We report that copper thin films deposited on top of graphene oxide (GO) serve as an effective catalyst to reduce GO sheets in a diluted hydrogen environment at high temperature. The reduced GO (rGO) sheets exhibit higher effective field-effect hole mobility, up to 80 cm(2) V(-1) s(-1), and lower sheet resistance (13 kΩ □(-1)) compared with those reduced by reported methods such as hydrazine an...

Graphene sheets have the potential for practical applications in electrochemical devices, but their development has been impeded by critical problems with aggregation of graphene sheets. Here, we demonstrated a facile and bottom-up approach for fabrication of DNA sensor device using water-soluble sulfonated reduced graphene oxide (SRGO) sheets via microwave-assisted sulfonation (MAS), showing e...

With a dramatic rise in complexity, needs of nanotoxicology research go beyond simple forms of nanomaterials. This study compared the phototoxicity of nano-TiO2 and graphene-TiO2 nanocomposite (GNP). GNP was synthesized based on a hydrothermal method, which simultaneously performed the reduction of graphene oxide and nano-TiO2 loading. A series of acute toxicity tests of nano-TiO2, graphene and...

Graphite oxide sheet, now referred to as graphene oxide (GO), is the product of chemical oxidation and exfoliation of graphite powders that was first synthesized over a century ago. Interest in this old material has resurged in recent years, especially after the discovery of graphene, as GO is considered a promising precursor for the bulk production of graphene-based materials. GO sheets are si...

The design of graphene-based materials for biomedical purposes is of great interest. Graphene oxide (GO) sheets represent the most widespread type of graphene materials in biological investigations. In this work, thin GO sheets were synthesized and further chemically functionalized with DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), a stable radiometal chelating agent, by an e...

We report a high-throughput method of generating graphene monolayer (>90% yield) from weakly oxidized, poorly dispersed graphite oxide (GO) aggregates. These large-sized GO aggregates consist of multilayer graphite flakes which are oxidized on the outer layers, while the inner layers consist of pristine or mildly oxidized graphene sheets. Intercalation-exfoliation of these GO aggregates by tetr...

Three-dimensional manganese oxide is directly grown on reduced graphene oxide (RGO) sheets, exhibiting comparable catalytic activity, higher selectivity and better stability towards oxygen reduction reaction than those of the commercial Pt/XC-72 catalyst.

A hybrid of holey graphene and Mn3O4 is prepared by a one-step process, in which the formation of a holey structure is accompanied with Mn3O4 nanoparticles through a high temperature reaction between graphene oxide sheets and KMnO4. Holey graphene and Mn3O4 collaboratively attributed to the enhanced catalytic activity and efficiency towards the oxygen reduction reaction.

Graphene oxide was synthesized by using modified Hummers method and also Graphene-NiO nanocomposite prepared by hydrothermal method with the use of graphene oxide solution, Ni(NO3)2•6H2O and urea as raw materials. The synthesized nanocomposite was characterized by the XRD, Raman, SEM, TGA and energy dispersive spectrometer analysis. The results demonstrate that NiO nano particles uniformly cove...

A controlled, reproducible, gram-scale method is reported for the covalent functionalization of graphene sheets by a one-pot nitrene [2+1] cycloaddition reaction under mild conditions. The reaction between commercially available 2,4,6-trichloro-1,3,5-triazine and sodium azide with thermally reduced graphene oxide (TRGO) results in defined dichlorotriazine-functionalized sheets. The different re...