Metal-free catalysts for hydrogen peroxide production with electrocatalysis and photocatalysis

Abstract

Hydrogen peroxide (H₂O₂) is a widely used oxidant while energy consumption and environmental concerns are challengeable issues faced during its traditional production. The production of H₂O₂ by electrocatalysis or photocatalysis is considered as economical and environmentally friendly approach while metal-free electrocatalysts and photocatalysts were intensively investigated in recent years. In this paper, we reviewed the progress of the applications of metal-free catalysts in electrocatalysis and photocatalysis for H₂O₂ production, mainly focusing on catalyst design and preparation, characterization techniques employed, and reaction mechanism proposed. The shortcomings and limitations of metal-free catalysts were further discussed while the possible solutions were provided. The review would help the community to develop efficient, stable, and economical metal-free catalysts for the electrocatalytic and photocatalytic production of H₂O₂.