In-situ grown N, S co-doped graphene on TiO2 fiber for artificial photosynthesis of H2O2 and mechanism study

Artificial photosynthesis offers a promising strategy for converting solar energy into environmental-friendly H2O2. Herein, robust photocatalytic H2O2 production through dioxygen reduction is achieved, reaching a high H2O2 yield of 873 μmol L−1 h−1. The photocatalyst was prepared by in-situ chemical vapor deposition of N, S co-doped graphene on TiO2 nanofibers. Thanks to the intimate interface with large area and Schottky junction, the H2O2 yield of the composite can be increased by eight times than that of pristine TiO2. Experimental results and density functional theory calculations clarify that the strong synergistic effect between the doped N and S atoms provides abundant active sites to facilitate the electron transfer, promote the adsorption of O2 molecules, and restrain the decomposition of formed H2O2 by suppressing H2O2 adsorption. This work not only provides a novel approach to build close contact between photocatalyst and co-catalyst, but also develops a highly efficient photocatalyst for H2O2 production.