Exploring π-extended subporphyrinoids as electron transporting materials in perovskite solar cells

Due to their strong acceptor properties and enhanced charge transport capabilities, non-fullerene electron acceptors based on [Formula: see text]-extended derivatives – subnaphthalocyanines (SubNc) or subphtalocyanine dimers (SubPc[Formula: see text] – have been employed in organic photovoltaics in the past as an alternative to the expensive fullerene. However, these promising [Formula: see text]-extended derivatives have not been explored in perovskite solar cell technology. In this work, we implement a vacuum-deposited very thin film of SubNc or SubPc 2 as electron transport layers in perovskite solar cells. In particular, we demonstrate the excellent electron extraction properties of the thin films in contact with perovskite layer. The fabricated perovskite solar cells exhibit enhanced device performances with reduced hysteresis index and improved device stability. Our results validate the use of [Formula: see text]-extended subporphyrinoids as promising candidates for perovskite optoelectronics with enhanced stability properties, being essential for further commercialization of the perovskite technology.