A 1,3,5-triazine and benzodithiophene based donor-acceptor type semiconducting conjugated polymer for photocatalytic overall water splitting

Donor-acceptor domains hold the key to tailoring photochemical properties and charge carrier mobility of conjugated microporous polymers (CMPs) for application in photocatalytic water splitting. Herein, a family of electron-withdrawing 1,3,5-triazine and electron-donating fused thiophene based porous polymers are obtained via C-H arylation. The TBT-BDT showed an excellent HER of 4238 mu mol g-1 h-1, which is 17-fold and 3-fold higher than that of TBT-Th and TBT-TT, respectively. In addition, TBT-BDT facilitates overall water splitting to produce stoichiometric amounts of H2 (28 mu mol g-1 h-1) and O2 (14 mu mol g-1 h-1). The significant difference in the photocatalytic performance was mainly ascribed to the band structure change of the polymers, which underlined the importance of the donor unit on the performance of D-A type photocatalysts and indicated that thiophene-contained unit BDT is an excellent donor for high photocatalytic activity.