LAUSR

Perovskite solar cells (PSCs) are displaying auspicious candidacy towards photovoltaic technology based on their features including low-cost assembling, exceptional performance, and low-temperature solution processing. However, the progression of PSCs in the direction of commercialized upgrade desires high efficiency and long-term stability. The surface and grain boundaries of perovskite layer, as well as interfaces are critical factors intended for the performance of the assembled cells. The defects mainly located in the perovskite surfaces can trigger the hysteresis, carrier recombination, and degradation, which obstacle the progress in the power conversion efficiency (PCE) of the ensuing cells. Herein, we propose to stabilize the α-FAPbI 3 perovskite phase without scarifying the spectral features by taking the benefits of 2,3,4,5,6-pentafluorobenzyl phosphonic acid (PFBPA) molecule as a passivation agent for the first time. Accordingly, high-quality PSCs with improved efficiency of 22.25% was attained with respectable cell parameters compared to the pristine cells without passivation layer. Remarkably, the PFBPA passivated ultrathin layer effectually prevents the perovskite layer from moisture, resulting in better long-term stability for unsealed PSCs maintain >90% of the original efficiency under different humidity levels (40 to 75%) after 600 h. This work finds out that the PFBPA passivation has a considerable impact in obtaining high-quality and stable FAPbI 3 films for extra beneficent both the efficiency and stability of PSCs.