Metal-free Fenton-like photocatalysts based on covalent organic frameworks

Fenton reaction is one of the most efficient and widely used advanced oxidation processes (AOPs) for remediating the ever-growing water pollution. Metal-free photocatalysts for Fenton-like reactions have gathered enormous interest for their advantages including broad pH operation range and high stability. Herein, we report a metal-free covalent organic framework (COF)-based standalone photocatalyst with superior reactivity for Fenton-like reactions, surpassing well-known metal-free photocatalysts and being comparable to the metal-containing catalysts, as well as the remarkable generality. The outstanding performance can be attributed to large porosity, high density of photoactive triazine moiety, the suitable bandgap that originated from the partly interrupted π-conjugation, efficient charge separation and transfer due to the AA stacking, as well as abundant H2O2 binding sites and reaction centers. This work not only provides an efficient metal-free photocatalyst for Fenton-like reactions, but also paves the way for COFs towards industrial applications, aiming for a greener future.