Interfacial engineering for high performance perovskite solar cells

Outstanding material properties allowed perovskite solar cells’ power conversion efficiencies (PCEs) exceed 25% within a decade, demonstrating the most rapid increase rate in PCEs among all the existing photovoltaic (PV) technologies. Despite such significant progress perovskite technology commercialization requires further enhancement in device performance. Here, we report a strategy for optimizing interfacial quality of the perovskite solar cells (PSCs). The interfacial layer between the electron transport layer (ETL) and the perovskite absorber were optimized by interface engineering technique via preparing the ETL consisted of Tin(IV) oxide (SnO2) quantum dots (QDs), SnO2 nanoparticle (NP) and a passivation layer based on Poly(methyl methacrylate): [6,6]-phenyl-C61-butyric acid methyl ester (PMMA:PCBM). It was demonstrated that the PSCs with a single-layer ETL made of SnO2 QDs exhibit strong I-V hysteresis, while the application of a triple-layer ETL effectively suppresses the hysteresis due to the optimization of ETL/perovskite interface. This work demonstrated the effective protocol which can substantially improve the performance of PSCs and eliminate the I-V hysteresis.