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Controlling competing photochemical reactions stabilizes perovskite solar cells

Abstract

Metal halide perovskites have become a popular material system for fabricating photovoltaics and various optoelectronic devices. However, long-term reliability must be assured. Instabilities are manifested as light-induced ion migration and segregation, which can lead to material degradation. Discordant reports have shown a beneficial role of ion migration under illumination, leading to defect healing. By combining ab initio simulations with photoluminescence measurements under controlled conditions, we demonstrate that photo-instabilities are related to light-induced formation and annihilation of defects acting as carrier trap states. We show that these phenomena coexist and compete. In particular, long-living carrier traps related to halide defects trigger photoinduced material transformations, driving both processes. Defect formation can be controlled by blocking under-coordinated surface sites, which act as a defect reservoir. By use of a passivation strategy we are thus able to stabilize the perovskite layer, leading to improved optoelectronic material quality and enhanced photostability in solar cells.

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Fig. 1: Transient integrated photoluminescence intensity from MAPbI3 and MAPbBr3 thin films as a function of excitation repetition rate and temperature.
Fig. 2: Transient integrated photoluminescence intensity from MAPbI3 thin films as a function of excitation penetration depth and excitation geometry.
Fig. 3: Defect dynamics.
Fig. 4: Photoluminescence enhancement and quenching mechanisms.
Fig. 5: Thin film passivation.

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Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding authors on reasonable request.

References

  1. NREL Best Research-Cell Efficiencies https://www.nrel.gov/pv/assets/images/efficiency-chart.png (2018).

  2. Xu, W. et al. Rational molecular passivation for high-performance perovskite light-emitting diodes. Nat. Photon. https://doi.org/10.1038/s41566-019-0390-x (2019).

    Article  ADS  Google Scholar 

  3. Lin, Q., Armin, A., Lyons, D. M., Burn, P. L. & Meredith, P. Low noise, IR-blind organohalide perovskite photodiodes for visible light detection and imaging. Adv. Mater. 27, 2060–2064 (2015).

    Article  Google Scholar 

  4. Wei, H. et al. Sensitive X-ray detectors made of methylammonium lead tribromide perovskite single crystals. Nat. Photon. 10, 333–339 (2016).

    Article  ADS  Google Scholar 

  5. Venugopalan, V. et al. High-detectivity perovskite light detectors printed in air from benign solvents. Chem 5, 868–880 (2019).

    Article  Google Scholar 

  6. Zhu, H. et al. Lead halide perovskite nanowire lasers with low lasing thresholds and high quality factors. Nat. Mater. 14, 636–642 (2015).

    Article  ADS  Google Scholar 

  7. Deschler, F. et al. High photoluminescence efficiency and optically pumped lasing in solution-processed mixed halide perovskite semiconductors. J. Phys. Chem. Lett. 5, 1421–1426 (2014).

    Article  Google Scholar 

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

    Article  ADS  Google Scholar 

  9. Johnston, M. B. & Herz, L. M. Hybrid perovskites for photovoltaics: charge-carrier recombination, diffusion and radiative efficiencies. Acc. Chem. Res. 49, 146–154 (2016).

    Article  Google Scholar 

  10. deQuilettes, D. W. et al. Photoluminescence lifetimes exceeding 8 μs and quantum yields exceeding 30% in hybrid perovskite thin films by ligand passivation. ACS Energy Lett. 1, 438–444 (2016).

    Article  Google Scholar 

  11. Ball, J. M. & Petrozza, A. Defects in perovskite-halides and their effects in solar cells. Nat. Energy 1, 16149 (2016).

    Article  ADS  Google Scholar 

  12. Meggiolaro, D. et al. Iodine chemistry determines the defect tolerance of lead-halide perovskites. Energy Environ. Sci. 11, 702–713 (2018).

    Article  Google Scholar 

  13. Hoke, E. T. et al. Reversible photo-induced trap formation in mixed-halide hybrid perovskites for photovoltaics. Chem. Sci. 6, 613–617 (2014).

    Article  Google Scholar 

  14. Sanchez, R. S. et al. Slow dynamic processes in lead halide perovskite solar cells. Characteristic times and hysteresis. J. Phys. Chem. Lett. 5, 2357–2363 (2014).

    Article  Google Scholar 

  15. Leijtens, T. et al. Mapping electric field-induced switchable poling and structural degradation in hybrid lead halide perovskite thin films. Adv. Energy Mater. 5, 1–11 (2015).

    Google Scholar 

  16. Gottesman, R. et al. Photoinduced reversible structural transformations in free-standing CH3NH3PbI3 perovskite films. J. Phys. Chem. Lett. 6, 2332–2338 (2015).

    Article  Google Scholar 

  17. Gottesman, R. & Zaban, A. Perovskites for photovoltaics in the spotlight: photoinduced physical changes and their implications. Acc. Chem. Res. 49, 320–329 (2016).

