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1.
2.
We have used the periodic quantum-mechanical method with density functional theory at the B3LYP level in order to study TiO2/Sn doped (1 1 0) surfaces and have investigated the structural, electronic and energy band properties of these oxides. Our calculated relaxation directions for TiO2 is the experimental one and is also in agreement with other theoretical results. We also observe for the doped systems relaxation of lattice positions of the atoms. Modification of Sn, O and Ti charges depend on the planes and positions of the substituted atoms. Doping can modify the Fermi levels, energy gaps as well as the localization and composition of both valence and conduction band main components. Doping can also modify the chemical, electronic and optical properties of these oxides surfaces increasing their suitability for use as gas sensors and optoelectronic devices. 相似文献
3.
p—Si上电沉积Ni—W—P薄膜的结构与热稳定性 总被引:3,自引:0,他引:3
研究了p-Si上恒电流沉积Ni-W-P合金薄膜组成与结构的关系,讨论了镀层的组成、结构随沉积时间的变化.测定了非晶合金的晶体结构随热处理温度的改变以及DTA曲线,结果表明,非晶Ni-W-P合金在晶化过程中形成两个纳米超微晶相,非晶Ni-W-P薄膜的热稳定性远高于通常使用的非晶Ni-P薄膜. 相似文献
4.
JiangBinXIA FuYouLI ShuMingYANG ChunHuiHUANG 《中国化学快报》2004,15(5):619-622
Composite nanoporous electrode SnO2/TiO2 was fabricated for the dye sensitized solar cell (DSSC) with N3 (Cis-Ru). After introducing of TiO2, the open-circuit photovoltage (Voc) was higher than that of the pure SnO2 electrode, while short-circuit photocurrent (Isc) was varied with the ratio of the TiO2. Appropriate content of the TiO2 can be beneficial to the efficiency of the solar cell, and it gives negative impact on the composite electrode when the content of TiO2 is higher. 相似文献
5.
Zhiming Liu Jiming Hao Lixin Fu Tianle Zhu Junhua Li Xiangyu Cui 《Reaction Kinetics and Catalysis Letters》2003,80(1):45-52
SnO2/Al2O3 catalyst prepared by sol-gel method showed higher activity than those prepared by impregnation method, and their activity
was significantly improved by pre-treatment in the reaction gas. The increased activity is closely related to the agglomeration
of SnO2 species and the re-exposure of Al2O3, which was previously covered by dispersed SnO2 species.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
硫酸介质中Ti/SnO2/PbO2析氧阳极的研究 总被引:13,自引:0,他引:13
由于硫酸溶液具有高的电导、一般条件下性质稳定、价格相对低廉等优点,所以电化学合成大多在硫酸溶液中进行.阳极析氧是电化学合成不可避免的阳极过程.但因硫酸的强腐蚀性,以及从阳极析出的氧的强氧化性,使得能满足工业生产的阳极材料很缺乏.自1950年荷兰Hen... 相似文献
7.
Katerina Liberkov Raymonde Touroude 《Journal of molecular catalysis. A, Chemical》2002,180(1-2):221-230
Selective hydrogenation of crotonaldehyde was performed on 5% Pt/SnO2 catalysts, in gaseous phase, at atmospheric pressure, at 353 K. Two types of catalyst were prepared using H2PtCl6 and Pt(NH3)4(NO3)2 as metallic precursors. Their performances were compared as a function of the reduction temperature and both catalysts were characterised by X-ray diffraction after different reduction treatments. Using the ex-chloride catalyst, the selectivity values to the unsaturated alcohol (UOL) resulted into a maximum of 45% while a selectivity as high as 70–77%, in 0–25% conversion range, was achieved by using ex-nitrate catalyst reduced at 443 K. The formation of Pt–Sn alloy on the metal particles of platinum was thought to be necessary to improve the activity and the selectivity on these catalysts. In the contrast, a presence of PtSn2 formed at a reduction temperature higher than 473 K led to a decrease of activity and selectivity. 相似文献
8.
《Electroanalysis》2006,18(15):1479-1484
A nanoparticle thin film modified electrode has been constructed using a glassy carbon electrode (GCE) coated with a nano‐tin oxide/dihexadecylphosphate (nano‐SnO2/DHP). In pH 6.0 phosphate buffer solutions (PBS), lomefloxacin (LMF) appeared as an anodic peak with peak potential of 1.35 V at nano‐SnO2/DHP modified electrode. In comparison with a bare GCE or a nano‐SnO2 modified electrode, the nano‐SnO2/DHP modified electrode exhibited an enhanced effectiveness for the oxidation of LMF. Cyclic voltammetry (CVs) coupled with fluorescence and UV/vis absorbance spectra techniques were used to study the interaction of LMF with Calf thymus DNA (ctDNA) in phosphate buffer solutions (PBS). The interaction of LMF and ctDNA could result in a considerable decrease in the peak currents and positive shift in the peak potential, as well as changes of fluorescence, UV/vis adsorption spectra and gel electrophoresis. All the acquired data showed that the new adduct between LMF and ctDNA was formed. Electrochemistry coupled with spectroscopy techniques could provide a relatively easy way to obtain useful information about the molecular mechanism of LMF‐ctDNA interactions. 相似文献
9.
表面修饰的二氧化锡纳米粒子的制备及微结构表征 总被引:11,自引:0,他引:11
采用胶体化学制得表面包覆有DBS的二氧化锡纳米粒子,并运用一系列手段对其微结构进行了表征。 相似文献
10.
Rayleigh and Hyper-Rayleigh scatterings (HRS) from the nano-particle SnO2 were measured. It is found that as the concentration of the colloidal SnO2 or radiation power increases, the first- and second-order polarizabilities decrease. The radiation power dependencies of the first- and second-order polarizabilities show two domains: in high radiation power domain, the first- and second-order polarizabilities are approximately constant, in low radiation power domain, the first- and second-order polarizabilities increase sharply and become sensitive to the radiation power. The behavior of the concentration dependencies of the first- and second-order polarizabilities of colloidal SnO2 particles is similar to that of the radiation power dependence. A detailed mechanism explaining these phenomena has been discussed. 相似文献