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Low-bandgap mixed tin–lead iodide perovskites with reduced methylammonium for simultaneous enhancement of solar cell efficiency and stability

Nature Energy volume 5, pages 768–776 (2020)Cite this article

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Abstract

High-performance perovskite/perovskite tandem solar cells require high-efficiency and stable low-bandgap perovskite subcells. State-of-the-art low-bandgap mixed tin–lead iodide perovskite solar cells exhibit either a high power-conversion efficiency or improved stability, but not both. Here we report a two-step bilayer interdiffusion growth process to simultaneously meet both requirements for formamidinium-based low-bandgap mixed tin–lead iodide perovskite solar cells. The bilayer interdiffusion growth process allows for the formation of high-quality and large-grained perovskite films with only 10 mol% volatile methylammonium. Additionally, one-dimensional pyrrolidinium perovskite was applied to passivate the perovskite film and improve the junction quality, which resulted in a carrier lifetime of 1.1 μs and an open circuit voltage of 0.865 V for our perovskite film and device with a bandgap of 1.28 eV. Our strategies enabled a power-conversion efficiency of 20.4% for low-bandgap perovskite solar cells under AM 1.5G illumination. More importantly, an encapsulated device can retain 92% of its initial efficiency after 450 h of continuous 1 sun illumination.

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Fig. 1: Mixed Sn–Pb perovskite films prepared by the BIG process.
Fig. 2: Composition and degradation of mixed Sn–Pb perovskite films fabricated by the BIG process.
Fig. 3: 1D PySnxPb1–xI3 passivation of mixed Sn–Pb perovskite thin films.
Fig. 4: Single-junction and tandem PSCs.

Data availability

All data generated or analysed during this study are included in the published article and its Supplementary Information.

References

  1. Best Research-Cell Efficiency Chart https://www.nrel.gov/pv/cell-efficiency.html (NREL, accessed 25 March 2020).

  2. Shockley, W. & Queisser, H. J. Detailed balance limit of efficiency of p–n junction solar cells. J. Appl. Phys. 32, 510–519 (1961).

    Google Scholar 

  3. Hörantner, M. T. et al. The potential of multijunction perovskite solar cells. ACS Energy Lett. 2, 2506–2513 (2017).

    Google Scholar 

  4. 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).

    Google Scholar 

  5. Eperon, G. E. et al. Perovskite–perovskite tandem photovoltaics with optimized band gaps. Science 354, 861–865 (2016).

    Google Scholar 

  6. Lin, R. et al. Monolithic all-perovskite tandem solar cells with 24.8% efficiency exploiting comproportionation to suppress Sn(ii) oxidation in precursor ink. Nat. Energy 4, 864–873 (2019).

    Google Scholar 

  7. Tong, J. et al. Carrier lifetimes of >1 μs in Sn–Pb perovskites enable efficient all-perovskite tandem solar cells. Science 364, 475–479 (2019).

    Google Scholar 

  8. Chen, B., Zheng, X., Bai, Y., Padture, N. P. & Huang, J. Progress in tandem solar cells based on hybrid organic–inorganic perovskites. Adv. Energy Mater. 7, 1602400 (2017).

    Google Scholar 

  9. Yang, Z. et al. Enhancing electron diffusion length in narrow-bandgap perovskites for efficient monolithic perovskite tandem solar cells. Nat. Commun. 10, 4498 (2019).

    Google Scholar 

  10. Prasanna, R. et al. Design of low bandgap tin–lead halide perovskite solar cells to achieve thermal, atmospheric and operational stability. Nat. Energy 4, 939–947 (2019).

    Google Scholar 

  11. Leijtens, T. et al. Tin–lead halide perovskites with improved thermal and air stability for efficient all-perovskite tandem solar cells. Sustain. Energy Fuels 2, 2450–2459 (2018).

    Google Scholar 

  12. Kapil, G. et al. Strain relaxation and light management in tin–lead perovskite solar cells to achieve high efficiencies. ACS Energy Lett. 4, 1991–1998 (2019).

    Google Scholar 

  13. Forgács, D. et al. Efficient monolithic perovskite/perovskite tandem solar cells. Adv. Energy Mater. 7, 1602121 (2017).

    Google Scholar 

  14. Wei, M. et al. Combining efficiency and stability in mixed tin–lead perovskite solar cells by capping grains with an ultrathin 2d layer. Adv. Mater. 32, 1907058 (2020).

    Google Scholar 

  15. Wang, C., Song, Z., Li, C., Zhao, D. & Yan, Y. Low‐bandgap mixed tin–lead perovskites and their applications in all‐perovskite tandem solar cells. Adv. Funct. Mater. 29, 1808801 (2019).

