Investigation of CsPbBr3 films with controllable morphology and its influence on the photovoltaic properties for carbon-based planar perovskite solar cells

Abstract

Recently, inorganic C s P b B r 3 perovskites have received much research interest in the photovoltaic field owing to their excellent stability. However, it is still challenging to prepare high-performance C s P b B r 3 films with good crystallinity and superior morphology at moderate temperatures. In this work, we report a novel, to the best of our knowledge, multistep spin-coating deposition method to prepare C s P b B r 3 perovskite film. Through optimizing the number of deposition cycles of a CsBr solution, C s P b B r 3 films containing high phase purity, good crystallinity, and strong absorption are obtained. The inorganic planar perovskite solar cell with optimized C s P b B r 3 film realizes a maximum power conversion efficiency of 4.70% under standard solar illumination conditions. Moreover, our devices with F T O / T i O 2 / C s P b B r 3 / C u P c / C exhibit fabulous stability when stored in an ambient atmosphere with ∼ 40 % humidity for 60 days. Our work provides new opportunities for facilitating practical application of C s P b B r 3 planar perovskite solar cells.