Synthesis of VIB Group Metals Silicides Dispersed Powders by Electrolysis of Halide-Oxide Melts

作     者：Liliia Molotovska Dmytro Shakhnin Natalia Uskova Ganna Nikulina Vladymyr Cherednik Serge Stukota Viktor Malyshev 

作者机构：Department of Physical Chemistry of lonic Liquids V. I. Vernadsky Institute of General and Inorganic Chemistry National Academy of Sciences of Ukraine 32/34 Palladina Ave. Kyiv 03142 Ukraine Faculty of Engineering & Technology University of Ukraine 23 L vivska St. Kyiv 03115 Ukraine 

出 版 物：《Journal of Chemistry and Chemical Engineering》 (化学与化工（英文版）)

年 卷 期：2016年第10卷第1期

页      面：7-12页

学科分类：080903[工学-微电子学与固体电子学] 081702[工学-化学工艺] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0817[工学-化学工程与技术] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

主　　题：金属硅化物 氧化物电解 合成条件 粉末 融化 阴极电流密度 电沉积过程 分散 

摘      要：Study of electrochemical behavior of chromium (molybdenum, tungsten) and silicon containing melts allowed defining conditions for synthesis of silicides of chromium, molybdenum and tungsten in the form of fine powders by electrolysis of halide-oxide melts. Sequence of stages of electrosynthesis of silicides of molybdenum and tungsten was found as follows: deposition of more electropositive metal (molybdenum or tungsten), deposition of the second component (silicon) on the surface of metal deposited previously, and reaction diffusion of silicon into the deep of the metal-salt pear with the formation of silicide phases of different compositions up to the higher silicides. In contrast, during the electrodeposition of chromium silicides, one of the components (chromium) is deposited not in elemental form, but in oxide form, and the other (silicon) acts as a reducing agent for this oxide to form binary compounds. Duration of the synthesis first stage (deposition of refractory metal or of its oxide) depends on the refractory metal compound content in the system and on the cathode current density. Synthesis of silicides is possible due to retention of powders of molybdenum (tungsten) or chromium oxide at the cathode without scaling. Optimal values of concentrations ratio, current density, temperature, and duration of electrosynthesis were found. Phase composition of products were obtained, as well as their chemical and thermal stability, were studied.