Study on CeO 2 /BiVO 4 Heterojunction Photocatalytic Reduction of CO 2 for a Low‐Carbon Economy

ABSTRACT This study successfully fabricated a 15% CeO 2 /BiVO 4 heterojunction photocatalyst via an in‐situ hydrothermal method and systematically investigated its photocatalytic CO 2 reduction performance under simulated sunlight irradiation. The crystal structure, morphology, elemental composition, and optoelectronic properties of the catalyst were analyzed using multiple characterization techniques, including x‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), x‐ray photoelectron spectroscopy (XPS), UV‐Vis, and photoluminescence (PL). Results indicate that CeO 2 nanoparticles are uniformly loaded onto the BiVO 4 plate‐like structure surface, forming a tightly contacted heterojunction interface that significantly enhances the separation efficiency of photogenerated carriers. Under simulated sunlight irradiation, the 15% CeO 2 /BiVO 4 composite exhibited optimal photocatalytic activity, achieving a CO production rate of 40.3 µmol·g −1 ·h −1 , which is 2.4 times and 1.8 times higher than that of pure CeO 2 and BiVO 4 , respectively. After five cycles of reuse, the composite material exhibited less than 10% activity decline, demonstrating excellent stability. Band structure analysis and Z‐type heterojunction mechanism analysis suggest that the built‐in electric field formed between CeO 2 and BiVO 4 effectively promotes the separation and transfer of photo‐generated electrons and holes, thereby enhancing the photocatalytic CO 2 reduction efficiency.