Fully doctor-bladed planar heterojunction perovskite solar cells under ambient condition

Abstract

Abstract It is highly desirable to develop large-scale, low-cost fabrication techniques to process perovskite solar cells (PSCs) under ambient condition for accelerating their potential commercialization. Herein, efficient planar heterojunction (PHJ) PSCs with a simple structure of ITO/NiOx/CH3NH3PbI3 (MAPbI3)/PC61BM/Ag is fabricated via fully doctor blading under ambient condition with the humidity of ∼40%, in which the NiOx layer, MAPbI3 layer, and PC61BM layer are deposited via doctor blading subsequently. The high-quality perovskite CH3NH3PbI3 films are fabricated by one-step doctor-bladed deposition using modified precursors with the co-solvents of dimethylsulphoxide (DMSO) and dimethylformamide (DMF) along with the suitably excess MAI. The well control on solvent recipe retards the crystallization time, leading to the formation of homogeneous and uniform perovskite film with large-size domains. Furthermore, the excess MAI in the modified precursor ink is helpful to form large-size perovskite grains and high crystallinity. With the optimization, the fully doctor-bladed PHJ-PSCs under ambient condition with the power conversion efficiency (PCE) up to 10.92% is achieved, yielding an average PCE of 10.16%. The research suggests that solvent engineering is a good route for fabricating high-quality perovskite films via one-step, doctor-blading deposition, and it is feasible to achieve efficient PHJ-PSCs through fully doctor-balding technique under ambient condition.