Heterojunction for Boosting Photo‐Oxidation of Organic Contaminants

ABSTRACT The unrelenting existence of organic contaminants (OC) in water systems poses a severe threat to the environment and human health. Therefore, there is a need to develop sustainable and efficient water treatment technologies. In this aspect, semiconductor (SC)‐based photocatalyst (PC) has emerged as a next‐generation material for the photo‐degradation of OC. However, its practical application is often limited by low quantum efficiency, rapid recombination rate, and lower visible‐light utilization. In this context, creating heterojunctions has gained significant attention from researchers to enhance photocatalytic performance by improving charge separation and the adsorption of photons. This article summarizes the recent advances in numerous heterojunction systems such as type‐I, type‐II, Z‐scheme, S‐scheme, Schottky, and p‐n junctions, with a focus on their design, structural‐activity, and interfacial charge transfer mechanisms. With emphasis on the role of band alignment and surface reactive species that boost the photo‐oxidation of OC. Additionally, the design of heterojunctions, photocatalytic reaction pathways, and factors influencing degradation efficiency are discussed. Finally, the current challenges and future perspectives for the rational design of next‐generation heterojunction PC for the photo‐degradation of OC are highlighted. Therefore, this article offers newer insights for the development of highly efficient and scalable heterojunction‐based photocatalytic systems for OC.