Construction of Z−Scheme Bi2MoO6/CeVO4 Nanofibers Heterojunctions with Enhanced Visible−Light−Driven Photocatalytic Activity

Rare earth vanadate materials have been gradually applied to the field of photocatalysis as a popular semiconductor in recent years, and constructing a heterojunction emerges as a highly promising strategy for augmenting its photocatalytic performance. In this study, a Z−scheme Bi₂MoO₆/CeVO₄ heterojunction photocatalyst was skillfully fabricated by wrapping Bi₂MoO₆ nanosheets on the surface of CeVO₄ nanofibers. Comprehensive characterizations were meticulously employed to analyze the physicochemical structure and morphology of the as−prepared samples, and EIS and BET analysis unequivocally demonstrated that the optimized Bi₂MoO₆/CeVO₄ photocatalyst exhibited outstanding photoelectric properties and larger specific surface area. Under irradiation, the photocatalytic performance of the obtained Bi₂MoO₆/CeVO₄ photocatalyst for the degradation of tetracycline (TC) and other dyes was more than a multi-fold increase in the degradation rate constant than that of pristine CeVO₄, which was far more than other reported CeVO₄-based materials. Meanwhile, the biotoxicity experiments yielded conclusive facts that the biotoxicity of TC solution treated by the Bi₂MoO₆/CeVO₄ photocatalyst was completely eliminated. Ultimately, capture experiments and Electron Paramagnetic Resonance (EPR) analysis were conducted to elucidate the underlying photocatalytic mechanism. The results unambiguously demonstrated that superoxide radicals (^•O₂⁻) assumed a crucial function in the degradation process. Consequently, a plausible direct Z−scheme charge transfer mechanism was successfully clarified. The present work confirms the great potential application prospects of Bi₂MoO₆/CeVO₄ composites in the field of wastewater treatment.