Enhanced Photocatalytic Performance of Donor–Acceptor-Type Polymers Based on a Thiophene-Contained Polycyclic Aromatic Unit

Donor–acceptor (D–A)-type photocatalysts containing the polycyclic aromatic donor (BTT-CPP) and nonpolycyclic aromatic donor (TTB-CPP) are designed and synthesized. Their physicochemical properties are thoroughly investigated. The photocatalytic hydrogen generation experiments show that both polymers exhibit distinct photocatalytic performance. BTT-CPP displays an attractive hydrogen evolution rate (HER) of 37,866 μmol g^–1 h^–1 without further addition of the metal co-catalyst, one of the highest values reported for organic photocatalysts. The optimal HER of TTB-CPP is 8466 μmol g^–1 h^–1. These results highlight the important role of the donor unit on the performance of D–A-type photocatalysts and demonstrate that thiophene-contained polycyclic aromatic unit BTT is an excellent donor unit for high HER photocatalysts.