Doped tin induced structural evaluation and performance of CH3NH3PbxSn1-xI3 thin films prepared by a simple route of unisource thermal evaporation

The photoelectric conversion efficiency of organic-inorganic halide perovskite solar cell has made a great progress in recent years. In this paper, we attempted to gradually replace lead with tin and synthesize perovskite thin films of different lead-tin proportion with a unisource thermal evaporation method. The morphology, crystallinity and transmittance of the perovskite thin films were studied for revealing the effect of different lead and tin proportion on the properties of the perovskite thin films. The results show that the morphology was ameliorated and the crystallinity of CH3NH3Pb0.4Sn0.6I3 thin film was improved. The absorption edge of CH3NH3Pb0.7Sn0.3I3 was moved to the long wavelength. The surface of the perovskite thin films was smoother and the quality of the thin films has been greatly improved.