Thermal properties of graphene and multilayer graphene: Applications in thermal interface materials

We review the thermal properties of graphene and multilayer graphene, and discuss graphene’s applications in thermal management of advanced electronics and optoelectronics. A special attention is paid to the use of the liquid-phase-exfoliated graphene and multilayer graphene as the fillers in the thermal interface materials. It has been demonstrated that addition of an optimized mixture of graphene and multilayer graphene to the composites with different matrix materials produces the record-high enhancement of the effective thermal conductivity at the small filler loading fraction (f≤10 vol%). The thermal conductivity enhancement due to the presence of graphene in the composites has been observed for a range of matrix materials used by industry. The hybrid composites where graphene is utilized together with metallic micro- and nanoparticles allow one to tune both the thermal and electrical conductivity of these materials. Theoretical considerations indicate that the graphene-based thermal interface materials can outperform those with carbon nanotubes, metal nanoparticles and other fillers owing to graphene’s geometry, mechanical flexibility and lower Kapitza resistance at the graphene–base material interface.

► Graphene has extremely high intrinsic thermal conductivity.
► Small addition of the liquid-phase-exfoliated graphene can enhance thermal conductivity of composite materials.
► Composites with graphene and nanoparticles fillers can be both electrically insulating and conducting.
► Graphene composites are promising as thermal interface materials (TIMs).
► Thermal conductivity of graphene TIMs reveals weak temperature dependence—beneficial for thermal management applications.