With the increasing integration of devices in electronics fabrication, there are growing demands for thermal interface materials (TIMs) with high through-plane thermal conductivity for efficiently solving thermal management issues. Graphene-based papers consisting of a layer-by-layer stacked architecture have been commercially used as lateral heat spreaders; however, they lack in-depth studies on their TIM applications due to the low through-plane thermal conductivity (<6 W m-1 K-1). In this study, a graphene hybrid paper (GHP) was fabricated by the intercalation of silicon source and the in situ growth of SiC nanorods between graphene sheets based on the carbothermal reduction reaction. Due to the formation of covalent C-Si bonding at the graphene-SiC interface, the GHP possesses a superior through-plane thermal conductivity of 10.9 W m-1 K-1 and can be up to 17.6 W m-1 K-1 under packaging conditions at 75 psi. Compared with the current graphene-based papers, our GHP has the highest through-plane thermal conductivity value. In the TIM performance test, the cooling efficiency of the GHP achieves significant improvement compared to that of state-of-the-art thermal pads. Our GHP with characteristic structure is of great promise as an inorganic TIM for the highly efficient removal of heat from electronic devices.
Keywords: graphene hybrid paper; hierarchical structure; silicon carbide nanorods; thermal interface materials; through-plane thermal conductivity.