0000000000288653
AUTHOR
Jussi Kauppila
Electrochemical reduction of graphene oxide films in aqueous and organic solutions
Abstract Electrochemical reduction of graphene oxide (GO) films cast on tin oxide glass substrates were carried out in aqueous solutions and in propylene carbonate and acetonitrile. Cyclic voltammetric measurements indicate successful reduction of GO films. The reduction process begins in aqueous solutions at less negative potentials than in organic solutions. Additionally the pH value of the aqueous solutions influences the reduction potential. According to spectroscopic analysis the reduction process of the GO film can be controlled by the choice of reduction potential and electrolyte medium. The potential window in this work was made broader by increasing pH or by using organic electroly…
In situ FTIR and Raman spectroelectrochemical characterization of graphene oxide upon electrochemical reduction in organic solvents
Electrochemical reduction of solution cast and self-assembled graphene oxide (GO) films on Au surfaces were studied using organic solvents. During the cyclic voltammetry measurements the structural changes in the films were recorded focusing on in situ infrared and Raman techniques. Both FT-Raman and dispersive Raman spectroscopy were utilized for the reduction studies. The spectroelectrochemical results indicate that the changes in the GO structure take place in a quite narrow potential range extending from -1 to -1.7 V. Higher negative potentials gives rise to reversible changes in the spectra and are not due to reduction processes of GO but more related to changes in the electrolyte medi…
Electrochemical reduction of graphene oxide and its in situ spectroelectrochemical characterization
The electrochemical properties of self-assembled films of graphene oxide (GO) on mercaptoethylamine (MEA) modified rough Au-surfaces were studied. The film deposition process on MEA primed gold was followed by surface plasmon resonance measurements and the film morphology on 3-aminopropyltriethoxysilane primed Si(100)-surface was studied by atomic force microscopy. The deposited few layer thick GO films on gold were electrochemically reduced by cyclic voltammetry simultaneously as the structural changes in the film were recorded by in situ vibrational spectroscopies. In situ surface enhanced infrared spectroscopy results indicate that the effect of the applied potential on the GO structure …
Effective low temperature reduction of graphene oxide with vanadium(iii)
Reduction of graphene oxide (GO) with vanadium(III) trichloride under various reaction conditions has been investigated. The results show that V(III) can be used as an efficient reducing agent for GO in aqueous solutions at low concentrations and in moderate temperatures under ambient conditions. The IR spectroscopy and X-ray photoelectron spectroscopy (XPS) show that the structure of the vanadium-reduced material is similar to reduced graphene oxide prepared using TiCl3 or hydrazine as a reducing agent. The electrical conductivity of the material is also similar in all cases. However, on the basis of the XPS results, vanadium-based reduction does not leave significant reductant impurities …