Directory of Open Access Journals (Sweden)

    Mikalai V. Malashchonak

    2015-11-01

    Full Text Available The photoelectrochemical properties of nanoheterostructures based on the wide band gap oxide substrates (ZnO, TiO2, In2O3 and CdS nanoparticles deposited by the successive ionic layer adsorption and reaction (SILAR method have been studied as a function of the CdS deposition cycle number (N. The incident photon-to-current conversion efficiency (IPCE passes through a maximum with the increase of N, which is ascribed to the competition between the increase in optical absorption and photocarrier recombination. The maximal IPCE values for the In2O3/CdS and ZnO/CdS heterostructures are attained at N ≈ 20, whereas for TiO2/CdS, the appropriate N value is an order of magnitude higher. The photocurrent and Raman spectroscopy studies of CdS nanoparticles revealed the occurrence of the quantum confinement effect, demonstrating the most rapid weakening with the increase of N in ZnO/CdS heterostructures. The structural disorder of CdS nanoparticles was characterized by the Urbach energy (EU, spectral width of the CdS longitudinal optical (LO phonon band and the relative intensity of the surface optical (SO phonon band in the Raman spectra. Maximal values of EU (100–120 meV correspond to СdS nanoparticles on a In2O3 surface, correlating with the fact that the CdS LO band spectral width and intensity ratio for the CdS SO and LO bands are maximal for In2O3/CdS films. A notable variation in the degree of disorder of CdS nanoparticles is observed only in the initial stages of CdS growth (several tens of deposition cycles, indicating the preservation of the nanocrystalline state of CdS over a wide range of SILAR cycles.

  12. Effect of CdS Growth Time on the Optical Properties of One-Pot Preparation of CdS-Ag2S Binary Compounds

    Science.gov (United States)

    Karimipour, M.; Izadian, L.; Molaei, M.

    2018-02-01

    CdS-Ag2S binary nanoparticles were synthesized using a facile one-pot microwave irradiation method. The effect of initial nucleation of CdS quantum dots (QDs) using 3 min, 5 min, and 7 min of microwave irradiation on the optical properties of the final compound was studied. The composition and crystal structure of the compounds were verified using energy dispersive x-ray spectroscopy and x-ray diffraction. They revealed that existence of Ag and Cd elements with an atomic ratio of 0.19 crystalizes in the form of monoclinic Ag2S and hexagonal CdS. Scanning electron microscope images showed a spherical morphology of the resultant compound, and transmission electron microscope images showed the formation of fine particles of CdS-Ag2S composites with an average size of 5-7 nm and 10-14 nm for CdS and Ag2S, respectively. Photoluminescence spectroscopy revealed that the initial growth time of CdS has a crucial effect on the emission of binary compounds such that for 3 min and 5 min of irradiation of CdS solution, the binary compound obtains strong red and considerable near-IR emission (850 nm), but for longer time, it rapidly quenches. The results indicate that the strong red emission can be tuned from 600 nm up to 700 nm with prolonging nucleation time of CdS. This study also emphasized that the origin of red emission strongly depends on the size and defects created in the CdS QDs.

  13. Fast-grown CdS quantum dots: Single-source precursor approach vs microwave route

    Energy Technology Data Exchange (ETDEWEB)

    Fregnaux, Mathieu [Laboratoire de Chimie et Physique: Approche Multi-échelles des Milieux Complexes, Institut Jean Barriol, Université de Lorraine, 1 Boulevard Arago, 57070 Metz (France); Dalmasso, Stéphane, E-mail: stephane.dalmasso@univ-lorraine.fr [Laboratoire de Chimie et Physique: Approche Multi-échelles des Milieux Complexes, Institut Jean Barriol, Université de Lorraine, 1 Boulevard Arago, 57070 Metz (France); Durand, Pierrick [Laboratoire de Cristallographie, Résonance Magnétique et Modélisations, Institut Jean Barriol, Université de Lorraine, UMR CNRS 7036, Faculté des Sciences, BP 70239, 54506 Vandoeuvre lès Nancy (France); Zhang, Yudong [Laboratoire d' Etude des Microstructures et de Mécanique des Matériaux, Université de Lorraine, UMR CNRS 7239, Ile du Saulcy, 57045 Metz cedex 01 (France); Gaumet, Jean-Jacques; Laurenti, Jean-Pierre [Laboratoire de Chimie et Physique: Approche Multi-échelles des Milieux Complexes, Institut Jean Barriol, Université de Lorraine, 1 Boulevard Arago, 57070 Metz (France)

    2013-10-01

    A cross-disciplinary protocol of characterization by joint techniques enables one to closely compare chemical and physical properties of CdS quantum dots (QDs) grown by single source precursor methodology (SSPM) or by microwave synthetic route (MWSR). The results are discussed in relation with the synthesis protocols. The QD average sizes, reproducible as a function of the temperatures involved in the growth processes, range complementarily in 2.8–4.5 nm and 4.5–5.2 nm for SSPM and MWSR, respectively. Hexagonal and cubic structures after X-ray diffraction on SSPM and MWSR grown CdS QDs, respectively, are tentatively correlated to a better crystalline quality of the latter with respect to the further ones, suggested by (i) a remarkable stability of the MWSR grown QDs after exposure to air during several days and (ii) no evidence of their fragmentation during mass spectrometry (MS) analyses, after a fair agreement between size dispersities obtained by transmission electron microscopy (TEM) and MS, in contrast with the discrepancy found for the SSPM grown QDs. Correlatively, a better optical quality is suggested for the MWSR grown QDs by the resolution of n > 1 excitonic transitions in their absorption spectra. The QD average sizes obtained by TEM and deduced from MS are in overall agreement. This agreement is improved for the MWSR grown QDs, taking into account a prolate shape of the QDs also observed in the TEM images. For both series of samples, the excitonic responses vs the average sizes are consistent with the commonly admitted empirical energy-size correspondence. A low energy PL band is observed in the case of the SSPM grown QDs. Its decrease in intensity with QD size increase suggests a surface origin tentatively attributed to S vacancies. In the case of the MWSR grown QDs, the absence of this PL is tentatively correlated to an absence of S vacancies and therefore to the stable behavior observed when the QDs are exposed to air. - Highlights: • Single

  14. CdS-based p-i-n diodes using indium and copper doped CdS films by pulsed laser deposition

    International Nuclear Information System (INIS)

    Hernandez-Como, N; Berrellez-Reyes, F; Mizquez-Corona, R; Ramirez-Esquivel, O; Mejia, I; Quevedo-Lopez, M

    2015-01-01

    In this work we report a method to dope cadmium sulfide (CdS) thin films using pulsed laser deposition. Doping is achieved during film growth at substrate temperatures of 100 °C by sequential deposition of the CdS and the dopant material. Indium sulfide and copper disulfide targets were used as the dopant sources for n-type and p-type doping, respectively. Film resistivities as low as 0.2 and 1 Ω cm were achieved for indium and copper doped films, respectively. Hall effect measurements demonstrated the change in conductivity type from n-type to p-type when the copper dopants are incorporated into the film. The controlled incorporation of indium or copper, in the undoped CdS film, results in substitutional defects in the CdS, which increases the electron and hole concentration up to 4 × 10 18 cm −3 and 3 × 10 20 cm −3 , respectively. The results observed with CdS doping can be expanded to other chalcogenides material compounds by just selecting different targets. With the optimized doped films, CdS-based p-i-n diodes were fabricated yielding an ideality factor of 4, a saturation current density of 2 × 10 −6 A cm −2 and a rectification ratio of three orders of magnitude at ±3 V. (paper)

  15. Dense CdS thin films on fluorine-doped tin oxide coated glass by high-rate microreactor-assisted solution deposition

    Energy Technology Data Exchange (ETDEWEB)

