Enhanced thermal conductivity of graphene/polyimide hybrid film via a novel “molecular welding” strategy

With the development of high-power electronics and portable devices at a noticeable rate, thermal dissipation becomes challenging and critical to the performance of these devices. It greatly promotes the research and development of thermal dissipation materials. Due to its extremely high in-plane thermal conductivity, graphene have shown great potential in thermal management. In this work, a subtle “molecular welding” strategy was realized for the fabrication of flexible, ultrathin, but highly conductive graphitized-graphene/polyimide (g-GO/PI) hybrid films. PI was applied as a solder to weld the micron-sized graphene platelets up through the covalent bonding and to fill up the voids between the graphene layers. This is believed as the key to the considerable enhancement of the in-plane thermal conductivity of g-GO/PI hybrid films. It was worth noting that an enhancement of 21.9% in the in-plane thermal conductivity was achieved for the “molecular welded” g-GO/PI hybrid film as compared to the pristine g-GO film. The proposed “molecular welding” conception provides not only a promising way to the development of the next-generation graphene-based film for thermal management, but also an effective technique to fabricate functional materials with GO or graphene nanoplatelets in other fields.

Graphical abstractA novel “molecular welding” strategy was proposed to fabricate a flexible, ultrathin, but highly conductive graphene/polyimide (g-GO/PI) hybrid films. An enhancement of 21.9% in the in-plane thermal conductivity was achieved compared to the pristine graphene film. PI was applied as a solder to weld up the micron-sized graphene platelets through the covalent bonding. This is believed as the key to the considerable enhancement of the in-plane thermal conductivity of g-GO/PI hybrid films. Such a “molecular welding” conception provides a promising way to deliver the next-generation graphene-based film for thermal management.Download high-res image (250KB)Download full-size image