Tailoring Thermal Transport Property of Graphene through Oxygen Functionalization

Abstract

We compute thermal conductivity of graphene oxide at room temperature with molecular dynamics simulation. To validate our simulation model, we have investigated phonon scattering in graphene due to crystal boundary length and isotope defect, both of which are able to diagnose the behavior of long wavelength and short wavelength phonon scattering. Our simulation shows that thermal conductivity of pristine graphene has logarithmic divergence for the boundary length up to 2 μm. As compared with pristine graphene, thermal conductivity of graphene oxide can be reduced by a factor of 25 at low oxygen defect concentration. Moreover, we find that not only the concentration but also the configuration of the oxygen functional groups (e.g., hydroxyl, epoxide, and ether) has significant influence on the thermal conductivity. Through phonon mode analysis, phonon defect scattering as well as phonon localization are mainly responsible for the conspicuous reduced thermal conductivity. The simulation results have provided fundamental insight on how to precisely control thermal property of graphene oxide for thermal management and thermoelectric applications.

Advanced multifunctional graphene aerogel – Poly (methyl methacrylate) composites: Experiments and modeling

“…As shown in Fig. 5, even with a much lower thermal conductivity of graphene (K rGO= 100 W/m K [85]) and a R bd of 1 · 10 À8 m 2 K/W, the estimated K eff is much higher than that found in experiments, and even higher than the simulated K eff of the composites with parallel-oriented graphene. This discrepancy between EMT results and experimental data may be attributed to the size effect of m-rGO sheets.…”

Thermal transport across graphene and single layer hexagonal boron nitride

“…[48][49][50] Thermal properties of hydrogenated graphene (H-GNR) and oxidized graphene (O-GNR) have been investigated by previous studies in seeks of better thermal management and thermoelectric applications. [51][52][53] In this work, the effects of hydrogenation on thermal transport across GNR/h-BN interfaces are studied. To keep consist with the previous calculations, dimensions of the heterostructure remain unchanged and the transient heating technique is applied.…”

Coherent and incoherent phonon thermal transport in isotopically modified graphene superlattices

“…The thermal transport properties of pristine graphene, [15][16][17][18][19][20] isotopically defected graphene [21][22][23][24][25] and functionalized graphene [26][27][28][29][30][31] have been widely studied. Graphene is well-known to have very weak Umklapp phonon scattering due to its two-dimensional phonon dispersion relation that makes satisfying scattering rules (energy and momentum conversion) difficult.…”