Highly adsorptive graphene aerogel microspheres with center-diverging microchannel structures

Abstract

The graphene oxide aerogel microspheres were prepared by a novel approach, i.e. a combination of electrospraying and freeze-casting. The unique well-defined “center-diverging microchannel” dandelion-like structures were observed in the aerogel microspheres and a formation mechanism of the structure, i.e. radial-directional freezing–thawing, was proposed. After further thermal reduction, the reduced graphene oxide aerogel microspheres were obtained and the center-diverging microchannel structures can be remained. Due to their highly porous, hierarchical and hydrophobic structure as well as a random packing effect, the aerogel microspheres possess excellent adsorption ability for various organic solvents and oils, showing their potential applications in environmental pollutant treatment.