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

Abstract

Herein, three novel third‐generation (3G) solar cells: n‐Si/p‐FeSi 2 /p + ‐Si, n‐Si/p‐FeSi 2 /p + ‐BaSi 2 , and n‐CdS/p‐FeSi 2 /p + ‐BaSi 2 based on the orthorhombic iron disilicide (β‐FeSi 2 ) absorber are demonstrated theoretically for multikilowatt photovoltaic (PV) systems and space applications. These cells overcome the complication of producing low voltages (≤450 mV) of FeSi 2 ‐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‐BaSi 2 ) 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‐FeSi 2 and p‐Si/i‐FeSi 2 /n‐Si, respectively.