S-Scheme Heterojunction Photocatalysts for H₂O₂ Production

Photocatalysis opens a new door to H₂O₂ formation via a low-cost, clean, mild, and sustainable process, which holds great promise for the next generation of massive H₂O₂ production. However, fast photogenerated electron-hole recombination and slow reaction kinetics are the main obstacles for its practical application. An effective solution is to construct the step-scheme (S-scheme) heterojunction, which remarkably promotes carrier separation and boosts the redox power for efficient photocatalytic H₂O₂ production. Considering the superiority of S-scheme heterojunctions, this Perspective summarizes the recent advances of S-scheme photocatalysts for H₂O₂ production, including photocatalysts for building S-scheme heterojunctions, H₂O₂-production performance, and S-scheme photocatalytic mechanisms. Lastly, some prospects are given to motivate future research in this promising field, other promising strategies are provided to further improve H₂O₂ yields, and future research directions are suggested.