Abstract
All-perovskite tandem solar cells (TSCs) offer exceptional performance and versatile applicability. However, a significant challenge persists in bridging the power conversion efficiency (PCE) gap between small- and large-area (>1 cm2) devices, which presents a formidable barrier to the commercialization of all-perovskite TSCs. Here we introduce a specialized crystal-modifying agent, piracetam, tailored for wide-bandgap perovskites, homogenizing top wide-bandgap subcells and enabling the construction of efficient large-area TSCs. Piracetam, featuring amide and pyrrolidone moieties, initially modulates perovskite nucleation, resulting in large-sized grains, preferred (110) orientation, enhanced crystallinity and uniform optoelectronic properties. During the subsequent annealing process, it further eliminates residual PbI2 and facilitates the formation of one-dimensional (Pi)PbI3 (Pi = piracetam) perovskite nanoneedles at the grain boundaries and surfaces. Consequently, single-junction 1.77 eV-bandgap solar cells achieve a certified open-circuit voltage of 1.36 V and a PCE of 20.35%. Furthermore, our monolithic two-terminal all-perovskite TSCs, with aperture areas of 0.07 cm2 and 1.02 cm2, yield PCEs of 28.71% (stabilized 28.55%, certified 28.13%) and 28.20% (stabilized 28.05%, certified 27.30%), respectively, demonstrating a minimal PCE loss of 0.51% when transitioning from small-area to large-area devices. In addition, piracetam demonstrates broad applicability across different perovskite compositions, increasing the PCE from 23.56% to 25.71% for single-junction 1.56 eV-bandgap counterparts. This method thus provides an effective pathway for scalable and efficient all-perovskite TSCs.
This is a preview of subscription content, access via your institution
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$32.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to the full article PDF.
USD 39.95
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
Data availability
All data are available in the main text or supplementary materials. Source data are provided with this paper.
References
He, R. et al. Improving interface quality for 1-cm2 all-perovskite tandem solar cells. Nature 618, 80–86 (2023).
Lin, R. et al. All-perovskite tandem solar cells with improved grain surface passivation. Nature 603, 73–78 (2022).
Chen, H. et al. Regulating surface potential maximizes voltage in all-perovskite tandems. Nature 613, 676–681 (2023).
Ding, B. et al. Dopant-additive synergism enhances perovskite solar modules. Nature 628, 299–305 (2024).
Best research-cell efficiency chart. National Renewable Energy Laboratory https://www.nrel.gov/pv/cell-efficiency.html (2025).
Leijtens, T., Bush, K. A., Prasanna, R. & McGehee, M. D. Opportunities and challenges for tandem solar cells using metal halide perovskite semiconductors. Nat. Energy 3, 828–838 (2018).
Jiang, Q. et al. Compositional texture engineering for highly stable wide-bandgap perovskite solar cells. Science 378, 1295–1300 (2022).
Lin, R. et al. All-perovskite tandem solar cells with 3D/3D bilayer perovskite heterojunction. Nature 620, 994–1000 (2023).
Yu, D. et al. Electron-withdrawing organic ligand for high-efficiency all-perovskite tandem solar cells. Nat. Energy 9, 298–307 (2024).
Li, N. et al. Liquid medium annealing for fabricating durable perovskite solar cells with improved reproducibility. Science 373, 561–567 (2021).
Zhou, Y., Poli, I., Meggiolaro, D., De Angelis, F. & Petrozza, A. Defect activity in metal halide perovskites with wide and narrow bandgap. Nat. Rev. Mater. 6, 986–1002 (2021).
Kim, D. H. et al. Bimolecular additives improve wide-band-gap perovskites for efficient tandem solar cells with CIGS. Joule 3, 1734–1745 (2019).
Yang, G. et al. Defect engineering in wide-bandgap perovskites for efficient perovskite–silicon tandem solar cells. Nat. Photon. 16, 588–594 (2022).
