Gamma-ray irradiation-induced reduction and self-assembly of graphene oxide into three-dimensional graphene aerogel

Three-dimensional (3D) graphene aerogel (GA) with honeycomb-like porous structure and high C/O ratio was successfully prepared from graphene oxide (GO) dispersions in isopropanol/water solution by simple gamma-ray irradiation and freeze-drying processes. Under irradiation, GO sheets suspending in the mixture were reduced and self-assembled mainly due to the restoration of pi-pi conjugated structure. The microstructure of GA was observed under different magnifications and the pores are quite uniform with pore size around 10 mu m. The reduction effect of GO was confirmed comprehensively by different characterizations. Briefly, gamma-ray irradiation is an effective and green method for the reduction and self-assembly of GO sheets. (C) 2016 Elsevier B.V. All rights reserved.