Determination of ferroelastic phase transition temperature in BiVO4 by Raman spectroscopy

BiVO4, a well-known photocatalyst and industrial pigment, undergoes a reversible ferroelastic phase transition at about 530 K. In this framework, identifying techniques that can accurately measure the signature of the ferroelastic phase transition would be very useful. We find that the most intense Raman band of BiVO4 ceramics at 829 cm(-1) shows an interesting temperature dependency, as it is non-linear in the investigated range of 298-898 K, while two distinct linear regimes can be distinguished below and above 550 K. The point of the intersection after extrapolating the two linear regions is 530 K, which happens to be the ferroelastic phase transition temperature of BiVO4 from monoclinic to tetragonal phase. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

BiVO4 undergoes a reversible ferroelastic phase transition at around 530K, and the most intense Raman band at 829 cm(-1) shows interesting temperature dependency. By distinguishing different linear regimes and extrapolating, the transition temperature is successfully identified at 530K.