Fractal characterization of graphene oxide nanosheet

Graphene oxide (GO) nanosheets of planar flake-like structures are fabricated by using a modified Hummers method. Fractal theory is introduced to characterize the topological surfaces and porous structures of the GO nanosheets, the fractal dimensions estimated by using box-counting method are close to 2, indicating that the GO nanosheets possess perfectly smooth surfaces, which agrees well with high resolution transmission electron microscopy (HRTEM) images, and the higher porous fractal dimension of 2.74 determined by using Frenkel-Halsey-Hill (FHH) model suggests a wealth of microporous structures of the GO nanosheets.