Electrostatic modulation of thermoelectric transport properties of 2H-MoTe2

Published

September 6, 2023

Author(s)

Tianhui Zhu, Sree Sourav Das, Safoura Nayebsadeghi, Fajana Tonni, Sergiy Krylyuk, Costel Constantin, Keivan Esfarjani, Albert Davydov, Mona Zebarjadi

Abstract

Two-dimensional layered transition metal dichalcogenides are potential thermoelectric candidates with application in on-chip integrated nanoscale cooling and power generation. Here, we report a comprehensive experimental and theoretical study on the in-plane thermoelectric transport properties of thin 2H-MoTe2 flakes prepared in field-effect transistor geometry to enable electrostatic gating and modulation of the electronic properties. The thermoelectric power factor is enhanced by up to 45% using electrostatic modulation. The in-plane thermal conductivity of 9.8 ± 3.7 W m−1 K−1 is measured using the heat diffusion imaging method in a 25 nm thick flake. First-principles calculations are used to obtain the electronic band structure, phonon band dispersion, and electron–phonon scattering rates. The experimental electronic properties are in agreement with theoretical results obtained within energy-dependent relaxation time approximation. The thermal conductivity is evaluated using both the relaxation time approximation and the full iterative solution to the phonon Boltzmann transport equation. This study establishes a framework to quantitively compare first-principle-based calculations with experiments in 2D layered materials.

Citation

Energy Advances

Volume

2

Pub Type

Journals

Download Paper

https://doi.org/10.1039/d3ya00316g

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Keywords

MoTe2, Seebeck coefficient, thermal conductivity

Citation

Zhu, T. , Das, S. , Nayebsadeghi, S. , Tonni, F. , Krylyuk, S. , Constantin, C. , Esfarjani, K. , Davydov, A. and Zebarjadi, M. (2023), Electrostatic modulation of thermoelectric transport properties of 2H-MoTe2, Energy Advances, [online], https://doi.org/10.1039/d3ya00316g, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=956210 (Accessed April 29, 2024)