Defect‐driven innovations in photocatalysts: Pathways to enhanced photocatalytic applications

Defect engineering in photocatalytic materials has garnered significant interest due to the considerable impact of defects on light absorption, charge separation, and surface reaction dynamics. However, a limited understanding of how these defects influence photocatalytic properties remains a persistent challenge. This review comprehensively analyzes the vital role of defect engineering for enhancing the photocatalytic performance, highlighting its significant influence on material properties and efficiency. It systematically classifies defect types, including vacancy defects (oxygen and metal vacancies), doping defects (anion and cation), interstitial defects, surface defects (step edges, terraces, kinks, and disordered layers), antisite defects, and interfacial defects in the core–shell structures and heterostructure borders. The impact of complex defect groups and manifold defects on improved photocatalytic performance is also examined. The review emphasizes the principal benefits of defect engineering, including the enhancement of light adsorption, reduction of band gaps, improved charge separation and movements, and suppression of charge recombination. These enhancements lead to a boost in catalytic active sites, optimization of electronic structures, tailored band alignments, and the development of mid‐gap states, leading to improved structural stability, photocorrosion resistance, and better reaction selectivity. Furthermore, the most recent improvements, such as oxygen vacancies, nitrogen and sulfur doping, surface defect engineering, and innovations in heterostructures, defect‐rich metal–organic frameworks, and defective nanostructures, are examined comprehensively. This study offers essential insights into modern techniques and approaches in defect engineering, highlighting its significance in addressing challenges in photocatalytic materials and promoting the advancement of effective and adaptable platforms for renewable energy and environmental uses. image