Abstract: Recently, S-scheme heterojunctions have gained considerable attention in the field of photocatalytic environmental remediation as their potential to achieve efficient spatial charge separation coupled with strong redox capacities. Herein, this review provides an overview of the current state-of-the-art in the development of S-scheme-based photocatalysts for the purification of environmental contaminants. The review first covers the fundamentals of heterogeneous photocatalysis for environmental purification. Subsequently, an introduction to the background, mechanism, design principles, and characterization techniques of S-scheme heterojunctions is presented. Then, the review presents a comparison and summary of using various S-scheme photocatalysts for the removal of several target pollutants, such as bacteria, heavy metals, nitrogen oxides, antibiotics, and phenols. Additionally, the modification strategies of S-scheme heterojunction photocatalysts are also provided. Finally, a brief discussion of the challenges and prospects associated with S-scheme photocatalytic systems is demonstrated.

Key words: S-scheme heterojunctions, Photocatalyst, Pollutant, Environmental remediation