Electronic structure and thermoelectric properties of orthorhombic spinel-derived AgInSnS4 compound: First-principles investigation

Abstract

The electronic structure and thermoelectric properties of the orthorhombic spinel-derived AgInSnS4 compound were investigated using the Linearized Full-Potential Augmented Plane Wave Method (FP-LAPW), which is fundamentally based on density functional theory (DFT), in combination with semi-classical Boltzmann transport theory. According to the electronic band structure calculation, the AgInSnS4 compound is a semiconductor with a fundamentally reduced indirect bandgap of about 0.50 eV and 1.27 eV obtained within the GGA-PBE and TB-mBJ approaches, respectively. Moreover, the evaluation of the thermoelectric properties shows that the AgInSnS4 compound has a large Seebeck coefficient combined with high electrical conductivity, resulting in a high figure of merit (ZT) value of 0.81 at high temperature, making it a suitable candidate for thermoelectric applications.