Interfacial engineering of sputtered NiOx for enhancing efficiency and stability of inverted perovskite solar cells

The quality of the interface between the nickel oxide (NiOx) and the perovskite contact is essential to the efficiency and stability of the device. How to effectively suppress the reaction at the interface between NiOx and perovskite is the key to improve the interface quality. Herein, a simple and scalable interface enhancement strategy for building efficient and stable perovskite solar cells (PSCs) using 4-aminobenzoic acid (ABA) molecules to modify the sputtered NiOx surface as the hole transport layers (HTLs). Meanwhile, ABA molecules not only reduce the defect density and improve the quality of perovskite films (PVK), but also improve the carrier extraction ability of NiOx and reduce interfacial non-radiative recombination. Eventually, the optimized inverted device efficiency is increased to 19.1%, and the device stability is significantly improved under unencapsulated atmospheric conditions. This provides a reference for the commercial development of PSCs.