Abstract
The pursuit of simple yet high-performance materials is important for advancing organic photovoltaics, though structurally simple polymer donors typically underperform. This study reveals precise control over polymer aggregation and donor-acceptor compatibility is key to optimizing active layer morphology. We design three linear conjugated polymers with systematically chlorinated backbones to finely modulate aggregation tendency and surface tension. This strategy concurrently regulates film-formation kinetics and donor-acceptor compatibility. PTTz-Cl50 exhibits ideal aggregation and optimal compatibility with BTP-eC9, enabling sequential deposition that forms a bicontinuous interpenetrating network with appropriate domain size and marked phase purity. This microstructure provides sufficient interfacial area for exciton dissociation while retaining high-purity charge transport pathways. Consequently, the device demonstrates rapid exciton dissociation, efficient charge transport, and suppressed recombination, enhancing both short-circuit current and fill factor. This yield a high power conversion efficiency of 20.42% for linear conjugated polymers, underscoring the promise of low-cost materials for efficient devices.
Data availability
The data supporting the findings of this study are available within the published article and Supplementary Information. The X-ray crystallographic coordinates for structures reported in this study have been deposited at the Cambridge Crystallographic Data Centre (CCDC), under deposition numbers 2522480 (3 T) and 2522481 (3T-Cl). These data can be obtained free of charge from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif. Source data are provided with this paper.
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Acknowledgements
The research was supported by National Key Research and Development Program of China: 2024YFB4611500 (C.D.), National Natural Science Foundation of China: 22275058 (C.D.), 22405092 (B.W.), 52403225 (X.Y.), Guangdong Provincial Science and Technology Plan Project: 2023A0505010003 (C.D.), Guangdong Basic and Applied Basic Research Foundation: 2022B1515120008 (C.D.), 2025A1515010221 (B.W.), and Guangdong Innovative and Entrepreneurial Research Team Program: 2019ZT08L075 (C.D.), and China Postdoctoral Science Foundation: GZC20250122 (B.Y.), 2025M770181 (B.Y.), 2023TQ0120 (X.Y.), GZB20230223 (X.Y.). We also gratefully acknowledge the staff members of the Very Small Angle Neutron Scattering and Small Angle Neutron Scattering at the China Spallation Neutron Source (CSNS), especially Dr. Qing Chen and Dr. Zhenhua Xie for providing technical support, and thank Prof. Long Ye and Saimeng Li from Tianjin University for their assistance with GIWAXS analysis.
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C.D. conceived the idea and supervised the project. B.Y. performed device fabrication and data analysis. Z.C. and B.W. synthesized the polymers. X.Y. performed the synthesis complexity analysis. C.X. and X.Z. contributed to the single crystal structure analysis. J.Z. and W.Z. performed the transient absorption measurements and data analysis. S.L. and C.Y. performed the GIWAXS analysis. W.C. and G.Z. did the energy loss measurement. L.Z. did the in-situ absorption measurement. L.W. performed the SANS measurement and analysis. Z.L., F.H., and Y.C. participated in project administration. B.Y., Z.C., B.W., and C.D. prepared the manuscript. All authors commented on the manuscript.
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Yin, B., Chen, Z., Wu, B. et al. Chlorination-controlled aggregation and film-formation kinetics enabling high-efficiency organic solar cells with low-cost linear conjugated polymers. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69051-6
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DOI: https://doi.org/10.1038/s41467-026-69051-6
