초록 |
In this study, three-dimensional (3D) graphene oxide/carbon nanotube (GO/CNT) foams were prepared by integrating GO sheets and CNTs from water-ethanol system via freezing and lyophilization without using any other materials. The GO sheets acted as a dispersing agent for carbon nanotubes in water and ethanol inhibited ice crystal growth at low temperature. Owing to the insertion of CNTs between GO layers, the prepared GO/CNT foam exhibited special characteristics, such as a sponge-like morphology and unique textural properties. The GO/CNT foam could be reduced by thermal treatment without deformation, resulting in electrically conductive graphene-based foams. Furthermore, a supercapacitor consisting of the reduced foam as electrodes and GO membrane as separator was fabricated. The resultant supercapacitor showed distinctive electrochemical behaviors including high rate capability and cycle behavior because the unique structure of the foam led to rapid electrolyte ion diffusion. |