Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Non-volatile solid-state 4-(N-carbazolyl)pyridine additive for perovskite solar cells with improved thermal and operational stability

Nature Energy volume 10, pages 1427–1438 (2025)Cite this article

Subjects

Abstract

Liquid-state 4-tert-butylpyridine is essential for achieving high performance in n–i–p perovskite solar cells. 4-tert- Butylpyridine effectively dissolves the lithium bis(trifluoromethanesulfonyl)imide dopant and stabilizes lithium ions. However, its high volatility and corrosive nature can degrade the perovskite layer and promote the formation of byproducts and pinholes in the hole transport layer under thermal stress, ultimately compromising device stability. Here we introduce a non-volatile, solid-state alternative—4-(N-carbazolyl)pyridine (4CP)—which stabilizes lithium ions and facilitates the formation of lithium bis(trifluoromethanesulfonyl)imide complexes. Perovskite solar cells incorporating 4CP achieve a power conversion efficiency of 26.2% (25.8% certified) and maintain 80% of their initial performance for over 3,000 h at maximum power point tracking. The unencapsulated devices retain 90% of their initial efficiency after 200 thermal shock cycles between −80 °C and 80 °C, and under continuous exposure to 65 °C and 85 °C. The adoption of 4CP could help improve the stability of n–i–p perovskite solar cells.

This is a preview of subscription content, access via your institution

Access options

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

Fig. 1: Comparison of tBP and 4CP concerning volatility, solubility and crystallinity.
Fig. 2: Thermal stability of PSCs using tBP and 4CP.
Fig. 3: Ion migration and spiro-OMeTAD oxidation comparison of tBP and 4CP.
Fig. 4: Charge transport and conductivity of 4CP.
Fig. 5: PSC performance and stability.

Similar content being viewed by others

Data availability

The data that support the findings of this study are available within the Article and its Supplementary Information. Source data are provided with this paper.

References

  1. McMeekin, D. P. et al. A mixed-cation lead mixed-halide perovskite absorber for tandem solar cells. Science 351, 151–155 (2016).

    Article  Google Scholar 

  2. Saliba, M. et al. Cesium-containing triple cation perovskite solar cells: improved stability, reproducibility and high efficiency. Energy Environ. Sci. 9, 1989–1997 (2016).

    Article  Google Scholar 

  3. Jeon, N. J. et al. A fluorene-terminated hole-transporting material for highly efficient and stable perovskite solar cells. Nat. Energy 3, 682–689 (2018).

    Article  MathSciNet  Google Scholar 

  4. Yoo, J. J. et al. Efficient perovskite solar cells via improved carrier management. Nature 590, 587–593 (2021).

    Article  Google Scholar 

  5. Turren-Cruz, S.-H., Hagfeldt, A. & Saliba, M. Methylammonium-free, high-performance, and stable perovskite solar cells on a planar architecture. Science 362, 449–453 (2018).

    Article  Google Scholar 

  6. Jeong, J. et al. Pseudo-halide anion engineering for α-FAPbI3 perovskite solar cells. Nature 592, 381–385 (2021).

    Article  Google Scholar 

  7. Park, J. et al. Controlled growth of perovskite layers with volatile alkylammonium chlorides. Nature 616, 724–730 (2023).

    Article  Google Scholar 

  8. Kim, J. et al. Susceptible organic cations enable stable and efficient perovskite solar cells. Joule 9, 101879 (2025).

    Article  Google Scholar 

  9. Chen, H. et al. Improved charge extraction in inverted perovskite solar cells with dual-site-binding ligands. Science 384, 189–193 (2024).

    Article  Google Scholar 

  10. Peng, W. et al. Reducing nonradiative recombination in perovskite solar cells with a porous insulator contact. Science 379, 683–690 (2023).

    Article  Google Scholar 

  11. Li, G. et al. Highly efficient p–i–n perovskite solar cells that endure temperature variations. Science 379, 399–403 (2023).

    Article  Google Scholar 

  12. Li, B. et al. Highly efficient and scalable p–i–n perovskite solar cells enabled by poly-metallocene interfaces. J. Am. Chem. Soc. 146, 13391–13398 (2024).

    Article  Google Scholar 

  13. Li, Z. et al. Stabilized hole-selective layer for high-performance inverted p–i–n perovskite solar cells. Science 382, 284–289 (2023).

    Article  Google Scholar 

  14. Yang, W. S. et al. Iodide management in formamidinium-lead-halide–based perovskite layers for efficient solar cells. Science 356, 1376–1379 (2017).

