Structural phase transition of VO2(B) to VO2(A)

Abstract

The phase transition in metastable phases of vanadium dioxide, from VO₂(B) to VO₂(A), has been investigated. The transition to VO₂(A) was induced mechanochemically by compressing or grinding VO₂(B) powders and subsequent heat treatment. In non-stressed samples, the transition proceeded slowly with prolonged heat treatment. Because of the structural relationship between the two phases, the transition is considered to be caused by the shift of oxygen vacancies in the f.c.c. lattice. According to the energy calculation, the two phases have almost the same lattice energies.