Heat Transfer at the Interface of Graphene Nanoribbons with Different Relative Orientations and Gaps

Abstract

Because of their high thermal conductivity, graphene nanoribbons (GNRs) can be employed as fillers to enhance the thermal transfer properties of composite materials, such as polymer-based ones. However, when the filler loading is higher than the geometric percolation threshold, the interfacial thermal resistance between adjacent GNRs may significantly limit the overall thermal transfer through a network of fillers. In this article, reverse non-equilibrium molecular dynamics is used to investigate the impact of the relative orientation (i.e., horizontal and vertical overlap, interplanar spacing and angular displacement) of couples of GNRs on their interfacial thermal resistance. Based on the simulation results, we propose an empirical correlation between the thermal resistance at the interface of adjacent GNRs and their main geometrical parameters, namely the normalized projected overlap and average interplanar spacing. The reported correlation can be beneficial for speeding up bottom-up approaches to the multiscale analysis of the thermal properties of composite materials, particularly when thermally conductive fillers create percolating pathways.

Nanoporous graphene: A 2D semiconductor with anisotropic mechanical, optical and thermal conduction properties

“…The NEMD simulations were conducted using the LAMMPS [72] package along with the AIREBO [73] force-field to introduce the atomic interactions. In the all NEMD simulations, we applied periodic boundary condition along the planar directions and a relatively small time increment of 0.25 fs was used to count for the high vibrations of H atoms [74][75][76][77][78]. The NEMD calculations were performed for NPG monolayers with different lengths to investigate the length effect on the predicted thermal conductivities.…”

Mesoscopic Modeling and Experimental Validation of Thermal and Mechanical Properties of Polypropylene Nanocomposites Reinforced By Graphene-Based Fillers

“…The thermal conductivity of the PP composite material increases with the weight percentage of graphene fillers in all cases, with CG-MD predictions showing lower enhancement because thermal boundary resistances at the filler–filler and filler–matrix interfaces are duly considered in this model while being neglected by continuum ones. 81 , 82 …”

“…The thermal conductivity of the PP composite material increases with the weight percentage of graphene fillers in all cases, with CG-MD predictions showing lower enhancement because thermal boundary resistances at the filler−filler and filler−matrix interfaces are duly considered in this model while being neglected by continuum ones. 81,82 To include the effect of thermal boundary resistance also in continuum approaches, Shahil and Balandin 83 proposed a modified Maxwell−Garnett Effective Medium Approximation (MG-EMA) incorporating an interphase with thermal properties dictated by the Kapitza resistance at the interface between epoxy and graphene, also considering the effect of size and aspect ratio of fillers (see eq 1 in ref 83 for details). In the realm of predicting effective properties of composite materials, including the effective thermal conductivity, MG-EMA stands out as a widely employed approach.…”

Ultrafast nano generation of acoustic waves in water via a single carbon nanotube

“…Methodologically, we adopt a multiphysics, multiscale approach, a strategy that has been shown as very effective in addressing ultrafast opto-thermal [32] , [33] and opto-acoustic [34] , [35] , [36] transients in nano to mesoscale systems. In this work, the fact that water infiltrates the CNT or not and the thermal boundary conductance (TBC) between the CNT and water, a key quantity ruling the dynamics, are obtained from atomistic simulations [37] , [38] . The impulsive opto-thermo-mechanical dynamics is then cast in the frame of a continuum model, upon insertion of the geometrical and thermal microscopic parameters, and solved via Finite Element Methods (FEM).…”