Performance analysis of lead-free halide double perovskite-based photovoltaic devices for solar cell conception

Abstract

The conception and modeling of a photovoltaic cell are done by combining the density functional theory (DFT) and solar cell capacitance simulator (SCAPS). The search for new lead-free halide semiconductor perovskite materials with an appropriate band gap, which can be used as good absorbers of solar radiation in the studied photovoltaic cell, is realized by substituting a percentage of sodium (Na) with potassium (K) and sulphur (S) in the double perovskite Cs2NaCrCl6. The study also focuses on the choice of the best materials for the electron transport layer (ETL) and the hole transport one (HTL) as well as the thickness of the perovskite semiconductor materials Cs2Na1−xXxCrCl6 (X = S and K). The results reveal that Cu2O and WS2 are suitable materials for HTL and ETL layers, respectively. The optimal thickness of the perovskite semiconductor is equal to 2μm. Under optimized conditions, the photovoltaic device power conversion efficiency (η) equals 15.01 % and 20.01 % by using Cs2Na0.5K0.5CrCl6 with Eg = 1.8eV and Cs2NaCrCl6 with Eg = 1.6eV as active layer, respectively. Therefore, the obtained photovoltaic cell model is (Cu2O/Cs2NaCrCl6/WS2/FTO), with an efficiency of η = 20.01 %.