    Google Scholar 

  16. Xu, G. et al. Integrating ultrathin bulk–heterojunction organic semiconductor intermediary for high-performance low-bandgap perovskite solar cells with low energy loss. Adv. Funct. Mater. 28, 1804427 (2018).

    Google Scholar 

  17. Liao, W. et al. Fabrication of efficient low-bandgap perovskite solar cells by combining formamidinium tin iodide with methylammonium lead iodide. J. Am. Chem. Soc. 138, 12360–12363 (2016).

    Google Scholar 

  18. 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).

    Google Scholar 

  19. 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).

    Google Scholar 

  20. Li, C. et al. Reducing saturation-current density to realize high-efficiency low-bandgap mixed tin–lead halide perovskite solar cells. Adv. Energy Mater. 9, 1803135 (2019).

    Google Scholar 

  21. Li, C. et al. Methylammonium-mediated evolution of mixed-organic-cation perovskite thin films: a dynamic composition-tuning process. Angew. Chem. 56, 7674–7678 (2017).

    Google Scholar 

  22. Tang, S. et al. Composition engineering in doctor-blading of perovskite solar cells. Adv. Energy Mater. 7, 1700302 (2017).

    Google Scholar 

  23. Yang, M. et al. Perovskite ink with wide processing window for scalable high-efficiency solar cells. Nat. Energy 2, 17038 (2017).

    Google Scholar 

  24. Song, Z. et al. Probing the origins of photodegradation in organic–inorganic metal halide perovskites with time-resolved mass spectrometry. Sustain. Energy Fuels 2, 2460–2467 (2018).

    Google Scholar 

  25. Lang, F. et al. Influence of radiation on the properties and the stability of hybrid perovskites. Adv. Mater. 30, 1702905 (2018).

    Google Scholar 

  26. 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).

    Google Scholar 

  27. Juarez-Perez, E. J. et al. Photodecomposition and thermal decomposition in methylammonium halide lead perovskites and inferred design principles to increase photovoltaic device stability. J. Mater. Chem. A 6, 9604–9612 (2018).

    Google Scholar 

  28. Juarez-Perez, E. J., Ono, L. K. & Qi, Y. Thermal degradation of formamidinium based lead halide perovskites into sym-triazine and hydrogen cyanide observed by coupled thermogravimetry–mass spectrometry analysis. J. Mater. Chem. A 7, 16912–16919 (2019).

    Google Scholar 

  29. Prasanna, R. et al. Band gap tuning via lattice contraction and octahedral tilting in perovskite materials for photovoltaics. J. Am. Chem. Soc. 139, 11117–11124 (2017).

    Google Scholar 

  30. Yu, Y. et al. Improving the performance of formamidinium and cesium lead triiodide perovskite solar cells using lead thiocyanate additives. ChemSusChem 9, 3288–3297 (2016).

    Google Scholar 

  31. Xu, A. F. et al. Pyrrolidinium lead iodide from crystallography: a new perovskite with low bandgap and good water resistance. Chem. Commun. 55, 3251–3253 (2019).

    Google Scholar 

  32. Fan, J. et al. Thermodynamically self-healing 1d–3d hybrid perovskite solar cells. Adv. Energy Mater. 8, 1703421 (2018).

    Google Scholar 

  33. Jiang, Q. et al. Surface passivation of perovskite film for efficient solar cells. Nat. Photon. 13, 460–466 (2019).

    Google Scholar 

  34. Lian, X. et al. Highly efficient Sn/Pb binary perovskite solar cell via precursor engineering: a two-step fabrication process. Adv. Funct. Mater. 29, 1807024 (2019).

    Google Scholar 

  35. Jacobsson, T. J. et al. Unreacted PbI2 as a double-edged sword for enhancing the performance of perovskite solar cells. J. Am. Chem. Soc. 138, 10331–10343 (2016).

    Google Scholar 

  36. Ogomi, Y. et al. CH3NH3SnxPb(1–x)I3 perovskite solar cells covering up to 1060 nm. J. Phys. Chem. Lett. 5, 1004–1011 (2014).

    Google Scholar 

  37. Saliba, M. et al. Incorporation of rubidium cations into perovskite solar cells improves photovoltaic performance. Science 354, 206–209 (2016).

    Google Scholar 

  38. Lee, J.-W. et al. Formamidinium and cesium hybridization for photo- and moisture-stable perovskite solar cell. Adv. Energy Mater. 5, 1501310 (2015).

    Google Scholar 

  39. Yi, C. et al. Entropic stabilization of mixed A-cation ABX3 metal halide perovskites for high performance perovskite solar cells. Energy Environ. Sci. 9, 656–662 (2016).

