Carrier recombination in polymer photocatalysts involves both undissociated exciton decay and charge recombination, which are the main obstacles limiting their photocatalytic activity. Achieving efficient charge generation and separation in a polymer system is a fundamental strategy for the potential success of solar energy conversion to hydrogen, but it remains a huge challenge. In this study, we propose an innovative intermolecular π–π stacking strategy to construct a π-delocalized all-polymer S-scheme heterojunction for photocatalytic hydrogen evolution. Two conjugated porous polymers (CPPs)—PyB, composed of benzo[1,2-b:4,5-b′]dithiophene (BDT) and pyrene units, and PhB, composed of BDT and benzene—were synthesized and integrated with CN nanosheets. The highly planar and π-extended structure of PyB facilitated strong interfacial π–π stacking with CN, forming an extended π-delocalized network that enhanced the internal electric field (IEF), improved charge separation, and boosted visible-light absorption. As a result, the optimized PyB/CN-20 composite achieved a remarkable hydrogen evolution rate (HER) of 23.84 mmol?h?1?g?1?under visible light, approximately 287 times higher than that of pristine CN. This work underscores the critical role of polymer planarity and π-conjugation in heterojunction efficiency, and provides new insights into the rational design of π-delocalized S-scheme systems and establishes a general strategy for developing highly efficient, metal-free photocatalysts by leveraging molecular-level structural control.
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CN 35–1112/TQ, ISSN 0254–5861, Online ISSN: 2949-768X Copyright @ 2022 Chinese Journal of Structural Chemistry-www.Chinese Journal of Structural Chemistry.net. All Rights Reserved 閩ICP備2022002645號-1