Influence of ZnSe Donor Doping and Resistive Parameters on the Photovoltaic Performance of an MASnI₃ Perovskite Solar Cell: A SCAPS-1D Numerical Study

Abstract

Perovskite solar cells are promising next-generation photovoltaic devices, but their performance is strongly influenced by charge-transport losses and parasitic resistive effects. This study numerically investigates the influence of ZnSe donor concentration, series resistance (Rs), and shunt resistance (Rsh) on an FTO/ZnSe/MASnI₃/Graphene/Au perovskite solar cell using SCAPS-1D. Simulations were performed under AM1.5G illumination of 1000 W m⁻² at 300 K. The ZnSe donor concentration was varied from 10¹⁵ to 10²² cm⁻³, while Rs was varied from 0.2 to 1.6 Ω cm² and Rsh from 2000 to 3400 Ω cm². The optimum baseline performance occurred at a ZnSe donor concentration of 10¹⁷ cm⁻³, yielding Voc = 1.139 V, Jsc = 27.215 mA cm⁻², FF = 88.675%, and PCE = 27.486%. At 10¹⁹ cm⁻³, PCE decreased sharply to 21.586%, indicating the adverse effect of excessive doping. Increasing Rs from 0.2 to 1.6 Ω cm² reduced FF from 88.222% to 85.060% and PCE from 27.346% to 26.367%, while Voc and Jsc changed only marginally. Increasing Rsh from 2000 to 3400 Ω cm² increased FF from 86.991% to 87.684% and PCE from 26.948% to 27.170%. The integrated optimized configuration reported in the MSc study achieved Jsc = 30.89 mA cm⁻², Voc = 1.23 V, FF = 78.29%, and PCE = 29.70%. The results show that controlled ZnSe doping, low series resistance and sufficiently high shunt resistance are important for minimizing electrical losses and improving charge extraction.