Reversing Surface Charge for Highly-Active Organic Photovoltaic Catalysts

Shichao Wu; Zhenzhen Zhang; Yuhsuan Lee; Yawen Li; Xuefeng Tai; Wenqin Si; Shuming Bai; Yuze Lin

doi:10.1002/anie.202422779

Reversing Surface Charge for Highly-Active Organic Photovoltaic Catalysts

Angew Chem Int Ed Engl. 2024 Dec 23:e202422779. doi: 10.1002/anie.202422779. Online ahead of print.

Authors

Shichao Wu^{1

2}, Zhenzhen Zhang^{1

2}, Yuhsuan Lee^{1

2}, Yawen Li^{1

2}, Xuefeng Tai^{1

2}, Wenqin Si^{1

2}, Shuming Bai^{1

2}, Yuze Lin^{1

2}

Affiliations

¹ Beijing National Laboratory for Molecular Sciences, Laboratories of Organic Solids, and Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
² University of Chinese Academy of Sciences, Beijing, 100049, China.

PMID: 39714376
DOI: 10.1002/anie.202422779

Abstract

Organic photovoltaic materials typically exhibit low charge separation and transfer efficiency and severe exciton/carrier recombination due to high exciton binding energy and short exciton diffusion lengths, limiting the enhancement of photocatalytic hydrogen evolution performance. Here, we introduce a surface charge reversal strategy to regulate the charge character of organic photovoltaic catalyst (OPC). Compared to OPC nanoparticles (NPs) stabilized by an anionic surfactant ((-) NPs), NPs stabilized by a cationic surfactant ((+) NPs) exhibit a raised Fermi level, larger surface band bending and Schottky barrier, thereby enhancing charge separation and transfer efficiency while suppressing charge carrier recombination. As a result, (+) NPs demonstrate better photocatalytic performance than (-) NPs, independent of the chemical structure of OPCs and surfactant molecules. Under the illumination of AM1.5G, 100 mW cm^-2, the PM6: 2FBP-4F NPs stabilized by cationic surfactant (dodecyltrimethylammonium bromide, DTAB) exhibit much higher photocatalytic activity for hydrogen evolution (up to 946.1±15.76 mmol h^-1 g^-1) than that of PM6: 2FBP-4F NPs stabilized by anionic surfactant, among the best results reported so far for photocatalytic hydrogen evolution under simulated sunlight.

Keywords: Band Bending; Hydrogen Evolution; Organic Photovoltaic Catalyst; Surface Charge Reversal; Surfactant.

Abstract

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