Study of electronic, mechanical, thermodynamic, optical, and thermoelectric properties of CdLa2X4 (X = S, Se, Te) chalcogenides for solar cells and energy applications

Abstract

Spinels chalcogenides are an emerging aspirant for renewable energy which attained huge potential from the last decade. Therefore, the electronic structure, and mechanical properties are discussed by DFT approach. The Born stability criteria, and formation energies (−2.0, −1.98, −1.93) eV have been computed to assure mechanical, and thermodynamic stabilities. The ductile nature (υ > 0.26, and B/G > 1.75), hardness, Debye temperature, and lattice thermal conductivities are addressed in terms of elastic constants, and elastic modulus. The band gaps (2.0, 1.7, 0.85) eV for CdLa2X4 (X = S, Se, Te) have been calculated from band structures. The polarization of light, absorption bands in visible regions, refractive index, and reflection of light energy have made them significantly important materials for solar cells. Furthermore, transport characteristics are revealed by Seebeck coefficient, electrical & thermal conductivities, and figure of merit (ZT). The ZT has values 1.0, 0.80, and 0.66 at room temperature for CdLa2X4 (X = S, Se, Te) which increases their significance for thermoelectric devices.