MAPbCI3-Mediated Decomposition Process to Tune Cl/Pbl2 Distribution in MAPbl3 Films

Various methods have been developed to optimize the active layer of perovskite solar cells. To date, the introduction of excess PM, and chlorine doping are two typical means. Herein, an ion exchange decomposition process was designed to combine these two approaches. In this process, the I-Cl exchange and MACI sublimation occurred simultaneously at elevated temperature, resulting in a Pbl(2)-excess, Cl-doped perovskite film. This combined strategy could guarantee that as much chlorine as possible was doped into the perovskite crystal lattice, which enables the production of perovskite films with obviously reduced defect density and enhanced carrier diffusion length. Strikingly, the power conversion efficiency of the device is boosted from 17.17% to 20.15%.