Construction of a Bioinspired Hierarchical BiVO₄/BiOCl Heterojunction and Its Enhanced Photocatalytic Activity for Phenol Degradation

Development of a p–n heterojunction to achieve efficient degradation of organic pollutants is a promising approach in the field of photocatalysis. Herein, BiVO4 with bioinspired hierarchical structures was prepared with the sol–gel method and combined with BiOCl nanoplates to construct a 3D/2D configuration via an in situ deposition route. The hierarchical BiVO4 served as an excellent substrate to achieve the uniform loading of BiOCl nanoplates. The obtained 3D/2D BiVO4/BiOCl hybrids exhibited significantly enhanced photocatalytic efficiency for degrading phenol under visible light irradiation, with a first-order reaction rate constant that was 9.9 and 1.9 times higher than those of hierarchical BiVO4 and the BiVO4/BiOCl hybrids without hierarchical structures, respectively. Moreover, the hierarchical BiVO4/BiOCl also displayed good photochemical stability for the degradation of phenol after three recycles. The p–n heterojunction and hierarchical structure worked together to form a spatial conductive network framework, which possessed improved visible light absorption, high specific surface area, as well as effective separation and transfer of photogenerated charge carriers.