  Recent developments in the 2D materials laid emphasis on finding the
materials with robust properties for variety of applications including the
energy harvesting. The recent discovery of Janus monolayers with broken
symmetry has opened up new options for engineering the properties of 2D layered
materials. Present study focuses on enhancing thermoelectric properties of
2H-ISbTe 2D Janus monolayer. All the calculations have been performed using
fully relaxed unit cell and employing the pseudo potential based quantum
espresso code. Calculated structural parameters are in good agreement with
previous literature reports. The lattice dynamics calculations predicts this
monolayer can withstand a strain of up to 4% beyond which imaginary frequencies
appear in the phonon dispersion curves. Computed electronic structure reveals
that the monolayer is an indirect wide bandgap material and the bandgap
decreases with tensile strain. Furthermore, the computed thermoelectric
properties show that the studied monolayer has high Seebeck coefficient of ~
300 {\mu}V/K and low thermal conductivity which yields reasonably high ZT of ~
1.31 for a strain of 2% at 300 K with p-type doping. Therefore, our study
signifies the fact that tensile strain and p-type doping of 2D Janus monolayer
ISbTe can enhance ZT from 0.87 to 1.31 at room temperature which makes it a
promising candidate for thermoelectric applications.