    Article  Google Scholar 

  18. Motti, S. G. et al. Photoinduced emissive trap states in lead halide perovskite semiconductors. ACS Energy Lett. 1, 726–730 (2016).

    Article  Google Scholar 

  19. Xing, J. et al. Ultrafast ion migration in hybrid perovskite polycrystalline thin films under light and suppression in single crystals. Phys. Chem. Chem. Phys. 18, 30484–30490 (2016).

    Article  Google Scholar 

  20. Kim, G. Y. et al. Large tunable photoeffect on ion conduction in halide perovskites and implications for photodecomposition. Nat. Mater. 17, 445–449 (2018).

    Article  ADS  Google Scholar 

  21. deQuilettes, D. W. et al. Photo-induced halide redistribution in organic–inorganic perovskite films. Nat. Commun. 7, 11683 (2016).

    Article  ADS  Google Scholar 

  22. Stranks, S. D. et al. Recombination kinetics in organic–inorganic perovskites: excitons, free charge and subgap states. Phys. Rev. Appl. 2, 034007 (2014).

    Article  ADS  Google Scholar 

  23. Mosconi, E., Meggiolaro, D., Snaith, H. J., Stranks, S. D. & De Angelis, F. Light-induced annihilation of Frenkel defects in organo–lead halide perovskites. Energy Environ. Sci. 9, 3180–3187 (2016).

    Article  Google Scholar 

  24. Chen, S. et al. Light illumination induced photoluminescence enhancement and quenching in lead halide perovskite. Sol. RRL 1, 1600001 (2017).

    Article  Google Scholar 

  25. Hong, D. et al. Nature of photo-induced quenching traps in methylammonium lead triiodide perovskite revealed by reversible photoluminescence decline. ACS Photon. 5, 2034–2043 (2018).

    Article  Google Scholar 

  26. Fang, H.-H. et al. Ultrahigh sensitivity of methylammonium lead tribromide perovskite single crystals to environmental gases. Sci. Adv. 2, e1600534 (2016).

    Article  ADS  Google Scholar 

  27. Galisteo-López, J. F., Anaya, M., Calvo, M. E. & Míguez, H. Environmental effects on the photophysics of organic–inorganic halide perovskites. J. Phys. Chem. Lett. 6, 2200–2205 (2015).

    Article  Google Scholar 

  28. Tian, Y. et al. Mechanistic insights into perovskite photoluminescence enhancement: light curing with oxygen can boost yield thousandfold. Phys. Chem. Chem. Phys. 17, 24978–24987 (2015).

    Article  Google Scholar 

  29. Meggiolaro, D., Mosconi, E. & De Angelis, F. Mechanism of reversible trap passivation by molecular oxygen in lead–halide perovskites. ACS Energy Lett. 2, 2794–2798 (2017).

    Article  Google Scholar 

  30. Quitsch, W.-A. et al. The role of excitation energy in photobrightening and photodegradation of halide perovskite thin films. J. Phys. Chem. Lett. 9, 2062–2069 (2018).

    Article  Google Scholar 

  31. Leijtens, T. et al. Carrier trapping and recombination: the role of defect physics in enhancing the open circuit voltage of metal halide perovskite solar cells. Energy Environ. Sci. 9, 3472–3481 (2016).

    Article  Google Scholar 

  32. Miyata, K. et al. Large polarons in lead halide perovskites. Sci. Adv. 3, e1701217 (2017).

    Article  Google Scholar 

  33. Tsai, H. et al. Light-induced lattice expansion leads to high-efficiency perovskite solar cells. Science 360, 67–70 (2018).

    Article  ADS  Google Scholar 

  34. Azpiroz, J. M., Mosconi, E., Bisquert, J. & De Angelis, F. Defect migration in methylammonium lead iodide and its role in perovskite solar cell operation. Energy Environ. Sci. 8, 2118–2127 (2015).

    Article  Google Scholar 

  35. Gottesman, R. et al. Extremely slow photoconductivity response of CH3NH3PbI3 perovskites suggesting structural changes under working conditions. J. Phys. Chem. Lett. 5, 2662–2669 (2014).

    Article  Google Scholar 

  36. Barker, A. J. et al. Defect-assisted photoinduced halide segregation in mixed-halide perovskite thin films. ACS Energy Lett. 2, 1416–1424 (2017).

    Article  Google Scholar 

  37. Brennan, M. C., Draguta, S., Kamat, P. V. & Kuno, M. Light-induced anion phase segregation in mixed halide perovskites. ACS Energy Lett. 3, 204–213 (2018).

    Article  Google Scholar 

  38. Yoon, S. J., Kuno, M. & Kamat, P. V. Shift happens. How halide ion defects influence photoinduced segregation in mixed halide perovskites. ACS Energy Lett. 2, 1507–1514 (2017).

