Extremely high thermal conductivity of nanodiamond-polydopamine/thin-layer graphene composite films

The experimental results show that the addition of dopamine results in dense structure of the ND-pDA/rGO hybrid films, which is favorable for phonon transport, and thus remarkably increase the thermal properties of the film. Additionally, films with higher ND-pDA loading possess lower in-plane but higher through-plane thermal conductivity. K// and K⊥ of 1406 and 0.677 W m−1 K−1, respectively, for 20ND-pDA/20rGO measured at 25 °C are achieved. Both the K// and K⊥ of 20ND-pDA/20rGO increase with test temperature. Maintaining such high thermal conductivities at high temperature, the hybrid films are believed to be suitable for lightweight thermal management materials with high heat transfer properties in a specific direction.