Nano Lett.: Tailored Phase Transformation of CsPbI2Br Films by Copper(II) Bromide for High-Performance All-Inorganic Perovskite Solar Cells

Title：

Tailored Phase Transformation of CsPbI2Br Films by Copper(II) Bromide for High-Performance All-Inorganic Perovskite Solar Cells

Authors：

Kai-Li Wang¹, Rui Wang¹, Zhao-Kui Wang^1,2, *, Meng Li¹, Yue Zhang¹, Heng Ma³, Liang-Sheng Liao^1, *, Yang Yang^2, *

Institutions：

¹Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Jiangsu   Key Laboratory for Carbon-Based Functional Materials and Devices, Suzhou, Jiangsu 215123, China
²Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, United States §

³College of Physics and Electronic Engineering, Henan Normal University, Xinxiang   453007, P.R. China

Abstract：

All-inorganic-based perovskites achieved by replacing the organic component with cesium (Cs) have drawn more attention because of their intrinsic inorganic stability. However, the cell efficiency in all-inorganic perovskite solar cells is still far below that in organic-inorganic hybrid perovskite-based devices. Here, we develop a new strategy to mediate the CsPbI2Br crystallization by directly  doping copper(II) bromide (CuBr2) into a perovskite precursor. The incorporation of CuBr2 played a role in retarding the crystallization dynamics process of CsPbI2Br film, resulting in a high-quality all-inorganic perovskite film with enlarged grain size, improved carrier mobilities, and reduced trap states. The fabricated perovskite solar cells delivered a champion power conversion efficiency of 16.15%, which is the highest efficiency in CsPbI2Br based all-inorganic perovskite solar cells and largely higher than 13.24% for pristine CsPbI2Br based device. The developed doping method paves a new route to fabricate high-performance all-inorganic perovskite solar cells.

IF：

12.08

Link：

https://pubs.acs.org/doi/abs/10.1021/acs.nanolett.9b01553

Editor: Wenchang Zhu