Phenylamine-Functionalized Graphene–Copper Composites with High Thermal Conductivity: Implications for Thermal Dissipation

Developing highly efficient thermal management techniques is crucial in order to achieve the best performance of electronic equipment. Here, a delocalized conjugated system was established by the conjugation of sp2 orbitals in phenylamine groups and a delocalized big π bond in graphene to construct an electron thermal conduction route. Then, the abundant π electrons in graphene can be transferred to the adjacent copper unimpededly, leading to a remarkable thermal conductivity. These results demonstrate that the copper substrate deposited with phenylamine-functionalized graphene (PA–Gr–Cu) shows a high thermal conductivity of 506 W m–1 k–1, which is 30.8 and 44.2% higher than those of the pristine graphene–copper composite (Gr–Cu) and copper (Cu), respectively. Placed on a heat source heated from 30 to 210 °C within 5 min, the top surface temperature of PA–Gr–Cu increases to 198 °C rapidly, whereas those of Gr–Cu and Cu only increase gently to 88 and 59 °C. This work demonstrates that phenylamine with a pair of lone electrons in the N atom shows superiority as an intermediate molecule to link graphene and copper to establish a delocalized conjugated system. This innovation provides another solution to establish a conjugated structure between graphene and copper to construct an electron thermal conduction route with remarkable thermal conduction properties and will promote the research on the electron thermal conduction route for graphene-based metal matrix composites in the application of thermal dissipation.