Synthesis and physicochemical properties of graphene/ZrO₂ composite aerogels

Aerogel materials possess a wide variety of exceptional properties, including a quite low density, high specific surface area, high porosity, etc. Considering that both graphene aerogels and ZrO₂ aerogels have advantages and disadvantages respectively, graphene/ZrO₂ composite aerogels are prepared, by a facile step, to enable them to have low thermal conductivity and to enhance the electronic interaction between the ZrO₂ nanoparticles and graphene sheets. The chemical composition and crystalline structure of the resulting graphene/ZrO₂ composite aerogels, as well as the strong interaction between the graphene sheets and the ZrO₂ nanoparticles, have been disclosed by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and X-ray powder diffraction (XRD). The morphology and hierarchically porous attributes of the resulting graphene/ZrO₂ composite aerogels have been investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption-desorption tests. The mechanical properties, electrical conductivity, electrochemical properties and thermal conductivity (as well as thermal stability) of the resulting graphene/ZrO₂ composite aerogels have also been revealed in this study.