    Su, Yu-Wei, E-mail: suyuweiwayne@gmail.com [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Ramprasad, Sudhir [Energy Processes and Materials Division, Pacific Northwest National Laboratory, Corvallis, OR 9730 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Han, Seung-Yeol; Wang, Wei [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Ryu, Si-Ok [School of Display and Chemical Engineering, Yeungnam University, 214-1 Dae-dong, Gyeonsan, Gyeongbuk 712-749 (Korea, Republic of); Palo, Daniel R. [Barr Engineering Co., Hibbing, MN 55747 (United States); Paul, Brian K. [School of Mechanical, Industrial and Manufacturing Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States); Chang, Chih-hung [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97330 (United States); Microproducts Breakthrough Institute and Oregon Process Innovation Center, Corvallis, Oregon 97330 (United States)

    2013-04-01

    Continuous microreactor-assisted solution deposition is demonstrated for the deposition of CdS thin films on fluorine-doped tin oxide (FTO) coated glass. The continuous flow system consists of a microscale T-junction micromixer with the co-axial water circulation heat exchanger to control the reacting chemical flux and optimize the heterogeneous surface reaction. Dense, high quality nanocrystallite CdS thin films were deposited at an average rate of 25.2 nm/min, which is significantly higher than the reported growth rate from typical batch chemical bath deposition process. Focused-ion-beam was used for transmission electron microscopy specimen preparation to characterize the interfacial microstructure of CdS and FTO layers. The band gap was determined at 2.44 eV by UV–vis absorption spectroscopy. X-ray photon spectroscopy shows the binding energies of Cd 3d{sub 3/2}, Cd 3d{sub 5/2}, S 2P{sub 3/2} and S 2P{sub 1/2} at 411.7 eV, 404.8 eV, 162.1 eV and 163.4 eV, respectively. - Highlights: ► CdS films deposited using continuous microreactor-assisted solution deposition (MASD) ► Dense nanocrystallite CdS films can be reached at a rate of 25.2 [nm/min]. ► MASD can approach higher film growth rate than conventional chemical bath deposition.

  16. Improving the optical and crystalline properties on CdS thin films growth on small and large area by using CBD technique

    Energy Technology Data Exchange (ETDEWEB)

    Albor A, M. L.; Flores M, J. M.; Hernandez V, C.; Contreras P, G.; Mejia G, C.; Rueda M, G. [IPN, Escuela Superior de Fisica y Matematicas, Departamento de Fisica, Unidad Profesional Adolfo Lopez Mateos, Zacatenco, 07738 Ciudad de Mexico (Mexico); Gonzalez T, M. A. [IPN, Escuela Superior de Computo, Departamento de Formacion Basica, Unidad Profesional Adolfo Lopez Mateos, 07738 Ciudad de Mexico (Mexico)

    2016-11-01

    CdS polycrystalline thin films have been used as window layer in solar cells; the optical and crystalline quality of the CdS-partner plays and important role in the photovoltaic device performance. CdS thin films were deposited by using Chemical Bath Deposition. The SnO{sub 2}:F substrates used were chemically treated with HCl (0.1 M) and others were thermally annealed in different atmospheres (Ar and O{sub 2}). The physical properties of CdS thin films were influenced by the HCl treatment, position, size and the substrates movement inside the reaction beaker. The CdS samples were deposited in areas of 4 cm{sup 2}, 50 cm{sup 2} and 100 cm{sup 2}. Finally CdS thin films with thickness of 35-300 nm with good optical and crystalline quality on a uniform morphology were obtained. Transmittance values were obtained for all samples about 85-90 % with an average of gap energy of 2.5 eV. The structural characteristics of the samples were determined by the X-ray diffraction patterns, by means of a D-500 Siemens X-ray system. (Author)

  17. Study of optical phonon modes of CdS nanoparticles using Raman ...

    Indian Academy of Sciences (India)

    Wintec

    Abstract. The reduction in the grain size to nanometer range can bring about radical changes in almost all of the properties of semiconductors. CdS nanoparticles have attracted considerable scientific interest because they exhibit strongly size-dependent optical and electrical properties. In the case of nanostructured ...

  18. Synthesis of hierarchically meso-macroporous TiO2/CdS heterojunction photocatalysts with excellent visible-light photocatalytic activity.

    Science.gov (United States)

    Zhao, Haixin; Cui, Shu; Yang, Lan; Li, Guodong; Li, Nan; Li, Xiaotian

    2018-02-15

    Photocatalysts with a hierarchically porous structure have attracted considerable attention owing to their wide pore size distribution and high surface area, which enhance the efficiency of transporting species to active sites. In this study, hierarchically meso-macroporous TiO 2 photocatalysts decorated with highly dispersed CdS nanoparticles were synthesized via hydrolysis, followed by a hydrothermal treatment. The textural mesopores and interconnected pore framework provided more accessible active sites and efficient mass transport for the photocatalytic process. The light collection efficiency was enhanced because of multiple scattering of incident light in the macropores. Moreover, the formation of a heterojunction between the CdS and TiO 2 nanoparticles extended the photoresponse of TiO 2 to the visible-light range and enhanced the charge separation efficiency. Therefore, the hierarchically meso-macroporous TiO 2 /CdS photocatalysts exhibited excellent photocatalytic activity for the degradation of rhodaming B under visible-light irradiation. Trapping experiments demonstrated that superoxide radicals (O 2 - ) and hydroxyl radicals (OH) were the main active species in photocatalysis. A reasonable photocatalytic mechanism of TiO 2 /CdS heterojunction photocatalysts was also presented. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. A New CDS Structure for High Density FPA with Low Power

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    2015-01-01

    Full Text Available Being an essential part of infrared readout integrated circuit, correlated double sampling (CDS circuits play important roles in both depressing reset noise and conditioning integration signals. To adapt applications for focal planes of large format and high density, a new structure of CDS circuit occupying small layout area is proposed, whose power dissipation has been optimized by using MOSFETs in operation of subthreshold region, which leads to 720 nW. Then the noise calculation model is established, based on which the noise analysis has been carried out by the approaches of transfer function and numerical simulations using SIMULINK and Verilog-A. The results are in good agreement, demonstrating the validity of the present noise calculation model. Thermal noise plays a dominant role in the long wave situation while 1/f noise is the majority in the medium wave situation. The total noise of long wave is smaller than medium wave, both of which increase with the integration capacitor and integration time increasing.

  20. Dichloro (bis[diphenylthiourea] cadmium complex as a precursor for HDA-capped CdS nanoparticles and their solubility in water

    Directory of Open Access Journals (Sweden)

    Tshinyadzo R. Tshikhudo

    2010-07-01

    Full Text Available A single-source precursor route has been explored by using the diphenylthiourea cadmium complex as the source of cadmium sulphide (CdS nanoparticles. The reaction was carried out using hexadecylamine (HDA as the solvent and stabilising agent for the particles. The phenylthiourea complex was synthesised and characterised by means of a combination of spectroscopic techniques, microanalysis and X-ray crystal structural analysis. The diphenylthiourea complex was thermolysed in HDA at 120 °C for 1 h to produce CdS nanoparticles. The CdS nanoparticles prepared were made water-soluble via a ligand exchange reaction involving the use of pyridine to displace HDA. The pyridine was, in turn, replaced by glucose and glucuronic acid. The absorption and emission spectra showed the typical features of quantum confinement for the nanoparticles for both HDA-capped and glucose- or glucuronic acid-capped CdS nanoparticles. The change in the capping groups, from HDA to glucose and glucuronic acid, resulted in absorption and emission features that were almost similar, with only slight red-shifting and tailing.

  1. Influence of substrate temperature, growth rate and TCO substrate on the properties of CSS deposited CdS thin films

    Energy Technology Data Exchange (ETDEWEB)

    Schaffner, J., E-mail: jschaffner@surface.tu-darmstadt.de; Feldmeier, E.; Swirschuk, A.; Schimper, H.-J.; Klein, A.; Jaegermann, W.

