Article

Accelerated degradation of methylammonium lead iodide perovskites induced by exposure to iodine vapour

  • Nature Energy 2, Article number: 16195 (2016)
  • doi:10.1038/nenergy.2016.195
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Abstract

Efficiencies of organic–inorganic lead halide perovskite solar cells (PSCs) have significantly increased in recent years, but instability issues impede their further development and application. Previous studies reported that volatile species (for example, iodine, I2) were generated when perovskites were subjected to moisture, oxygen, light illumination, applied electric field, and thermal stress (all of which are relevant to the operation of PSCs in practical applications). Here we show that I2 vapour causes severe degradation of MAPbI3 (MA: CH3NH3+) perovskite, due to chemical chain reactions. Furthermore, I2 vapour could also induce degradation of other iodide-based perovskites, such as FAPbI3 (FA: HC(NH2)2+) and FA0.8Cs0.2PbI3. The results reveal a universal degradation factor for iodide-based perovskite by I2. As the release of I2 is nearly inevitable during practical applications, this work suggests that MAPbI3 may not be suitable for long-term stable solar cells and it is imperative to develop other types of perovskite material to achieve stable PSCs.

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Change history

  • Corrected online 14 July 2017

    In the PDF version of this article previously published, the year of publication provided in the footer of each page and in the 'How to cite' section was erroneously given as 2017, it should have been 2016. This error has now been corrected. The HTML version of the article was not affected.

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Acknowledgements

This work was supported by funding from the Energy Materials and Surface Sciences Unit of the Okinawa Institute of Science and Technology Graduate University, the OIST R&D Cluster Research Program and JSPS KAKENHI Grant Number 15K17925. We thank S. D. Aird, the Technical Editor at Okinawa Institute of Science and Technology Graduate University (OIST), for valuable suggestions in revising the manuscript.

Author information

Author notes

    • Shenghao Wang

    Present address: Institute of Applied Physics, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8573, Japan.

Affiliations

  1. Energy Materials and Surface Sciences Unit (EMSS), Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan

    • Shenghao Wang
    • , Yan Jiang
    • , Emilio J. Juarez-Perez
    • , Luis K. Ono
    •  & Yabing Qi

Authors

  1. Search for Shenghao Wang in:

  2. Search for Yan Jiang in:

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Contributions

Y.B.Q. conceived the idea, designed the experiments and supervised the project. S.W. prepared vacuum-processed MAPbI3 samples. Y.J. and S.W. prepared solution-processed perovskite films. S.W. performed most of the characterizations. Y.J. measured scanning electron microscopy images. E.J.J.-P. performed theoretical calculations. All authors discussed the results, wrote the manuscript and revised it.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Yabing Qi.

Supplementary information

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    Supplementary Information

    Supplementary Figures 1–26, Supplementary References.