Skip to main content

Thank you for visiting 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.

Tailored interfaces of unencapsulated perovskite solar cells for >1,000 hour operational stability


Long-term device stability is the most pressing issue that impedes perovskite solar cell commercialization, given the achieved 22.7% efficiency. The perovskite absorber material itself has been heavily scrutinized for being prone to degradation by water, oxygen and ultraviolet light. To date, most reports characterize device stability in the absence of these extrinsic factors. Here we show that, even under the combined stresses of light (including ultraviolet light), oxygen and moisture, perovskite solar cells can retain 94% of peak efficiency despite 1,000 hours of continuous unencapsulated operation in ambient air conditions (relative humidity of 10–20%). Each interface and contact layer throughout the device stack plays an important role in the overall stability which, when appropriately modified, yields devices in which both the initial rapid decay (often termed burn-in) and the gradual slower decay are suppressed. This extensively modified device architecture and the understanding developed will lead towards durable long-term device performance.

This is a preview of subscription content

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Fig. 1: Champion FAMAs device characterization.
Fig. 2: Operational stability of TiO2/FAMACs/HTM/Au devices in ambient conditions.
Fig. 3: ToF–SIMS profiling of operated devices.
Fig. 4: Operational stability of ETL/FAMACs/EH44/MoO x /Al devices in ambient.


  1. 1.

    Lee, M. M., Teuscher, 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  Google Scholar 

  2. 2.

    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  Google Scholar 

  3. 3.

    Manser, J. S., Christians, J. A. & Kamat, P. V. Intriguing optoelectronic properties of metal halide perovskites. Chem. Rev. 116, 12956–13008 (2016).

    Article  Google Scholar 

  4. 4.

    Best Research Cell Efficiences (NREL, 2017);

  5. 5.

    Manser, J. S., Saidaminov, M. I., Christians, J. A., Bakr, O. M. & Kamat, P. V. Making and breaking of lead halide perovskites. Acc. Chem. Res. 49, 330–338 (2016).

    Article  Google Scholar 

  6. 6.

    Habisreutinger, S. N., McMeekin, D. P., Snaith, H. J. & Nicholas, R. J. Research update: strategies for improving the stability of perovskite solar cells. APL Mater. 4, 91503 (2016).

    Article  Google Scholar 

  7. 7.

    Tan, H. et al. Efficient and stable solution-processed planar perovskite solar cells via contact passivation. Science 355, 722–726 (2017).

    Article  Google Scholar 

  8. 8.

    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 

  9. 9.

    Shin, S. S. et al. Colloidally prepared La-doped BaSnO3 electrodes for efficient, photostable perovskite solar cells. Science 356, 167–171 (2017).

    Article  Google Scholar 

  10. 10.

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

    Article  Google Scholar 

  11. 11.

    Dualeh, A., Gao, P., Seok, S. Il, Nazeeruddin, M. K. & Grätzel, M. Thermal behavior of methylammonium lead-trihalide perovskite photovoltaic light harvesters. Chem. Mater. 26, 6160–6164 (2014).

    Article  Google Scholar 

  12. 12.

    Nenon, D. et al. Structural and chemical evolution of methylammonium lead halide perovskites during thermal processing from solution. Energy Environ. Sci. 9, 2072–2082 (2016).

    Article  Google Scholar 

  13. 13.

    Conings, B. et al. Intrinsic thermal instability of methylammonium lead trihalide perovskite. Adv. Energy Mater. 5, 1500477 (2015).

    Article  Google Scholar 

  14. 14.

    Christians, J. A., Miranda Herrera, P. A. & Kamat, P. V. Transformation of the excited state and photovoltaic efficiency of CH3NH3PbI3 perovskite upon controlled exposure to humidified air. J. Am. Chem. Soc. 137, 1530–1538 (2015).

    Article  Google Scholar 

  15. 15.

    Yang, J., Siempelkamp, B. D., Liu, D. & Kelly, T. L. An investigation of CH3NH3PbI3 degradation rates and mechanisms in controlled humidity environments using in situ techniques. ACS Nano 9, 1955–1963 (2015).

    Article  Google Scholar 

  16. 16.

    Aristidou, N. et al. Fast oxygen diffusion and iodide defects mediate oxygen-induced degradation of perovskite solar cells. Nat. Commun. 8, 15218 (2017).

