Width dependent intrinsic thermal conductivity of suspended monolayer graphene

This article demonstrates a dispersed-monolayer graphene-doped polymer/silica hybrid Mach–Zehnder interferometer (MZI) thermal optical switch with low-power consumption and fast response. The polymer/silica hybrid MZI structure reduces the power consumption of the device as a result of the large thermal optical coefficient of the polymer material. To further decrease the response time of the thermal optical switch device, a polymethyl methacrylate, doped with monolayer graphene as a cladding material, has been synthesized. Our study theoretically analyzed the thermal conductivity of composites using the Lewis–Nielsen model. The predicted thermal conductivity of the composites increased by 133.16% at a graphene volume fraction of 0.263 vol %, due to the large thermal conductivity of graphene. Measurements taken of the fabricated thermal optical switch exhibited a power consumption of 7.68 mW, a rise time of 40 μs, and a fall time of 80 μs at a wavelength of 1550 nm.

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Interfacial Thermal Conductance across Graphene/MoS2 van der Waals Heterostructures

Energies ◽

10.3390/en13215851 ◽

2020 ◽

Vol 13 (21) ◽

pp. 5851

Author(s):

Shuang Wu ◽

Jifen Wang ◽

Huaqing Xie ◽

Zhixiong Guo

Keyword(s):

Thermal Conductivity ◽

First Principles ◽

Van Der Waals ◽

Thermal Conductance ◽

Md Simulations ◽

Monolayer Graphene ◽

Density Of State ◽

Interfacial Thermal Conductance ◽

Van Der Waals Heterostructure ◽

Phonon Spectra

The thermal conductivity and interface thermal conductance of graphene stacked MoS2 (graphene/MoS2) van der Waals heterostructure were studied by the first principles and molecular dynamics (MD) simulations. Firstly, two different heterostructures were established and optimized by VASP. Subsequently, we obtained the thermal conductivity (K) and interfacial thermal conductance (G) via MD simulations. The predicted Κ of monolayer graphene and monolayer MoS2 reached 1458.7 W/m K and 55.27 W/m K, respectively. The thermal conductance across the graphene/MoS2 interface was calculated to be 8.95 MW/m2 K at 300 K. The G increases with temperature and the interface coupling strength. Finally, the phonon spectra and phonon density of state were obtained to analyze the changing mechanism of thermal conductivity and thermal conductance.

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The "intrinsic" thermal conductivity of some wet proteins in relation to their average hydrophobicity: Analyses on gels of egg-albumin, wheat gluten and milk casein.

Agricultural and Biological Chemistry ◽

10.1271/bbb1961.46.789 ◽

1982 ◽

Vol 46 (3) ◽

pp. 789-794 ◽

Cited By ~ 6

Author(s):

Jai-Yul KONG ◽

Osato MIYAWAKI ◽

KOZO NAKAMURA ◽

Toshimasa YANO

Keyword(s):

Thermal Conductivity ◽

Wheat Gluten ◽

Egg Albumin ◽

Milk Casein ◽

Intrinsic Thermal Conductivity

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Intrinsic Thermal Conductivity of Starch: A Model-independent Determination

Journal of Food Science ◽

10.1111/j.1365-2621.1993.tb04287.x ◽

1993 ◽

Vol 58 (2) ◽

pp. 413-415 ◽

Cited By ~ 11

Author(s):

TAKAHARU SAKIYAMA ◽

SOCKCHONG HAN ◽

N. SUSAN KINCAL ◽

TOSHIMASA YANO

Keyword(s):

Thermal Conductivity ◽

Independent Determination ◽

Model Independent ◽

Intrinsic Thermal Conductivity

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Ultra-Low Thermal Conductivity in Nanoscale Layered Oxides

Journal of Heat Transfer ◽

10.1115/1.4000052 ◽

2009 ◽

Vol 132 (3) ◽

Cited By ~ 13

Author(s):

J. Alvarez-Quintana ◽

Ll. Peralba-Garcia ◽

J. L. Lábár ◽

J. Rodríguez-Viejo

Keyword(s):

Thermal Conductivity ◽

Thermal Barrier Coatings ◽

Room Temperature ◽

Thermal Barrier ◽

Layered Oxides ◽

Barrier Coatings ◽

3Ω Method ◽

Nanometer Thickness ◽

Intrinsic Thermal Conductivity ◽

Strong Barrier

The cross-plane thermal conductivity of several nanoscale layered oxides SiO2/Y2O3, SiO2/Cr2O3, and SiO2/Al2O3, synthesized by e-beam evaporation was measured in the range from 30 K to 300 K by the 3ω method. Thermal conductivity attains values around 0.5 W/m K at room temperature in multilayer samples, formed by 20 bilayers of 10 nm SiO2/10 nm Y2O3, and as low as 0.16 W/m K for a single bilayer. The reduction in thermal conductivity is related to the high interface density, which produces a strong barrier to heat transfer rather than to the changes of the intrinsic thermal conductivity due to the nanometer thickness of the layers. We show that the influence of the first few interfaces on the overall thermal resistance is higher than the subsequent ones. Annealing the multilayered samples to 1100°C slightly increases the thermal conductivity due to changes in the microstructure. These results suggest a route to obtain suitable thermal barrier coatings for high temperature applications.

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Experimental Study on the Thermal Boundary Resistance Between an Individual Carbon Nanotube End and a Au Surface

Volume 10: Heat and Mass Transport Processes, Parts A and B ◽

10.1115/imece2011-62844 ◽

2011 ◽

Author(s):

Jun Hirotani ◽

Tatsuya Ikuta ◽

Takashi Nishiyama ◽

Koji Takahashi

Keyword(s):

Thermal Conductivity ◽

Experimental Study ◽

Carbon Nanotube ◽

Experimental Studies ◽

Boundary Resistance ◽

Thermal Boundary Resistance ◽

The Past ◽

Experiment Method ◽

Very High ◽

Intrinsic Thermal Conductivity

In the past decade, the very high intrinsic thermal conductivity of a carbon nanotube (CNT) has been successfully unveiled through experimental studies, but the thermal boundary resistance (TBR) between a CNT and ambient material still remains unclear. Some analytical and molecular dynamics studies have been reported on the TBR between a CNT and a surrounding material but there is no reliable experiment method to quantitatively investigate TBR between a CNT and a solid surface because of technical difficulties.

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