Construction of a 1D/2D S-Scheme Heterojunction of Mo-Doped WO<sub>3</sub>/In-Doped Carbon Nitride for Efficient Hydrogen Peroxide Photosynthesis
Ran Zhang, Jiaming Wu, Keyan Li, Sufeng An, Chunshan Song, Xinwen Guo
Abstract
Polymeric carbon nitride (CN) is a promising photocatalyst in H 2 O 2 photosynthesis due to its low cost and high 2e – oxygen reduction reaction (ORR) selectivity. However, the H 2 O 2 yield is still unsatisfactory due to its limited light absorption and high carrier recombination rate. Herein, an S-scheme heterojunction consisting of Mo-doped WO 3 nanowires and In-doped CN nanosheets (Mo-WO 3 /In-CN) was constructed. The heterojunction exhibits a remarkably enhanced photocatalytic performance with a H 2 O 2 production rate of 3082.9 μmol g –1 h –1, which is 33.4 and 8.6 times those of Mo-WO 3 and In-CN, respectively. Moreover, the H 2 O 2 production rate still reaches 462.3 μmol g –1 h –1 in pure water. Mechanism studies demonstrate that H 2 O 2 is produced through dual routes of ORR and water oxidation reaction. The construction of the S-scheme heterojunction enhances the absorption of visible light and improves the separation efficiency and redox ability of the photogenerated carriers. Meanwhile, increased surface area and good hydrophilicity of the heterojunction also contribute to the improved H 2 O 2 yield. This work provides insight into the design of high-efficiency photocatalysts for H 2 O 2 synthesis.