Preparation and Enhanced Catalytic Performance of a Polyhedral BiVO₄-Nanoparticle-Modified ZnO Flower-like Nanorod...

Organic pollutants pose a significant threat to both the ecological environment and human health. In this study, BiVO₄@ZnO heterojunction composites were synthesized via a two-step hydrothermal method. The incorporation of polyhedral BiVO₄ onto the flower-like structure of ZnO effectively enhanced the photocatalytic performance of the composite. Compared with ZnO flower-like nanorods, the BiVO₄@ZnO heterojunction composite photocatalysts achieved degradation efficiencies of 93.18% (k = 0.09063) and 89.64% (k = 0.007661) for methylene blue (MB) within 30 min under ultraviolet and visible light irradiation, respectively. The photocatalytic activity of the BiVO₄@ZnO composites was also evaluated against various organic dyes, including rhodamine B (RhB), Congo red (CR), methyl orange (MO), and methylene blue (MB). Under ultraviolet light, the catalysts showed particularly high activity toward MB and CR. The enhanced photocatalytic performance can be attributed to two main factors: firstly, the heterojunction facilitates the separation of photogenerated electron-hole pairs, thereby improving photocatalytic efficiency; secondly, the composite exhibits a broadened and enhanced light absorption range. Furthermore, the BiVO₄@ZnO heterojunction composites demonstrate excellent cyclic catalytic stability and structural integrity. This study offers a clean and efficient strategy for the photocatalytic degradation of aqueous organic pollutants.