Disodium Benzodipyrrole Sulfonate as Neutral Hole-Transporting Materials for Perovskite Solar Cells
journal contributionposted on 06.04.2018, 17:05 by Rui Shang, Zhongmin Zhou, Hiroki Nishioka, Henry Halim, Shunsuke Furukawa, Izuru Takei, Naoya Ninomiya, Eiichi Nakamura
Hole-transporting material (HTM) is an indispensable constituent in organic electronic devices, generally comprising a donor/dopant combination. We report that a disodium salt of substituted benzo[1,2-b:4,5-b′]dipyrrole bearing two racemic alkanediylsulfonate anion side chains (BDPSOs) serves as a neutral, nonhygroscopic, dopant-free HTM for lead perovskite (MAPbI3) solar cells. These organic/inorganic hybrid molecules are useful for tunable orbital level and controllable solubility. A fluorinated BDPSO has an energy level matched with MAPbI3, affording an inverted-structure solar cell that performs with 17.2% efficiency with minimal hysteresis. The solar cell devices fabricated using BDPSOs showed remarkable storage and operational stability.