Measurement of Thermal Conductivity of Suspended and Supported Single-Layer WS₂ Using Micro-photoluminescence Spectroscopy

Abstract

In this work, the micro-photoluminescence (PL) technique is applied to study the thermal transport properties of single-layer transition-metal dichalcogenide materials WS2 grown by chemical vapor deposition. By comparing the temperature-dependent Raman spectrum with the PL spectrum, we prove that the PL implementation can provide both higher temperature sensitivity (4–5 times) and stronger signal response (∼100 times), which may largely reduce the uncertainties and time consumption for thermal conductivity measurements. By use of temperature- and power-dependent PL measurements, the in-plane thermal conductivity of the suspended single-layer WS2 is derived as ∼63 ± 7 W/m·K. Moreover, by examining the power-dependent PL response of the SiO2/Si substrate-supported single-layer WS2 using different sizes of laser spot radius, the thermal conductivity κ and the interface thermal conductance g of the supported single-layer WS2 are determined as ∼32.8 ± 3.8 W/m·K and 4.4 ± 0.4 KW/m2·K simultaneously, respectively. Our research demonstrates that the micro-PL approach can be an effective contactless way to investigate the thermal transport properties of single- and few-layer TMDC materials.

Layered 2D MoSe2(1–x)Te2x Alloys: Promising Thermoelectric Material with Tunable Thermal and Electrical Transport

“…Raman spectroscopy is a very sensitive technique that can detect phonon frequency vibrations, and hence thermal conductivity values can be extracted from the Raman spectral data. 41,42 This method has been widely applied for various 2D materials such as graphene, phosphorene, MoS 2 , MoTe 2 , WS 2 , and other thin layers. 41−45 In this study, single crystals of MoSe 2(1−x) Te 2x with x values of 0 to 1 are grown and characterized by various techniques.…”

“…In addition, in order to minimize the thermal conductivity, it is essential to understand the phonon dynamics, particularly the electron–phonon and phonon–phonon interactions. Raman spectroscopy is a very sensitive technique that can detect phonon frequency vibrations, and hence thermal conductivity values can be extracted from the Raman spectral data. , This method has been widely applied for various 2D materials such as graphene, phosphorene, MoS 2 , MoTe 2 , WS 2 , and other thin layers. − …”

Multipurpose Poly(dimethylsiloxane) Dielectric Films with Superb Thermal Conductivity by Incorporating Silver Nanoparticle-Decorated Boron Nitride Nanosheets

“…Developing advanced thermal management materials (TMMs) is essential to alleviate the accumulation of heat in modern devices with high power and energy density, such as flexible power electronics, computer chips, electric vehicles, and 5G communication equipment. − Poly­(dimethylsiloxane) (PDMS) is a promising candidate for preparing TMMs by virtue of its lightweight, easy processing, as well as exceptional electric and mechanical characteristics. , Particularly, PDMS possess remarkably flexible and airtight properties, maintaining good intrinsic performance when subjected to stresses such as stretching and bending, which enable them to adhere perfectly to the device and thus accelerate heat dissipation. , However, owing to the low inherent thermal conductivity (λ, ∼0.2 W/m·K), PDMS shows insufficient heat dissipation capacity, which restricts its application in thermal management . Considerable effort has been dedicated to improving the λ of PDMS-based TMMs by incorporating highly thermally conductive fillers, such as ceramics (boron nitride, alumina, silicon carbide, etc.…”

“…5,6 Particularly, PDMS possess remarkably flexible and airtight properties, maintaining good intrinsic performance when subjected to stresses such as stretching and bending, which enable them to adhere perfectly to the device and thus accelerate heat dissipation. 7,8 However, owing to the low inherent thermal conductivity (λ, ∼0.2 W/m• K), PDMS shows insufficient heat dissipation capacity, which restricts its application in thermal management. 9 Considerable effort has been dedicated to improving the λ of PDMS-based TMMs by incorporating highly thermally conductive fillers, such as ceramics (boron nitride, alumina, silicon carbide, etc.…”

Uniaxial Strain-Induced Tunable Mid-infrared Light Emission from Thin Film Black Phosphorus

“…As a bridge two-dimensional (2D) material between graphene (zero bandgap) and transition metal dichalcogenides (TMDCs) , that exhibit visible luminescence, black phosphorus (bP) with a layered buckled structure has a tunable direct bandgap ranging from ∼2.0 eV (single layer) to ∼0.3 eV (bulk) . This property makes bP have a broadband optical response from the visible to mid-infrared region.…”