In this work, methylammonium germanium iodide (CH3NH3GeI3) is considered a highly efficient absorber material for the solar cell structure. Tungsten trioxide (WO3) is chosen as the material for the electron transport layer, while CuSCN is used as the material for the hole transport layer. In the present study, a thin-film device model is developed using germanium (Ge) as an alternative candidate. To control its stability and mitigate its detrimental effects, germanium has been calibrated, demonstrating similar results to Pb-based thin-film solar cells. The simulation results indicate that the CH3NH3GeI3-based solar cell achieves a photovoltaic conversion efficiency of 17.39%, a fill factor of 81.28%, a short-circuit current density (Jsc) of 15.54 mA/cm2, and an open-circuit voltage (Voc) of 1.3764 V. These results show a significant improvement in efficiency, with a maximum efficiency of 17.39% achieved. This study concludes that CH3NH3GeI3-based solar cells exhibit promising performance for solar cell applications. Therefore, for the development of cost-effective and highly efficient thin-film solar cells, this material can be considered a strong candidate.
Srivastava et al. (Sun,) studied this question.