Topology Regulation of Donor–Acceptor Conjugated Polymers for Solar‐Driven Hydrogen Production

Abstract Conjugated polymers, especially those with a donor–acceptor (D–A) structure, are emerging as potent photocatalysts for solar‐to‐chemical energy conversion. However, even constructed with identical D–A building blocks, conjugated polymers with diverse topologies can yield distinct photocatalytic properties, underscoring the significance of topology regulation. Herein, two conjugated polymers, Bi‐CBTP with a D‐A 2 motif and Tri‐CBTP with a D‐A 3 motif, were designed with identical building blocks, and synthesized via a low‐energy, rapid sonochemical method to investigate the influence of topologies on photocatalytic hydrogen production. Comprehensive theoretical calculations and femtosecond transient absorption (fs‐TA) spectroscopy reveal that the topology profoundly regulates the planarity, exciton binding energy, and electron push–pull effect of the D–A conjugated polymer. Specifically, Bi‐CBTP achieves a rather high hydrogen production rate of 516.7 mmol g −1 h −1 as the state‐of‐art performance under simulated solar irradiation, along with a 61.2% apparent quantum efficiency (AQE) at 420 nm. This work provides valuable insights into the design of high‐performance polymer photocatalysts for solar hydrogen production.