Influence of the parameters of thermal decomposition of ammonium tetravanadate on the processes of phase formation of highly dispersed vanadium oxides.

Abstract

The peculiarities of the thermal decomposition of the highly dispersed vanadium (IV) ammonium tetrabutanate salt, which is a precursor for the production of nanocrystalline vanadium oxides of different degrees of oxidation (V2O5, VO2), are studied. The purpose of experimental studies is to determine the influence of the parameters of thermal decomposition of ammonium tetravanadate on the processes of phase formation of nanocrystalline products of vanadium oxides (V2O5, VO2). Optical microscopy and powder X-ray diffraction investigates the dependence of phase-formation and the size of vanadium dioxide particles on the temperature of thermal degradation. Heat treatment of ammonium tetravanadate in an oxidizing atmosphere at a temperature of 400…500 °C leads to the formation of vanadium pentoxide (V2O5), the inert atmosphere contributes to the formation of vanadium dioxide (VO2) at 850…900 °C. The optimum temperature regimes of tetravanodate ammonium trim have been determined for the production of nanocrystalline vanadium dioxide with the phase transition present therein.

Keywords

• ammonium tetravanadate
• vanadium dioxides
• thermal destruction
• phase formation