A dual functional additive for the HTM layer in perovskite solar cells

Abstract

The ionic liquid N-butyl-N'-(4-pyridylheptyl)imidazolium bis(trifluoromethane)sulfonimide (BuPyIm-TFSI) was used as a dual-functional additive to improve the electrical properties of the hole-transporting material (HTM) for perovskite solar cells. BuPyIm-TFSI improved the conductivity of HTM and reduced the dark current of the solar cell simultaneously, thereby greatly increasing the power conversion efficiency.