Highly Efficient and Stable Planar Perovskite Solar Cells with Modulated Diffusion Passivation Toward High Power Conversion Efficiency and Ultrahigh Fill Factor

Modulated Diffusion Passivation In article number 1900293, Jingjing Chang and co‐workers demonstrate a novel solution process to develop 2D/3D perovskites with modulated diffusion passivation by introducing a PEAI and DMF additive, which could effectively enhance device performance and long‐term stability. The solar cells with passivation treatment exhibit a high fill factor of 83.6% and an average power conversion efficiency of 21.4%.