Evolved photovoltaic performance of MAPbI3 and FAPbI3-based perovskite solar cells in low-temperatures

Organic-inorganic hybrid perovskites have emerged as an up-and-coming contender for photovoltaic devices owing to their exceptional photovoltaic properties. However, current research predominantly concentrates on their performance under ambient conditions at room temperature. In this work, we delve into the novel territory by investigating MAPbI3-based and FAPbI3-based perovskite solar cells (PSCs) in the temperature range of 300 to 150 K. Remarkable efficiency enhancements of nearly 5% and 20% were obtained at 250 and 210 K, respectively. However, further decreasing the temperature impairs the photovoltaic performance. We propose an underlying mechanism influencing the performance change in perovskite devices at low temperatures by examining the temperature-dependent ultraviolet-visible and photoluminescence spectra results. At the beginning of the cooling process, from 300 to 250 K for MAPbI3 and from 300 to 210 K for FAPbI3, the performance enhancement stems primarily from the enhanced open-circuit voltage by the tuned band gap of the perovskite films. Further lowering the temperature would change the perovskite structure, impairing the performance of PSCs. FAPbI3-based PSCs show a better tolerance in low temperatures owing to the more stable perovskite crystal structure. The present findings offer valuable theoretical guidance for preparing outstanding PSCs for low-temperature applications.