Investigation for Thermoelectric Properties of the MoS2 Monolayer-Graphene Heterostructure: Density Functional Theory Calculations and Electrical Transport Measurements

Sujee Kim; Changhoon Lee; Young Soo Lim; Ji-Hoon Shim

doi:10.1021/acsomega.0c04488

Investigation for Thermoelectric Properties of the MoS₂ Monolayer-Graphene Heterostructure: Density Functional Theory Calculations and Electrical Transport Measurements

ACS Omega. 2020 Dec 31;6(1):278-283. doi: 10.1021/acsomega.0c04488. eCollection 2021 Jan 12.

Authors

Sujee Kim¹, Changhoon Lee^{2

3}, Young Soo Lim⁴, Ji-Hoon Shim^{1

2

5}

Affiliations

¹ Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, Pohang 37673, Korea.
² Department of Chemistry, Pohang University of Science and Technology, Pohang 37673, Korea.
³ Max Planck POSTECH Center for Complex Phase of Materials, Pohang University of Science and Technology, Pohang 37673, Korea.
⁴ Department of Materials System Engineering, Pukyong National University, Busan 48547, Korea.
⁵ Division of Advanced Materials Science, Pohang University of Science and Technology, Pohang 37673, Korea.

Abstract

We investigated the thermoelectric (TE) properties of the MoS₂ monolayer-graphene heterostructure which consists of the MoS₂ monolayer and graphene. The electronic structures of the MoS₂ monolayer-graphene heterostructure are mainly contributed from graphene and the MoS₂ monolayer for the valence band maximum and conduction band minimum, respectively. The change in the electronic structures near the Fermi level is responsible for the fact that the calculated Seebeck coefficients S and electrical conductivity σ/τ of MoS₂ monolayer-graphene are largely affected from those of graphene and the MoS₂ monolayer. Its power factor S ²σ/τ is increased compared to those of graphene and the MoS₂ monolayer at an electron concentration of 10¹¹ to 10¹² cm^-2, which corresponds to a three-dimensional concentration of 3 × 10¹⁸ to 3 × 10¹⁹ cm^-3. We also demonstrated that the MoS₂ monolayer shows the p-type TE behavior, while the MoS₂ monolayer-graphene heterostructure is given to the n-type TE material. The current study provides a strategy to improve TE properties of the MoS₂ monolayer through the formation of the MoS₂ monolayer-graphene heterostructure.