    Article  Google Scholar 

  15. Jung, E. H. et al. Efficient, stable and scalable perovskite solar cells using poly(3-hexylthiophene). Nature 567, 511–515 (2019).

    Article  Google Scholar 

  16. Min, H. et al. Perovskite solar cells with atomically coherent interlayers on SnO2 electrodes. Nature 598, 444–450 (2021).

    Article  Google Scholar 

  17. Kim, C. et al. Trimming defective perovskite layer surfaces for high-performance solar cells. Energy Environ. Sci. 17, 8582–8592 (2024).

    Article  Google Scholar 

  18. Min, H. et al. Efficient, stable solar cells by using inherent bandgap of α-phase formamidinium lead iodide. Science 366, 749–753 (2019).

    Article  Google Scholar 

  19. Rombach, F. M., Haque, S. A. & Macdonald, T. J. Lessons learned from spiro-OMeTAD and PTAA in perovskite solar cells. Energy Environ. Sci. 14, 5161–5190 (2021).

    Article  Google Scholar 

  20. Ouedraogo, N. A. N. et al. Oxidation of spiro-OMeTAD in high-efficiency perovskite solar cells. ACS Appl. Mater. Interfaces 14, 34303–34327 (2022).

    Article  Google Scholar 

  21. Hawash, Z., Ono, L. K. & Qi, Y. Moisture and oxygen enhance conductivity of LiTFSI-doped spiro-MeOTAD hole transport layer in perovskite solar cells. Adv. Mater. Interfaces 3, 1600117 (2016).

    Article  Google Scholar 

  22. Juarez-Perez, E. J. et al. Role of the dopants on the morphological and transport properties of spiro-MeOTAD hole transport layer. Chem. Mater. 28, 5702–5709 (2016).

    Article  Google Scholar 

  23. Wang, S. et al. Unveiling the role of tBP–LiTFSI complexes in perovskite solar cells. J. Am. Chem. Soc. 140, 16720–16730 (2018).

    Article  Google Scholar 

  24. Jena, A. K., Ikegami, M. & Miyasaka, T. Severe morphological deformation of spiro-OMeTAD in (CH3NH3)PbI3 solar cells at high temperature. ACS Energy Lett. 2, 1760–1761 (2017).

    Article  Google Scholar 

  25. Shin, Y. S. et al. De-doping engineering for efficient and heat-stable perovskite solar cells. Joule 9, 101779 (2025).

    Article  Google Scholar 

  26. Al-Ashouri, A. et al. Conformal monolayer contacts with lossless interfaces for perovskite single junction and monolithic tandem solar cells. Energy Environ. Sci. 12, 3356–3369 (2019).

    Article  Google Scholar 

  27. Jegorovė, A. et al. Starburst carbazole derivatives as efficient hole transporting materials for perovskite solar cells. Sol. RRL 6, 2100877 (2022).

    Article  Google Scholar 

  28. Radhakrishna, K., Manjunath, S. B., Devadiga, D., Chetri, R. & Nagaraja, A. T. Review on carbazole-based hole transporting materials for perovskite solar cell. ACS Appl. Energy Mater. 6, 3635–3664 (2023).

    Article  Google Scholar 

  29. Puerto Galvis, C. E., González Ruiz, D. A., Martínez-Ferrero, E. & Palomares, E. Challenges in the design and synthesis of self-assembling molecules as selective contacts in perovskite solar cells. Chem. Sci. 15, 1534–1556 (2024).

    Article  Google Scholar 

  30. Wang, S. et al. Role of 4-tert-butylpyridine as a hole transport layer morphological controller in perovskite solar cells. Nano Lett. 16, 5594–5600 (2016).

    Article  Google Scholar 

  31. Habisreutinger, S. N., Noel, N. K., Snaith, H. J. & Nicholas, R. Investigating the role of 4-tert-butylpyridine in perovskite solar cells. Adv. Energy Mater. 7, 1601079 (2017).

    Article  Google Scholar 

  32. Kim, G. et al. Impact of strain relaxation on performance of α-formamidinium lead iodide perovskite solar cells. Science 370, 108–112 (2020).

    Article  Google Scholar 

  33. Kim, M. et al. Methylammonium chloride induces intermediate phase stabilization for efficient perovskite solar cells. Joule 3, 2179–2192 (2019).

