Fengling Xia

A one-step method for reduction and self-assembling of graphene oxide into reduced graphene oxide aerogels

Reduced graphene oxide (rGO) aerogels were fabricated under mild conditions from an aqueous solution of graphene oxide (GO) using a one-step method which included the reduction of GO by mercaptoacetic acid and the self-assembling of rGO. The reduction of GO was confirmed with Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis and X-ray diffraction analysis. The elemental compositions of the GO and rGO aerogels were determined with X-ray photoelectron spectroscopy. The effect of different mercapto compounds on the assembly of rGO was investigated and the results showed that rGO can also accomplish self-assembling in water when mercaptoacetic acid and mercaptoethanol were used. The porous structure of the rGO aerogels was observed with scanning electron microscopy and their porosities were in the range of 90–96% when mercaptoacetic acid was used as the reductant. The high porosity gives the rGO aerogels excellent absorption abilities for metal ions.

Sn powder as reducing agents and SnO2 precursors for the synthesis of SnO2-reduced graphene oxide hybrid nanoparticles.

A facile approach to prepare SnO2/rGO (reduced graphene oxide) hybrid nanoparticles by a direct redox reaction between graphene oxide (GO) and tin powder was developed. Since no acid was used, it is an environmentally friendly green method. The SnO2/rGO hybrid nanoparticles were characterized by ultraviolet-visible spectroscopy, Raman spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The microstructure of the SnO2/rGO was observed with scanning electron microscopy and transmission electron microscopy. The tin powder efficiently reduced GO to rGO, and the Sn was transformed to SnO2 nanoparticles (∼45 nm) that were evenly distributed on the rGO sheets. The SnO2/rGO hybrid nanoparticles were then coated on an interdigital electrode to fabricate a humidity sensor, which have an especially good linear impedance response from 11% to 85% relative humidity.

Graphene oxide reduced and modified by environmentally friendly glycylglycine and its excellent catalytic performance

An environmentally friendly new approach to prepare reduced graphene oxide (RGO) was developed by using glycylglycine (glygly) as both a reducing and stabilizing agent. Graphene oxide (GO) was transformed to RGO with the appropriate pH, temperature and reducing agent/GO ratio. The RGO was characterized by ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, xray diffraction, xray photoelectron spectroscopy (XPS), and transmission electron microscopy. The RGO aqueous suspension showed extraordinary stability in the absence of any external stabilizing reagents. The XPS analysis showed that this excellent stability is due to modifications of the RGO nanosheets by the glygly molecules. The modified RGO complex with copper shows good catalytic performance for reduction of 4-nitrophenol to 4-aminophenol.