Opto-electronic and thermoelectric properties of MgIn2X4 (X = S, Se) spinels via ab-initio calculations.

Abstract The structural behavior of MgIn 2 X 4 (X = S, Se) has been elaborated by FP-LAPW + lo method as included in the Wien2k code. The stability of the phase has been confirmed by negative formation energy (−1.24 eV for MgIn 2 S 4 and -0.78 eV for MgIn 2 Se 4). The band gap dependent opto-electronic and thermoelectric properties are realized by modified Becke-Johnson exchange potential. The electronic band gap tuned from ultraviolet to visible (3.1 eV and 1.9 eV) by replacing the S with Se that motivated the studied spinels for photovoltaic and solar applications. Moreover, the attenuation of light, dispersion, transparency, reflection and energy loss when light scattered from material are discussed as function of energy. The thermal conductivity to electrical conductivity ratio, potential gradient and thermal efficiency in the range 0.78–0.80 are elaborated. The comparative study of opto-electronic and thermoelectric properties for energy harvesting increases the potential for optoelectronic than thermoelectric applications. Graphical abstract The Figure of merit (ZT) values of MgIn 2 X 4 (X = S, Se) spinels against (a) chemical potential and (b) temperature. Image 1 Highlights • The study of structural behavior of MgIn 2 X 4 (X = S, Se) by using DFT. • The investigation of band gap dependent opto-electronic and thermoelectric properties. • The band gap tuning from ultraviolet to visible by changing anion. • The high value of thermal efficiency increases importance for thermoelectric applications. [ABSTRACT FROM AUTHOR]