Double-anchored dipole buried interface enabling high-performance perovskite solar cells

Abstract

A robust buried interface between electron transport layer (ETL) and perovskite active layer (PVK) is essential for achieving high-performance perovskite solar cells (PSCs). Energy level mismatches and poor interfacial contact hinder both efficiency and stability. In this study, we introduce 6-(trifluoromethyl)pyridine-3-amidine hydrochloride (TFPCl) to establish a dipole interface. The introduction of TFPCl not only optimizes the energy levels through its dipole characteristics, facilitating the extraction and transportation of carriers, but also reinforces the interfacial contact between ETL and PVK through dual anchoring, thereby enhancing stability. The improved perovskite quality and effective passivation of defects in SnO₂ and perovskite optimized the device's photovoltaic performance. Consequently, the TFPCl-modulated PSC achieves a power conversion efficiency (PCE) of 25.10 % and demonstrates environmental storage stability of 1500 h. This study demonstrates a simple yet effective approach for enhancing the photovoltaic performance and stability of PSCs by introducing a dipole molecule into the ETL/PVK buried interface.