    2011-08-31

    The growth of CdS thin films by close space sublimation (CSS) has been systematically studied using an ultra-high vacuum system known as DAISY-SOL in order to understand the basic growth mechanisms and their impact on the film properties. Substrate temperature and deposition rate were varied, and the surface properties of the CdS layer were determined by photoelectron spectroscopy (XPS) without breaking the vacuum. To analyze the influence of the deposition conditions on the layer morphology and crystallographic structure, the films were further characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The SEM and AFM studies show a correlation between the deposition rate and the film morphology. For high deposition rates, edged grain shapes and smoother surfaces were observed than for low deposition rates. CdS films were deposited onto two different commercially available fluorine-doped tin oxide (FTO) substrates. XRD studies show that a high <200> texture of the FTO substrate prefers the CdS growth in <0001> orientation of the hexagonal crystal modification.

  2. CdS nanowires formed by chemical synthesis using conjugated single-stranded DNA molecules

    Science.gov (United States)

    Sarangi, S. N.; Sahu, S. N.; Nozaki, S.

    2018-03-01

    CdS nanowires were successfully grown by chemical synthesis using two conjugated single-stranded (ss) DNA molecules, poly G (30) and poly C (30), as templates. During the early stage of the synthesis with the DNA molecules, the Cd 2+ interacts with Poly G and Poly C and produces the (Cd 2+)-Poly GC complex. As the growth proceeds, it results in nanowires. The structural analysis by grazing angle x-ray diffraction and transmission electron microscopy confirmed the zinc-blende CdS nanowires with the growth direction of . Although the nanowires are well surface-passivated with the DNA molecules, the photoluminescence quenching was caused by the electron transfer from the nanowires to the DNA molecules. The quenching can be used to detect and label the DNAs.

  3. A simple route to shape controlled CdS nanoparticles

    Science.gov (United States)

    Nejo, Ayorinde O.; Nejo, Adeola A.; Pullabhotla, Rajasekhar V. S. R.; Revaprasadu, Neerish

    2013-02-01

    We report the synthesis of CdS nanoparticles in the form of spheres, triangles and wire-like structures. The method involves the reaction of reduced sulfur with a cadmium salt followed by thermolysis in hexadecylamine (HDA). The different shapes were obtained by variation of reaction conditions such as reaction time, temperature and cadmium source. The optical studies show the particles to be quantum confined and luminescent at room temperature.

  4. phylotaR: An Automated Pipeline for Retrieving Orthologous DNA Sequences from GenBank in R

    Directory of Open Access Journals (Sweden)

    Dominic J. Bennett

    2018-06-01

    Full Text Available The exceptional increase in molecular DNA sequence data in open repositories is mirrored by an ever-growing interest among evolutionary biologists to harvest and use those data for phylogenetic inference. Many quality issues, however, are known and the sheer amount and complexity of data available can pose considerable barriers to their usefulness. A key issue in this domain is the high frequency of sequence mislabeling encountered when searching for suitable sequences for phylogenetic analysis. These issues include, among others, the incorrect identification of sequenced species, non-standardized and ambiguous sequence annotation, and the inadvertent addition of paralogous sequences by users. Taken together, these issues likely add considerable noise, error or bias to phylogenetic inference, a risk that is likely to increase with the size of phylogenies or the molecular datasets used to generate them. Here we present a software package, phylotaR that bypasses the above issues by using instead an alignment search tool to identify orthologous sequences. Our package builds on the framework of its predecessor, PhyLoTa, by providing a modular pipeline for identifying overlapping sequence clusters using up-to-date GenBank data and providing new features, improvements and tools. We demonstrate and test our pipeline’s effectiveness by presenting trees generated from phylotaR clusters for two large taxonomic clades: Palms and primates. Given the versatility of this package, we hope that it will become a standard tool for any research aiming to use GenBank data for phylogenetic analysis.

  5. Uniformly dispersed CdS nanoparticles sensitized TiO{sub 2} nanotube arrays with enhanced visible-light photocatalytic activity and stability

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Lingjuan [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Anhui Provincial Key Laboratory of Advanced Functional Materials and Devices, Hefei 230009 (China); Lv, Jun, E-mail: lvjun117@126.com [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Anhui Provincial Key Laboratory of Advanced Functional Materials and Devices, Hefei 230009 (China); Xu, Guangqing; Wang, Yan; Xie, Kui [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Anhui Provincial Key Laboratory of Advanced Functional Materials and Devices, Hefei 230009 (China); Chen, Zhong [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue 639798 (Singapore); Wu, Yucheng, E-mail: ycwu@hfut.edu.cn [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Anhui Provincial Key Laboratory of Advanced Functional Materials and Devices, Hefei 230009 (China)

    2013-12-15

    In this study, TiO{sub 2} nanotube arrays (TiO{sub 2}-NTs) with various intertube spaces were fabricated in the electrolyte with different water contents and the CdS nanoparticles (CdS NPs) were further deposited onto the TiO{sub 2}-NTs as a sensitizer via a sequential chemical bath deposition (S-CBD) method. The FE-SEM, TEM, XRD and XPS results demonstrated that the CdS NPs were uniformly deposited onto the surface of TiO{sub 2}-NTs. It was found that higher water content in electrolyte was in favor of large intertube space and pore size and the uniform deposition of CdS NPs. The photocatalytic degradation of methyl orange was tested with the as-prepared CdS/TiO{sub 2}-NTs under visible light (λ>400 nm). It was found that the photodegradation rate reached as high as 96.7% under visible irradiation for 180 min. In addition, a reasonable degradation rate of 75.8% was achieved even after 5 cycles, suggesting a good photocatalytic stability of the as-prepared CdS/TiO{sub 2}-NTs. - Graphical abstract: The whole sheet of CdS NPs sensitized TiO{sub 2}-NTs with the Ti subtract was used for degradation of methyl orange under visible light (λ>400 nm) on a XPA-7 photochemical reactor. - Highlights: • Intertube space, pore size were controlled by changing water content in electrolyte. • CdS nanoparticles were uniformly deposited onto the surface of TiO{sub 2} nanotubes. • The catalyst with Ti substrate used as a whole was very convenient for recycling. • Visible-light photocatalytic activity and stability were highly enhanced.

  6. Nonlinearity of the refractive index due to an excitonic molecule resonance state in CdS

    International Nuclear Information System (INIS)

    Baumert, R.; Broser, I.; Buschick, K.

    1986-01-01

    The authors report the observation of an intensity-dependent refractive-index nonlinearity in CdS due to a resonance state where an excitonic molecule is created by induced absorption of light. The refractive index n as a function of the incident laser photon energy E is measured directly by light refraction in thin crystal prisms. A renormalized dielectric function describes the measured n(E) spectra well. This strong refractive-index nonlinearity is well suited to produce an optical bistability and to further strengthen the evidence of CdS to be an important material for laser-induced dynamic gratings

  7. PACCMIT/PACCMIT-CDS: identifying microRNA targets in 3' UTRs and coding sequences.

    Science.gov (United States)

    Šulc, Miroslav; Marín, Ray M; Robins, Harlan S; Vaníček, Jiří

    2015-07-01

    The purpose of the proposed web server, publicly available at http://paccmit.epfl.ch, is to provide a user-friendly interface to two algorithms for predicting messenger RNA (mRNA) molecules regulated by microRNAs: (i) PACCMIT (Prediction of ACcessible and/or Conserved MIcroRNA Targets), which identifies primarily mRNA transcripts targeted in their 3' untranslated regions (3' UTRs), and (ii) PACCMIT-CDS, designed to find mRNAs targeted within their coding sequences (CDSs). While PACCMIT belongs among the accurate algorithms for predicting conserved microRNA targets in the 3' UTRs, the main contribution of the web server is 2-fold: PACCMIT provides an accurate tool for predicting targets also of weakly conserved or non-conserved microRNAs, whereas PACCMIT-CDS addresses the lack of similar portals adapted specifically for targets in CDS. The web server asks the user for microRNAs and mRNAs to be analyzed, accesses the precomputed P-values for all microRNA-mRNA pairs from a database for all mRNAs and microRNAs in a given species, ranks the predicted microRNA-mRNA pairs, evaluates their significance according to the false discovery rate and finally displays the predictions in a tabular form. The results are also available for download in several standard formats. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  8. Maximize Institutional Relationships with CRMs. CDS Spotlight Report. ECAR Research Bulletin

    Science.gov (United States)

    Lang, Leah; Pirani, Judith A.

