Three-dimensional graphene-based aerogels prepared by a self-assembly process and its excellent catalytic and absorbing performance

A simple one-step method for fabricating graphene-based hydrogels (GHs) with interconnected 3D networks using Cu nanoparticles was developed. During this process, graphene oxide (GO) was reduced by Cu nanoparticles to form reduced GO (rGO) which then self-assembled to form GHs. Meanwhile, the Cu nanoparticles were oxidized to form copper(I) oxide which deposited onto the rGO sheets and became imbedded in the GHs. The GHs were transformed to graphene-based aerogels (GAs) by a green freeze-drying method. The composition of the GAs can be easily adjusted by simply changing the initial amount of Cu nanoparticles or the concentration of the GO suspension. The GAs not only possess good catalytic performance for the catalytic reduction of 4-nitrophenol and the photocatalytic degradation of methyl orange but also have excellent capacities for removing various oils and dyes from water.