Comparative study of graphene aerogels synthesized using sol−gel method by reducing graphene oxide suspension

A graphene oxide aerogel synthesized from graphene oxide hydrogel and graphene aerogels have been synthesized using the sol−gel method by reducing a suspension of graphene oxide with various reducing agents: a mixture of hypophosphorous acid and iodine, L-ascorbic acid, sodium metabisulfite, and by hydrothermal treatment. The obtained aerogels have been studied by scanning electron microscopy, IR spectroscopy, Raman spectroscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Comparative studies of graphene aerogels have shown that their properties, namely density, specific surface area, reduction degree, surface morphology, defectiveness of graphene sheets, interlayer spacing, average sizes of coherent scattering regions, number of layers, and crystallite size in the basal plane in graphene crystallites depend on the method of synthesis.