γ-Ray-Induced Degradation in the Triple-Cation Perovskite Solar Cells

Aleksandra G Boldyreva; Azat F Akbulatov; Sergey A Tsarev; Sergey Yu Luchkin; Ivan S Zhidkov; Erst Z Kurmaev; Keith J Stevenson; Vladimir G Petrov; Pavel A Troshin

doi:10.1021/acs.jpclett.8b03222

γ-Ray-Induced Degradation in the Triple-Cation Perovskite Solar Cells

J Phys Chem Lett. 2019 Feb 21;10(4):813-818. doi: 10.1021/acs.jpclett.8b03222. Epub 2019 Feb 8.

Authors

Affiliations

¹ Skolkovo Institute of Science and Technology , Nobel Street 3 , Moscow 143026 , Russia.
² Institute for Problems of Chemical Physics of the Russian Academy of Sciences (ICP RAS) , Semenov Prospect 1 , Chernogolovka 142432 , Russia.
³ Institute of Physics and Technology , Ural Federal University , Mira 9 Str. , Yekaterinburg 620002 , Russia.
⁴ M.N. Mikheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences , S. Kovalevskoi 18 Str. , Yekaterinburg 620108 , Russia.
⁵ Lomonosov Moscow State University , Lelinsky Gory, Moscow 119991 , Russia.

PMID: 30621392
DOI: 10.1021/acs.jpclett.8b03222

Abstract

We report on the impact of γ radiation (0-500 Gy) on triple-cation Cs_0.15MA_0.10FA_0.75Pb(Br_0.17I_0.83)₃ perovskite solar cells. A set of experiments was designed to reveal the individual contributions of the hole-collecting bottom electrode, perovskite absorber, and electron transport layer (ETL) to the overall solar cell degradation under radiation exposure. We show that the glass/ITO/PEDOT:PSS hole-collecting electrode withstands a 500 Gy dose without any losses in the solar cell performance. In contrast, the perovskite absorber films and PC₆₁BM ETL are very sensitive to γ rays, as can be concluded from the radiation-induced decay of the solar cell efficiency by ∼32-41%. Red shift of the perovskite emission bands and strong enhancement of the photoluminescence suggest that γ rays induce phase segregation of iodine-rich and bromine-rich domains, which represents the first reported example of the radiation-induced halide phase separation in perovskite films. The degradation pathway revealed here emphasizes the need for developing a new generation of metal halide absorbers and ETL materials with improved radiation stability to enable potential space applications of perovskite photovoltaics.