Suppressed hysteresis and improved stability in perovskite solar cells with conductive organic network

Advancing lead halide perovskite solar cells to photovoltaic application requires reproducible and stable devices using low-cost fabricating techniques. Here a device structure is developed with organic network uniformly incorporated into the organic/inorganic hybrid perovskite film by one-step solution-processing strategy, which significantly improves the photovoltaic performance and long-term stability of planar type perovskite solar cells. The organic network is composed with PCBM and PEG. Therein, a long-chain insulating polymer PEG acts as a network to improve film morphology, as well as device stability. The fullerene derivative PCBM in the composite forms conducting channels to assist the charge transfer and transport in perovskite film. Besides, PCBM in perovskite film can passivate trap states on grain boundaries, so that the photocurrent hysteresis of the device is suppressed significantly. This organic composite network enhances the photovoltaic performance of perovskite solar cells with maximum power conversion efficiency of 17.1%, showing long duration at the maximum power point tracking up to ~170 min. This low-cost organic network demonstrates a promising method for industry-scale fabrication of the organic/inorganic hybrid perovskite solar technology.