895
Views
12
Crossref
10
WoS
13
Scopus
0
CSCD
Understanding the substrate and temperature effect on thermal transport properties of transition metal dichalcogenides (TMDs) monolayers are crucial for their future applications. Herein, a dual-wavelength flash Raman (DF-Raman) method is used to measure the thermal conductivity of monolayer WS2 at a temperature range of 200–400 K. High measurement accuracy can be guaranteed in this method since the influence of both the laser absorption coefficient and temperature-Raman coefficient can be eliminated through normalization. The room-temperature thermal conductivity of suspended and supported WS2 are 28.5 ± 2.1 (30.3 ± 2.0) and 15.4 ± 1.9 (16.9 ± 2.1) W/(m·K), respectively, with a ~ 50% reduction due to substrate effect. Molecular dynamics (MD) simulations reveal that the suppression of acoustic phonons is mainly responsible for the striking reduction. The behaviors of optical phonons are also unambiguously investigated using Raman spectroscopy, and the in-plane optical mode, E
This work was supported by the National Natural Science Foundation of China (Nos. 51827807, 51972191, and 52130602).