Highly adsorptive graphene aerogel microspheres with center-diverging microchannel structures

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. Novel graphene oxide aerogel microspheres (GOAMs) with well-defined "center-diverging microchannel" structures are obtained by a novel approach, i.e. a combination of electrospraying and freeze-casting. A formation mechanism, i.e. radial-directional freezing-thawing, was proposed. The reduced GOAMs exhibit excellent adsorption ability for various organic liquids and oils due to their highly hierarchical hydrophobic structure and a random packing effect.