A theoretical comparison between CH3NH3PbI3 and CH3NH3SnI3 based solar cells

Abstract

The perovskite materials based photovoltaic cells play a crucial role in the conversion of sunlight into electric energy. The commonly used perovskite materials are CH3NH3PbI3 and CH3NH3SnI3. In the present manuscript, a theoretical comparison is done by simulating the structures ITO/TiO2/CH3NH3PbI3/p-Gr/Ag and ITO/TiO2/CH3NH3SnI3/p-Gr/Ag structures in AFORS-HET software under the illumination condition of AM 1.5G. Here, TiO2 and p-Graphene (p-Gr) play the role of electron transporting material and hole transporting material respectively with ITO and Ag as front and back contacts. The thickness of layers is directly related to the cost of the cells. Therefore we optimized the CH3NH3PbI3 and CH3NH3SnI3 layers thickness to observe the performance of the device. The power conversion efficiency of 10.62% is obtained for CH3NH3SnI3based solar cell at optimized thickness of 800 nm as compared to 9.74% efficiency for CH3NH3PbI3based solar cell at an optimized thickness of 700 nm. The textured nature of front surface also enhances the efficiency 10.56% and 12.38% for CH3NH3PbI3 and CH3NH3SnI3 respectively.