Highly potent radical scavenging-anti-oxidant activity of biologically reduced graphene oxide using Nettle extract as a green bio-genic amines-based reductants source instead of hazardous hydrazine hydrate

The high cohesive interaction between reduced graphene oxide (RGO) sheets usually makes them difficult to disperse, which limits their utilization in achieving effective hybridization with polymers. We report here a new two-step route for preparing non-aggregated and high-conductive RGO powders. Graphene oxide precursor was first reduced by hydrazine hydrate in presence of a thermal unstable surfactant of cetyltrimethylammonium chloride (CTAC). Then a thermal annealing process under H2/Ar atmosphere was further used to remove the non-conductive CTAC molecules. The prepared RGO powder exhibited an electrical conductivity of 2.23 × 104 S m−1 – about ten times higher than the one (N-RGO) simply reduced by hydrazine hydrate. After incorporating into polymethylmethacrylate with a 5 wt% loading, the composite showed a conductivity of 4.11 S m−1, which was 60 times as high as that of the same composite based on N-RGO powder. The addition and subsequent removal of CTAC molecules is an effective method for preparing non-aggregated and highly conductive graphene powder and obtaining good incorporation into polymer matrices.

Download Full-text

Modified Reduced Graphene Oxide with Enhanced Solubility and Conductivity and its Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.989-994.859 ◽

2014 ◽

Vol 989-994 ◽

pp. 859-862

Author(s):

Xiao Peng Zeng

Keyword(s):

Graphene Oxide ◽

Hydrazine Hydrate ◽

Reduced Graphene Oxide ◽

Phenyl Isocyanate ◽

Functionalized Graphene ◽

Step Method ◽

Reduced Graphene ◽

Enhanced Solubility ◽

Modified Graphene ◽

Additional Reduction

Graphene oxide was modified with phenyl isocyanate first, and then reduced by a two step method-reduction with hydrazine hydrate first and an additional reduction in H2/Ar. The reduction with hydrazine hydrate in the first step can effectively remove the epoxy groups on the graphene, and the disposure of reduced graphene oxide (RGO) with H2 will change the residual amides and carbamate esters into conjugated C=N-ph structure. The introduced phenyl isocyanate not only acts as a functionalized group to prevent the aggregation of graphene but also will increase the electron concentration because of additional benzene. The resulted functionalized graphene can well dispersed in DMF, and the electrical conductivity of the functionalized graphene can reach 3.42×104S/m,which is far high than the method only reduce with the chemical reductant or H2/Ar. The prepared functionalized graphene is beneficial for the fabrication of graphene-based polymer nanocomposites. The conductivity of resulted modified graphene/PMMA composite with 5wt% filler content is 3.2S/m.

Download Full-text

A polyaniline/graphene nanocomposite prepared by in situ polymerization of polyaniline onto polyanion grafted graphene and its electrochemical properties

RSC Advances ◽

10.1039/c3ra46832a ◽

2014 ◽

Vol 4 (15) ◽

pp. 7673-7681 ◽

Cited By ~ 8

Author(s):

Tao Wu ◽

Xiaoyang Xu ◽

Lei Zhang ◽

Huabin Chen ◽

Jianping Gao ◽

...

Keyword(s):

Graphene Oxide ◽

Electrochemical Properties ◽

Hydrazine Hydrate ◽

Reduced Graphene Oxide ◽

Radical Polymerization ◽

In Situ Polymerization ◽

Reduced Graphene ◽

Graphene Nanocomposite

Poly(sodium 4-styrensulfonate), a polyanion, was grafted onto reduced graphene oxide (RGO-g-PSSNa) by in situ radical polymerization and was then chemically reduced with hydrazine hydrate.

Download Full-text