Synthesis and phase transition behavior of w-doped VO2(A) nanorods

Abstract

In this paper, pure and w-doped VO2(A) nanorods were synthesized via the reduction of V2O5 with oxalic acid through hydrothermal treatment and characterized by XRD, SEM and DSC. The study about the influence of w-doping on its phase transition and stability properties was carried out for the first time on the best of our knowledge. The doping of tungsten decreased the phase transition temperature of VO2(A) just as it does in the case of rutile VO2(R). The doping limitation of tungsten for pure VO2(A) was estimated to be about 0.5-0.75 at.%, whereas over doping of tungsten led to the destabilization of VO2(A) phase. Based on the experimental results, the solution reaction process should be such that VO2(B) was first formed at lower temperature or shorter time, and then transformed to VO2(A) or VO2(R) during hydrothermal treatment. Furthermore, inhomogeneous doping of tungsten in VO 2 during the crystallization from the solution was revealed by DSC measurements. © 2010 The Ceramic Society of Japan. All rights reserved.