Optimal interfacial engineering with different bifunctional alkylamine sulfonates for efficient perovskite solar cells

Abstract

Perovskite solar cells have gradually become the most attractive alternative for next-generation photovoltaic devices due to their excellent photovoltaic conversion efficiencies and low manufacturing costs. Defect engineering is an essential topic for improving the performance of perovskite devices. In this study, we utilize a bifunctional alkylamine sulfonate to modify the perovskite interfaces. The TsO− of sulfonates coordinates with Pb2+, while –NH2 of alkylamine forms hydrogen bonds with iodine, which reduces charge recombination and improves energy level arrangement. The molecular size and the alkylamine's dielectric constant significantly influence the interface modification performance. For the champion device with BATsO treatment, there is an enhancement in both the fill factor and the open-circuit voltage, resulting in a power conversion efficiency (PCE) of 23.53%. After 400 h of working condition, the device maintains roughly 90.40% of its initial efficiency. Therefore, this study postulates that modifying bifunctional alkylamine sulfonates could effectively enhance the PSC's performance.