    Article  Google Scholar 

  34. Duijnstee, E. A. et al. Understanding the degradation of methylenediammonium and its role in phase-stabilizing formamidinium lead triiodide. J. Am. Chem. Soc. 145, 10275–10284 (2023).

    Article  Google Scholar 

  35. Tian, L. et al. Divalent cation replacement strategy stabilizes wide-bandgap perovskite for Cu(In,Ga)Se2 tandem solar cells. Nat. Photon. 19, 479–485 (2025).

  36. Shibayama, N. et al. Control of molecular orientation of spiro-OMeTAD on substrates. ACS Appl. Mater. Interfaces 12, 50187–50191 (2020).

    Article  Google Scholar 

  37. Coropceanu, V. et al. Charge transport in organic semiconductors. Chem. Rev. 107, 926–952 (2007).

    Article  Google Scholar 

  38. Malinauskas, T. et al. Enhancing thermal stability and lifetime of solid-state dye-sensitized solar cells via molecular engineering of the hole-transporting material spiro-OMeTAD. ACS Appl. Mater. Interfaces 7, 11107–11116 (2015).

    Article  Google Scholar 

  39. Sanehira, E. M. et al. Influence of electrode interfaces on the stability of perovskite solar cells: reduced degradation using MoOx/Al for hole collection. ACS Energy Lett. 1, 38–45 (2016).

    Article  Google Scholar 

  40. Ye, L. et al. Superoxide radical derived metal-free spiro-OMeTAD for highly stable perovskite solar cells. Nat. Commun. 15, 7889 (2024).

    Article  Google Scholar 

  41. Cho, Y. et al. Elucidating mechanisms behind ambient storage-induced efficiency improvements in perovskite solar cells. ACS Energy Lett. 6, 925–933 (2021).

    Article  Google Scholar 

  42. Shen, Y., Deng, K., Chen, Q., Gao, G. & Li, L. Crowning lithium ions in hole-transport layer toward stable perovskite solar cells. Adv. Mater. 34, 2200978 (2022).

    Article  Google Scholar 

  43. Laoire, C. O., Mukerjee, S., Abraham, K. M., Plichta, E. J. & Hendrickson, M. A. Influence of nonaqueous solvents on the electrochemistry of oxygen in the rechargeable lithium−air battery. J. Phys. Chem. C 114, 9178–9186 (2010).

  44. Aetukuri, N. B. et al. Solvating additives drive solution-mediated electrochemistry and enhance toroid growth in non-aqueous Li–O2 batteries. Nat. Chem. 7, 50–56 (2015).

    Article  Google Scholar 

  45. Lamberti, F. et al. Evidence of spiro-OMeTAD de-doping by tert-butylpyridine additive in hole-transporting layers for perovskite solar cells. Chem 5, 1806–1817 (2019).

    Article  Google Scholar 

  46. Kim, S. et al. Enhancing thermal stability of perovskite solar cells through thermal transition and thin film crystallization engineering of polymeric hole transport layers. ACS Energy Lett. 9, 4501–4508 (2024).

    Article  Google Scholar 

  47. Yang, J. & Kelly, T. L. Decomposition and cell failure mechanisms in lead halide perovskite solar cells. Inorg. Chem. 56, 92–101 (2017).

    Article  Google Scholar 

  48. Divitini, G. et al. In situ observation of heat-induced degradation of perovskite solar cells. Nat. Energy 1, 15012 (2016).

    Article  Google Scholar 

  49. Li, H. et al. Dynamics parameter correction for predicting the long-term stability of organic photovoltaics. Macromolecules 57, 6548–6558 (2024).

    Article  Google Scholar 

  50. Hawash, Z., Ono, L. K., Raga, S. R., Lee, M. V. & Qi, Y. Air-exposure induced dopant redistribution and energy level shifts in spin-coated spiro-MeOTAD films. Chem. Mater. 27, 562–569 (2015).

    Article  Google Scholar 

  51. Pan, H. et al. Advances in design engineering and merits of electron transporting layers in perovskite solar cells. Mater. Horiz. 7, 2276–2291 (2020).

    Article  Google Scholar 

  52. Yao, Y. et al. Organic hole-transport layers for efficient, stable, and scalable inverted perovskite solar cells. Adv. Mater. 34, 2203794 (2022).

    Article  Google Scholar 

  53. Dong, Y. et al. Dopant-induced interactions in spiro-OMeTAD: advancing hole transport for perovskite solar cells. Mater. Sci. Eng. R 162, 100875 (2025).