    2014-01-01

    This Spotlight focuses on data from the 2013 Core Data Service (CDS) to better understand how higher education institutions approach customer relationship management (CRM) systems. Information provided for this Spotlight was derived from Module 8 of the Core Data survey, which asked several questions regarding information systems and applications.…

  9. Enhanced charge collection and photocatalysis performance of CdS and PbS nanoclusters co-sensitized TiO{sub 2} porous film

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Miao; Xu, Yanyan; Gong, Zezhou; Tao, Jiajia [School of Physics & Material Science, Anhui University, Hefei 230601 (China); Sun, Zhaoqi, E-mail: szq@ahu.edu.cn [School of Physics & Material Science, Anhui University, Hefei 230601 (China); Lv, Jianguo [School of Electronic & Information Engineering, Hefei Normal University, Hefei, 230601 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Chen, Xiaoshuang [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Jiang, Xishun [School of Physics & Material Science, Anhui University, Hefei 230601 (China); School of Mechanical & Electronic Engineering, Chuzhou University, Chuzhou, 239000 (China); He, Gang; Wang, Peihong; Meng, Fanming [School of Physics & Material Science, Anhui University, Hefei 230601 (China)

    2015-11-15

    A novel translucent TiO{sub 2} porous film was prepared through etched method. The CdS, PbS and CdS/PbS nanoclusters were imbedded on TiO{sub 2} porous film by successive ionic layer adsorption and reaction method. Microstructure, morphology, optical and photoelectron-chemical properties of the as-synthesized thin films were investigated systematically. XRD and morphology analysis showed that PbS or CdS nanoclusters have been attached to the TiO{sub 2} porous films. It was found that the energy band gap of TiO{sub 2} porous film decreased from 3.46 to 3.2 eV after sensitized with nanoclusters. The photocurrent density of ITO/TiO{sub 2} photoelectrode increased from 0.017 to 0.28 mA/cm{sup 2} after co-sensitized with CdS and PbS nanoclusters. Besides, the photoelectrode sensitized with two sorts of nanoclusters showed evident higher photocurrent density than which sensitized just one sort of nanoclusters. The photocurrent density of ITO/TiO{sub 2}/PbS and TO/TiO{sub 2}/CdS photoelectrode was 0.11 mA/cm{sup 2} and 0.22 mA/cm{sup 2} respectively. 0.28 mA/cm{sup 2} can be obtained by ITO/TiO{sub 2}/CdS/PbS photoelectrode. The results showed that the optical and photoelectrochemistry properties and phtotcatalysis performance of TiO{sub 2} porous film were greatly improved by co-sensitized with CdS and PbS nanoclusters. - Graphical abstract: When CdS and PbS were brought in the cascade structure, such a Fermi level alignment causes upward and downward shifts of the band edges for PbS and CdS, respectively. Therefore the resulting band edges for the ITO/TiO{sub 2}/CdS/PbS devices are inferred to have a stepwise structure. The elevated conduction band edge of PbS provides a higher driving force for the injection of photogenerated electrons from PbS to CdS as well as the injection of excited holes from CdS to PbS. Such a structure offers efficient separation and transport of the excited electrons and holes. - Highlights: • Ti films were obtained from direct current

  10. Enhanced solar cell efficiency and stability using ZnS passivation layer for CdS quantum-dot sensitized actinomorphic hexagonal columnar ZnO

    International Nuclear Information System (INIS)

    Chen, Yanli; Tao, Qiang; Fu, Wuyou; Yang, Haibin; Zhou, Xiaoming; Zhang, Yanyan; Su, Shi; Wang, Peng; Li, Minghui

    2014-01-01

    Highlights: • The synthetic of ZnS/CdS QDs/AHC-ZnO photoanode with a simple method. • The power conversion efficiency of the ZnS/CdS QDs/AHC-ZnO is 1.81%. • The effects of photovoltaic performances caused by CdS and ZnS amounts were studied. • ZnS passivation layer enhanced electron lifetime significantly. - Abstract: We report the photoanodes consisting of CdS quantum-dots (QDs) sensitized actinomorphic hexagonal columnar ZnO (CdS QDs/AHC-ZnO) with ZnS passivation layer are applied for solar cells. Simple chemical solution synthesized AHC-ZnO films on transparent conducting glass substrates, and then, AHC-ZnO is functionalized with uniform CdS and ZnS QDs via successive ionic layer adsorption and reaction (SILAR) method. The as-prepared materials were characterized by XRD, SEM, TEM, UV–vis diffused reflectance absorption spectra and photovoltaic performances analysis. Photovoltaic performances results indicate the quantity of CdS QDs as well as the visible light absorption threshold can be effectively controlled by varying the coating cycles during the SILAR process, and the photocurrent density (Jsc) is greatly improved by increasing the amount of ZnS. By optimizing the AHC-ZnO with the amount of CdS and ZnS, the best efficiency of 1.81% was achieved for solar cell under AM 1.5 G illumination with Jsc = 7.44 mA/cm 2 , Voc = 0.57 V and FF = 43%

  11. Hierarchical Layered WS2 /Graphene-Modified CdS Nanorods for Efficient Photocatalytic Hydrogen Evolution.

    Science.gov (United States)

    Xiang, Quanjun; Cheng, Feiyue; Lang, Di

    2016-05-10

    Graphene-based ternary composite photocatalysts with genuine heterostructure constituents have attracted extensive attention in photocatalytic hydrogen evolution. Here we report a new graphene-based ternary composite consisting of CdS nanorods grown on hierarchical layered WS2 /graphene hybrid (WG) as a high-performance photocatalyst for hydrogen evolution under visible light irradiation. The optimal content of layered WG as a co-catalyst in the ternary CdS/WS2 /graphene composites was found to be 4.2 wt %, giving a visible light photocatalytic H2 -production rate of 1842 μmol h(-1)  g(-1) with an apparent quantum efficiency of 21.2 % at 420 nm. This high photocatalytic H2 -production activity is due to the deposition of CdS nanorods on layered WS2 /graphene sheets, which can efficiently suppress charge recombination, improve interfacial charge transfer, and provide reduction active sites. The proposed mechanism for the enhanced photocatalytic activity of CdS nanorods modified with hierarchical layered WG was further confirmed by transient photocurrent response. This work shows that a noble-metal-free hierarchical layered WS2 /graphene nanosheets hybrid can be used as an effective co-catalyst for photocatalytic water splitting. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Effect of gamma-ray irradiation on the size and properties of CdS quantum dots in reverse micelles

    International Nuclear Information System (INIS)

    Bekasova, O.D.; Revina, A.A.; Rusanov, A.L.; Kornienko, E.S.; Kurganov, B.I.

