47 / 2025-03-04 15:13:57

Structural phase transition in BiVO4 nanosheets under high pressure

high-pressure,phase transition,nanosheets,Bismuth vanadate

Bismuth vanadate (BiVO₄) is a well-known kind of photoanode in photocatalytic engineering. The structural stability and tunability of BiVO₄ are of great interest and importance but has not been well understood, especially under pressure. Here, we studied the structure evolution of a fergusonite type BiVO₄ nanosheets using in situ synchrotron X-ray diffraction (XRD), Raman spectroscopy, ultraviolet–visible absorption spectroscopy (UV-vis) and optical microscopy analysis up to ~41.7 GPa, despite of the previously reported fergusonite to scheelite transition(~5 GPa in this research) and scheelite to a monoclinic structure transition (~15 GPa in this research), a potential second-order phase transition at ~10 GPa in scheelite phase, as well as an amorphization at ~16.7 GPa in high pressure monoclinic phase have been observed for the first time. These results suggest BiVO₄ nanosheets exhibit a more complex phase transition routine than their bulk or nano counterparts under pressure, which could promote the fundamental understanding and also guide applications of orthovanadates.