    Article  Google Scholar 

  17. 17.

    Hoye, R. L. Z. et al. Perovskite-inspired photovoltaic materials: toward best practices in materials characterization and calculations. Chem. Mater. 29, 1964–1988 (2017).

    Article  Google Scholar 

  18. 18.

    Steirer, K. X. et al. Defect tolerance in methylammonium lead triiodide perovskite. ACS Energy Lett. 1, 360–366 (2016).

    Article  Google Scholar 

  19. 19.

    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  Google Scholar 

  20. 20.

    Sutton, R. J. et al. Bandgap-tunable cesium lead halide perovskites with high thermal stability for efficient solar cells. Adv. Energy Mater. 6, 1502458 (2016).

    Article  Google Scholar 

  21. 21.

    Swarnkar, A. et al. Quantum dot-induced phase stabilization of α-CsPbI3 perovskite for high-efficiency photovoltaics. Science 354, 92–95 (2016).

    Article  Google Scholar 

  22. 22.

    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 

  23. 23.

    Wang, Z. et al. Efficient ambient-air-stable solar cells with 2D–3D heterostructured butylammonium-caesium-formamidinium lead halide perovskites. Nat. Energy 6, 17135 (2017).

    Article  Google Scholar 

  24. 24.

    Manspeaker, C., Venkatesan, S., Zakhidov, A. & Martirosyan, K. S. Role of interface in stability of perovskite solar cells. Curr. Opin. Chem. Eng. 15, 1–7 (2017).

    Article  Google Scholar 

  25. 25.

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

    Article  Google Scholar 

  26. 26.

    Zhao, L. et al. Redox chemistry dominates the degradation and decomposition of metal halide perovskite optoelectronic devices. ACS Energy Lett. 1, 595–602 (2016).

    Article  Google Scholar 

  27. 27.

    Li, Z. et al. Extrinsic ion migration in perovskite solar cells. Energy Environ. Sci. 10, 1234–1242 (2017).

    Article  Google Scholar 

  28. 28.

    Dawson, J. A. et al. Mechanisms of lithium intercalation and conversion processes in organic–inorganic halide perovskites. ACS Energy Lett. 2, 1818–1824 (2017).

    Article  Google Scholar 

  29. 29.

    Habisreutinger, S. N. et al. Carbon nanotube/polymer composite as a highly stable charge collection layer in perovskite solar cells. Nano Lett. 14, 5561–5568 (2014).

    Article  Google Scholar 

  30. 30.

    Leijtens, T. et al. Hydrophobic organic hole transporters for improved moisture resistance in metal halide perovskite solar cells. Appl. Mater. Interfaces 8, 5981–5989 (2016).

    Article  Google Scholar 

  31. 31.

    Nguyen, W. H., Bailie, C. D., Unger, E. L. & McGehee, M. D. Enhancing the hole-conductivity of spiro-OMeTAD without oxygen or lithium salts by using spiro(TFSI)2 in perovskite and dye-sensitized solar cells. J. Am. Chem. Soc. 136, 10996–11001 (2014).

    Article  Google Scholar 

  32. 32.

    Habisreutinger, S. N., Noel, N. K., Snaith, H. J. & Nicholas, R. J. Investigating the role of 4-tert-butylpyridine in perovskite solar cells. Adv. Energy Mater. 7, 1601079 (2016).

    Article  Google Scholar 

  33. 33.

    Reese, M. O. et al. Consensus stability testing protocols for organic photovoltaic materials and devices. Sol. Energy Mater. Sol. Cells 95, 1253–1267 (2011).

    Article  Google Scholar 

  34. 34.

    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 

  35. 35.

    Leijtens, T. et al. Overcoming ultraviolet light instability of sensitized TiO2 with meso-superstructured organometal tri-halide perovskite solar cells. Nat. Commun. 4, 2885 (2013).

    Article  Google Scholar 

  36. 36.

    Ahn, N. et al. Trapped charge-driven degradation of perovskite solar cells. Nat. Commun. 7, 13422 (2016).

    Article  Google Scholar 

  37. 37.

    Roose, B. et al. Mesoporous SnO2 electron selective contact enables UV-stable perovskite solar cells. Nano Energy 30, 517–522 (2016).

    Article  Google Scholar 

  38. 38.