Yi, Z. et al. Achieving a high open-circuit voltage of 1.339 V in 1.77 eV wide-bandgap perovskite solar cells via self-assembled monolayers. Energy Environ. Sci. 17, 202–209 (2024).
Wang, R. et al. Efficient wide-bandgap perovskite photovoltaics with homogeneous halogen-phase distribution. Nat. Commun. 15, 8899 (2024).
Liang, Z. et al. Homogenizing out-of-plane cation composition in perovskite solar cells. Nature 624, 557–563 (2023).
Park, S. M. et al. Low-loss contacts on textured substrates for inverted perovskite solar cells. Nature 624, 289–294 (2023).
Luo, Y. et al. Enhanced efficiency and stability of wide-bandgap perovskite solar cells via molecular modification with piperazinium salt. Adv. Energy Mater. 14, 2304429 (2024).
McMeekin, D. P. et al. A mixed-cation lead mixed-halide perovskite absorber for tandem solar cells. Science 351, 151–155 (2016).
Wang, J. et al. Halide homogenization for low energy loss in 2-eV-bandgap perovskites and increased efficiency in all-perovskite triple-junction solar cells. Nat. Energy 9, 70–80 (2024).
Xiao, K. et al. All-perovskite tandem solar cells with 24.2% certified efficiency and area over 1 cm2 using surface-anchoring zwitterionic antioxidant. Nat. Energy 5, 870–880 (2020).
Xiao, K. et al. Scalable processing for realizing 21.7%-efficient all-perovskite tandem solar modules. Science 376, 762–767 (2022).
Li, Z. et al. In situ epitaxial growth of blocking structure in mixed-halide wide-band-gap perovskites for efficient photovoltaics. Joule 7, 1363–1381 (2023).
Ma, C. et al. Unveiling facet-dependent degradation and facet engineering for stable perovskite solar cells. Science 379, 173–178 (2023).
Zheng, X. et al. Managing grains and interfaces via ligand anchoring enables 22.3%-efficiency inverted perovskite solar cells. Nat. Energy 5, 131–140 (2020).
Shen, X. et al. Chloride-based additive engineering for efficient and stable wide-bandgap perovskite solar cells. Adv. Mater. 35, 2211742 (2023).
Chen, B., Rudd, P. N., Yang, S., Yuan, Y. & Huang, J. Imperfections and their passivation in halide perovskite solar cells. Chem. Soc. Rev. 48, 3842–3867 (2019).
Cheng, W., He, X., Wang, J.-G., Tian, W. & Li, L. N-(2-aminoethyl) acetamide additive enables phase-pure and stable α-FAPbI3 for efficient self-powered photodetectors. Adv. Mater. 34, 2208325 (2022).
Shao, Y. et al. Grain boundary dominated ion migration in polycrystalline organic–inorganic halide perovskite films. Energy Environ. Sci. 9, 1752–1759 (2016).
Zhu, J. et al. A donor–acceptor-type hole-selective contact reducing non-radiative recombination losses in both subcells towards efficient all-perovskite tandems. Nat. Energy 8, 714–724 (2023).
Zhou, S. et al. Aspartate all-in-one doping strategy enables efficient all-perovskite tandems. Nature 624, 69–73 (2023).
Wen, J. et al. Heterojunction formed via 3D-to-2D perovskite conversion for photostable wide-bandgap perovskite solar cells. Nat. Commun. 14, 7118 (2023).
Zhao, D. et al. Efficient two-terminal all-perovskite tandem solar cells enabled by high-quality low-bandgap absorber layers. Nat. Energy 3, 1093–1100 (2018).
Zhao, D. et al. Low-bandgap mixed tin–lead iodide perovskite absorbers with long carrier lifetimes for all-perovskite tandem solar cells. Nat. Energy 2, 17018 (2017).
Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metals. Phys. Rev. B 47, 558–561 (1993).
Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).
Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).
