Faced with the growing consumption of fossil fuels and the consequent energy/ecological crisis, photocatalysis has become a realistic option to develop new energy source and realize the carbon neutrality. Heterojunction photocatalysts constructed by multiple semiconductors with staggered band structure can spatially separate redox reaction sites to realize synergistic oxidation and reduction reactions, and have captured broad interest. However, the undesigned heterojunctions still encounter some headache difficulties, that is the poor interfacial contact, which will block carrier mobility, thus result in inefficient and instable catalysts. Recently, researchers have been focusing on constructing chemical bonds (especially covalent bonding) between different semiconductors to induce the formation of intimate and stable interface contact. Herein, this review article presents the state-of-the-art progress on interfacial chemical bonds (ICB) in heterojunction photocatalysts and clarifies the function mechanism for enhancing photocatalysis. Given that the formation of ICB strongly depends on the surface characteristics of semiconductors, we clarify the formation mechanism and put forward rational design strategies. More importantly, the current photocatalytic applications of ICB are reviewed to have a deep understanding of structure—activity related mechanisms. Finally, our brief outlooks on the current challenges and future development trends of ICB for next-generation photocatalysts are pointed out to create brand-new strategies for optimizing photocatalytic properties and accelerate the practical applications of ICB with high-performance.

面对日益增长的化石燃料消耗和随之而来的能源/生态危机，光催化已成为开发新能源、实现碳中和的现实选择。由交错带结构的多个半导体构成的异质结光催化剂可以在空间上分离氧化还原反应位点，实现协同氧化和还原反应，引起了广泛关注。然而，未经设计的异质结仍会遇到一些令人头疼的难题，即界面接触不良，这会阻碍载流子的迁移，从而导致催化剂效率低下且不稳定。最近，研究人员一直专注于在不同半导体之间构建化学键（尤其是共价键），以诱导形成紧密而稳定的界面接触。在此处，这篇综述文章介绍了异质结光催化剂中界面化学键 (ICB) 的最新进展，并阐明了增强光催化的作用机制。鉴于ICB的形成很大程度上取决于半导体的表面特性，我们阐明了形成机制并提出了合理的设计策略。更重要的是，回顾了 ICB 的当前光催化应用，以深入了解结构-活性相关机制。最后，我们对下一代光催化剂ICB当前面临的挑战和未来发展趋势进行了简要展望，以制定优化光催化性能的全新策略，加速ICB的高性能实际应用。