Interface thermal conductance and rectification in hybrid graphene/silicene monolayer

Journal of Applied Physics

Yang

Yue

2015

112

As the dimensions of nanocircuits and nanoelectronics shrink, thermal energies are being generated in more confined spaces, making it extremely important and urgent to explore for efficient heat dissipation pathways. In this work, the phonon energy transport across graphene and hexagonal boron-nitride (h-BN) interface is studied using classic molecular dynamics simulations. Effects of temperature, interatomic bond strength, heat flux direction, and functionalization on interfacial thermal transport are investigated. It is found out that by hydrogenating graphene in the hybrid structure, the interfacial thermal resistance (R) between graphene and h-BN can be reduced by 76.3%, indicating an effective approach to manipulate the interfacial thermal transport. Improved in-plane/out-of-plane phonon couplings and broadened phonon channels are observed in the hydrogenated graphene system by analyzing its phonon power spectra. The reported R results monotonically decrease with temperature and interatomic bond strengths. No thermal rectification phenomenon is observed in this interfacial thermal transport. Results reported in this work give the fundamental knowledge on graphene and h-BN thermal transport and provide rational guidelines for next generation thermal interface material designs.

Section: Introductionmentioning

confidence: 99%

Thermal transport across graphene and single layer hexagonal boron nitride

Journal of Applied Physics

Yang

Yue

2015

112

“…Using this approach, R between SiC and graphite is calculated to be B(1-7) Â 10 À10 K m 2 W À1 . 29 In traditional NEMD simulations, when a heat flux is constantly imposed on a group of atoms, the local temperatures in the heating/cooling areas are altered by variations of the atomic velocities. For 2D materials like graphene and silicene, the thermal resistance in the lateral direction can also be calculated by the NEMD method.…”

mentioning

confidence: 99%

Molecular dynamics study of interfacial thermal transport between silicene and substrates

Phys. Chem. Chem. Phys.

Yang

Tong

et al. 2015

In this work, the interfacial thermal transport across silicene and various substrates, i.e., crystalline silicon (c-Si), amorphous silicon (a-Si), crystalline silica (c-SiO2) and amorphous silica (a-SiO2) are explored by classical molecular dynamics (MD) simulations. A transient pulsed heating technique is applied in this work to characterize the interfacial thermal resistance in all hybrid systems. It is reported that the interfacial thermal resistances between silicene and all substrates decrease nearly 40% with temperature from 100 K to 400 K, which is due to the enhanced phonon couplings from the anharmonicity effect. Analysis of phonon power spectra of all systems is performed to interpret simulation results. Contradictory to the traditional thought that amorphous structures tend to have poor thermal transport capabilities due to the disordered atomic configurations, it is calculated that amorphous silicon and silica substrates facilitate the interfacial thermal transport compared with their crystalline structures. Besides, the coupling effect from substrates can improve the interface thermal transport up to 43.5% for coupling strengths χ from 1.0 to 2.0. Our results provide fundamental knowledge and rational guidelines for the design and development of the next-generation silicene-based nanoelectronics and thermal interface materials.

“…The effect of high‐TC fillers, such as graphene and BN, in improving the heat dissipation performance of TIMs is obvious, and some materials with similar 2D structures, such as silicene, and phosphorene, and 1D nanostructures, such as CNTs, have also been proven to have good thermophysical characteristics, which is advantageous for practical applications. In addition, some metal particles or nanowires (e.g., Ag, Cu, Al, etc.)…”

Section: New Methods To Control and Reduce The Itrmentioning

confidence: 99%

“…Hsieh et al observed that an increase in pressure can increase the interfacial stiffness at weak interfaces, which leads to an increase in the average phonon transmission coefficient and a lower ITR, but a clean Al–SiC interface (solid red circles in Figure b) is weakly dependent on the pressure . Moreover, the strong dependence of the ITR on pressure was interpreted as the Debye frequency increased and the PDOS of the contacting materials was extended, which created additional inelastic phonon channels and led to greater ITR . However, unlike previous studies, Gotsmann et al proposed a model that assumes quantum thermal transport across individual contact points to interpret the strong pressure dependence of the ITR and indicated that the number of contact points increases with pressure …”

Section: Factors Influencing the Itrmentioning

confidence: 98%

A Theoretical Review on Interfacial Thermal Transport at the Nanoscale

Yuan

Xiong

et al. 2017

Small

With the development of energy science and electronic technology, interfacial thermal transport has become a key issue for nanoelectronics, nanocomposites, energy transmission, and conservation, etc. The application of thermal interfacial materials and other physical methods can reliably improve the contact between joined surfaces and enhance interfacial thermal transport at the macroscale. With the growing importance of thermal management in micro/nanoscale devices, controlling and tuning the interfacial thermal resistance (ITR) at the nanoscale is an urgent task. This Review examines nanoscale interfacial thermal transport mainly from a theoretical perspective. Traditional theoretical models, multiscale models, and atomistic methodologies for predicting ITR are introduced. Based on the analysis and summary of the factors that influence ITR, new methods to control and reduce ITR at the nanoscale are described in detail. Furthermore, the challenges facing interfacial thermal management and the further progress required in this field are discussed.