Intensifying bismuth concentration in tin chalcogenide for solar cell applications

Abstract

Solar cells convert electricity from the solar spectrum to more than 60%. Researchers focused on this promising field because of the most demanding renewable source of electrical energy. Based on the demand, we focused our study on bismuth-doped tin chalcogenide materials for the optoelectronic and solar cell applications. The effect of bismuth concentration on structural, electronic, thermodynamic and optical properties of Sn[Formula: see text]Bi[Formula: see text]Te and Sn[Formula: see text]Bi[Formula: see text]Te materials is studied based on density functional theory (DFT). Generalized gradient approximation (GGA) was proposed to calculate structural parameters, density of states and band structure. Here the lattice parameter increases when increasing bismuth concentration. The parent binary SnTe is in semiconducting behavior with a narrow direct bandgap of 0.234 eV (L-L). From the calculated thermal and optical results, the Gruneisen parameter is maximum for Sn[Formula: see text]Bi[Formula: see text]Te and Debye temperature is maximum for Sn[Formula: see text]Bi[Formula: see text]Te. The studied materials are consistent in IR, visible and UV regions and they are adorable for IR optical detectors and solar cell applications.