Anisotropic thermoelectric figure of merit in [formula omitted] monolayer

Abstract

Herein we have studied the anisotropic thermoelectric properties of MoTe2 monolayer using density functional and semiclassical Boltzmann transport theory. The electrical and thermal properties are evaluated by considering electron–phonon and phonon–phonon scattering mechanisms. Enhancement of figure of merit (ZT) is observed along the armchair direction for both n-type and p-type MoTe2 monolayer. Strong anisotropic ZT is found for p-type carriers due to anisotropic nature of electrical conductivity. The calculated thermoelectric figure of merit (ZT) is 1.33 for n-type and 0.83 for p-type monolayer at 700 K along the armchair orientation. ZT of MoTe2 monolayer is ∼ 30 times larger than the ZT value for bulk MoTe2 (0.034 at 700 K). This high anisotropic ZT will be useful to design 2D material based transverse TE devices.