    Google Scholar 

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

    Google Scholar 

  41. Im, J., Stoumpos, C. C., Jin, H., Freeman, A. J. & Kanatzidis, M. G. Antagonism between spin–orbit coupling and steric effects causes anomalous band gap evolution in the perovskite photovoltaic materials CH3NH3Sn1–xPbxI3. J. Phys. Chem. Lett. 6, 3503–3509 (2015).

    Google Scholar 

  42. Hao, F., Stoumpos, C. C., Chang, R. P. & Kanatzidis, M. G. Anomalous band gap behavior in mixed Sn and Pb perovskites enables broadening of absorption spectrum in solar cells. J. Am. Chem. Soc. 136, 8094–8099 (2014).

    Google Scholar 

  43. Harvey, S. P. et al. Mitigating measurement artifacts in TOF–SIMS analysis of perovskite solar cells. ACS Appl. Mater. Interfaces 11, 30911–30918 (2019).

    Google Scholar 

  44. 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).

    Google Scholar 

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

    Google Scholar 

  46. Yin, W.-J., Shi, T. & Yan, Y. Unusual defect physics in CH3NH3PbI3 perovskite solar cell absorber. Appl. Phys. Lett. 104, 063903 (2014).

    Google Scholar 

  47. 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).

    Google Scholar 

  48. Wang, C. et al. Understanding and eliminating hysteresis for highly efficient planar perovskite solar cells. Adv. Energy Mater. 7, 1700414 (2017).

    Google Scholar 

  49. Chen, C. et al. Achieving a high open-circuit voltage in inverted wide-bandgap perovskite solar cells with a graded perovskite homojunction. Nano Energy 61, 141–147 (2019).

    Google Scholar 

  50. Xiao, C. et al. Inhomogeneous doping of perovskite materials by dopants from hole-transport layer. Matter 2, 1–12 (2019).

    Google Scholar 

  51. Jackson, W. B., Amer, N. M., Boccara, A. C. & Fournier, D. Photothermal deflection spectroscopy and detection. Appl. Opt. 20, 1333–1344 (1981).

    Google Scholar 

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Acknowledgements

This material is based on work supported by the US Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) under the Solar Energy Technologies Office Award no. DE-EE0008753. The TPD-MS study was supported by the National Science Foundation under contract no. DMR-1807818. K.K.S. and R.J.E. were supported by the US Air Force Research Laboratory under agreement no. FA9453-18-2-0037, and N.S., B.S., N.J.P. and R.J.E. were supported by the US Air Force Research Laboratory under agreement no. FA9453-19-C-1002. The US Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon.

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Authors and Affiliations

  1. Department of Physics and Astronomy and Wright Center for Photovoltaics Innovation and Commercialization, The University of Toledo, Toledo, OH, USA

    Chongwen Li, Zhaoning Song, Cong Chen, Biwas Subedi, Niraj Shrestha, Kamala Khanal Subedi, Lei Chen, Dachang Liu, You Li, Michael J. Heben, Dewei Zhao, Randy J. Ellingson, Nikolas J. Podraza & Yanfa Yan

  2. Materials Science Center, National Renewable Energy Laboratory, Golden, CO, USA

    Chuanxiao Xiao, Steven P. Harvey, Chun-sheng Jiang & Mowafak Al-Jassim

  3. Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH, USA

    Yong-Wah Kim

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Contributions

C.L., Z.S. and Y.Y. conceived the project. C.L. carried out the single-junction low-bandgap cell and tandem cell fabrication. C.C. prepared the wide-bandgap cell and helped with the tandem cell fabrication. D.L. participated in the wide-bandgap cell fabrication. Z.S. conducted the TPD-MS measurements. C.X. and C.J. helped with the KPFM. B.S. conducted the PDS and SE measurement. S.P.H. conducted the TOF–SIMS measurement. N.S. and K.K.S. helped with the PL and TRPL measurements. L.C. and Y.L. participated in the characterization. Y.-W.K. helped with the 1H NMR measurements. C.L., Z.S. and Y.Y. analysed the data and wrote the manuscript. M.J.H., D.Z., RJ.E., N.J.P. and M.A.-J. helped with the manuscript preparation. All the authors discussed the results and commented on the manuscript. Y.Y. supervised the project.

Corresponding authors

Correspondence to Zhaoning Song or Yanfa Yan.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–32 and Tables 1 and 2.

Reporting Summary

Supplementary Data

Statistical source data for Supplementary Figs. 2 and 4, point data, error bars and PDS raw data for Supplementary Figs. 9 and 11b.

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Li, C., Song, Z., Chen, C. et al. Low-bandgap mixed tin–lead iodide perovskites with reduced methylammonium for simultaneous enhancement of solar cell efficiency and stability. Nat Energy 5, 768–776 (2020). https://doi.org/10.1038/s41560-020-00692-7

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