Influence of phase transition on stability of perovskite solar cells under thermal cycling conditions

In this research, we investigated the influence of phase transition in four standard perovskite materials on the device stability under thermal cycling (TC) condition, which is listed in International Electrotechnical Commission (IEC) stability tests criteria. The evolution of morphology, phase structure and charge carrier dynamics of four type perovskite materials throughout thermal cycling were analyzed. It was found that the cubic to tetragonal phase transition of MAPbI 3 caused the quick degradation of the device, the α to δ phase transition in FAPbI 3 and FA 0.6 MA 0.4 PbI 3 resulted in sustained efficiency loss, while the FA 0.9 Cs 0.1 PbI 3 was more stable compared to above three perovskites under the same test condition. The FA 0.9 Cs 0.1 PbI 3 device retained nearly 88% of its initial efficiency after 200 temperature cycles between −30 °C and 85 °C, which could be ascribed to its successful stabilization of perovskite structure.