    Article  Google Scholar 

  39. Eames, C. et al. Ionic transport in hybrid lead iodide perovskite solar cells. Nat. Commun. 6, 7497 (2015).

    Article  ADS  Google Scholar 

  40. Meggiolaro, D., Mosconi, E. & De Angelis, F. Modeling the interaction of molecular iodine with MAPbI3 : a probe of lead–halide perovskites defect chemistry. ACS Energy Lett. 3, 447–451 (2018).

    Article  Google Scholar 

  41. Boschloo, G. & Hagfeldt, A. Characteristics of the iodide/triiodide redox mediator in dye-sensitized solar cells. Acc. Chem. Res. 42, 1819–1826 (2009).

    Article  Google Scholar 

  42. Zhang, L. & Sit, P. H.-L. Ab initio study of the role of oxygen and excess electrons in the degradation of CH3NH3PbI3. J. Mater. Chem. A 5, 9042–9049 (2017).

    Article  Google Scholar 

  43. Wang, S., Jiang, Y., Juarez-Perez, E. J., Ono, L. K. & Qi, Y. Accelerated degradation of methylammonium lead iodide perovskites induced by exposure to iodine vapour. Nat. Energy 2, 16195 (2016).

    Article  ADS  Google Scholar 

  44. Sadoughi, G. et al. Observation and mediation of the presence of metallic lead in organic–inorganic perovskite films. ACS Appl. Mater. Interfaces 7, 13440–13444 (2015).

    Article  Google Scholar 

  45. Noel, N. K. et al. Enhanced photoluminescence and solar cell performance via Lewis base passivation of organic–inorganic lead halide perovskites. ACS Nano 8, 9815–9821 (2014).

    Article  Google Scholar 

  46. Ling, Y. et al. Enhanced optical and electrical properties of polymer-assisted all-inorganic perovskites for light-emitting diodes. Adv. Mater. 28, 8983–8989 (2016).

    Article  Google Scholar 

  47. Wang, Z. et al. Efficient and stable pure green all-inorganic perovskite CsPbBr3 light-emitting diodes with a solution-processed NiOx interlayer. J. Phys. Chem. C 121, 28132–28138 (2017).

    Article  Google Scholar 

  48. Kim, M., Motti, S. G., Sorrentino, R. & Petrozza, A. Enhanced solar cell stability by hygroscopic polymer passivation of metal halide perovskite thin film. Energy Environ. Sci. 11, 2609–2619 (2018).

    Article  Google Scholar 

  49. Xu, J. et al. Perovskite–fullerene hybrid materials suppress hysteresis in planar diodes. Nat. Commun. 6, 7081 (2015).

    Article  ADS  Google Scholar 

  50. Shao, Y., Xiao, Z., Bi, C., Yuan, Y. & Huang, J. Origin and elimination of photocurrent hysteresis by fullerene passivation in CH3NH3PbI3 planar heterojunction solar cells. Nat. Commun. 5, 5784 (2014).

    Article  ADS  Google Scholar 

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

    Article  ADS  Google Scholar 

  52. Xiao, M. et al. A fast deposition–crystallization procedure for highly efficient lead iodide perovskite thin-film solar cells. Angew. Chem. Int. Ed. 126, 10056–10061 (2014).

    Article  Google Scholar 

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Acknowledgements

This work has been funded by the European Union project PERT PV under grant no. 763977, ERC project SOPHY under grant no. 771528 and PERSEO ‘PERrovskite-based solar cells: towards high efficiency and long-term stability’ (Bando PRIN 2015—Italian Ministry of University and Scientific Research (MIUR) Decreto Direttoriale 4 Novembre 2015 no. 2488, project no. 20155LECAJ). The Ministero Istruzione dell’Università e della Ricerca (MIUR) and the University of Perugia are acknowledged for the financial support through the program “Dipartimenti di Eccellenza 2018-2022” (Grant AMIS) to F.D.A. S.G.M. thanks the CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico—Brasil) for a scholarship (206502/2014-1). M.K. acknowledges funding from the European Union’s Horizon 2020 research and innovation programme under Marie Skłodowska-Curie grant no. 797546 of the FASTEST project. The authors thank G. Paternò for his support in setting up the transient Voc characterization.

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S.G.M. performed the photoluminescence measurements. D.M. and E.M. performed the first-principles calculations. C.A.R.P., J.M.B., M.G. and M.K. were responsible for fabrication of the thin films. M.K. fabricated the solar cell devices and M.K and A.J.B. characterized the solar cell. A.P., S.G.M., A.J.B., D.M. and F.D.A. analysed the data. S.G.M., F.D.A. and A.P. wrote the first draft of the manuscript and all authors contributed to the discussions and finalized the manuscript. A.P. supervised the project.

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Correspondence to Filippo De Angelis or Annamaria Petrozza.

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Motti, S.G., Meggiolaro, D., Barker, A.J. et al. Controlling competing photochemical reactions stabilizes perovskite solar cells. Nat. Photonics 13, 532–539 (2019). https://doi.org/10.1038/s41566-019-0435-1

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