Graphene-Based Smart Thermal Conductive System Regulated by Reversible Pressure-Induced Mechanism
Thermal dissipation and thermal insulation are important for maintaining the normal operation of devices, extending the service life of instruments, ensuring the efficient energy utilisation, and improving the temperature-related human comfort.
Yet it is difficult to achieve both the functions of thermal dissipation and thermal insulation in a single material with a specific thermal conductivity under specific conditions. In this work, based on the huge difference in thermal conductivity between the air and the reduced graphene oxide (rGO), a pressure-induced mechanism is used to regulate the filling and elimination of air inside the rGO foam, and then the periodic reversible change of thermal conductivity is realised, which brings the achievement of dual functions of thermal dissipation and thermal insulation to meet the requirements of different application scenarios. Further fitting calculations suggest that the thermal conductivity of rGO foam is positively and negatively associated with the applied pressure and temperature, respectively, and it can be calculated through the given pressure and temperature conditions. The pressure-induced reversible regulation of thermal conductivity in the rGO foam provides a new design construct for the smart thermal-management devices, and a new direction of application for the 2D materials.