Electron Transport and Thermoelectric Performance of Defected Monolayer MoS2

TL;DR

This study investigates how atomic defects in monolayer MoS2 influence its electronic and thermoelectric properties, revealing defect-induced tunability of the band gap, magnetism, and enhanced thermoelectric performance.

Contribution

It provides a detailed theoretical analysis of defect effects on MoS2's electronic structure and thermoelectric efficiency, highlighting potential applications in electronics and thermal management.

Findings

Defects exhibit endothermic formation energies.

Atomic defects tune the band gap of MoS2.

Defected MoS2 shows reduced thermal conductivity and higher thermoelectric figure of merit.

Abstract

Electronic and thermoelectric properties of a two-dimensional MoS2 monolayer containing atomic defects are investigated using density functional theory. All the atomic defects have been found to exhibit endothermic nature. Electronic structure of MoS2 shows tuneability of band gap with the atomic defects. The MoS2 vacancy in pristine monolayer makes it magnetic and narrow band gap semiconductor. The spin-polarized character of the monolayer with defects is clearly captured by the tunneling current calculated in the STM-like setup. A relatively low thermal conductivity has been observed in monolayers with defects as compared to pristine form resulting in enhanced room temperature figure of merit as high as 6.24 and 1.30 respectively. We believe that our results open up a new window for the use of monolayer MoS2 in electronic devices, thermal management and thermoelectric devices.