High‐Temperature Perovskite Solar Cells

Herein, high‐temperature (over 200 °C) perovskite solar cells (PSCs) are fabricated and studied for the first time. Inorganic CsPbI 2 Br 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), CsPbI 2 Br devices show superior V OC and FF temperature coefficients but inferior J SC temperature coefficients. As a result, PCE temperature coefficients of CsPbI 2 Br 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.