A Carboxylate‐based Hydrophilic Organic Photovoltaic Catalyst with a Large Molecular Dipole Moment for High‐Performance Photocatalytic Hydrogen Evolution

• DOI: 10.1002/ange.202503792
• Publication Date: 2025-04-24T10:13:55Z
• Authors: Hua Sun; Jianan Fan; Rong Fan; Po Sun; Shifan Wang; Danfeng Wang; Peiyang Gu; Wenyi Tan; Yongfa Zhu
• Keywords: Carboxylate; Hydrogen molecule

Achieving ultrafast dissociation of photogenerated excitons and efficient charge transport within the photocatalyst is a fundamental issue. Additionally, enhancing interaction between semiconductors water crucial for photocatalytic splitting. Herein, we synthesized carboxylate‐based hydrophilic polymer, hPTB7‐Th. Exposed carboxylates enhance semiconductor‐water interfacial compatibility, reducing contact resistance accelerating transfer kinetics. Furthermore, carboxylate substitution shifts polarity centers, amplifying molecular dipole moment by 10‐fold. This induces giant built‐in electric field, enabling electron‐transfer process (ca. 0.31 ps) in hPTB7‐Th:PCBM bulk heterojunction. Consequently, hPTB7‐Th:PCBM‐based heterojunction nanoparticles exhibit excellent activity, achieving an optimal hydrogen evolution rate 111.5 mmol g‐1 h‐1, four times over ester‐based counterpart (PTB7‐Th:PCBM). Moreover, electrostatic stability imparted endows with outstanding operational stability, maintaining 81% its initial after 100 h operation. result places it among state‐of‐the‐art organic photovoltaic photocatalysts terms stability. work establishes engineering strategy high‐performance photocatalysts, emphasizing synergistic optimization hydrophilicity, engineering, dynamics.