    Article  Google Scholar 

  54. Euvrard, J. et al. p-Type molecular doping by charge transfer in halide perovskite. Mater. Adv. 2, 2956–2965 (2021).

    Article  Google Scholar 

  55. You, S. et al. Bifunctional hole-shuttle molecule for improved interfacial energy level alignment and defect passivation in perovskite solar cells. Nat. Energy 8, 515–525 (2023).

    Article  Google Scholar 

  56. Li, W. et al. Montmorillonite as bifunctional buffer layer material for hybrid perovskite solar cells with protection from corrosion and retarding recombination. J. Mater. Chem. A 2, 13587–13592 (2014).

    Article  Google Scholar 

  57. Domanski, K. et al. Migration of cations induces reversible performance losses over day/night cycling in perovskite solar cells. Energy Environ. Sci. 10, 604–613 (2017).

    Article  Google Scholar 

  58. Christians, J. A. et al. Tailored interfaces of unencapsulated perovskite solar cells for >1,000 hour operational stability. Nat. Energy 3, 68–74 (2018).

    Article  Google Scholar 

  59. Khenkin, M. V. et al. Consensus statement for stability assessment and reporting for perovskite photovoltaics based on ISOS procedures. Nat. Energy 5, 35–49 (2020).

    Article  Google Scholar 

  60. Lin, Y.-H. et al. A piperidinium salt stabilizes efficient metal-halide perovskite solar cells. Science 369, 96–102 (2020).

    Article  Google Scholar 

  61. Lang, F. et al. Radiation hardness and self-healing of perovskite solar cells. Adv. Mater. 28, 8726–8731 (2016).

    Article  Google Scholar 

  62. Tu, Y. et al. Perovskite solar cells for space applications: progress and challenges. Adv. Mater. 33, 2006545 (2021).

    Article  Google Scholar 

  63. Miyazawa, Y. et al. Tolerance of perovskite solar cell to high-energy particle irradiations in space environment. iScience 2, 148–155 (2018).

    Article  Google Scholar 

  64. Yang, J., Bao, Q., Shen, L. & Ding, L. Potential applications for perovskite solar cells in space. Nano Energy 76, 105019 (2020).

    Article  Google Scholar 

  65. Dong, B. et al. Self-assembled bilayer for perovskite solar cells with improved tolerance against thermal stresses. Nat. Energy 10, 342–353 (2025).

    Article  Google Scholar 

  66. Bulut, M. Thermal design, analysis, and testing of the first Turkish 3U communication CubeSat in low earth orbit. J. Therm. Anal. Calorim. 143, 4341–4353 (2021).

    Article  Google Scholar 

  67. Lamb, D. A., Irvine, S. J. C., Baker, M. A., Underwood, C. I. & Mardhani, S. Thin film cadmium telluride solar cells on ultra-thin glass in low earth orbit—3 years of performance data on the AlSat-1N CubeSat mission. Prog. Photovolt. Res. Appl. 29, 1000–1007 (2021).

    Article  Google Scholar 

  68. McAndrews, G. R. et al. Why perovskite thermal stress is unaffected by thin contact layers. Adv. Energy Mater. 14, 2400764 (2024).

    Article  Google Scholar 

  69. Valiev, M. et al. NWChem: a comprehensive and scalable open-source solution for large scale molecular simulations. Comput. Phys. Commun. 181, 1477–1489 (2010).

    Article  Google Scholar 

  70. Becke, A. D. Density-functional exchange-energy approximation with correct asymptotic behavior. Phys. Rev. A 38, 3098–3100 (1988).

    Article  Google Scholar 

  71. Lee, C., Yang, W. & Parr, R. G. Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density. Phys. Rev. B 37, 785–789 (1988).

    Article  Google Scholar 

  72. Plimpton, S. Fast parallel algorithms for short-range molecular dynamics. J. Comput. Phys. 117, 1–19 (1995).

    Article  Google Scholar 

  73. Jorgensen, W. L., Maxwell, D. S. & Tirado-Rives, J. Development and testing of the OPLS All-Atom force field on conformational energetics and properties of organic liquids. J. Am. Chem. Soc. 118, 11225–11236 (1996).

    Article  Google Scholar 

  74. Jensen, K. P. & Jorgensen, W. L. Halide, ammonium, and alkali metal ion parameters for modeling aqueous solutions. J. Chem. Theory Comput. 2, 1499–1509 (2006).

