Sub-1.4eV bandgap inorganic perovskite solar cells with long-term stability

• DOI: 10.1038/s41467-019-13908-6
• Publication Date: 2020-01-09T11:02:26Z
• Authors: Mingyu Hu; Min Chen; Peijun Guo; Hua Zhou; Junjing Deng; Yudong Yao; Yi Jiang; Jue Gong; Zhenghong Dai; Yunxuan Zhou; Feng Qian; Xiaoyu Chong; Jing Feng; Richard D. Schaller; Kai Zhu; Nitin P. Padture; Yuanyuan Zhou
• Keywords: Science; Q; 01 natural sciences; 7. Clean energy; Article; 0104 chemical sciences

AbstractState-of-the-art halide perovskite solar cells have bandgaps larger than 1.45 eV, which restricts their potential for realizing the Shockley-Queisser limit. Previous search for low-bandgap (1.2 to 1.4 eV) halide perovskites has resulted in several candidates, but all are hybrid organic-inorganic compositions, raising potential concern regarding device stability. Here we show the promise of an inorganic low-bandgap (1.38 eV) CsPb0.6Sn0.4I3 perovskite stabilized via interface functionalization. Device efficiency up to 13.37% is demonstrated. The device shows high operational stability under one-sun-intensity illumination, with T80 and T70 lifetimes of 653 h and 1045 h, respectively (T80 and T70 represent efficiency decays to 80% and 70% of the initial value, respectively), and long-term shelf stability under nitrogen atmosphere. Controlled exposure of the device to ambient atmosphere during a long-term (1000 h) test does not degrade the efficiency. These findings point to a promising direction for achieving low-bandgap perovskite solar cells with high stability.