Abstract
Flexible solar cells have a transformative potential for niche applications, but they face fundamental challenges in simultaneously achieving high-power conversion efficiency (PCE), extreme mechanical resilience and operational stability1,2,3,4. Here we demonstrate a certified 33.6%-efficient flexible perovskite/crystalline silicon (c-Si) tandem solar cell with a record open-circuit voltage (Voc) of 2.015 V, rivalling its rigid counterpart. The flexible tandem retains 91% of its initial PCE after 5,000 cycles under a bending radius (Rb) of 17.6 mm and demonstrates exceptional operational and damp-heat stability, featuring a T80 lifetime exceeding 2,000 h under continuous illumination and retaining 90% of its initial PCE after a 1,000 h damp-heat test. This advancement is enabled by the implementation of the reactive-plasma-deposited (RPD) cerium and hydrogen co-doped indium oxide (ICO:H) recombination layer that promotes self-assembled monolayers (SAMs) coverage and interfacial charge transfer, and in situ annealed zinc-doped indium oxide (IZO) front transparent electrode with markedly enhanced optoelectronic and mechanical properties.
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All data are available in the main text or the Supplementary Information. Further data are available from the corresponding authors upon reasonable request.
References
Huang, S. et al. A review on flexible solar cells. Sci. China Mater. 67, 2717–2736 (2024).
Li, S., Li, Z., Wan, X. & Chen, Y. Recent progress in flexible organic solar cells. eScience 3, 100085 (2023).
Tian, R., Zhou, S., Meng, Y., Liu, C. & Ge, Z. Material and device design of flexible perovskite solar cells for next-generation power supplies. Adv. Mater. 36, 2311473 (2024).
Lee, D. S. et al. Overcoming stability limitations of efficient, flexible perovskite solar modules. Joule 8, 1380–1393 (2024).
Liu, Z. et al. All-perovskite tandem solar cells achieving >29% efficiency with improved (100) orientation in wide-bandgap perovskites. Nat. Mater. 24, 252–259 (2025).
Pei, F. et al. Inhibiting defect passivation failure in perovskite for perovskite/Cu(In,Ga)Se2 monolithic tandem solar cells with certified efficiency 27.35%. Nat. Energy 10, 824–835 (2025).
Brinkmann, K. O. et al. Perovskite–organic tandem solar cells. Nat. Rev. Mater. 9, 202–217 (2024).
Ugur, E. et al. Enhanced cation interaction in perovskites for efficient tandem solar cells with silicon. Science 385, 533–538 (2024).
Chen, Y. et al. Nuclei engineering for even halide distribution in stable perovskite/silicon tandem solar cells. Science 385, 554–560 (2024).
Mariotti, S. et al. Interface engineering for high-performance, triple-halide perovskite–silicon tandem solar cells. Science 381, 63–69 (2023).
Chin, X. Y. et al. Interface passivation for 31.25%-efficient perovskite/silicon tandem solar cells. Science 381, 59–63 (2023).
Liu, J. et al. Perovskite/silicon tandem solar cells with bilayer interface passivation. Nature 635, 596–603 (2024).
Kim, D. et al. Efficient, stable silicon tandem cells enabled by anion-engineered wide-bandgap perovskites. Science 368, 155–160 (2020).
Aydin, E. et al. Enhanced optoelectronic coupling for perovskite/silicon tandem solar cells. Nature 623, 732–738 (2023).
Liu, J. et al. Efficient and stable perovskite-silicon tandem solar cells through contact displacement by MgFx. Science 377, 302–306 (2022).
NREL. Best Research-Cell Efficiency Chart. Photovoltaic Research. https://www.nrel.gov/pv/cell-efficiency.html.
Mailoa, J. P. et al. A 2-terminal perovskite/silicon multijunction solar cell enabled by a silicon tunnel junction. Appl. Phys. Lett. 106, 121105 (2015).
Wang, X. et al. Ultrathin (∼30 µm) flexible monolithic perovskite/silicon tandem solar cell. Sci. Bull. 69, 1887–1894 (2024).
Shishido, H. et al. High-efficiency perovskite/silicon tandem solar cells with flexibility. Sol. RRL 9, 2400899 (2025).
