Thermal Properties of Graphene: Applications in Thermal Interface Materials

We review results of the thermal conductivity studies of graphene, which revealed its excellent heat conduction properties. Using the liquid solutions of graphene and few-layer graphene flakes, we produced composites with graphene as the filler material. The measurements of thermal properties of the resulting graphene composites have been measured with the "laser flash" and transient planar-source "hot disk" techniques. We have demonstrated that graphene flakes can substantially increase the effective thermal conductivity of the composite materials even at small volume loading fractions. The thermal conductivity enhancement exceeded a factor of five at 5% of the volume loading fraction and reached a factor of ten for some specific composites. We argue that graphene and few-layer graphene flakes can become efficient fillers for the thermal interface materials.