Resistance dynamics in a solar cell with novel lead-free perovskite absorbers (LiMgI3 and NaMgI3): Performance optimization using SCAPS-1D simulation and impedance spectroscopy

The lead-free perovskite is regarded as a significant advancement in the realm of safe, clean energy due to its prolonged stability. This development has led to a vast array of opportunities to fabricate optimal absorber layers that can achieve these objectives. The present study utilizes a novel lead-free perovskite as an absorber layer, employing compounds of LiMgI₃ and NaMgI₃ as promising materials for photovoltaic applications. This study enables an examination of the impact of the electronic affinity, thickness, and defect density of the absorber layers. It also enables an examination of the impact of interfacial defects. Furthermore, the utilization of alternative HTLs enables the identification of the most suitable one for our devices. Following this identification process, the back contact work function is investigated. Each effect studied is accompanied by an impedance spectroscopy analysis. By applying the optimized parameters identified in this study, the best performance was achieved. For LiMgI₃, the results include a Voc of 1.233 V, a Jsc of 33.43 mA/cm², a FF of 85.67 %, and a PCE of 35.31 %. Similarly, for NaMgI₃, the values obtained were 1.248 V for Voc, 33.25 mA/cm² for Jsc, 85.88 % for FF, and 35.62 % for PCE.