Design and Simulation of FeSi2‐Based Novel Heterojunction Solar Cells for Harnessing Visible and Near‐Infrared Light

Herein, three novel third‐generation (3G) solar cells: n‐Si/p‐FeSi2/p+‐Si, n‐Si/p‐FeSi2/p+‐BaSi2, and n‐CdS/p‐FeSi2/p+‐BaSi2 based on the orthorhombic iron disilicide (β‐FeSi2) absorber are demonstrated theoretically for multikilowatt photovoltaic (PV) systems and space applications. These cells overcome the complication of producing low voltages (≤450 mV) of FeSi2‐based solar cells due to the narrow bandgap (≈0.87 eV) of the absorber. Using crystalline silicon (c‐Si), cadmium sulfide (CdS), and orthorhombic barium disilicide (β‐BaSi2) as junction partners, effects of parameters such as the thickness, doping and defect densities, band offsets, and temperature are studied systematically by a solar cell capacitance simulator (SCAPS‐1D). The highest open‐circuit voltage of 958 mV is attained materially with a 300 nm thin absorber. This article renders the optimization of the PV parameters to improve the device performance with power conversion efficiencies (PCEs) of 28.18%, 31.61%, and 38.93% by the three novel npp+ approaches compared to the PCEs of 15.78% and 24.96% for the solar cells n‐Si/p‐FeSi2 and p‐Si/i‐FeSi2/n‐Si, respectively. Investigation of three novel npp+ heterojunction solar cells based on an FeSi2 absorber is conducted numerically by SCAPS‐1D for potential applications in space and multikilowatt photovoltaic systems. Taking c‐Si, CdS, and BaSi2 as partner materials, the impact of thickness, doping and defect densities, band offsets, and temperature are explored. The highest obtained VOC is 958 mV and PCE is ≈39%.