Model-based optimization of KGeCl₃ perovskite solar cells for lead‑free inorganic photovoltaic conversion
DOI:
https://doi.org/10.22399/ijcesen.5527Keywords:
Perovskite, Photovoltaic, Modelling, High-EfficiencyAbstract
The performance and optimization of a perovskite solar cell employing an inorganic, lead‑free absorber with a 1.1 eV bandgap were investigated using numerical modeling and simulation. The FTO/TiO2/KGeCl3/Spiro‑OMeTAD/Au, architecture was assessed while layer thicknesses, doping concentrations, and bulk defect densities of the ETL, absorber, and HTL were varied, and while interfacial defect densities at the ETL/absorber and absorber/HTL junctions were modified. Additionally, 36 device configurations combining different ETL and HTL materials were compared. These simulations provided useful information for structural optimization and performance improvement; a maximum conversion efficiency of 21.11% was achieved with the optimized single-junction structure FTO/SnS2/KGeCl3/MoS2/Au, and 28.36 % with the FAPbI3/KGeCl3 tandem structure. The potential of KGeCl₃ as a lead-free perovskite absorber was thus demonstrated, and the prospects for the future development of sustainable photovoltaic devices were highlighted.
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