Polyimide-based composite carbon film with high thermal conductivity and preparation method therefor

Disclosed in the present invention are a polyimide-based composite carbon film with high thermal conductivity and a preparation method therefor. The method comprises: uniformly coating the surface of a polyimide-based carbon film with an aqueous graphene oxide solution, and then covering same with another polyimide-based carbon film that is uniformly coated with the aqueous graphene oxide solution; repeating the operation; and after drying, bonding the polyimide-based carbon films by means of graphene oxide to form a thick film. By means of further low-temperature hot-pressing, the polyimide-based carbon films are bonded more tightly; and finally, a polyimide-based thick carbon film with high thermal conductivity can be obtained by repairing defects by means of low-temperature heating pre-reduction and high-temperature and high-pressure thermal treatment. The thickness of the polyimide-based thick carbon film with high thermal conductivity is greater than 100 μm, and the in-plane thermal conductivity thereof can even reach 1700 W/mK or above, so that the polyimide-based composite carbon film has a relatively great application prospect in a high-frequency high-heat-flux devices.