Abstract
The environmental persistence of per- and polyfluoroalkyl substances (PFASs), driven by the exceptional stability of their C–F bonds, presents a formidable challenge for remediation. Herein, we report the 5,10,15,20-tetraphenyl (4-aminophenyl) porphyrin (TAPP) aggregates as visible-light-driven photocatalysts capable of achieving almost-100% defluorination of PFASs without chemical additives. Central to this process is the ultra-stable TAPP radical species (TAPP•), which exhibits a lifetime exceeding 7 days under ambient conditions. Under visible-light irradiation, TAPP• generates reductive electrons with a potential of −2.68 VNHE, enabling injection into the C–F antibonding orbitals to initiate defluorination. The exceptional stability of TAPP• arises from intramolecular charge delocalization mediated by the synergistic overlap between the lone-pair electrons distribution of the amino groups and the highest occupied molecular orbital. This work develops a steady radical strategy that leverages charge-delocalization to engineer photocatalysts with highly reductive electron, offering an approach to address persistent environmental contaminants.
Data availability
The data that supports the findings of the study are included in the main text and supplementary information files. Source Data file has been deposited in Figshare under accession code https://doi.org/10.6084/m9.figshare.31169650. Source data are provided with this paper.
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Acknowledgements
This work was supported by the National Science Foundation of China (22136002), the National Key Research and Development Project of China (2020YFA0710304), and the Special Fund Project of Jiangsu Province for Scientific and Technological Innovation in Carbon Peaking and Carbon Neutrality (BK20220023). Y.G. is supported by an RGC Postdoctoral Fellowship from the Research Grants Council of the Hong Kong Special Administrative Region, China (PDFS2324-7S05). We are grateful to Wenqing Yao, Jianxia Duan for their help with the XPS analysis; Zhanping Li and Chong Guo for TOF–SIMS; Yanfhai Jun and Wenyu Li for EPR and NMR; Qiang Han for LC-MS; Ruilong Zong, Chao Ma, and Qin Li at the Analysis Center of Tsinghua University for assistance with TEM and XRD. We thank the drug metabolism department of the Center of Pharmaceutical Technology (Tsinghua University), especially Fang Wei and Guofang Tian, for their help with LC–MS/MS and IC. We acknowledge the use of schematic icons designed by macrovector - Freepik.com under its Free License for use in Fig. 5a.
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C.M.C. executed the study development and prepared writing–original draft. C.M.C. J.Y.X., Z.H.W. performed data analysis and interpretation. E.W.Z. and W.L.L. participated in experimental design. Q.X.Z. and L.Z. performed DFT calculations. Y.G. and Y.F.Z. designed the study and supervised the manuscript. All authors read and edited the manuscript.
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Chong, M., Zhou, Q., Xu, J. et al. Complete defluorination of PFASs via photocatalytic reduction in water. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69933-9
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DOI: https://doi.org/10.1038/s41467-026-69933-9
