Surface passivation of perovskite film for efficient solar cells

• Published in: Nature photonics 2019-07, Vol.13 (7), p.460-466
• Main Authors: Jiang, Qi, Zhao, Yang, Zhang, Xingwang, Yang, Xiaolei, Chen, Yong, Chu, Zema, Ye, Qiufeng, Li, Xingxing, Yin, Zhigang, You, Jingbi
• Format: Article
• Language: English
• Subjects: 639/301/1019/1020; 639/301/299/946; Applied and Technical Physics; Efficiency; Energy conversion efficiency; Iodides; Open circuit voltage; Passivity; Perovskites; Photovoltaic cells; Physics; Physics and Astronomy; Quantum Physics; Radiative recombination; Recombination; Solar cells; Surface defects
• ISSN: 1749-4885; 1749-4893
• DOI: 10.1038/s41566-019-0398-2

In recent years, the power conversion efficiency of perovskite solar cells has increased to reach over 20%. Finding an effective means of defect passivation is thought to be a promising route for bringing further increases in the power conversion efficiency and the open-circuit voltage ( V OC ) of perovskite solar cells. Here, we report the use of an organic halide salt phenethylammonium iodide (PEAI) on HC(NH 2 ) 2 –CH 3 NH 3 mixed perovskite films for surface defect passivation. We find that PEAI can form on the perovskite surface and results in higher-efficiency cells by reducing the defects and suppressing non-radiative recombination. As a result, planar perovskite solar cells with a certificated efficiency of 23.32% (quasi-steady state) are obtained. In addition, a V OC as high as 1.18 V is achieved at the absorption threshold of 1.53 eV, which is 94.4% of the Shockley–Queisser limit V OC (1.25 V). Planar perovskite solar cells that have been passivated using the organic halide salt phenethylammonium iodide are shown to have suppressed non-radiative recombination and operate with a certified power conversion efficiency of 23.3%.