The efficient and non-hysteresis inverted non-fullerenes/CH3NH3PbI3 planar solar cells

Three kinds of IT-like non-fullerene electron acceptors, acting as electron transport layer, were introduced into the inverted perovskite solar cell. Based on systemically adjusting the thickness of the electron transport layer, the devices with three indacenodithieno[3,2-b]thiophene (IT) like (IT-like) non-fullerene acceptors wholly performed better superiority than that based on phenyl-C61-butyric acid methyl ester (PCBM), and a high efficiency of 14.29% was achieved by the device with ITIC electron transport layer. Comparing the detail parameters, the open-circuit voltage is all enhanced because the recombination loss is further suppressed with PCBM replacing by IT-like non-fullerenes. More importantly, the IT-like non-fullerenes show an unparalleled ability in extraction and transportation of photo-generated carrier and the radiation loss is largely inhabited. Benefits from the high quality perovskite film, lower recombination loss and trap passivation, the abnormal hysteresis effect is dramatically suppressed by IT-like non-fullerenes. By comparing with PCBM based devices, the hysteresis index (HI) of the inverted PSCs based on ITIC, ITIC-Th and IT-M are 1.78, 1.35, 1.83 and reduced by 47%, 46% and 60%, respectively. This work preliminary reveal the obvious advantage for the application of IT-like non-fullerenes in inverted perovskite solar cells, which shows great potential in preparing non-hysteresis, high efficient inverted perovskite solar cells.