Low-Temperature robust MAPbI3 perovskite solar cells with power conversion efficiency exceeding 22.4%

Hybrid halide perovskite solar cells (PSCs) have enormous potential to provide energy for future space explo-ration and aerospace due to their unique advantages in harsh environments. Unfortunately, it is challenging to fabricate robust PSCs that are insensitive to low temperatures. This study presented the performance evolution of methylammonium triiodide (MAPbI3) PSCs across a temperature range of 290 to 90 K and highlighted the decisive impact of interfacial defects on the devices' low-temperature performance. The introduction of poly-methyl methacrylate (PMMA) as interface modification layer, efficiently passivated the interface defects, released the interfacial stress, and thus decreased the phase transition temperature. As a result, the PMMA-modified device achieved a maximum efficiency of 22.4% at 90 K which was one of the highest efficiencies reported for MA-based PSCs at low temperatures. Remarkably, the PMMA-modified device retained nearly 100% of initial efficiency after 26 temperature cycling tests between 290 and 90 K, whereas the control device maintained only 62% of initial efficiency. This work demonstrated that interface engineering is a promising strategy for improving the low-temperature performance of PSCs.