Elucidating the Impact of Thin Film Texture on Charge Transport and Collection in Perovskite Solar Cells.

Organic-inorganic halide perovskites have emerged as one of the most promising materials for photovoltaic applications. Because of the polycrystalline nature of perovskite thin films, it is crucial to investigate the impact of microstructures on device performance. In this study, we employ ramp-annealing to tailor the texture of perovskite thin films via controlling the nucleation of perovskite grains. Electrochemical impedance spectroscopy studies further suggest that the thin film texture impacts not only the charge collection at the contact but also the carrier transport in the bulk perovskite layer. The combination of the two effects leads to enhanced performance in devices constructed of preferentially oriented perovskite thin films.