High-Efficiency Photocatalytic Hydrogen Peroxide Production on BiOCl/BiOBr Heterojunction

Photocatalytic hydrogen peroxide production is considered an important technology for alleviating environmental problems and energy scarcity at present. In this work, a series of BiOCl/BiOBr Z-type heterojunctions were successfully synthesized by a facile one-step method. The successful formation of the heterostructure was confirmed through techniques such as XRD, SEM, HRTEM, FTIR, and XPS. Notably, the heterojunction exhibited significantly enhanced photocatalytic performance in hydrogen peroxide production. The best performing sample (BiOCl/BiOBr 2:8) showed the highest hydrogen peroxide concentration of 10.8 mmol/L. PL and EIS results demonstrated the crucial role of the heterojunction in promoting charge transfer and separation during the photocatalytic process, and retaining the strong redox ability of electrons/holes on different active sites. The free radical trapping experiments results and electron spin resonance spectra demonstrated that photocatalytic pathway of the as-prepared heterojunctions was in the dual-channel route, from both oxygen reduction and water oxidation. This work might provide a reliable strategy for photocatalytic hydrogen peroxide production via photocatalysis.