Defect engineering is a widely used strategy for tailoring the band structures and surface-active sites of tungsten trioxides (WO3) nanomaterials, thereby enhancing their photocatalytic performance. In particular, precise control of defect topology is recognized as a pivotal step in constructing surface-active sites, enabling the regulation of surface atomic configurations through the deliberate design of defect types and their terminations. This mini-review elucidates the roles of various surface defect types of WO3 semiconductors in photocatalytic redox reactions, revealing how surface defect topology activates reactants at the atomic level. It aims to provide insightful information on defective photocatalysts to guide the optimization of the electronic structures inside photocatalysts, thereby establishing a computational-experimental framework for next-generation adaptive photocatalyst architectures.
