Elucidating the hysteresis effect in printed flexible perovskite solar cells with SnO quantum dot- and PCBM-based electron transport layers.

Recently, flexible perovskite solar cells (FPSCs) fabricated using solution-processed printing techniques have garnered significant attention. However, challenges remain in achieving cost-effective, scalable manufacturing under ambient conditions and ensuring stable, efficient devices. This study focuses on fabricating printed FPSCs using the slot-die coating technique and examines the impact of SnO quantum dot (QD) and (6,6)-Phenyl C61 butyric acid methyl ester (PCBM) based electron transport layers (ETLs) on device performance and hysteresis. Experimentally results show that SnO QD-based devices exhibited favorable photovoltaic properties but significant hysteresis compared to PCBM-based devices. Numerical simulations have shown that the hysteresis effect in devices is influenced not only by the higher concentration of mobile ions in the perovskite layer of PCBM-based devices compared to SnO QD-based devices, but also by the more effective redistribution of these ions during forward and reverse scans. The results provide insights into the behavior of printed FPSCs with different ETLs, contributing to the development of high-performance, hysteresis-free printed FPSCs.