High‐Temperature Perovskite Solar Cells

Herein, high‐temperature (over 200 °C) perovskite solar cells (PSCs) are fabricated and studied for the first time. Inorganic CsPbI2Br perovskite is used as absorber and carbon nanotubes (CNTs) are directly used as the hole extraction electrode. Such device retains over 80% of its initial power conversion efficiency (PCE) after heating at 200 °C for 45 h, enabling its operation at high temperatures. By recording reverse and forward J–V curves at different temperatures (25–220 °C), temperature coefficients of photovoltaic parameters are obtained. Compared with conventional high‐temperature solar cells (Si, CuInGaSe, and GaAs), CsPbI2Br devices show superior VOC and FF temperature coefficients but inferior JSC temperature coefficients. As a result, PCE temperature coefficients of CsPbI2Br devices are superior over Si and CuInGaSe solar cells, and are comparable with those of GaAs solar cells. Meanwhile, the mitigation of charge accumulation at elevated temperatures results in a gradual decrease in J–V hysteresis. Therefore, this study may expand the application of PSCs into high‐temperature fields, such as space exploration.