High quality perovskite film solar cell using methanol as additive with 19.5% power conversion efficiency

In this paper, a novel one-step solution approach is developed to prepare high quality methylammonium lead trihalide (MAPbI3) perovskite films. This approach employs methanol as additive, which is added into the perovskite precursor solution. The use of methanol can enhance the absorption of MAPbI3 and significantly improve the coverage of MAPbI3 on a planar substrate. The fabricated perovskite solar cell (PSC) with methanol exhibits a higher power conversion efficiency (PCE) compared with that without methanol (19.51% vs 16.53%). Furthermore, the power conversion efficiencies of devices with methanol are still high after kept in dark under ambient environment for 30 days. This work provides a method to prepare high quality perovskite films for planar perovskite solar cells with high performance. A novel one-step solution is reported to prepare perovskite films by adding methanol into the perovskite precursor solution. The use of methanol can enhance the absorption of CH3NH3PbI3 and significantly improve the coverage of CH3NH3PbI3 on a planar substrate. The fabricated perovskite solar cell with methanol exhibits a higher power conversion efficiency compared with that without methanol (19.51% vs 16.53%). [Display omitted] •Methanol was employed as additive successfully for perovskite solar cells.•The methanol-treated PSCs showed remarkable efficiency and enhanced stability.•The methanol-treated method can suppress the hysteresis.