Photocatalytic studies of type-II, Z-, and S-scheme heterojunctions

Abstract

Nowadays, industrialization and agriculture advancement have led to increased concentration of pollutants in aqueous environment; thus effective wastewater treatment technologies have been required. In this direction, heterojunction photocatalytic systems have gained widespread application area due to their nontoxicity, low cost, and outstanding optical and chemical properties. These photocatalysts can be constructed via three main mechanisms, mainly type-II, Z-scheme, and S-scheme, which are driven by different charge transfer pathways. In this study, we have dealt with the research progress on the three mechanisms, and relevant heterostructure photocatalysts have been discussed in detail, including fabrication method, characterization, and potential application area. In addition, the strategies related to dual Z-scheme-based photocatalysts have been mentioned, and the relevant activity has been compared to their isolated forms in the degradation of emerging contaminating pharmaceuticals and dyes. The current review enables a comprehensive understanding of the state of art in the research field of main heterojunction photocatalytic systems. © 2024 Elsevier B.V., All rights reserved.