In situ growth of graphitic carbon nitride on multiwalled carbon nanotubes for interfacial thermal management

This work reports a facile method for in situ growth of graphitic carbon nitride (CN) on surface of multiwalled carbon nanotubes (CNTs), which was performed via the self-assembly of molecular precursors of CN on CNTs and subsequent calcination step. The self-assembly was directed by the hydrogen bonds formed between amino groups of Melamine and carboxyl units of CNTs. After polycondensation reaction, CN nanostructures grew homogeneously on surface of CNTs possibly linked by covalent bonds. The incorporation of CN improved the interfacial properties of CNTs by increasing the functional groups and wettability, which could promote the dispersion of CNTs in polymer matrix and enhance the heat conductive capacity. Accordingly, the obtained thermal conductive silicon grease involving CNTs/CN nanocomposites showed an enhancement in thermal conductivity at a loading amount of CN (~ 8%). Meanwhile, the insulation resistance of the nanocomposites increased significantly with the dose amount of CN due to its semi-conductivity. Therefore, the obtained CNTs/CN nanocomposites were suitable for interfacial thermal management that require high thermal conductivity and electrically insulative properties.