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101.
102.
Fabrication of high performance thin films from metal fluorocomplex aqueous solution by the liquid phase deposition 总被引:1,自引:0,他引:1
Hnin Yu Yu Ko Minoru Mizuhata Akihiko Kajinami Shigehito Deki 《Journal of fluorine chemistry》2003,120(2):157-163
The hetro-structured oxide thin films from metal fluorocomplex solution have been prepared by the liquid phase deposition (LPD) method. The Pt/Nb2O5 and Au/Nb2O5 composite films can be prepared from a mixed solution of niobium source, H3BO3, Pt(NH3)4Cl2 and HAuCl4 aqueous solutions under the ambient temperature and atmosphere. In the case of Au/SiO2 composite film, (NH4)2SiF6 solution is used as a mother solution. The Pt and Au ionic species are deposited in Nb2O5 and SiO2 matrices. They are reduced to their metallic state after treatment above 200 °C. The size of dispersed particles can be controlled by heat treatment temperature. It is also clear that, gold nanoparticles are also found to interact with SiO2, although the interaction is smaller than that with Nb2O5 showing the size of Au nanoparticles remain smaller in Nb2O5 that in SiO2. 相似文献
103.
Kiyoshi Ozawa Yoshio Sakka Muneyuki Amano 《Journal of Sol-Gel Science and Technology》2000,19(1-3):595-598
Cubic antimonic acid (Sb2O5·nH2O) films were successfully prepared on stainless steel and Si(100) substrates by electrophoretic deposition (EPD) using two types of sols. The sols were prepared by reacting an H2O2 aqueous solution with Sb(O-i-C3H7)3 or metallic Sb powder. The resulting films were found to consist of fine particles of cubic Sb2O5·nH2O single crystals with uniform particle sizes of 30 nm and 150 nm. The weight of the Sb2O5·nH2O deposit on the anode Si(100) substrate by EPD increased linearly with the current density in the range of 0–0.67 mA cm–2, when the sol pH was over 7. The proton conductivity of the polycrystalline Sb2O5·nH2O discs, formed from the two types of sols, was evaluated by an ac impedance method at room temperature under controlled levels of relative humidity. 相似文献
104.
N. G. Komissarova N. G. Belenkova L. V. Spirikhin O. V. Shitikova M. S. Yunusov 《Chemistry of Natural Compounds》2002,38(1):58-61
Oxidation of betulin by pyridinium dichromate, pyridinium chlorochromate, and K2Cr2O7 -H2SO4 in the presence of tetrabutylammonium bromide was studied. Products of regioselective C-3, C-28-, and exhaustive oxidation, 28-hydroxylup-20(29)-3-one, 3-hydroxy- and 3-oxolup-20(29)-en-28-al were obtained. 相似文献
105.
106.
先在0.5 mol·L-1硝酸介质中活化氟离子选择性电极,再在含硝酸的总离子强度调节混合液(TISAM)中测定氟,线性范围为1×10-7~1×10-2mol·L-1,检出限为1.9μg·L-1。该方法应用于绿茶饮料、水、牛奶中痕量氟的测定,结果的RSD小于4.8%,回收率在96.1%至100.2%之间,对氟离子选择性电极在硝酸介质中的活化机理作了阐述。 相似文献
107.
An extract of crystal violet-tetrachloroferrate(III) in nitrobenzene was used to prepare a tetrachloroferrate(III)-selective liquid membrane electrode with a poly(vinyl chloride) support. The optimal conditions to determine 2.5 × 10–5 – 5.0 × 10–2
M iron(III) as tetrachloroferrate(III) (anionic slope 56 mV/decade, detection limit 7.9 × 10–6
M) were found to be 4.0–5.5.M total chloride in 0.75–1.5M hydrochloric acid. The electrode was reliably applied to determine iron in human blood, haematite and mineralized vitamin syrup by direct potentiometry, standard and sample additions as well as standard subtraction techniques. 相似文献
108.
Modern condensed-matter physics is increasingly concerned with the design, synthesis, analysis, and exploitation of chemically complex materials and structures. Complex metal oxides and strongly correlated electron systems such as YBa2Cu3O7−x and La1−xSrxMnO3 are paradigmatic examples. Their production in the form of high-quality thin films is of both technological and fundamental importance and has stimulated a concerted effort in the last two decades to find and optimize efficient techniques to this end. This review discusses the physics behind and the requirements for synthesizing high-quality films of such materials and examines fundamental aspects of the growth processes associated with magnetron sputtering and pulsed laser deposition, the two techniques which presently offer the best solutions in this burgeoning field. 相似文献
109.
Kihyun Cho Jangwon Oh Taewon Lee Dongwook Shin 《Journal of Analytical and Applied Pyrolysis》2007,80(2):502-506
Aerosol flame pyrolysis deposition method was applied to deposit the oxide glass electrolyte film and LiCoO2 cathode for thin film type Li-ion secondary battery. The thicknesses of as-deposited porous LiCoO2 and Li2O–B2O3–P2O5 electrolyte film were about 6 μm and 15 μm, respectively. The deposited LiCoO2 was sintered for 2 min at 700 °C to make partially densified cathode layer, and the deposited Li2O–P2O5–B2O3 glass film completely densified by the sintering at 700 °C for 1 h. After solid state sintering process the thicknesses were reduced to approximately 4 μm and 6 μm, respectively. The cathode and electrolyte layers were deposited by continuous deposition process and integrated into a layer by co-sintering. It was demonstrated that Aerosol flame deposition is one of the good candidates for the fabrication of thin film battery. 相似文献
110.
基于普通的能斯特方程, 建立了单原子层平衡电势的热力学模型. 据此, 分析了单原子层覆盖度以及电吸附价与欠电势之间的相互关系, 获得了沉积物与衬底之间干涉特性. 并且分析了Bi-Te基体系欠电势沉积热力学特性. 通过对Bi欠电势沉积在几个不同的金属衬底体系的分析阐明了功函数随覆盖度的变化机制. 研究了铋离子的浓度变化对铋的欠电势及覆盖度的影响关系, 结果表明, 铋在铂上欠电势沉积的体系在整个欠电势范围内具有恒定的电吸附价, 而铋在覆盖了一层碲的铂衬底上欠电势沉积的体系其电吸附价随覆盖度的增加而降低, 从热力学理论角度对铋在碲覆盖的衬底上导致欠电势负移的特性给予了解释. 相似文献