    2013-01-01

    Cadmium sulfide quantum dots 1.3–5.6 nm in size have been synthesized in sodium bis(2-ethylhexy1)sulfosuccinate (AOT)–water–isooctane micellar solutions with various [H 2 O]/[AOT] molar ratios (w=2.5, 5.0 or 10). Gamma irradiation method has been used to change the size and optical properties of quantum dots. It has been found that γ-irradiation reduces the size polydispersity of quantum dots in the micellar system and alters their fluorescent properties. Fluorescence intensity is enhanced after γ-irradiation. The average fluorescence lifetime of single quantum dots sized 5.2±0.4 nm increases from 5.14 to 6.39 ns after γ-irradiation at a dose of 7.9 kGy. To the best of our knowledge, this is the first report on fluorescence lifetime of single CdS quantum dots in micellar solution. - Highlights: • Gamma irradiation method has been used successfully to change the size and optical properties of CdS quantum dots synthesized in micellar solutions. • γ-Irradiation reduces the size polydispersity of quantum dots in the micellar system. • Fluorescence intensity of CdS quantum dots is enhanced after γ-irradiation. • Fluorescence lifetime of single CdS quantum dots increases after γ-irradiation

  13. Visible Light-Induced Degradation of Methylene Blue in the Presence of Photocatalytic ZnS and CdS Nanoparticles

    Directory of Open Access Journals (Sweden)

    Parisa Vaziri

    2012-09-01

    Full Text Available ZnS and CdS nanoparticles were prepared by a simple microwave irradiation method under mild conditions. The obtained nanoparticles were characterized by XRD, TEM and EDX. The results indicated that high purity of nanosized ZnS and CdS was successfully obtained with cubic and hexagonal crystalline structures, respectively. The band gap energies of ZnS and CdS nanoparticles were estimated using UV-visible absorption spectra to be about 4.22 and 2.64 eV, respectively. Photocatalytic degradation of methylene blue was carried out using physical mixtures of ZnS and CdS nanoparticles under a 500-W halogen lamp of visible light irradiation. The residual concentration of methylene blue solution was monitored using UV-visible absorption spectrometry. From the study of the variation in composition of ZnS:CdS, a composition of 1:4 (by weight was found to be very efficient for degradation of methylene blue. In this case the degradation efficiency of the photocatalyst nanoparticles after 6 h irradiation time was about 73% with a reaction rate of 3.61 × 10−3 min−1. Higher degradation efficiency and reaction rate were achieved by increasing the amount of photocatalyst and initial pH of the solution.

  14. Co-sensitization of ZnO by CdS quantum dots in natural dye-sensitized solar cells with polymeric electrolytes to improve the cell stability

    Energy Technology Data Exchange (ETDEWEB)

    Junhom, W.; Magaraphan, R. [Polymer Processing and Polymer Nanomaterials Research Unit, Petroleum and Petrochemical College, Chulalongkorn University, Bangkok (Thailand)

    2015-05-22

    The CdS quantum dots (QDs) were deposited on ZnO layer by chemical bath deposition method to absorb light in the shorter wavelength region and used as photoanode in the dye sensitized solar cell (DSSCs) with natural dye extracted from Noni leaves. Microstructures of CdS-ZnO from various dipping time were characterized by XRD, FE-SEM and EDX. The results showed that the CdS is hexagonal structure and the amount of CdS increases when the dipping time increases. The maximal conversion efficiency of 0.292% was achieved by the DSSCs based on CdS QDs-sensitized ZnO film obtained from 9 min-dipping time. Furthermore, the stability of DSSCs was improved by using polymeric electrolyte. Poly (acrylic acid) (PAA) and Polyacrylamide (PAM) were introduced to CdS QDs-sensitized ZnO film from 9 min-dipping time. Each polymeric electrolyte was prepared by swelling from 0.1-2.0 %w in H2O. The maximal conversion efficiency of 0.207% was achieved for DSSCs based on CdS QDs-sensitized ZnO film with PAM 1.0% and the conversion efficiency was decreased 25% when it was left for1 hr.

  15. Role of the buffer solution in the chemical deposition of CdS films for CIGS solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sooho; Kim, Donguk; Baek, Dohyun; Hong, Byoungyou; Yi, Junsin; Lee, Jaehyeong [Sungkyunkwan University, Suwon (Korea, Republic of); Park, Yongseob [Chosun College of Science and and Technology, Gwangju (Korea, Republic of); Choi, Wonseok [Hanbat National University, Daejeon (Korea, Republic of)

    2014-05-15

    In this work, the effects of NH{sub 4}Ac on the structural and the electro-optical properties of CdS films were investigated. CdS thin films were deposited on soda-lime glass and indium-tin-oxide (ITO) coated glass from a chemical bath containing 0.025 M cadmium acetate, 0 M ∼ 0.2 M ammonium acetate, 0.5 M thiourea, and ammonia. Cadmium acetate was the cadmium source, ammonium acetate served as a buffer, ammonia was the complexing agent, and thiourea was the source of sulfur. A commonly- available chemical bath deposition system was successfully modified to obtain precise control over the pH of the solution at 75 .deg. C during the deposition. Chemically deposited CdS films were studied by using field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), optical transmittance, and electrical resistivity measurements.

  16. Hydrothermal synthesis of functionalized CdS nanoparticles and their application as fluorescence probes in the determination of uracil and thymine

    International Nuclear Information System (INIS)

    Lu Yaxiang; Li Li; Ding Yaping; Zhang Fenfen; Wang Yaping; Yu Weijun

    2012-01-01

    A novel, sensitive, and convenient method for the determination of uracil and thymine by functionalized CdS nanoparticles (NPs) was proposed. CdS NPs were prepared by hydrothermal process and modified with thioglycollic acid (TGA) in aqueous solution. The fluorescence intensity of functionalized CdS NPs was quenched in the presence of uracil or thymine. Under optimal conditions, the relative fluorescence intensity (F 0 /F) was proportional to the concentration in the range of 9.0x10 -6 -1.0x10 -4 mol/L for uracil (r=0.9985) and 8.8x10 -7 -1.5x10 -4 mol/L for thymine (r=0.9960). The corresponding detection limits were 9.6x10 -7 mol/L and 3.2x10 -7 mol/L, respectively. In addition, the possible quenching mechanism was also discussed. - Highlights: → Nano-CdS fluorescence probes were synthesized with good optical properties. → Uracil and thymine were successfully detected by CdS fluorescence probes. → Wide linear ranges and low detection limits were obtained.

  17. Tuning band alignment by CdS layers using a SILAR method to enhance TiO2/CdS/CdSe quantum-dot solar-cell performance.

    Science.gov (United States)

    Zhang, Bingkai; Zheng, Jiaxin; Li, Xiaoning; Fang, Yanyan; Wang, Lin-Wang; Lin, Yuan; Pan, Feng

    2016-04-28

    We report tuning band alignment by optimized CdS layers using a SILAR method to achieve the recorded best performance with about 6% PCE in TiO2/CdS/CdSe QDSSCs. Combining experimental and theoretical studies, we find that a better lattices match between CdS and TiO2 assists the growth of CdSe, and the combined effect of charge transfer and surface dipole moment at the TiO2/CdS/CdSe interface shifts the energy levels of TiO2 upward and increases Voc of the solar cells. More importantly, the band gap of CdS buffer layers is sensitive to the distortion induced by lattice mismatch and numbers of CdS layers. For example, the barrier for charge transfer disappears when there are more than 4 layers of CdS, facilitating the charge injection from CdSe to TiO2.

  18. La Doping of CdS for Enhanced CdS/CdSe Quantum Dot Cosensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Xiaolei Qi

    2015-01-01

    Full Text Available CdS/CdSe system of quantum dot cosensitized solar cells (QDCSCs is one of the most attractive structures for high-efficiency due to its effect of level adjusting. However, the stepwise structure formed between levels of CdS and CdSe has a limitation for enhancing the efficiencies. Metal ions doping in quantum dots have emerged as a common way for changing the Fermi level, band gap, and conductance. Here we report an innovative concept for the rare earth materials La-doped of the CdS layer in the CdS/CdSe QDCSCs by means of the successive ionic layer adsorption and reaction (SILAR. Then we tested that La doped quantum dots can help more electrons accumulate in CdS film, which makes the Fermi level shift up and form a stepped structure. This method leads to enhanced absorption intensity, obviously increasing current density in CdS/CdSe QDCSCs. Our research is a new exploration for improving efficiencies of quantum dot sensitized solar cells.

