Combined method for obtaining ultradispersed powders of vanadium oxides and carbide

Abstract

New opportunity to synthesize nano- and ultradispersed powdered materials by combining of two procedures, classical liquid-phase precipitation and low-temperature microwave calcination, at a rather simple instrumentation is described. It was found in precipitation of precursors that, depending on the synthesis conditions (solution pH, amount of carbon, synthesis on the vessel surface or in the solution bulk), particles of hydrated vanadium oxide have different morphologies. It was also found that precursor powders have an insignificant microporosity, which is preserved in the final products in trace amounts upon thermal treatment of samples. Intermediate and final vanadium products were synthesized in an electromagnetic field in a flow of argon, their phase composition and structure were examined in the stages of thermolysis, reduction, and carbidization, and their lattice constants were calculated. The morphology, size, and particle size distribution in the samples under study were determined.