Understanding the relationship between ion migration and the anomalous hysteresis in high-efficiency perovskite solar cells: A fresh perspective from halide substitution

Ion migration has recently piqued intensive attention with respect to the emerging perovskite solar cells (PSCs), but exactly how it impacts on cell performance is still elusive. In this paper, we validate a simple model to relate the scan rate-dependent hysteresis of the solar cells and the defect assisted ion migration in perovskite materials by means of halide substitution to form MAPbBrxI3−x (x~0–0.6), prepared by a modified two-step method...