Owing to the development of microelectronics, demands for excellent thermal dissipation materials have substantially increased. Learning from natural nacre, thermally conductive epoxy nanocomposites were prepared based on asymmetrically polydopamine-functionalized Janus graphene oxide (JPGO) scaffolds. The required highly oriented JPGO scaffolds were prepared via the bidirectional freeze-casting method. With the addition of epoxy resin, the resulting nanocomposite reveals anisotropic thermal properties. With the total content of the JPGO scaffold being 0.93 wt %, almost 35 times enhancement of in-plane thermal conductivity (perpendicular to the lamellar structure) (∼5.6 W m-1 K-1) has been obtained. The single-side-functionalized JPGO scaffolds play an important role in forming thermal conductive networks for the epoxy nanocomposites. Importantly, the nanocomposites present electrically insulating properties (>1014 Ω cm). Such high-performance nanocomposites have promising applications for thermal management in electronic devices.
Keywords: graphene oxide; nacre; polydopamine; thermal conductivity; thermal management.