  19. Growth of CdS nanoparticles by chemical method and its ...

    Indian Academy of Sciences (India)

    carbon film supported on the copper grid and was kept for some time for drying. Transmission electron ... Wang et al obtained CdS nanoparticles having a band gap of. 2.79 eV [21]. .... [16] S Yu, Y Wu, J Yang, Z Han, Y Quan, X Liu and Y Xie, Chem. Matter 10 ... [22] U K Gautam, R Seshadri and C N R Rao, Chem. Phys. Lett.

  20. Chemical bath deposition of CdS thin films doped with Zn and Cu

    Indian Academy of Sciences (India)

    Abstract. Zn- and Cu-doped CdS thin films were deposited onto glass substrates by the chemical bath technique. ... Cadmium sulfide; chemical bath deposition; doping; optical window. 1. ..... at low temperature (10 K), finding similar trends than.

  1. Thermal and optical properties of polycrystalline CdS thin films deposited by the gradient recrystallization and growth (GREG) technique using photoacoustic methods

    International Nuclear Information System (INIS)

    Albor-Aguilera, M.L.; Gonzalez-Trujillo, M.A.; Cruz-Orea, A.; Tufino-Velazquez, M.

    2009-01-01

    In this work we report the study of the thermal and optical properties of polycrystalline CdS thin films deposited by the gradient recrystallization and growth technique. CdS films were grown on pyrex glass substrates. These studies were carried out using an open photoacoustic cell made out of an electret microphone. From X-ray diffraction, atomic force microscope and photoluminescence measurements we observed polycrystalline CdS films with good morphology and crystalline quality. We obtained a thermal diffusivity coefficient of our samples with values ranging from 3.15 to 3.89 x 10 -2 cm 2 /s. For comparison, we measured a value of 1.0 x 10 -2 cm 2 /s for the thermal diffusivity coefficient of a CdS single crystal. We measured an energy gap value of 2.42 eV for our samples by using a photoacoustic spectroscopy system

  2. Wrinkle-free atomically thin CdS nanosheets for photocatalytic hydrogen evolution

    Science.gov (United States)

    Pan, Ziwei; Li, Junnan; Zhou, Kebin

    2018-05-01

    Two-dimensional (2D) nanosheets of atomic thickness have attracted extensive research interest recently. In this work, atomically thin (0.7 nm) flat CdS (F-CdS) nanosheets of several tens of micrometers in lateral size were synthesized by a solvent-thermal method. The as-synthesized F-CdS could maintain flat morphology well in solution, while irreversible wrinkles could be generated after drying, forming wrinkled CdS (W-CdS) samples. It was revealed that the formation of wrinkles could reduce light absorbance, narrow the band gap, move down the conduction band position and accelerate electron–hole recombination. As photocatalysts, the F-CdS achieved a photocatalytic H2 evolution rate of 138.7 mmol g‑1 h‑1 without any co-catalyst under visible light, which was much higher than that of the W-CdS sample (with an H2 evolution rate of only 52.8 mmol g‑1 h‑1). This work demonstrates that great attention should be paid to the wrinkles in 2D materials as photocatalysts.

  3. General practitioners' attitudes and preparedness towards Clinical Decision Support in e-Prescribing (CDS-eP adoption in the West of Ireland: a cross sectional study

    Directory of Open Access Journals (Sweden)

    O'Brien Timothy

    2010-01-01

    Full Text Available Abstract Background Electronic clinical decision support (CDS is increasingly establishing its role in evidence-based clinical practice. Considerable evidence supports its enhancement of efficiency in e-Prescribing, but some controversy remains. This study evaluated the practicality and identified the perceived benefits of, and barriers to, its future adoption in the West of Ireland. Methods This cross sectional study was carried out by means of a 27-part questionnaire sent to 262 registered general practitioners in Counties Galway, Mayo and Roscommon. The survey domains encompassed general information of individual's practice, current use of CDS and the practitioner's attitudes towards adoption of CDS-eP. Descriptive and inferential analyses were performed to analyse the data collected. Results The overall response rate was 37%. Nearly 92% of respondents employed electronic medical records in their practice. The majority acknowledged the value of electronic CDS in improving prescribing quality (71% and reducing prescribing errors (84%. Despite a high degree of unfamiliarity (73%, the practitioners were open to the use of CDS-eP (94% and willing to invest greater resources for its implementation (62%. Lack of a strategic implementation plan (78% is the main perceived barrier to the incorporation of CDS-eP into clinical practice, followed by i lack of financial incentives (70%, ii lack of standardized product software (61%, iii high sensitivity of drug-drug interaction or medication allergy markers (46%, iv concern about overriding physicians' prescribing decisions(44% and v lack of convincing evidence on the systems' effectiveness (22%. Conclusions Despite favourable attitudes towards the adoption of CDS-eP, multiple perceived barriers impede its incorporation into clinical practice. These merit further exploration, taking into consideration the structure of the Irish primary health care system, before CDS-eP can be recommended for routine

  4. Surfactant-assisted hydrothermal synthesis of CdS nanotips: optical and magnetic properties

    International Nuclear Information System (INIS)

    Mondal, Biswajit; Saha, Shyamal Kumar

    2012-01-01

    CdS nanotips with size 5–8 nm are synthesized by hydrothermal process using polyacrylamide (PAM) as surfactant. The shape of nanocrystals (NCs) changes from particles to nanorods or nanotips depending upon the amount of PAM used. Optical properties of the CdS NCs vary with hydrothermal temperature (T H ) due to formation of “S” vacancies. The Rietveld refinement of XRD data shows that “S” site occupancy decreases with increase in T H and amount of PAM indicating the formation of “S” vacancies. Size-dependent magnetic properties in these NCs indicate that the micron-size rods are diamagnetic in nature while the microrods ended with sharp tips show ferromagnetism even at room temperature. The origin of this ferromagnetism in nanotips is explained by the variation in density of “S” defects at the nanotips as well as in the nanorods. These ferromagnetic nanotips grown in the rods as side growth have potential applications in magnetic force microscopes.

  5. CdS nanorods/organic hybrid LED array and the piezo-phototronic effect of the device for pressure mapping.

    Science.gov (United States)

    Bao, Rongrong; Wang, Chunfeng; Dong, Lin; Shen, Changyu; Zhao, Kun; Pan, Caofeng

    2016-04-21

    As widely applied in light-emitting diodes and optical devices, CdS has attracted the attention of many researchers due to its nonlinear properties and piezo-electronic effect. Here, we demonstrate a LED array composed of PSS and CdS nanorods and research the piezo-photonic effect of the array device. The emission intensity of the device depends on the electron-hole recombination at the interface of the p-n junction which can be adjusted using the piezo-phototronic effect and can be used to map the pressure applied on the surface of the device with spatial resolution as high as 1.5 μm. A flexible LED device array has been prepared using a CdS nanorod array on a Au/Cr/kapton substrate. This device may be used in the field of strain mapping using its high pressure spatial-resolution and flexibility.

