Multi-Prismatic Hollow Cube CeVO₄ with Adjustable Wall Thickness Directed towards Photocatalytic CO₂ Reduction to CO

Ternary orthovanadate compounds have received increasing attention due to their broad light absorption and diverse crystal structure. However, their multi-assembled crystal morphologies are limited mainly due to their initially polyatomic VO₄ groups. In this study, multi-prismatic hollow cubic CeVO₄ microstructures were fabricated by a one-step solvothermal method without any organic agents. The increase in wall thickness is in accordance with the radial direction of the quadrangular prism. Moreover, the overdose of the V precursor is favorable for the formation of hollow micro-cubic CeVO₄, and the wall thickness changes from 200 to 700 nm. Furthermore, these CeVO₄ microstructures were applied to photocatalytic CO₂ reduction with a maximum CO generation rate of up to 78.12 μmol g⁻¹ h⁻¹ under visible light irradiation, which was several times higher than that of the other samples. This superior photocatalytic activity might be attributed to its good crystallinity and unique exposed interior structure. This study provides guidelines for the multi-assembled structure fabrication of ternary compounds and expands upon the exploration of the spatial structure of multivariate compounds.