Reduced graphene oxide based composite aerogels for energy storage and transportation of methane

Abstract

Aerogel based on reduced graphene oxide was synthesized using supercritical methods of drying the hydrogel in isopropanol. The synthesis technique involves the deposition of iron hydroxides on graphene layers, then their reduction in supercritical isopropyl alcohol to iron oxides (Fe3O4 and γ-Fe2O3). Results revealed that synthesized adsorbents Graphene aerogel (GA) and GA/Fe show excellent high gravimetric methane adsorption with an achievable capacity of 2.5 g/g and 3.6 g/g, respectively, in the pressure range of 0.5–10 MPa and 298 K, which is more than seven times higher than the requirements established by the US Department of Energy for the gravimetric capacity of a porous material for methane storage. However, at high gravimetric absorption, the volume absorption was 104 m3 (STP)/m3 and 102 m3 (STP)/m3 for (GA) and (GA/Fe), respectively. It should be noted that the performance characteristics of aerogels, in general, are comparable to adsorbents of other classes.