    Article  Google Scholar 

  75. Yeh, I.-C. & Berkowitz, M. L. Ewald summation for systems with slab geometry. J. Chem. Phys. 111, 3155–3162 (1999).

    Article  Google Scholar 

Download references

Acknowledgements

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (RS-2024-00338765, 2021R1A2C3004202), the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry and Energy (MOTIE) of the Republic of Korea (RS-2025-02309702) and the Nano and Material Technology Development Program through the NRF funded by the Ministry of Science and ICT (RS-2025-25442266).

Author information

Author notes

  1. These authors contributed equally: Kihoon Kim, Sangjin Yang.

Authors and Affiliations

  1. KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, South Korea

    Kihoon Kim, Chanhyeok Kim, Youngmin Kim, Jinsoo Park & Hanul Min

  2. School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan, South Korea

    Sangjin Yang, Jeewon Park, Seokhwan Jeong, Zhe Sun, Seung-Jae Shin & Changduk Yang

  3. Graduate School of Carbon Neutrality, Ulsan National Institute of Science and Technology, Ulsan, South Korea

    Minseok Kang & Changduk Yang

  4. Division of Advanced Materials, Korea Research Institute of Chemical Technology, Daejeon, South Korea

    Bong Joo Kang

  5. Space Testing Center, Korea Testing Laboratory, Jinju, South Korea

    Juhong Oh

  6. Department of Electrical and Electronic Engineering, Advanced Technology Institute, University of Surrey, Guildford, UK

    Jae Sung Yun

  7. Department of Integrative Energy Engineering, Korea University, Seoul, South Korea

    Hanul Min

Authors
  1. Kihoon Kim
    View author publications

    Search author on:PubMed Google Scholar

  2. Sangjin Yang
    View author publications

    Search author on:PubMed Google Scholar

  3. Chanhyeok Kim
    View author publications

    Search author on:PubMed Google Scholar

  4. Jeewon Park
    View author publications

    Search author on:PubMed Google Scholar

  5. Seokhwan Jeong
    View author publications

    Search author on:PubMed Google Scholar

  6. Youngmin Kim
    View author publications

    Search author on:PubMed Google Scholar

  7. Jinsoo Park
    View author publications

    Search author on:PubMed Google Scholar

  8. Zhe Sun
    View author publications

    Search author on:PubMed Google Scholar

  9. Minseok Kang
    View author publications

    Search author on:PubMed Google Scholar

  10. Bong Joo Kang
    View author publications

    Search author on:PubMed Google Scholar

  11. Juhong Oh
    View author publications

    Search author on:PubMed Google Scholar

  12. Jae Sung Yun
    View author publications

    Search author on:PubMed Google Scholar

  13. Seung-Jae Shin
    View author publications

    Search author on:PubMed Google Scholar

  14. Changduk Yang
    View author publications

    Search author on:PubMed Google Scholar

  15. Hanul Min
    View author publications

    Search author on:PubMed Google Scholar

Contributions

C.Y., H.M. and S.Y. conceived the idea. K.K. fabricated the PSCs and performed characterization of the perovskite films. S.Y. synthesized the 4CP and performed the related characterizations. C.K. carried out the model PSC fabrication. Jeewon Park carried out PL characterizations. S.J. carried out TGA and DSC characterization. Y.K. and Jinsoo Park performed SEM and conductivity measurement. Z.S. carried out in situ PL measurement. M.K. conducted ATR-FTIR measurements. B.J.K. carried out PLQY measurements. J.O. and J.S.Y. performed the thermal shock test. C.Y. supervised the project. S.-J.S. performed the theoretical simulation. The paper was mainly written by S.-J.S., C.Y. and H.M., and all authors commented on the paper.

Corresponding authors

Correspondence to Seung-Jae Shin, Changduk Yang or Hanul Min.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Energy thanks Thomas J. Macdonald, Jovana Milic and the other anonymous reviewer(s) 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

Supplementary Figs. 1–19 and Tables 1 and 2.

Reporting Summary

Supplementary Data

Source Data for Supplementary Fig. 18.

Source data

Source Data Fig. 2

Statistical source J–V data.

Source Data Fig. 5

Statistical source J–V data and source J–V curve.

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.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kim, K., Yang, S., Kim, C. et al. Non-volatile solid-state 4-(N-carbazolyl)pyridine additive for perovskite solar cells with improved thermal and operational stability. Nat Energy 10, 1427–1438 (2025). https://doi.org/10.1038/s41560-025-01864-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Version of record:

  • Issue date:

  • DOI: https://doi.org/10.1038/s41560-025-01864-z

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing