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:

Multi-cation perovskites prevent carrier reflection from grain surfaces

Nature Materials volume 19, pages 412–418 (2020)Cite this article

Subjects

Abstract

The composition of perovskite has been optimized combinatorially such that it often contains six components (AxByC1−x−yPbXzY3−z) in state-of-art perovskite solar cells. Questions remain regarding the precise role of each component, and the lack of a mechanistic explanation limits the practical exploration of the large and growing chemical space. Here, aided by transient photoluminescence microscopy, we find that, in perovskite single crystals, carrier diffusivity is in fact independent of composition. In polycrystalline thin films, the different compositions play a crucial role in carrier diffusion. We report that methylammonium (MA)-based films show a high carrier diffusivity of 0.047 cm2 s−1, while MA-free mixed caesium-formamidinium (CsFA) films exhibit an order of magnitude lower diffusivity. Elemental composition studies show that CsFA grains display a graded composition. This curtails electron diffusion in these films, as seen in both vertical carrier transport and surface potential studies. Incorporation of MA leads to a uniform grain core-to-edge composition, giving rise to a diffusivity of 0.034 cm2 s−1 in CsMAFA films. A model that invokes competing crystallization processes allows us to account for this finding, and suggests further strategies to achieve homogeneous crystallization for the benefit of perovskite optoelectronics.

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

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: TPLM.
Fig. 2: Carrier diffusion in single crystals as a function of composition.
Fig. 3: Carrier diffusion of perovskite thin films.
Fig. 4: Surface potential and vertical charge transfer studies in perovskite films.
Fig. 5: Grain formation in perovskites.

Similar content being viewed by others

Data availability

The authors declare that the main data supporting the findings of this study are available within the article and its Supplementary information. Extra data are available from the authors upon request.

References

  1. Kojima, A., Teshima, K., Shirai, Y. & Miyasaka, T. Organometal halide perovskites as visible-light sensitizers for photovoltaic cells. J. Am. Chem. Soc. 131, 6050–6051 (2009).

    Article  CAS  Google Scholar 

  2. Im, J.-H., Lee, C.-R., Lee, J.-W., Park, S.-W. & Park, N.-G. 6.5% efficient perovskite quantum-dot-sensitized solar cell. Nanoscale 3, 4088 (2011).

    Article  CAS  Google Scholar 

  3. Kim, H.-S. et al. Lead iodide perovskite sensitized all-solid-state submicron thin film mesoscopic solar cell with efficiency exceeding 9%. Sci. Rep. 2, 591 (2012).

    Article  CAS  Google Scholar 

  4. Lee, M. M., Teuscher, J. J., Miyasaka, T., Murakami, T. N. & Snaith, H. J. Efficient hybrid solar cells based on meso-superstructured organometal halide perovskites. Science 338, 643–647 (2012).

    Article  CAS  Google Scholar 

  5. Burschka, J. et al. Sequential deposition as a route to high-performance perovskite-sensitized solar cells. Nature 499, 316–320 (2013).

    Article  CAS  Google Scholar 

  6. Best Research-Cell Efficiency Chart (NREL, accessed 10 October 2019); https://www.nrel.gov/pv/cell-efficiency.html

  7. deQuilettes, D. W. et al. Impact of microstructure on local carrier lifetime in perovskite solar cells. Science 348, 683–686 (2015).

    Article  CAS  Google Scholar 

  8. Hou, Y. et al. A generic interface to reduce the efficiency-stability-cost gap of perovskite solar cells. Science 358, 1192–1197 (2017).

    Article  CAS  Google Scholar 

  9. Guo, Z. et al. Long-range hot-carrier transport in hybrid perovskites visualized by ultrafast microscopy. Science 356, 59–62 (2017).

    Article  CAS  Google Scholar 

  10. Davies, C. L. et al. Bimolecular recombination in methylammonium lead triiodide perovskite is an inverse absorption process. Nat. Commun. 9, 293 (2018).

    Article  CAS  Google Scholar 

  11. Abdi-Jalebi, M. et al. Maximizing and stabilizing luminescence from halide perovskites with potassium passivation. Nature 555, 497–501 (2018).

    Article  CAS  Google Scholar 

  12. Tsai, H. et al. High-efficiency two-dimensional Ruddlesden–Popper perovskite solar cells. Nature 536, 312–316 (2016).

    Article  CAS  Google Scholar 

  13. Dastidar, S. et al. High chloride doping levels stabilize the perovskite phase of cesium lead iodide. Nano Lett. 16, 3563–3570 (2016).

    Article  CAS  Google Scholar 

  14. Cho, H. et al. Overcoming the electroluminescence efficiency limitations of perovskite light-emitting diodes. Science 350, 1222–1225 (2015).

    Article  CAS  Google Scholar 

  15. Wang, T. et al. Indirect to direct bandgap transition in methylammonium lead halide perovskite. Energy Environ. Sci. 10, 509–515 (2017).

    Article  CAS  Google Scholar 

  16. Schulz, P. et al. Electronic level alignment in inverted organometal perovskite solar cells. Adv. Mater. Interfaces 2, 1400532 (2015).

    Article  CAS  Google Scholar 

  17. Pellet, N. et al. Mixed-organic-cation perovskite photovoltaics for enhanced solar-light harvesting. Angew. Chem. Int. Ed. Engl. 53, 3151–3157 (2014).

    Article  CAS  Google Scholar 

  18. Li, Z. et al. Stabilizing perovskite structures by tuning tolerance factor: formation of formamidinium and cesium lead iodide solid-state alloys. Chem. Mater. 28, 284–292 (2016).

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

  20. 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  CAS  Google Scholar 

  21. Jeon, N. J. et al. Compositional engineering of perovskite materials for high-performance solar cells. Nature 517, 476–480 (2015).

    Article  CAS  Google Scholar 

  22. Tan, H. et al. Dipolar cations confer defect tolerance in wide-bandgap metal halide perovskites. Nat. Commun. 9, 3100 (2018).

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

  24. Lin, K. et al. Perovskite light-emitting diodes with external quantum efficiency exceeding 20 per cent. Nature 562, 245–248 (2018).

    Article  CAS  Google Scholar 

  25. Correa-Baena, J.-P. et al. Homogenized halides and alkali cation segregation in alloyed organic-inorganic perovskites. Science 363, 627–631 (2019).

    Article  CAS  Google Scholar 

  26. Dang, H. X. et al. Multi-cation synergy suppresses phase segregation in mixed-halide perovskites. Joule 3, 1746–1764 (2019).

    Article  CAS  Google Scholar 

  27. Akselrod, G. M. et al. Visualization of exciton transport in ordered and disordered molecular solids. Nat. Commun. 5, 3646 (2014).

    Article  CAS  Google Scholar 

  28. Shi, D. et al. Low trap-state density and long carrier diffusion in organolead trihalide perovskite single crystals. Science 347, 519–522 (2015).

    Article  CAS  Google Scholar 

  29. Dong, Q. et al. Electron-hole diffusion lengths >175 µm in solution-grown CH3NH3PbI3 single crystals. Science 347, 967–970 (2015).

    Article  CAS  Google Scholar 

  30. Pazos-Outon, L. M. et al. Photon recycling in lead iodide perovskite solar cells. Science 351, 1430–1433 (2016).

    Article  CAS  Google Scholar 

  31. Yang, Y. et al. Top and bottom surfaces limit carrier lifetime in lead iodide perovskite films. Nat. Energy 2, 16207 (2017).

    Article  CAS  Google Scholar 

  32. Ščajev, P. et al. Two regimes of carrier diffusion in vapor-deposited lead-halide perovskites. J. Phys. Chem. C Nanomater. Interfaces 121, 21600–21609 (2017).

    Article  CAS  Google Scholar 

  33. Guo, Z., Manser, J. S., Wan, Y., Kamat, P. V. & Huang, L. Spatial and temporal imaging of long-range charge transport in perovskite thin films by ultrafast microscopy. Nat. Commun. 6, 7471 (2015).

    Article  CAS  Google Scholar 

  34. Xing, G. et al. Long-range balanced electron- and hole-transport lengths in organic-inorganic CH3NH3PbI3. Science 342, 344–347 (2013).

    Article  CAS  Google Scholar 

  35. Stranks, S. D. et al. Electron-hole diffusion lengths exceeding 1 micrometer in an organometal trihalide perovskite absorber. Science 342, 341–344 (2013).

    Article  CAS  Google Scholar 

  36. Jeon, N. J. et al. Solvent engineering for high-performance inorganic–organic hybrid perovskite solar cells. Nat. Mater. 13, 897–903 (2014).

    Article  CAS  Google Scholar 

  37. Delor, M., Weaver, H. L., Yu, Q. & Ginsberg, N. S. Imaging material functionality through 3D nanoscale tracking of energy flow. Nat. Mater. 19, 56–62 (2020).

    Article  CAS  Google Scholar 

  38. deQuilettes, D. W. et al. Tracking photoexcited carriers in hybrid perovskite semiconductors: trap-dominated spatial heterogeneity and diffusion. ACS Nano 11, 11488–11496 (2017).

    Article  CAS  Google Scholar 

  39. Yang, M. et al. Do grain boundaries dominate non-radiative recombination in CH3NH3PbI3 perovskite thin films? Phys. Chem. Chem. Phys. 19, 5043–5050 (2017).

    Article  CAS  Google Scholar 

  40. Arias, D. H., Moore, D. T., Van De Lagemaat, J. & Johnson, J. C. Direct measurements of carrier transport in polycrystalline methylammonium lead iodide perovskite films with transient grating spectroscopy. J. Phys. Chem. Lett. 9, 5710–5717 (2018).

    Article  CAS  Google Scholar 

  41. Cho, K. T. et al. Highly efficient perovskite solar cells with a compositionally engineered perovskite/hole transporting material interface. Energy Environ. Sci. 10, 621–627 (2017).

    Article  CAS  Google Scholar 

  42. Luo, D. et al. Enhanced photovoltage for inverted planar heterojunction perovskite solar cells. Science 360, 1442–1446 (2018).

    Article  CAS  Google Scholar 

  43. Shin, S. S. et al. Colloidally prepared La-doped BaSnO3 electrodes for efficient, photostable perovskite solar cells. Science 6620, 167–171 (2017).

    Article  CAS  Google Scholar 

  44. 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  CAS  Google Scholar 

  45. Saidaminov, M. I. et al. Suppression of atomic vacancies via incorporation of isovalent small ions to increase the stability of halide perovskite solar cells in ambient air. Nat. Energy 3, 648–654 (2018).

    Article  CAS  Google Scholar 

  46. Nazarenko, O., Yakunin, S., Morad, V., Cherniukh, I. & Kovalenko, M. V. Single crystals of caesium formamidinium lead halide perovskites: solution growth and gamma dosimetry. NPG Asia Mater. 9, e373 (2017).

    Article  CAS  Google Scholar 

  47. Kadro, J. M., Nonomura, K., Gachet, D., Grätzel, M. & Hagfeldt, A. Facile route to freestanding CH3NH3PbI3 crystals using inverse solubility. Sci. Rep. 5, 11654 (2015).

    Article  Google Scholar 

  48. Quintero-Bermudez, R. et al. Compositional and orientational control in metal halide perovskites of reduced dimensionality. Nat. Mater. 17, 900–907 (2018).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

Material growth and characterization were supported by the US Department of the Navy, Office of Naval Research (grant award no. N00014-17-1-2524). Carrier diffusion imaging studies at MIT were supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under award no. DE-SC0019345. M.I.S. acknowledges the support of the Banting Postdoctoral Fellowship Program, administered by the Government of Canada. G.W. acknowledges support from the Natural Sciences and Engineering Research Council of Canada (NSERC). We thank R. Wolowiec, D. Kopilovic, L. Levina and E. Palmiano for their help during the course of the study, and P. Brodersen for performing XPS.

Author information

Author notes

  1. Makhsud I. Saidaminov

    Present address: Department of Chemistry and Electrical & Computer Engineering, Centre for Advanced Materials and Related Technologies (CAMTEC), University of Victoria, Victoria, British Columbia, Canada

  2. These authors contributed equally: Makhsud I. Saidaminov, Kristopher Williams, Mingyang Wei.

Authors and Affiliations

  1. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada

    Makhsud I. Saidaminov, Mingyang Wei, Andrew Johnston, Rafael Quintero-Bermudez, Maral Vafaie, Joao M. Pina, Andrew H. Proppe, Yi Hou, Grant Walters & Edward H. Sargent

  2. Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA

    Kristopher Williams & William A. Tisdale

  3. Department of Chemistry, University of Toronto, Toronto, Ontario, Canada

    Andrew H. Proppe & Shana O. Kelley

  4. Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada

    Shana O. Kelley

Authors
  1. Makhsud I. Saidaminov
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Kristopher Williams
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Mingyang Wei
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Andrew Johnston
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Rafael Quintero-Bermudez
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Maral Vafaie
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Joao M. Pina
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Andrew H. Proppe
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Yi Hou
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Grant Walters
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Shana O. Kelley
    View author publications

    You can also search for this author in PubMed Google Scholar

  12. William A. Tisdale
    View author publications

    You can also search for this author in PubMed Google Scholar

  13. Edward H. Sargent
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

M.I.S. and K.W. conceived the idea. M.I.S. and M.W. prepared samples and characterized them. K.W. analysed carrier diffusion imaging results and developed the model. A.J., R.Q.B., M.V., A.P., Y.H., J. P., G.W. and S.O.K. assisted with the experiments and discussions. W.A.T. and E.H.S. directed the overall research. M.I.S., K.W., W.A.T. and E.H.S. wrote the manuscript. All authors read and commented on the manuscript.

Corresponding authors

Correspondence to William A. Tisdale or Edward H. Sargent.

Ethics declarations

Competing interests

The authors declare no competing interests.

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. 1–18, Methods 1.1–1.8 and 2.1–2.2, Tables 1–4 and refs. 1–9.

Reporting Summary

Supplementary Video 1

Two-dimensional carrier diffusion in MAPbI3 single crystal.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Saidaminov, M.I., Williams, K., Wei, M. et al. Multi-cation perovskites prevent carrier reflection from grain surfaces. Nat. Mater. 19, 412–418 (2020). https://doi.org/10.1038/s41563-019-0602-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41563-019-0602-2

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