  6. Enhanced photovoltaic performance of quantum dot-sensitized solar cells with a progressive reduction of recombination using Cu-doped CdS quantum dots

    Science.gov (United States)

    Muthalif, Mohammed Panthakkal Abdul; Lee, Young-Seok; Sunesh, Chozhidakath Damodharan; Kim, Hee-Je; Choe, Youngson

    2017-02-01

    In this article, we have systematically probed the effect of Cu-doping in CdS quantum dots (QDs) to enhance the photovoltaic performance of the quantum dot-sensitized solar cells (QDSSCs). The Cu-doped CdS photoanodes were prepared by successive ionic layer adsorption and reaction (SILAR) method and the corresponding cell devices were fabricated using CuS counter electrodes with a polysulfide electrolyte. The photovoltaic performance results demonstrate that 3 mM Cu-doped CdS QDs based QDSSCs exhibit the efficiency (η) of 3% including JSC = 9.40 mA cm-2, VOC = 0.637 V, FF = 0.501, which are higher than those with bare CdS (η = 2.05%, JSC = 7.12 mA cm-2, VOC = 0.588 V, FF = 0.489). The structural, topographical and optical properties of the thin films have been studied with the help of X-ray diffraction pattern (XRD), atomic force microscopy (AFM) and UV-vis spectrophotometer. Electrochemical impedance spectroscopy (EIS) and open circuit voltage decay (OCVD) measurements indicate that Cu-dopant can inhibit the charge recombination at the photoanode/electrolyte interface and extend the lifetime of electrons. These results reveal that incorporation of copper metal in CdS QDs is a simple and effective method to improve the photovoltaic properties of QDSSCs.

  7. Gezi Parkı Olaylarının Türkiye Kredi Temerrüt Swapları (CDS Üzerine Etkisi (The Effects of Gezi Park Protests on Turkey’s Credit Default Swaps (CDS

    Directory of Open Access Journals (Sweden)

    Musa GÜN

    2016-03-01

    Full Text Available Credit default swap is also referred to as a credit derivative contract where the counterparty of the swap makes payments up until the maturity date of a financial contract. In this study, whether Gezi Park events which happened in 2013 are on a significant impact on Turkey credit default swap spread or not tested with the VAR(Vector Auto-Regressive method. In the analysis, investigated the long-term relationship with Johansen co-integration test and causality with Granger test. In addition, variance decomposition and impulse response analysis are performed. According to the results found significant correlations between Gezi Park events and CDS and also Eurobonds interest, the BIST 100 index, a basket of currencies with CDS spreads have been identified.

  8. GenBank blastx search result: AK104780 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104780 001-039-C06 AY026914.1 Pseudomonas putida strain P111 czrBA operon, partial sequence; ben operon... and ant operon, complete sequence; and catRBCA operon, partial sequence; and unknown gene.|BCT BCT 3e-11 +2 ...

  9. GenBank blastx search result: AK287557 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287557 J065021C17 AY026914.1 AY026914 Pseudomonas putida strain P111 czrBA operon..., partial sequence; ben operon and ant operon, complete sequence; and catRBCA operon, partial sequence; and unknown gene. BCT 0.0 0 ...

  10. GenBank blastx search result: AK109330 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK109330 006-201-C10 AY026914.1 Pseudomonas putida strain P111 czrBA operon, partial sequence; ben operon... and ant operon, complete sequence; and catRBCA operon, partial sequence; and unknown gene.|BCT BCT 3e-11 +2 ...

  11. GenBank blastx search result: AK289020 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289020 J090090F09 AY026914.1 AY026914 Pseudomonas putida strain P111 czrBA operon..., partial sequence; ben operon and ant operon, complete sequence; and catRBCA operon, partial sequence; and unknown gene. BCT 0.0 0 ...

  12. Dicty_cDB: AFB241 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available esis elongation factor 1-alpha (tef2) gene, partial cds. 682 0.0 2 AF157274 |AF157274.1 Phascolomyces arti...culosus translation elongation factor 1-alpha (EF-1alpha) gene, partial cds. 105 2e

  13. The studies of radiation distorations in CdS single crystals by using a proton back-scattering method

    International Nuclear Information System (INIS)

    Grigor'ev, A.N.; Dikij, N.P.; Matyash, P.P.; Nikolajchuk, L.I.; Pivovar, L.I.

    1974-01-01

    The radiation defects in semiconducting CdS single crystals induced during doping with 140 keV Na ions (10 15 -2.10 16 ion/cm 2 ) were studied by the orientation dependence of 700 keV proton backscattering. The absence of discrete peaks in the scattered proton eneryg spectra indicates a small contribution of direct scattering at large angles. The defects formed during doping increase the fractionof dechanneled particles, which are then scattered at large anlges. No amorphization of CdS was observed at high Na ion dose 2x10 16 ion/cm 2

  14. Photoelectrochemical property of CdS and PbS cosensitized on the TiO2 array by novel successive ionic layer adsorption and reaction method

    International Nuclear Information System (INIS)

    Lv, Pin; Fu, Wuyou; Mu, Yannan; Sun, Hairui; Su, Shi; Chen, Yanli; Yao, Huizhen; Ding, Dong; Liu, Tie; Wang, Jun; Yang, Haibin

    2015-01-01

    Highlights: • (CdS + PbS)/TiO 2 NTWs array was firstly synthesized by novel SILAR (N-SILAR) method. • N-SILAR method could shorten time, simplify procedure, lower cost. • (CdS + PbS)/TiO 2 NTWs contain both PbS/CdS/TiO 2 and CdS/PbS/TiO 2 composites structure. • (CdS + PbS)/TiO 2 NTWs can improve electron transport and reduce chemical erosion both. • The photocurrent of (CdS + PbS)/TiO 2 NTWs was 4.1 mA/cm 2 —8 times as high as TiO 2 . - Abstract: TiO 2 film materials have very wide applications in photovoltaic conversion techniques. And, TiO 2 nanotubes array film with nanowires directly formed on top (denoted as TiO 2 NTWs) was prepared by the anodization method. CdS and PbS quantum dots (QDs) were firstly cosensitized on the TiO 2 NTWs array (denoted as (CdS + PbS)/TiO 2 NTWs) by novel successive ionic layer adsorption and reaction (N-SILAR), which only needed a cation mixed solution containing Cd 2+ and Pb 2+ and an anionic solution containing S 2− . This N-SILAR method can not only effectively shorten the experimental time, simplify the experiment procedure and reduce the experiment cost, but also make the material of (CdS + PbS)/TiO 2 NTWs possess the advantages of improving electron transport and reducing chemical erosion. Moreover, the photocurrent of (CdS + PbS)/TiO 2 NTWs was 4.1 mA/cm 2 under an illumination of 100 mW/cm 2 . The most eye-popping part was that the result was 8 times higher than that of the bare TiO 2 NTWs array. The result of photoelectrochemical measurements indicated that this novel material had a potential application in photovoltaic devices

  15. PACCMIT/PACCMIT-CDS: identifying microRNA targets in 3′ UTRs and coding sequences

    Science.gov (United States)

    Šulc, Miroslav; Marín, Ray M.; Robins, Harlan S.; Vaníček, Jiří

    2015-01-01

    The purpose of the proposed web server, publicly available at http://paccmit.epfl.ch, is to provide a user-friendly interface to two algorithms for predicting messenger RNA (mRNA) molecules regulated by microRNAs: (i) PACCMIT (Prediction of ACcessible and/or Conserved MIcroRNA Targets), which identifies primarily mRNA transcripts targeted in their 3′ untranslated regions (3′ UTRs), and (ii) PACCMIT-CDS, designed to find mRNAs targeted within their coding sequences (CDSs). While PACCMIT belongs among the accurate algorithms for predicting conserved microRNA targets in the 3′ UTRs, the main contribution of the web server is 2-fold: PACCMIT provides an accurate tool for predicting targets also of weakly conserved or non-conserved microRNAs, whereas PACCMIT-CDS addresses the lack of similar portals adapted specifically for targets in CDS. The web server asks the user for microRNAs and mRNAs to be analyzed, accesses the precomputed P-values for all microRNA–mRNA pairs from a database for all mRNAs and microRNAs in a given species, ranks the predicted microRNA–mRNA pairs, evaluates their significance according to the false discovery rate and finally displays the predictions in a tabular form. The results are also available for download in several standard formats. PMID:25948580

