Current status of research on BiOX-based heterojunction photocatalytic systems: Synthesis methods, photocatalytic applications and prospects

Bismuth-based materials have been widely studied and applied in the environmental and energy fields owing to their suitable energy band gap and unique layer structure, among which BiOX in bismuth-based materials has recently become a popular research topic. To improve the performance of BiOX materials, the design of heterojunctions is an effective way. In this paper, we summarize some synthetic methods of BiOX-based heterojunctions in recent years, focusing on the charge transfer pathways and photocatalytic mechanisms of conventional type II heterojunctions, Z-scheme heterojunctions, p-n heterojunctions and S-scheme heterojunctions. The paper also reviews an overview of BiOX-based heterojunction materials for specific applications in the energy and environmental fields. Finally, the possible factors affecting the photocatalytic performance of BiOX-based heterojunctions are presented and the prospects and challenges for their development are discussed.