Progress in preparation, characterization, surface functional modification of graphene oxide: A review

Graphene oxide (GO) has become the focus of scientific research due to unique mechanical, optical, electrical and chemical properties. We review the synthesis approaches and formation mechanism of GO, and propose that the crucial factor to the preparation of GO is to find efficient and environmentally friendly oxidant. Various characterization techniques are introduced, and characteristics are summarized. The GO model theories are synopsized, and determining the structure of GO has important influence on its surface modification and its application and development in composite materials. The interaction and reaction types between GO matrix and modified molecules, as well as the properties of modified products were described. In conclusion, the present challenges and future research directions are presented in terms of preparation and surface functional modification for GO.