  16. Structural, optical and photovoltaic properties of P3HT and Mn-doped CdS quantum dots based bulk hetrojunction hybrid layers

    Science.gov (United States)

    Jabeen, Uzma; Adhikari, Tham; Pathak, Dinesh; Shah, Syed Mujtaba; Nunzi, Jean-Michel

    2018-04-01

    Cadmium sulphide (CdS) and Mn-doped CdS nanocrystals were synthesized by co-precipitation method. The nanocrystals were characterized by Fluorescence, Fourier Transformed Infra-red Spectrometer (FTIR), UV-Visible, X-ray diffraction (XRD), X-ray photoelectron spectrometer (XPS), Field Emission Scanning Electron Microscope (FESEM), and High Resolution Transmission Electron Microscope (HRTEM). A considerable blue shift of absorption band with respect to the cadmium sulphide was observed by the Mn concentration (0.5 M) in the doped sample with decreasing the size of nanocrystals. Other reason for this may be Mn doping. Subsequently the band gap was altered from 2.11 to 2.21 eV due to quantum confinement effect. Scanning electron microscope supplemented with EDAX was operated to find grain size and chemical composition of the synthesized nanomaterials. The PL spectrum of Mn-doped CdS nanocrystals displays three PL bands the first one, within the range of 500 nm and the second band at 537 nm, and the third one around 713 nm is labelled red band emission due to attributed to a 4T1→6A1 transition within the 3d shell of divalent manganese. XRD analysis showed that the material was in cubic crystalline state. A comparative study of surfaces of un-doped and metal doped CdS nanocrystals were investigated using X-ray Photoelectron Spectroscopy (XPS). The synthesized nanomaterial in combination with polymer, poly (3-hexyl thiophene) was operated in the construction of photovoltaic cells. The photovoltaic devices with CdS nanocrystals exhibited power conversion efficiency of 0.34% without annealing and 0.38% with annealing. However, the power conversion efficiency was enhanced by a factor of 0.35 without annealing and 0.42 with annealing with corporation of Mn impurity in CdS lattice. Atomic Force Microscopy was employed for morphology and packing behavior of blend of nanocrystals with organic polymer.

  17. Flexible pressure sensor based on graphene aerogel microstructures functionalized with CdS nanocrystalline thin film

    Science.gov (United States)

    Plesco, Irina; Dragoman, Mircea; Strobel, Julian; Ghimpu, Lidia; Schütt, Fabian; Dinescu, Adrian; Ursaki, Veaceslav; Kienle, Lorenz; Adelung, Rainer; Tiginyanu, Ion

    2018-05-01

    In this paper, we report on functionalization of graphene aerogel with a CdS thin film deposited by magnetron sputtering and on the development of flexible pressure sensors based on ultra-lightweight CdS-aerogel nanocomposite. Analysis by scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray analysis disclose the uniform deposition of nanocrystalline CdS films with quasi-stoichiometric composition. The piezoresistive response of the aforementioned nanocomposite in the pressure range from 1 to 5 atm is found to be more than one order of magnitude higher than that inherent to suspended graphene membranes, leading to an average sensitivity as high as 3.2 × 10-4 kPa-1.

  18. p–n junction improvements of Cu{sub 2}ZnSnS{sub 4}/CdS monograin layer solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Kauk-Kuusik, M., E-mail: marit.kauk-kuusik@ttu.ee [Department of Materials Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Timmo, K.; Danilson, M.; Altosaar, M.; Grossberg, M. [Department of Materials Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Ernits, K. [crystalsol OÜ, Akadeemia tee 15a, 12618 Tallinn (Estonia)

    2015-12-01

    Highlights: • S, Sn–O and/or Sn–Br species are formed on the CZTS crystal's after Br-etching. • KCN etching remained oxides and bromides on the surface until CdS deposition. • The Br-etched devices exhibit a “crossover” between the dark and the light I–V curve. - Abstract: In this work we studied the influence of oxidative etching of CZTS monograin surface to the performance of CZTS monograin layer solar cells. The chemistry of CZTS monograin powder surfaces submitted to bromine in methanol and KCN aqueous solutions was investigated by X-ray photoelectron spectroscopy. After bromine etching, elemental sulfur, Sn–O and/or Sn–Br species are formed on the CZTS crystal surface. Sulfur is completely removed by subsequent KCN etching, but oxides and bromides remained on the surface until CdS deposition. These species dissolve in alkaline solution and influence properties of CdS. The conversion efficiency of solar cells improved after the chemical etching prior to CdS deposition and the effect can be attributed to the change of the absorber material crystals surface composition and properties suitable for the effective p–n junction formation. The best CZTS monograin layer solar cell showed conversation efficiency of 7.04% (active area 9.38%).

  19. Preparation and photovoltaic properties of CdS quantum dot-sensitized solar cell based on zinc tin mixed metal oxides.

    Science.gov (United States)

    Cao, Jiupeng; Zhao, Yifan; Zhu, Yatong; Yang, Xiaoyu; Shi, Peng; Xiao, Hongdi; Du, Na; Hou, Wanguo; Qi, Genggeng; Liu, Jianqiang

    2017-07-15

    The present study reports a new type of quantum dot sensitized solar cells (QDSSCs) using the zinc tin mixed metal oxides (MMO) as the anode materials, which were obtained from the layered double hydroxide (LDH) precursor. The successive ionic layer adsorption and reaction (SILAR) method is applied to deposit CdS quantum dots. The effects of sensitizing cycles on the performance of CdS QDSSC are studied. Scanning electron microscopy (SEM), Transmission electron microscope (TEM) and X-ray diffraction (XRD) are used to identify the surface profile and crystal structure of the mixed metal oxides anode. The photovoltaic performance of the QDSSC is studied by the electrochemical method. The new CdS QDSSC exhibits power conversion efficiency (PCE) up to 0.48% when the anode was sensitized for eight cycles. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Exploring the crystallization landscape of cadmium bis(N-hydroxyethyl, N-isopropyldithiocarbamate), Cd[S2CN(iPr)CH2CH2OH]2

    International Nuclear Information System (INIS)

    Tan, Yee Seng; Halim, Siti Nadiah Abdul; Tiekink, Edward R.T.; Sunway Univ., Bandar Sunway

    2016-01-01

    Crystallization of Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 from ethanol yields the coordination polymer [{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 }.EtOH] ∞ (1) within 3 h. When the solution is allowed to stand for another hour, the needles begin to dissolve and prisms emerge of the supramolecular isomer (SI), binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 .2EtOH (2). These have been fully characterized spectroscopically and by X-ray crystallography. Polymeric 1 has 2-fold symmetry and features dithiocarbamate ligands coordinating two octahedral Cd atoms in a μ 2 κ 2 -tridentate mode. Binuclear 2 is centrosymmetric with two ligands being μ 2 κ 2 -tridentate as for 1 but the other two being κ 2 -chelating leading to square pyramidal geometries. The conversion of the kinetic crystallization product, 1, to thermodynamic 2 is irreversible but transformations mediated by recrystallization (ethanol and acetonitrile) to related literature SI species, namely coordination polymer [{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 3 .MeCN] ∞ and binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 .2H 2 O.2MeCN, are demonstrated, some of which are reversible. Three other crystallization outcomes are described whereby crystal structures were obtained for the 1:2 co-crystal {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 :2[3-(propan-2-yl)-1,3-oxazolidine-2-thione] (3), the salt co-crystal [iPrNH 2 (CH 2 CH 2 OH)] 4 [SO 4 ] 2 {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 (4) and the salt [iPrNH 2 (CH 2 CH 2 OH)]{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 3 } (5). These arise as a result of decomposition/oxidation of the dithiocarbamate ligands. In each of 3 and 4 the binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 SI, as in 2, is observed strongly suggesting a thermodynamic preference for this form.