Covalent organic framework based photocatalysts for efficient visible-light driven hydrogen peroxide production

Abstract

Hydrogen peroxide (H₂O₂), as an important environmentally friendly oxidant, has been widely used in bleaching, disinfection, wastewater treatment and chemical synthesis, while the artificial photosynthesis of H₂O₂ from H₂O and O₂ over certain photocatalysts has been considered as a clean and energy-saving approach and has been widely explored in recent years. Covalent organic frameworks (COFs) represent a newly blooming class of crystalline porous materials with periodically ordered structures that possess a set of intriguing features, including diverse structural designability and durability, high porosity and low density, wide light-harvesting ability and semiconducting properties. Benefiting from these particular properties, the blooming developments of COFs in recent years have brought promising impetus for the realization of efficient visible-light driven H₂O₂ production. Thus, a systematic and comprehensive review is timely to provide constructive guidance for the development and rational design of more efficient COF-based photocatalysts. In this review, the up-to-date application of COF-based photocatalysts for H₂O₂ photosynthesis was comprehensively summarized and discussed. Firstly, the general background and fundamental principles of COF-based photocatalysts for photocatalytic H₂O₂ production were briefly introduced, followed by the detailed classification and discussion of the strategies reported thus far for realizing improved photocatalytic performance. In addition, the challenges and prospects of COF-based photocatalysts for visible-light driven H₂O₂ production were addressed.