Heat transfer through hydrogenated graphene superlattice nanoribbons: a computational study

Abstract

Optimization of thermal conductivity of nanomaterials enables the fabrication of tailor-made nanodevices for thermoelectric applications. Superlattice nanostructures are correspondingly introduced to minimize the thermal conductivity of nanomaterials. Herein we computationally estimate the effect of total length and superlattice period ($$l_{p}$$ l p ) on the thermal conductivity of graphene/graphane superlattice nanoribbons using molecular dynamics simulation. The intrinsic thermal conductivity ($$\kappa_{\infty }$$ κ ∞ ) is demonstrated to be dependent on $$l_{p}$$ l p . The $$\kappa_{\infty }$$ κ ∞ of the superlattice, nanoribbons decreased by approximately 96% and 88% compared to that of pristine graphene and graphane, respectively. By modifying the overall length of the developed structure, we identified the ballistic-diffusive transition regime at 120 nm. Further study of the superlattice periods yielded a minimal thermal conductivity value of 144 W m−1 k−1 at $$l_{p}$$ l p = 3.4 nm. This superlattice characteristic is connected to the phonon coherent length, specifically, the length of the turning point at which the wave-like behavior of phonons starts to dominate the particle-like behavior. Our results highlight a roadmap for thermal conductivity value control via appropriate adjustments of the superlattice period.

Efficient modulation of thermal transport in two-dimensional materials for thermal management in device applications

“…Many other studies have also demonstrated the size effect of graphene from experiments 47,147,148 and theoretical calculations. 107,149–152…”

“…Many other studies have also demonstrated the size effect of graphene from experiments 47,147,148 and theoretical calculations. 107,[149][150][151][152] Fig. 6 As for width dependence, considering a fixed length, the κ value is limited only by edge roughness.…”

“…10(a), because of the vibrational scattering and band anti-crossing induced by the combination of resonant phonon localization effects. 256 And both oxidate and hydrogenate of graphene reduce the κ due to the introduction of dramatic structure deformation, 152,[257][258][259] as shown in Fig. 10(b).…”

Effect of Graphene Diameter on Heat Transfer Pathways in Graphene/PVDF Nanocomposite Membranes

“…Graphene, featuring a two-dimensional honeycomb lattice structure of carbon atoms, possesses chemical inertness, high strength, and excellent electrical and thermal conductivity. − The unique phonon mode of reduced graphene oxide (RGO) demonstrates exceptional thermal conductivity. − Despite facing challenges associated with multiple influencing factors, the study of the thermal conductivity of microscopic sizes requires refinement, and improvements have yet to be made to the theory of heat transport. In preparing a graphene oxide (GO)/modified CNTs foam system, Lv employed a hydrothermal reaction.…”