In this study, we report an inexpensive, massively scalable, fast, and facile method for preparation of graphene oxide and reduced graphene oxide nanoplatelets. The basic strategy involved the preparation of graphite oxide (GO) from graphite through reaction with benzoyl peroxide (BPO), complete exfoliation of GO into graphene oxide sheets, followed by their in situ reduction to reduced graphene oxide nanoplatelets. The mechanism of graphene oxide producing is mainly the generation of oxygencontaining groups on graphene sheets. In addition, inserted BPO and expansion of CO 2 evolved during reaction will expand the distance between graphite layers, which are also main factors for exfoliation. Thermogravimetric analysis, Raman spectroscopy, and Fourier transform infrared spectroscopy indicated the successful preparation of GO. X-ray diffraction proved the mechanism of intercalation and exfoliation of graphite. Transmission electron microscopy and atomic force microscopy were used to demonstrate the structure of produced graphene oxide and reduced graphene oxide nanoplatelets.

An in situ chemical synthesis approach has been employed to prepare an Ag-chemically converted graphene (CCG) nanocomposite. The reduction of graphene oxide sheets was accompanied by generation of Ag nanoparticles. The structure and composition of the nanocomposites were confirmed by means of transmission electron microscopy (TEM), atomic force microscopy (AFM) and X-ray diffraction. TEM and AFM results suggest a homogeneous distribution of Ag nanoparticles (5-10 nm in size) on CCG sheets. The intensities of the Raman signals of CCG in such nanocomposites are greatly increased by the attached silver nanoparticles, i.e., there is surface-enhanced Raman scattering activity. In addition, it was found that the antibacterial activity of free Ag nanoparticles is retained in the nanocomposites, which suggests they can be used as graphene-based biomaterials.

Between the sheets: Polystyrene–polyacrylamide copolymer is covalently grafted onto graphene sheets by in situ living free‐radical polymerization to give “amphiphilic” graphene nanoplatelets. The block copolymer disperses graphene nanoplatelets in a polar solvent (water; see picture, A versus C) and also stabilizes them in a nonpolar solvent (xylene; B versus D).

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In this study, graphene oxide-magnetic nanoparticle composites were prepared by attaching magnetic nanoparticles to graphene oxide through a high temperature reaction of ferric triacetylacetonate with graphene oxide in 1-methyl-2-pyrrolidone. X-ray diffraction, transmission electron morphology, and thermogravimetric analysis were used to demonstrate the successful attachment of iron oxide nanoparticles to graphene sheets. It was found that the attached nanoparticles were mainly magnetite. Investigations using Fourier transform infrared spectroscopy proved that the tight attachment was due to the robust linkage: metal-carbonyl coordination.