Enhancement of the photovoltaic performance and the stability of perovskite solar cells via the modification of electron transport layers with reduced graphene oxide/polyaniline composite

[Display omitted] •G-PANI modification of ETL boosts the electron transfer process through grain boundaries passivation.•Reasonable photovoltaic performance for G-PANI based perovskite solar cells.•Non-encapsulated G-PANI based devices show excellent long-term ambient stability. The performance of perovskite solar cells (PSCs) may be improved through the incorporation of suitable materials into electron transport layer (ETL). In this study, reduced graphene oxide/polyaniline composite (G-PANI) was introduced into mesoporous TiO2 (mp-TiO2) precursor solution to enhance the performance of triple cation perovskite solar cells (TC-PSCs). As it was observed, the modification of mp-TiO2 could increase the short-circuit current density (Jsc) and the fill factor (FF) parameters of the fabricated devices. So, by employing G-PANI nanocomposite into the mp-TiO2 ETL layer, a champion power conversion efficiency of 16.48% was obtained, 33.7% higher than that of pure mp-TiO2 devices. This occurred through improvements in the crystalline structure, mitigate charge recombination at the TiO2/perovskite interface, reduce charge trapping at the perovskite surface through grain boundaries passivation, and tailor edge absorption of the perovskite films. The proposed approach not only increases the photovoltaic parameters of TC-PSCs but also improves the shelf stability of TC-PSCs. The obtained results prove that G-PANI composite as compared to pristine reduce graphene oxide is a better candidate for modification of mp-TiO2 ETL to boost the performance of PSCs and also stabilize them.