    Jiang, Q. et al. Enhanced electron extraction using SnO2 for high-efficiency planar-structure HC(NH2)2PbI3-based perovskite solar cells. Nat. Energy 2, 16177 (2016).

    Article  Google Scholar 

  39. 39.

    Ihly, R. et al. Efficient charge extraction and slow recombination in organic–inorganic perovskites capped with semiconducting single-walled carbon nanotubes. Energy Environ. Sci. 9, 1439–1449 (2016).

    Article  Google Scholar 

  40. 40.

    Domanski, K. et al. Not all that glitters is gold: metal-migration-induced degradation in perovskite solar cells. ACS Nano 10, 6306–6314 (2016).

    Article  Google Scholar 

  41. 41.

    Cacovich, S. et al. Gold and iodine diffusion in large area perovskite solar cells under illumination. Nanoscale 9, 4700–4706 (2017).

    Article  Google Scholar 

  42. 42.

    Schulz, P. et al. High work function molybdenum oxide hole extraction contacts in hybrid organic–inorganic perovskite solar cells. ACS Appl. Mater. Interfaces 8, 31491–31499 (2016).

    Article  Google Scholar 

  43. 43.

    Zhao, Y., Nardes, A. M. & Zhu, K. Effective hole extraction using MoO x –Al contact in perovskite CH3NH3PbI3 solar cells. Appl. Phys. Lett. 104, 213906 (2014).

    Article  Google Scholar 

  44. 44.

    Wojciechowski, K., Saliba, M., Leijtens, T., Abate, A. & Snaith, H. J. Sub-150 °C processed meso-superstructured perovskite solar cells with enhanced efficiency. Energy Environ. Sci. 7, 1142–1147 (2014).

    Article  Google Scholar 

  45. 45.

    Ahn, N. et al. Highly reproducible perovskite solar cells with average efficiency of 18.3% and best efficiency of 19.7% fabricated via Lewis base adduct of lead(ii) iodide. J. Am. Chem. Soc. 137, 8696–8699 (2015).

    Article  Google Scholar 

  46. 46.

    De Souza, R. A. & Martin, M. Probing diffusion kinetics with secondary ion mass spectrometry. MRS. Bull. 34, 907–914 (2009).

    Article  Google Scholar 

  47. 47.

    Stevie, F. A. Secondary Ion Mass Spectrometry: Applications for Depth Profiling and Surface Characterization (Momentum, London, 2015).

    Google Scholar 

  48. 48.

    Wilson, R. G., Stevie, F. A. & Magee, C. W. Secondary Ion Mass Spectrometry: a Practical Handbook for Depth Profiling and Bulk Impurity Analysis (Wiley-Interscience, Hoboken, NJ, 1989).

    Google Scholar 

Download references


This work was supported by the Hybrid Perovskite Solar Cell Program, and B.T.V. was supported by the Organic Photovoltaic Program, which are funded by the US Department of Energy (DOE) under Contract No. DE-AC36-08-GO28308 with the National Renewable Energy Laboratory through the US DOE Solar Energy Technologies Program. J.A.C. was supported by the DOE Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award through the Solar Energy Technologies Office under DOE contract number DE-SC00014664. We thank B. To for the SEM imaging, A. Hicks for assistance with the graphics, and A. Paquin and F. Bélanger of PCAS Canada for supplying 2,7-dibromocarbazole as a precursor for the synthesis of the EH44 HTM used in this study.

Author information




J.A.C, J.M.L. and J.J.B. conceived the project. J.A.C. fabricated the devices and thin-film samples. P.S. designed and performed the photoemission experiments and analysed the data. J.S.T. and T.H.S. synthesized and characterized EH44, and A.S. supervised. J.A.C. and B.J.T.V. performed the stability experiments. S.P.H. performed the ToF–SIMS measurements and S.P.H., J.A.C. and P.S. analysed the ToF–SIMS data. J.M.L. supervised the entire project. J.A.C. wrote the first draft of the paper. All the authors discussed the results and contributed to the writing of the paper.

Corresponding authors

Correspondence to Joseph J. Berry or Joseph M. Luther.

Ethics declarations

Competing interests

The authors declare no competing financial 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 Tables 1–4, Supplementary Figures 1–18

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

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

Download citation

Further reading


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