Synthesis and Characterization of Vanadium Substituted Potassium Tungsten Bronzes, K x V y W 1-y O 3

Abstract

A series of vanadium substituted potassium hexagonal tungsten bronzes KxVyW1-yO3 (K-HTB) were prepared by conventional solid state method at 800 °C with compositions of x = 0.30 and 0.00 ? y ? 0.15. A mixture of K-HTB and non bronze phases with y ? 0.20 was observed. The proportion of this non bronze phase increases with increasing vanadium content. The non bronze phases in the mixture could not be indexed yet. In contrast, a very small amount of vanadium can be substituted in potassium tetragonal tungsten bronzes (K-TTB) at 800 °C with x = 0.50 and 0.00 ? y ? 0.02, however at 700 °C vanadium substituted K-TTB can be prepared with 0.00 ? y ? 0.05. Further substitution of vanadium in K-TTB decomposes to K-HTB and non-bronze phases.