Intermediate-Phase-Mediated Crystallization and A-Site Doping in CsPbI2Br Perovskite Solar Cells Enabled by Dimethylammonium Iodide.
CsPbI2Br perovskites are promising wide-bandgap absorbers for tandem photovoltaics but are limited by unfavorable film crystallization and high defect densities. Herein, dimethylammonium iodide is introduced as a multifunctional agent to simultaneously regulate crystallization dynamics and modulate A-site composition....