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123.
T. D. Dzhafarov S. S. Yesilkaya N. Yilmaz Canli M. Caliskan 《Solar Energy Materials & Solar Cells》2005,85(3):371-383
The effective diffusion coefficients of Cu for thermal and photodiffusion in the CdTe films have been estimated from resistivity versus duration of thermal or photoannealing curves. In the temperature range 60–200°C the effective coefficient of thermal diffusion (Dt) and photodiffusion (Dph) are described as Dt=7.3×10−7exp(−0.33/kT) and Dph=4.7×10−8exp(−0.20/kT).It is found that the diffusion doping of CdTe thin films by Cu at 400°C results in a sharp decrease of resistivity up to 7 orders of magnitude of p-type material, depending on thickness of Cu film. The comparative study of performance of CdTe(Cu)/CdS and CdTe/CdS cells has been studied. It is shown that the diffusion doping of CdTe film by Cu increases efficiency of CdTe(Cu)/CdS cells from 0.9% to 6.8%. The degradation of photovoltaic parameters of CdTe(Cu)/CdS cell, during testing under forward and reverse bias at room temperature, proceeds at a larger rate than those of CdTe/CdS cell without Cu. The degradation of performance of CdTe(Cu)/CdS cells is tentatively assigned to electrodiffusion of Cu in CdTe, resulting in redistribution of concentration of Cu-related centers in CdTe film and heterojunction region. 相似文献
124.
分析了钼精矿Cu、Pb含量高的主要原因 ,通过实施一系列措施 ,达到了降低钼精矿中Cu、Pb含量的目的 相似文献
125.
Benedetto Bozzini Bertrand Busson Claudio Mele Abderrahmane Tadjeddine 《Journal of Applied Electrochemistry》2008,38(7):897-906
We report on potential-dependent in situ SFG and DFG spectroscopy carried out at Au(111), Au(210), polycrystalline Au, Au–Cu
and Au–Ag–Cu electrodes in contact with aqueous solutions containing CN− and 4-cyanopyridine (4CP). Spectroelectrochemical work was complemented by cyclic voltammetry. The chief stress has been
placed on systematising and quantifying the interaction between 4CP and CN− and the attending effects on the vibrational and electronic structures of the interface. The voltammetric behaviour of the
investigated electrodes, modified by the addition of 4CP to the CN− electrolyte, denote changes in the CN− adsorption characteristics and effects of the adsorbed CN− layer on the electrodic reactivity of 4CP. The differences among the investigated electrodes can be explained in terms of
their respective degrees of atomic packing or with alloying effects on the stability of adsorbed CN−. The potential-dependent spectra have been analysed quantitatively with a model for the second order non linear susceptibility
accounting for vibrational and electronic effects. The spectral changes induced by addition of 4CP denote interaction of the
aromatic with the electrode through the CN− monolayer. The non-resonant contribution yields information on the effects of 4CP on the fine structure of the bound electron
density of states. 相似文献
126.
Using nickel-2,2′-dipyridyl complex as a template, N-vinyl-2-pyrrolidone as the metal coordination functional monomer, and ethylene glycol dimethacrylate as the crosslinker, polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membrane as the supported membrane, metal complex imprinted polymeric membranes were prepared. The association constant of template-monomer interaction in the prepolymerization solution was estimated to be 4.38 × 104 (L/mol)2 by spectrophotometric titration analysis. The attenuated total reflection Fourier transform infrared spectroscopy and scanning electron micrograph characterization indicated that the surface of the support PVDF membrane was completely coated by the imprinted polymer layer after modification. The imprinted membranes exhibited the selective permeability for the template in certain nickel acetate solution. The molecularly imprinted membranes gave higher permeation separation factors at about pH 6, whereas increasing pressure would lower the separation ability. The effects of ion concentration, cations and counterions, ligand selectivity, pH, and trans-membrane pressure were investigated and the permeation performances of the imprinted membranes could be regarded as facilitated transport mechanism. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
127.
Poly(3-n-octyloxythiophene), a conjugated polymer, which possessed solubility in common organic solvents, was synthesized by electrochemical polymerization in the presence of lithium perchlorate as the supporting electrolyte and sodium dodecyl sulfate as the surfactant in an aqueous medium. Characterizations of the intermediate, monomer, and polymer were performed by NMR spectroscopy, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, and gel permeation chromatography. The process of electrochemical polymerization and the electrochemical redox behaviors were investigated by cyclic voltammetry and the potentiostatic method. A poly(3-n-octyloxythiophene) film that was deposited on a platinum electrode was found to exhibit electrochromic behaviors, and it switched electrochemically between blue–green oxidized and dark red reduced states. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
128.
Gerda C. Glaeser 《Thin solid films》2007,515(15):5964-5967
Fluorescent photon down conversion for the improvement of the blue response of ZnO/CdS/Cu(In,Ga)Se2 heterojunction solar cells and modules is investigated. Fluorescent dyes of the series Lumogen® F are analyzed by optical transmission and reflection as well as by photoluminescence measurements. A spectral transfer matrix formalism is introduced that allows to predict the suitability of a luminescent dye as a down-converter for a given solar cell from its absorption/emission properties. We find that Lumogen® F Violet 570 and Lumogen® F Yellow 083 as well as a combination of both yields improvements for Cu(In,Ga)Se2 solar modules. Particularly, we find that the short circuit current density of a Cu(In,Ga)Se2 mini-module is improved by 1.5 mA cm− 2 when applying a varnish with a combination of Lumogen® F Violet and Yellow. About 0.5 mA cm− 2 of this improvement is due to a reduced overall reflectance and an improvement of 1 mA cm− 2 results from the frequency conversion by the dyes. 相似文献
129.
The reversible persistent changes of the fill factor (FF) induced by the illumination and voltage bias along with changes in the electronic properties of the ZnO/CdS/Cu(In,Ga)Se2 photovoltaic devices have been studied. Admittance spectroscopy and capacitance–voltage characterization reveal a correlation between the FF and the space charge distribution within the absorber. Our experiments provide evidence that a major source of FF loss in efficient devices is caused by excess negative charge close to the interface. We explain the persistent changes in the net acceptor concentration in the interface region by the relaxation effects due to compensating donors—the same mechanism, which leads to metastable changes of the doping level in the bulk of the absorber. 相似文献
130.
La改性的Ag/TS-1催化剂上丙烯选择氧化制环氧丙烷 总被引:1,自引:0,他引:1
在H2 和O2 混合气体存在下 ,在常压固定床、石英反应器上考察了La改性的Ag/TS - 1催化剂催化丙烯环氧化反应。研究结果表明 ,Ag和La负载在TS - 1上的先后顺序对丙烯环氧化反应有影响。H2 在丙烯气相氧化反应体系中起着重要的作用。 相似文献