Abstract

The Bi-based hierarchical multi-component photocatalytic system is an important player in energy and environmental catalysis due to its full-spectrum light absorption and stable separation of photo-generated charges. In this study, a novel family of iodine doped Bi₂O₂CO₃/Bi₂WO₆ heterojunctions was successfully developed by a facile ionic liquid assisted solvothermal method. A visible light photocatalytic H₂ production rate of 664.5 μmol g−1 h−1 (0.3I-Bi₂O₂CO₃/Bi₂WO₆ with 3% Pt) has been durably obtained, much higher than those of pristine and undoped counterparts. The photocatalysts are also capable for persistent pollutant and dye degradation. Through electrochemical and spectroscopic tests and density functional theory calculation, the enhanced photocatalytic activity is attributed to formation of the Z-scheme photocatalyst. Therein, the lowered and indirect bandgap and heterojunctional band alignment spontaneously benefit visible light harvesting, electron-hole pair separation, and proton reduction. Besides a facile synthesis for effective photocatalysis, the Z-scheme mechanism is hoped to facilitate the design and realization of similar systems for photocatalytic H₂ evolution and organic hazards decontamination.