Grimme, S., Antony, J., Ehrlich, S. & Krieg, H. A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu. J. Chem. Phys. 132, 154104 (2010).
Li, X.-F. et al. Insights into to the KX (X = Cl, Br, I) adsorption-assisted stabilization of CsPbI2Br surface. Small 18, 2202623 (2022).
Jain, D., Chaube, S., Khullar, P., Goverapet Srinivasan, S. & Rai, B. Bulk and surface DFT investigations of inorganic halide perovskites screened using machine learning and materials property databases. Phys. Chem. Chem. Phys. 21, 19423–19436 (2019).
Momma, K. & Izumi, F. VESTA 3 for three-dimensional visualization of crystal, volumetric and morphology data. J. Appl. Crystallogr. 44, 1272–1276 (2011).
Wang, V., Xu, N., Liu, J.-C., Tang, G. & Geng, W.-T. VASPKIT: a user-friendly interface facilitating high-throughput computing and analysis using VASP code. Comput. Phys. Commun. 267, 108033 (2021).
Acknowledgements
This work was supported by the Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education of China, Wuhan University. We thank the Core Facility of Wuhan University for 1H NMR, DLS (Zetasizer Nano ZSP), FTIR, TOF-SIMS and SEM measurements, and beamlines BL14B1 and BL03HB at the Shanghai Synchrotron Radiation Facility (SSRF) for providing the beam time. We thank Y. Zhang from the Core Facility of Wuhan University for her help with TOF-SIMS analysis. We also acknowledge the financial support from the National Natural Science Foundation of China (grant numbers 12174290 (W.K.), 12134010 (G.F.), 12104345 (W.M.) and 210972127 (S.Z.)).
Author information
Authors and Affiliations
Contributions
S.F. and W.K. conceived the idea and designed the experiments. S.F., S.Z. and J.Z. developed the tandem solar cells. W.M. performed the DFT calculations and theoretical analysis. S.F. and G.L. developed the large-area tandem solar cells. Chen Wang conducted the SCLC measurements. H.G., W.S. and C.X. performed the AFM/KPFM characterization and analysis. L.H. conducted the C–V measurements and analysis. D.P. characterized the morphology of perovskite films and conducted the blade-coated WBG PSCs. Cheng Wang and T.W. conducted the TA measurements. G.C. and P.J. conducted the in situ PL measurements. K.D. and J.W. conducted the XRD measurements and their analysis. Z.X. conducted the normal-bandgap solar cells. Z.S. and X.G. conducted the in situ GIWAXS measurements. H.C. conducted the single-crystal characterization. S.F. and W.K. wrote the first draft of the paper. All authors discussed the results and contributed to the revisions of the paper. G.F. and W.K. supervised the project.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing interests.
Peer review
Peer review information
Nature Nanotechnology thanks the anonymous reviewers for their contribution to the peer review of this work.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Supplementary Information (download PDF )
Supplementary Figs. 1–47 and Tables 1–8.
Source data
Source Data Fig. 1 (download XLSX )
A single file containing all source data.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Fu, S., Zhou, S., Meng, W. et al. Piracetam shapes wide-bandgap perovskite crystals for scalable perovskite tandems. Nat. Nanotechnol. 20, 764–771 (2025). https://doi.org/10.1038/s41565-025-01899-z
Received:
Accepted:
Published:
Version of record:
Issue date:
DOI: https://doi.org/10.1038/s41565-025-01899-z
This article is cited by
-
Highly stable all-perovskite tandem solar cells with targeted conversion of tin–lead surfaces
Nature Photonics (2026)
-
Key Advancements and Emerging Trends of Perovskite Solar Cells in 2024–2025
Nano-Micro Letters (2026)
-
Scalable perovskite tandems enabled by dual-stage molecular regulation
Nature Nanotechnology (2025)
-
Performance-limiting metastable intragrain impurity nanoclusters in metal halide perovskites
Nature Communications (2025)
