Measurement of the thermal conductivities of suspended MoS₂ and MoSe₂ by nanosecond ET-Raman without temperature calibration and laser absorption evaluation

Abstract

Nanosecond ET-Raman measures the thermal conductivity of 2D materials without temperature calibration and laser absorption evaluation and features the highest accuracy.

Nanostructured and Heterostructured 2D Materials for Thermoelectrics

“…[55] These accurate measurements of the bulk crystals provide a baseline for understanding thermal transport in 2D TMDCs. The thermal conductivities of single-and few-layer TMDCs have been reported by a few Raman-based [57][58][59][60][61][62][63] and micro-bridge-based [64][65][66] measurements, but the limited data scattered in a large range (between ～15 and ～100 W/m•K at RT for monolayer MoS2). Meanwhile, careful MD simulations, [68], [50] first-principles [67] and BTE [69] calculations agreed well on the in-plane thermal conductivities of 2D MoS2.…”

Thermal Conductivity Measurements in Atomically Thin Materials and Devices

“…Thus, with the known mean temperature under the laser spot, the heat equation for the suspended and the supported part can be solved to give the thermal conductivity. The method is employed on various thin layers such as MoSe 2 [26,27], WS 2 [28] (Fig. 2.2)…”

Thermal conductance between water and nm-thick WS2: extremely localized probing using nanosecond energy transport state-resolved Raman

“…More details of this process could be found in our previous works. 45,46 The Si substrate with the WS2 film on top of it is mounted on a stage inside a glass container. This container is filled with DI water.…”

“…The thickness affects the heat conduction in the sample and the laser absorption (multiple reflections in 2D samples and optical interference effect). Note that for TMD materials, k increases gradually with increased thickness for more than ~5 nm samples and it reaches the bulk k value at larger thicknesses 45,59,60. A 3D numerical calculation based on the finite volume method is conducted to find int R and consequently interfacial thermal conductance (Gint).…”