Three‐Dimensional Covalent Thiazolo[5,4‐d]thiazole Frameworks with sur‐a Topology for Coupling Photoactivation of Oxygen and Biomass

Abstract

Abstract Developing new topological three‐dimensional (3D) covalent organic framework (COF) structures with strong electron donor–acceptor (D–A) properties represents a promising approach for harvesting high‐performance photocatalysts. In this study, we developed two unprecedented 3D COFs with sur‐a topology by [3 + 2 + 4]‐c strategy. The formation of sur‐a topological structures relies on an elongated [3 + 2]‐c tetrahedral thiazolo[5,4‐d]thiazole (DTZ)‐based building block (DTZ‐CHO) with lower C 2 ‐symmetry. This unit is formed by inserting linear asymmetric DTZ subunit (2‐c vertex) between two 3‐c vertices. The incorporation of strong DTZ‐pyrene/vinyl electron D–A structures efficiently promote exciton separation and charge transfer during photocatalysis, thereby demonstrating high‐efficiency coupling photoactivation performance toward oxygen and biomass. It delivers a hydrogen peroxide photosynthesis rate of ∼12 092 µmol g −1  h −1 based on four‐step direct Yeager‐type oxygen photoreduction mechanism on DTZ active centers, pairing with efficient 5‐hydroxymethylfurfural photooxidation (∼10 264 µmol g −1  h −1 ). This work highlights the potential of topologically unique 3D COFs with robust D‐A structures as high‐efficiency photocatalysts for artificial photosynthesis.