Enhanced Light‐Driven Hydrogen‐Production Activity Induced by Accelerated Interfacial Charge Transfer in Donor–Acceptor Conjugated Polymers/TiO2 Hybrid

Abstract Donor–acceptor (D–A) conjugated polymers have proved to be desired candidates to couple with inorganic semiconductors for enhanced photocatalytic activity. Herein, the matched energy levels between polymer BFB and TiO 2 make them form BFB‐TiO 2 composites with moderate photocatalytic H 2 evolution rate (HER). To further enhance the interfacial interaction, BFB was modified with a carboxylic acid end group, which reacted with surface OH of TiO 2 to form an ester bond. As a result, the functionalized BFBA‐TiO 2 composites exhibited superior photocatalytic activity. Especially, HER of 4 % BFBA‐TiO 2 can reach up to 228.2 μmol h −1 under visible light irradiation (λ>420 nm), which is about 2.02 times higher than that of BFB‐TiO 2 . The enhanced photocatalytic activity originated from the formed ester bond between polymer and TiO 2 , and photogenerated electrons injection from lowest unoccupied molecular orbital (LUMO) of the exited polymer to conduction band of TiO 2 were accelerated. Therefore, based on an intermolecular interaction mechanism, more suitable D–A conjugated polymers with anchoring groups could be designed to couple with other semiconductors for enhancing photocatalytic activity.