Optimization of Electron Transport Layer-Free Cs2TiBr6/MASnBr3 Laminated Structure Perovskite Solar Cells by SCAPS-1D Simulation

Abstract

Cs2TiBr6 materials have promising applications in organic–inorganic halide perovskite solar cells (PSCs), but their power conversion efficiency (PCE) is low. Herein, based on the matching band structure of MASnBr3 and Cs2TiBr6, a no-electron transport layer (ETL)-structured laminated PSC is constructed for numerical simulation using SCAPS-1D. The results have shown that the ETL-free structure reduces the potential barrier between the interfaces and improves the performance of the device. MASnBr3 is used to replace the traditional hole transport layer to form a laminated structure, which is more conducive to the built-in electric field of the device. Through exploring the internal influencing factors and applicable environment, it is found that the device can maintain a good operating level between 230 and 430 K. Finally, the best PCE of 19.63% is achieved in the proposed device structure (FTO/Cs2TiBr6/MASnBr3/Au). This work provides a new approach to achieving lead-free and efficient laminated PSCs in a wide temperature range of usage environments from −43 to 157 °C.