Construction of Benzodithiophene-Based Donor–Acceptor-Type Covalent Triazine Frameworks with Tunable Structure for Photocatalytic Hydrogen Evolution

The introduction of donor–acceptor (D–A) motifs into organic semiconductors has been considered as one of the effective strategies to regulate photocatalytic activity. Herein, D–A-type benzodithiophene-based covalent triazine framework materials (BDT-CTFs) have been reported. It has been shown that the valence band and conduction band positions, band gaps, and electron–hole separation efficiency can be adjusted by altering the D/A ratio in the BDT-CTF photocatalytic materials. It has been revealed that the high electron–hole separation, migration efficiency, and low electron–hole recombination rates, as well as the special D–A pore structures are the main reasons for the higher photocatalytic hydrogen evolution reaction (HER) activities of BDT-CTF-1 materials. This work revealed the structure–activity relationship in BDT-based CTFs with different D–A ratios, providing a strategy to develop organic photocatalysts with high performance.