Niobium pentoxide-mediated engineering of the SnO₂/perovskite interface: simulation study

Planar perovskite solar cells suffer from interfacial losses at the perovskite/charge transport layer junction, limiting their efficiency and stability. This work introduces an ultrathin niobium pentoxide layer between the electron transport layer and perovskite interface, acting as an interlayer. The niobium pentoxide interface enables charge transport across the interlayer in the solar cells without causing any significant changes in the characteristics of the perovskite absorber. This modification suppressed leakage current and charge carrier recombination, decreasing the energy barrier for electron extraction, leading to improved open-circuit voltage and overall power conversion efficiency. The method achieved a maximum efficiency of 25.19% in single-junction typical perovskite solar cells in comparison to the 22.66% for the optimized device without modification. Moreover, increasing operating temperature from 300 K to 400 K reduced the normalized efficiency of the solar cell only by 14% of its initial performance at 300 K, indicating a low reduction in electrical device properties. This study offers insights into engineering the interface properties and improving the photovoltaic performance of perovskite photovoltaics.