2-T Non-Toxic Multijunction solar cell with Diverse ETL materials

Halide perovskites are attractive prospects for extremely effective solar absorbers because of their superior optical qualities, increased efficiency, lightweight, and low price. This paper explores a tandem solar cell device structure utilizing the solar cell capacitance simulator (SCAPS), employing wide-bandgap perovskite, i.e., NaZn0.7Cu0.3Br3, as the top cell and narrow bandgap perovskite, i.e. MASnI3 as the bottom cell. Here, current matching over two sub-cells is performed by adjusting the thickness of both the active layers and an optimal efficiency of 30.92 % was found at active layer thicknesses of 20 nm and 700 nm for the upper and lower sub-cells, correspondingly. In this research, the effects of absorber layer thickness and diverse electron transport layers on the suggested solar cells' performance characteristics are studied. The suggested perovskite/perovskite tandem solar cell exhibits excellent photovoltaic properties, including an open circuit voltage (Voc) of 1.0054 volts, a short circuit current density (Jsc) of 35.03 mA/cm², a fill factor (FF) of 87.79%, and an efficiency(ƞ) of 30.92%.