A comprehensive device modeling of organic-inorganic hybrid CH3NH3GeI3 based perovskite solar cell

Organic-inorganic lead-based perovskite solar cells (PSCs) have emerged as a promising and rapidly evolving photovoltaic technology in recent years. However, the use of high-toxic lead material in PSC is incompatible with the 12^th sustainable development goal and restricts the potential for commercialization. Recently, lead-free methylammonium germanium tri-iodide (CH₃NH₃GeI₃)-based hybrid perovskite solar cells have garnered substantial attention in the field of photovoltaics due to their remarkable combination of high efficiency. The exceptional photovoltaic performance of hybrid CH₃NH₃GeI₃ perovskite solar cells is the central theme of this study. Where emphasis has been given to attaining high power conversion efficiency by adjusting various parameters of the CH₃NH₃GeI₃ perovskite layer using a solar cell capacitance simulator (SCAPS-1D). Moreover, the influence on parameter changes, i.e., thickness, doping concentration, quantum efficiency, and defect density of perovskite, ETL, HTL, HTL/CH₃NH₃GeI₃, and CH₃NH₃GeI₃/ETL layers, has been explored. The unique FTO/ZnO/CH₃NH₃GeI₃/Cu₂O/Ni-structured perovskite solar cell demonstrates impressive simulative performance with a V_OC of 1.39 V, J_SC of 21.93 mA/cm², a fill factor of 79.82 %, and an efficiency of 24.46 %. CH₃NH₃GeI₃ is a promising candidate that can be employed as a perovskite layer, and if fabricated properly, FTO/ZnO/CH₃NH₃GeI₃/Cu₂O/Ni perovskite solar cell has the possibility to be a competitive alternative to conventional silicon-based photovoltaics.