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A. Khare 《辐射效应与固体损伤》2013,168(11):631-644
The effect of KI/LiF/CdCl2 on photoluminescent and electroluminescent (EL) spectra have been reported for (Zn-Cd)S:Cu films. Nanocrystalline films of (Zn-Cd)S:Cu have been prepared using chemical deposition technique in aqueous alkaline bath and their subsequent condensation on substrates. Important results in terms of XRD, SEM, absorption spectra, PL and EL spectra, voltage and frequency dependence of EL brightness are presented. Also, EL brightness waves, EL decay and dependence of EL brightness on nature of electrode material are presented and discussed. SEM studies show best growth conditions in the presence of CdCl2. Results of XRD studies are associated to ZnS and CdS. Both the studies show average particle sizes to be in the nano order. PL and EL emissions from different films show emission peaks in the blue–green region. Results of absorption spectra show a slight change in band gaps owing to the addition of impurities. Voltage dependence of EL brightness shows effectiveness of acceleration–collision mechanism. Frequency dependence of EL brightness first shows an increase in brightness in the lower frequency range, followed by saturation at higher frequencies. Brightness waves consist of primary and secondary waves, which depend on voltage and frequency of excitation. EL cells with Al electrode give better brightness compared with cells with Ag electrodes. The lifetimes of EL emission are found to be of the order of microseconds. 相似文献
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Shyang Roeng Sheen Ching Haai Kao Maw-Kuen Wu Dian Hau Chen Ju-Chun Huang Chien Hong Cheng Chau Ting Chang 《中国化学会会志》1995,42(3):529-532
Thick films of YBa2Cu4O8 superconductor were prepared by a spray-pyrolysis coating technique using silver strip as the substrate. The precursor solution consisted of metal nitrates dissolved in a mixture of ethandiol and water. The solution was nebulized onto the heated substrates to obtain films as-deposited. The temperature of deposition had a great effect on the morphology of the film. Sintering the films in flowing oxygen at 810 °C for 60 h yielded films with Tc(onset) = 82.0 K and Tc(zero) = 74.6 K. Films were characterized by x-ray diffraction, scanning electron microscopy, transport and magnetic measurements. 相似文献
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A. Abrutis A. Teiserskis G. Garcia V. Kubilius Z. Saltyte Z. Salciunas V. Faucheux A. Figueras S. Rushworth 《Journal of membrane science》2004,240(1-2):113-122
Dense ceramic mixed ionic and electronic conducting membranes have been deposited by atmospheric spray-pyrolysis technique onto porous ceramic substrates. Perovskite oxide layers, i.e. manganites La1−xSrxMnO3, ferrites La1−xSrxFe1−y(Co,Ni)yO3, gallates La1−xSrxGa1−y(Co,Ni,Fe)yO3, cobaltites La1−xSrxCoO3 and related perovskites such as lanthanum nickelate La2NiO4 layers have been prepared. The structure, morphology and composition of the layers were characterised by XRD, SEM and WDS, respectively. Density and gas tightness of the layers were studied as a function of deposition process parameters, film thickness (from 0.5 to 3 μm) and preparation procedure. The presence of cracks and defects due to thermo-mechanical stresses applied during or after the preparation process were correlated with the membrane composition and the corresponding thermal expansion coefficient differences between substrates and membranes. 相似文献
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