Sun, Y. et al. Flexible perovskite/silicon monolithic tandem solar cells approaching 30% efficiency. Nat. Commun. 16, 5733 (2025).
Shi, J., Meng, F., Bao, J., Liu, Y. & Liu, Z. Surface scattering effect on the electrical mobility of ultrathin Ce doped In2O3 film prepared at low temperature. Mater. Lett. 225, 54–56 (2018).
Yu, C. et al. 26.6%-Efficiency Silicon heterojunction solar cell with high-quality cerium and hydrogen codoped indium oxide transparent electrode. ACS Energy Lett. 10, 2503–2511 (2025).
Kobayashi, E., Watabe, Y. & Yamamoto, T. High-mobility transparent conductive thin films of cerium-doped hydrogenated indium oxide. Appl. Phys. Express 8, 015505 (2015).
Ru, X. et al. Silicon heterojunction solar cells achieving 26.6% efficiency on commercial-size p-type silicon wafer. Joule 8, 1092–1104 (2024).
Lin, H. et al. Silicon heterojunction solar cells with up to 26.81% efficiency achieved by electrically optimized nanocrystalline-silicon hole contact layers. Nat. Energy 8, 789–799 (2023).
Li, Y. et al. Flexible silicon solar cells with high power-to-weight ratios. Nature 626, 105–110 (2024).
Tockhorn, P. et al. Nano-optical designs for high-efficiency monolithic perovskite–silicon tandem solar cells. Nat. Nanotechnol. 17, 1214–1221 (2022).
Bush, K. A. et al. 23.6%-efficient monolithic perovskite/silicon tandem solar cells with improved stability. Nat. Energy 2, 17009 (2017).
Hu, S. et al. Flexible perovskite-based multiple-junction photovoltaics. Joule 9, 101870 (2025).
Li, Z. et al. Hyperbranched polymer functionalized flexible perovskite solar cells with mechanical robustness and reduced lead leakage. Nat. Commun. 14, 6451 (2023).
Kan, C. et al. Efficient and stable perovskite-silicon tandem solar cells with copper thiocyanate-embedded perovskite on textured silicon. Nat. Photon. 19, 63–70 (2025).
Aydin, E. et al. Pathways toward commercial perovskite/silicon tandem photovoltaics. Science 383, eadh3849 (2024).
Duan, L. et al. Stability challenges for the commercialization of perovskite–silicon tandem solar cells. Nat. Rev. Mater. 8, 261–281 (2023).
Jošt, M. et al. 21.6%-Efficient monolithic perovskite/Cu(In,Ga)Se2 tandem solar cells with thin conformal hole transport layers for integration on rough bottom cell surfaces. ACS Energy Lett. 4, 583–590 (2019).
De Bastiani, M. et al. Recombination junctions for efficient monolithic perovskite-based tandem solar cells: physical principles, properties, processing and prospects. Mater. Horiz. 7, 2791–2809 (2020).
Isikgor, F. H. et al. Molecular engineering of contact interfaces for high-performance perovskite solar cells. Nat. Rev. Mater. 8, 89–108 (2023).
Liu, H. et al. Effect of annealing treatment on properties of Ce-doped indium oxide (ICO) transparent conductive oxide films. J. Mater. Sci. Mater. Electron. 34, 840 (2023).
Kim, J.-H. & Park, J.-W. Improving the flexibility of large-area transparent conductive oxide electrodes on polymer substrates for flexible organic light emitting diodes by introducing surface roughness. Org. Electron. 14, 3444–3452 (2013).
Kato, Y. et al. Silver iodide formation in methyl ammonium lead iodide perovskite solar cells with silver top electrodes. Adv. Mater. Interfaces 2, 1500195 (2015).
Domanski, K. et al. Not all that glitters is gold: metal-migration-induced degradation in perovskite solar cells. ACS Nano 10, 6306–6314 (2016).
Wu, S. et al. A chemically inert bismuth interlayer enhances long-term stability of inverted perovskite solar cells. Nat. Commun. 10, 1161 (2019).
Xiao, M. et al. Engineering amorphous–crystallized interface of ZrNx barriers for stable inverted perovskite solar cells. Adv. Mater. 35, 2301684 (2023).
