Ag doped ZnSe as electron transport layer with enhanced electron mobility and better band alignment for efficient lead free - all inorganic CuBiSC_l2 perovskite solar cells: a simulation

Abstract Lead (Pb) based perovskite solar cells (PSCs) have an impressively high-power conversion efficiency (PCE). However, the commercialization of these PSCs is significantly hindered by Pb toxicity. The present work examines the impact of Ag doping in ZnSe electron transport layer (ETL) for the better performance of all inorganic CuBiSCl 2 PSCs by using SCAPS-1D simulation package. The photovoltaic parameters were optimized by adjusting the perovskite layer thicknesses and charge transport layers (CTLs), along with doping concentration, interfacial defect density. Additionally, optimizing series and shunt resistance significantly enhances PSC performance, with optimal value of 1 Ω·cm 2 and 6000 Ω·cm 2 , respectively, leading to improved PCE and reduces resistive losses. The most efficient PSC with PCE of 29.36%, V OC = 1.10 V, J SC = 32.57 mA cm −2 , and FF = 81.76 % was attained with the structure of FTO/Ag-ZnSe/CuBiSCl 2 /Cu 2 O. The effect of doping of Ag in ZnSe ETL was proven to be better choice for efficient CuBiSCl 2 PSC. Further, this study examined the performance of optimized PSC in terms of capacitance-voltage, mott—Schottky, and Nyquist plot. The achieved PCE of 29.36% is significantly higher than the previously reported 1.00% for CuBiSCl 2 -based solar cells using TiO 2 as the ETL. This investigation highlights the effectiveness of Ag-doped ZnSe as an ETL by offering the better electron mobility and band alignment and in the solar cell. These findings establish CuBiSCl 2 as a promising active layer for high-performance, eco-friendly, and all inorganic PSCs.