Numerical simulations of highly efficient Cu2FeSnS4 (CFTS)-based solar cells

Abstract

Cu₂FeSnS₄ (CFTS) is like its counterpart Cu₂ZnSnS₄ (CZTS) a non-toxic and earth abundant material, with a stannite structure. It is a promising material and mainly suitable for the fabrication of low-cost and highly efficient thin film solar cells. In this work, solar cell characteristics using CFTS as the absorber material have been analyzed by numerical simulations. The influence of structural and physical parameters such as the thickness of the absorber layer, acceptor carriers concentrations densities in the absorber layer, as well as effects of back contact metal work function and operating temperature on electrical output parameters of CFTS solar cell have been evaluated by using one dimensional numerical simulation program SCAPS. Simulations results revealed that too large thicknesses affect the fill factor even if they improve slightly the other parameters. We also found that it is not necessary to go beyond a thickness of 3 µm in order to make a tradeoff between the efficiency and the cost. Moreover, it is important to control the carrier density in the absorber for highly efficient CFTS solar cell. By raising the operating temperature, the cell performances are found to be affected. Numerical simulations showed optimized and promising results with the power conversion efficiency (PCE) of 22.33%, fill factor (FF) of 86.26%, short-circuit current density (J_SC) of 25.11 mA/cm² and open circuit voltage (V_OC) of 1.031 V. These results are interesting to define right guidelines and feasible baselines for design and fabrication of low-cost and highly efficient CFTS solar cells.