2016-Sustainable Industrial Processing Summit
SIPS 2016 Volume 9: Molten Salts and Ionic Liquids, Energy Production

Editors:	Kongoli F, Gaune-Escard M, Turna T, Mauntz M, Dodds H.L.
Publisher:	Flogen Star OUTREACH
Publication Year:	2016
Pages:	390 pages
ISBN:	978-1-987820-24-9
ISSN:	2291-1227 (Metals and Materials Processing in a Clean Environment Series)

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Synthesis of Disperse Powders of VI-B Group Metals Silicides from Ionic Melts

Viktor Malyshev¹; Alla Sushchenko²; Angelina Gab³; Natalia Uskova¹; Oleksandr Podyman¹; Marcelle Gaune-Escard⁴;
¹IGIC NASU, Kyiv, Ukraine; ²V.I. VERNADSKY INSTITUTE OF GENERAL AND INORGANIC CHEMISTRY OF THE NATIONAL ACADEMY OF SCIENCES OF UKRAINE, Kyiv, Ukraine; ³NATIONAL TECHNICAL UNIVERSITY OF UKRAINE, Kyiv, Ukraine; ⁴AIX-MARSEILLE UNIVERSITé/POLYTECH, CNRS/IUSTI UMR7343, Marseille, France;
Type of Paper: Regular
Id Paper: 204
Topic: 13

Abstract:

The aim of the present work is the realization of high-temperature electrochemical synthesis of VI-B group metals silicides by electrolysis of halide-oxide melts.<br />Methods: cyclic voltammetry, potentio- and galvanostatic electrolysis, X-ray phase analysis.<br />Preliminary experiments on electrolysis of chromium (molybdenum, tungsten) and silicon containing melts make it possible to generalize findings into the following sequence of steps for electrosynthesis of silicides of molybdenum and tungsten: I—deposition of more electropositive metals (molybdenum or tungsten); II—deposition of the second component-silicon-on the surface of Mo or W deposited earlier; III—silicon reaction diffusion into the depth of metal-salt “pear” with formation of silicides phases of different compositions up to higher silicides. <br />Unlike high-temperature electrochemical synthesis of silicides of molybdenum and tungsten, during this synthesis, one of the components are not deposited in elementary form but rather in oxide form, and the other act as a reducing agent of the mentioned oxide to form binary compounds.<br />Thus, during electrolysis of chromium (molybdenum, tungsten) and silicon containing melts, high temperature electrochemical synthesis of powders of silicides of chromium, molybdenum, and tungsten was implemented.<br />Keywords: Chromium, molybdenum, tungsten, silicides, synthesis, dispersed powders, ionic melts.

Keywords:

Molten Salt Chemistry and Thermodynamics;


References:

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Cite this article as:

Malyshev V, Sushchenko A, Gab A, Uskova N, Podyman O, Gaune-Escard M. Synthesis of Disperse Powders of VI-B Group Metals Silicides from Ionic Melts. In: Kongoli F, Gaune-Escard M, Turna T, Mauntz M, Dodds H.L., editors. Sustainable Industrial Processing Summit SIPS 2016 Volume 9: Molten Salts and Ionic Liquids, Energy Production. Volume 9. Montreal(Canada): FLOGEN Star Outreach. 2016. p. 143-150.