Liu, W. et al. Flexible solar cells based on foldable silicon wafers with blunted edges. Nature 617, 717–723 (2023).
Yu, C. et al. Industrial-scale deposition of nanocrystalline silicon oxide for 26.4%-efficient silicon heterojunction solar cells with copper electrodes. Nat. Energy 8, 1375–1385 (2023).
Acknowledgements
X.Y. acknowledges financial support from the National Natural Science Foundation of China (no. 62174114 and no. U24A2063), the National Key R&D program of China (no. 2022YFB4200203), the Department of Science and Technology of Jiangsu Province (BE2022023). X.Z. acknowledges financial support from the Key Project of Jiangsu Provincial Basic Research Plan (no. BK20243031), Suzhou Laboratory–GCL–Soochow University Joint Laboratory for Perovskite Photovoltaics and the Collaborative Innovation Center of Suzhou Nano Science and Technology.
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Contributions
X.Y. conceived the idea, designed the overall experiments and led the project. X.Y. and S.W wrote the paper. S.W., W. Li, C.Y. and W.S. fabricated the tandem devices and performed the characterization and analysis. Q.K. performed the TEM characterization and analysis. F.C., K.G., L.Y. and B.Y. contributed to characterizations and data interpretation. J.Z., S.Y., Q.W., Q.F. and X.C. designed and fabricated the silicon bottom cells. G.C. performed the molecular dynamics simulations. P.C. and W. Liu helped with the three-point bending test and analysis. Z.L., W.-C.H., Z.Y. and Y.B. helped with the stability tests. S.D.W., X.Y. and X.Z. supervised this project. All authors contributed to the discussion of the results and revision of the paper.
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J.Z., S.Y., Q.W., Q.F. and X.C. are employees of Suzhou Maxwell Technologies. Z.L. and W.-C.H. are employees of Chint New Energy Technology. The other authors declare no competing interests.
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Extended data figures and tables
Extended Data Fig. 1 Flexible tandem performance with recombination layer and front electrode engineering.
PCE distribution of flexible tandems with in-situ annealed IZO electrode, ICO:H recombination layer, and in-situ annealed IZO + ICO:H recombination layer. The control device is with conventional ITO recombination layer (20 nm) and IZO front electrode without in-situ annealing. Thirty devices were fabricated for each condition. The top lines, bottom lines, lines in the box, square and boxes represent maximum values, minimum values, median values, mean values and 25–75% distributions, respectively.
Extended Data Fig. 2 Flexible tandem performance with and without rear reflector (RR).
a, Box plot of Jsc for devices with and without RR, indicating an absolute Jsc gain of 0.4 mA.cm−2. Twenty devices were fabricated for each condition. The top lines, bottom lines, lines in the box, square and boxes represent maximum values, minimum values, median values, mean values and 25–75% distributions, respectively. b, 1-R of the flexible tandem with and without RR within the wavelength range of 900–1180 nm. c, J-V curves for the flexible tandems with and without RR.
Extended Data Fig. 3 Performance of rigid tandem.
a, The J-V curve and b, EQE curve of rigid tandem with identical ICO:H recombination layer and in-situ annealed IZO on a thick SHJ bottom cell (∼120 µm). c, EQE curves of the SHJ subcell with different substrate thickness, demonstrating the reduced EQE response in the NIR when decreasing the substrate thickness.
Extended Data Fig. 4 Effect of ICO:H recombination layer thickness on the performance of flexible tandems.
a, Voc. b, FF. c, Jsc. d, PCE. The curves are normal distributions from six devices.
Extended Data Fig. 5 Effect of in-situ annealing temperature on the performance of flexible tandems with ICO:H recombination layer.
a, Voc. b, Jsc. c, FF. Fifteen devices were fabricated for each condition. The top lines, bottom lines, lines in the box, square and boxes represent maximum values, minimum values, median values, mean values and 25–75% distributions, respectively.
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Wang, S., Li, W., Yu, C. et al. Flexible perovskite/silicon tandem solar cells with 33.6% efficiency. Nature 649, 59–64 (2026). https://doi.org/10.1038/s41586-025-09849-4
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DOI: https://doi.org/10.1038/s41586-025-09849-4
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