Efficient and stable inverted perovskite solar cells incorporating 4-Fluorobenzylammonium iodide

Abstract

Abstract Improving the stability of high-performance perovskite solar cells (PVSCs) against humid air poses a substantial challenge for their future development. To address this issue, here we have incorporated a trace amount of 4-fluorobenzylammonium iodide into MAPbI3 based PVSCs, and significantly improved the efficiency and stability. Through spectroscopy measurements, space charge limited current analysis, etc., we find that the incorporation of 4-fluorobenzylammonium iodide can passivate defects, improve charge transport, and thus, increase the power conversion efficiency (PCE) from 18.1% to 19.1%. In the meanwhile, the fluorinated benzene moiety confers the hydrophobic character to the perovskite film and device, and enhances the device stability against moisture. This work should have implication toward stable and high-performance PVSCs for commercialization.