Recent progress in two-dimensional materials for generation of hydrogen peroxide by two-electron oxygen reduction reaction

Hydrogen peroxide (H2O2) is an important green oxidant with a wide range of applications in wastewater treatment, pulp bleaching and chemical synthesis. In recent years, two-electron oxygen reduction reaction (2e-ORR) is expected to be a greener and safer alternative to the more energy-intensive and also carcinogenic anthraquinone process. Among the various electrocatalysts for 2e-ORR, two-dimensional nanomaterials have special advantages in the electrosynthesis of H2O2 due to their large specific surface area, abundant basal and edge sites, and tunable atomic structure. This review article summarizes the synthesis methods, and the strategies and mechanisms for enhancing 2e-ORR properties of 2D materials. Practical problems and serious challenges faced by 2D nanomaterials in the synthesis and 2e-ORR applications are elaborated. The aim of this review is to provide researchers with an understanding of 2D nanomaterials in electrocatalytic applications and to promote the further development of novel 2D nanoelectrocatalytic materials.