Perovskite Thin Film Consisting with One-Dimensional Nanowires

Organic-inorganic hybrid perovskite solar cells had attracted extensive attention due to their high-power conversion efficiency and low cost. The morphology and structure of the light absorption layer are crucially important for the device performance. The one-dimensional or two dimensional nano-structure perovskite material exhibits better optical and electrical properties than three-dimensional bulk perovskite. In this article, the perovskite CH3NH3PbI3 thin films with one-dimensional nanowires structure were prepared while using the solution method with N,N-Dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) mixed solvent under atmospheric environment. During the perovskite thin films growth, the DMSO solvent as a structure directing agent played a guiding role in the formation of nanowires. The effects of DMSO solvent added ratio on the perovskite thin film structure, morphology, optical properties, and the device performance were studied. By changing the ratio of DMSO solvent added can effectively adjust the orientation order and optical properties of the nanowires perovskite thin films. The results showed that the best ratio of DMSO solvent added in the mixed solvent was 10%. The high order orientation of the perovskite thin film with nanowires forest was obtained. It showed the high optical absorption and electrical properties. The perovskite absorption layer presents ordered and dispersed nanowires forest; the device power conversation efficiency is increased by 50% when compared with the perovskite layer presents disordered nanowires.