S-scheme ZnO/WO 3 heterojunction photocatalyst for efficient H 2 O 2 production

Designing highly efficient photocatalyst for hydrogen peroxide (H 2 O 2 ) production is an ideal strategy to avoid the shortcomings of traditional H 2 O 2 production and to realize the conversion of solar energy to chemical energy. In this work, a step-scheme (S-scheme) heterojunction photocatalyst composed of ZnO and WO 3 is carefully prepared by hydrothermal and calcination method for efficient photocatalytic H 2 O 2 production. The ZW30 composite photocatalysts exhibit enhanced activity with the highest H 2 O 2 production rate of 6788 mu mol L -1 h -1 . The results show that the photocatalytic H 2 O 2 production process is dominated by a direct two-electron O 2 reduction pathway. The enhanced photocatalytic H 2 O 2 production activity is attributed to the formation of interfacial internal electric field (IEF) in the S-scheme heterojunction, which boosts the spatial separation of charge carriers and enables electrons with the strongest reduction power to participate in H 2 O 2 production. This work provides an in-depth insight of the great advantages of S-scheme heterojunction in photocatalytic H 2 O 2 production. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.