Super-elastic graphene/carbon nanotube aerogel: A novel thermal interface material with highly thermal transport properties

Three-dimensional (3D) graphene structure exhibits promising potential in thermal interface materials (TIMs) due to the continuous network structure and the high thermal conductivity of graphene. Nevertheless, the very low density and the high porosity of the 3D graphene monoliths usually lead to poor thermal transport performance. To overcome these problems, we fabricated the graphene/carbon nanotube (Gr/CNT) aerogels by a synergistic assembly strategy. The entangled CNTs bond the graphene sheets together to avoid the sliding of them under compression and greatly enhance the elastic stiffness of cell walls, which brings the aerogels super-elasticity. Bearing a high compression strain of 80%, the continuous thermal transport paths in Gr/CNT aerogels are still preserved. Significantly increased thermal conductivity of Gr/CNT aerogels can be obtained by directly mechanical compression. Meanwhile, the thermal transport properties of Gr/CNT aerogels can be further improved by elevating their initial density. With an initial density of 85 mg cm−3, a thermal conductivity up to 88.5 W m−1K−1 and a thermal interface resistance as low as 13.6 m m2KW−1 were obtained, which outperforms other carbon-based TIMs reported previously.