Ion Migration Accelerated Reaction between Oxygen and Metal Halide Perovskites in Light and Its Suppression by Cesium Incorporation. Issue 8 (15th January 2021)

• Record Type: Journal Article
• Authors: Lin, Dongxu; Shi, Tingting; Xie, Haipeng; Wan, Fang; Ren, Xiaoxue; Liu, Kai; Zhao, Yuan; Ke, Lili; Lin, Yun; Gao, Yongli; Xu, Xin; Xie, Weiguang; Liu, Pengyi; Yuan, Yongbo
• Is Part Of: Advanced energy materials. Volume 11:Issue 8(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-01-15
• Subjects: composition engineering -- ion migration -- oxide stability -- perovskite solar cells -- superoxide; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202002552
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Organic‐inorganic hybrid perovskite solar cells are susceptible to multiple influencing factors such as moisture, oxygen, heat stress, ion migration. Given the complex practical working conditions for solar cells, a fundamental question is how different failure mechanisms collaborate and substantially accelerate the device degradation. In this study, it is found that ion migration can accelerate the reaction between oxygen and methylammonium lead iodide perovskite in light conditions. This is suggested since regions with local electric fields suffer from more severe decomposition. Here it is reported that cesium ions (Cs + ) incorporated in perovskite lattice, with a moderate doping concentration (e.g. 5%), can function as stabilizers to efficiently interrupt such a synergistic effect between oxygen induced degradation and ion migration while retaining the high performance of perovskite solar cells. Both experimental and theoretical results suggest that 5% Cs + ions incorporation simultaneously suppresses the formation of reactive superoxide ions ( O 2 − ) as well as ion migration in perovskites by forming additional energy barriers. This A‐site cations engineering is also a promising strategy to circumvent the detrimental effect of oxygen molecules in FA‐based perovskites, which is important for developing high‐efficiency perovskite solar cells with enhanced stability. Abstract : The synergistic effect between oxygen‐photon‐induced decay and ion migration in accelerating the decomposition of perovskite materials is unveiled. A simple but efficient method, Cs + ion doping, can simultaneously reduce the O 2 − ion generation and suppress ion migration to block such degradation. This work opens up new insights in designing efficient perovskite solar cells with long‐term stability.