Flatness-dependent thermal conductivity of graphene-based composites

Since the graphene nanoplates (GNPs) are usually folded and wrinkled, we propose a factor, flatness ratio, to theoretical analyze the thermal conductivity of GNP composites. An analytical model for the thermal conductivity of GNP composites is presented, which shows an excellent agreement with the experimental data. Theoretical analysis reveals that flatness ratio acts as a dominant role in determining the influence of other factors. We further show that the two-dimensional geometry is the primary factor for GNP outperforming one-dimensional carbon nanotubes as thermal conductive filler, rather than the other factors of thickness, length and interfacial thermal resistance. (C) 2013 Elsevier B.V. All rights reserved.