Preparation of High Thermal Conductivity Graphene Films by Rapid Reduction with Low Energy Consumption

In the domain of smart electronic devices, graphene films play a pivotal role due to their flexibility and high thermal conductivity. Within the realm of fabricating highly thermally conductive graphene films, Joule heating technology has garnered significant attention because of its capability for rapid temperature elevation and reduction of graphitization duration. However, substantial gas emission occurs during the reduction of graphene oxide films using this method, leading to immediate combustion and film fracturing, thereby limiting the rapid and uninterrupted production of graphene films. To address this challenge, a rapid reduction preparation process is introduced. This process initiates with a two-step reduction of graphene oxide films employing a reducing agent to establish gas escape pathways within the graphene films beforehand. Subsequently, the film is pressurized and Joule-heated using a graphite plate, with the entire heating process lasting only 800 s. The resulting graphene film exhibits a remarkable thermal conductivity of up to 1012W/(m<middle dot>K). This method enhances the production efficiency of high thermal conductivity graphene films and is expected to further reduce production costs.