Methylamine Gas Treatment Affords Improving Semitransparency, Efficiency, and Stability of CH ₃ NH ₃ PbBr ₃ ?Based Perovskite Solar Cells

High bandgap semitransparent solar cells based on CH3NH3PbBr3 perovskites are attractive for building integration, tandem cells, and electrochemical applications. The lack of control the perovskite growth limit exploitation CH3NH3PbBr3-based cells. Herein, a post-treatment is carried out after initial crystallization methylamine gas that drastically enhances quality leading to highly crystalline film with improved average visible transmittance (AVT) close 56%. Opaque devices showed outstanding results in terms open-circuit voltage power conversion efficiency (PCE) reaching 1.54 V 9.2%, respectively. These achievements ascribed reduced morphological defects better interface nonradiative pathways. For first time, fabrication demonstrated maximum PCE equal 7.6%, an AVT full stack device 52%, excellent light stability at maximum-power point tracking.