| dc.description.abstract | Synthesis of graphene is one of the best ways to value-add graphite. Electrochemical
exfoliation for graphene synthesis attracts interest due to its simplicity, cost-effectiveness,
and green approach compared to other methods. The limitation of electrochemical
exfoliation is restacking nature. One of the effective strategies to overcome this limitation
is the optimization of solvent parameters that critically affect the electrochemical exfoliation. Therefore, this study aims to optimize the electrochemical exfoliation for graphene
synthesis considering the Hansen solubility parameter of solvents to overcome restacking
of graphene layers. After optimizing the electrochemical exfoliation parameters, it was
applied for water and 5% N, N-dimethylformamide (DMF). Synthesized graphene was
characterized structurally and electrochemically in the presence of potassium ferricyanide.
Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray diffraction data
confirmed the formation of few-layer graphene. Scanning electron microscopic images
confirm the mean lateral size of graphene is in the nano-range. UV-visible data confirm the characteristic peak for graphene is around 268 - 274 nm, and the graphene
dispersibility is high in DMF. Cyclic voltammetry data illustrate the peak currents for
graphene/Nafion-modified glassy carbon (GC) electrodes, graphene-DMF, and graphene water, are 46.3 and 30.4 µA respectively compared to Nafion-modified GC electrode
which was 0.99 µA. Moreover, electrochemical impedance spectroscopy confirms the
high ion diffusion behavior of graphene-DMF-modified GC electrodes compared to other
electrodes. These characterization data confirm the favorable effect of solvents with
compatible Hansen solubility parameters such as DMF on the electrochemical exfoliation
and the potential of the novel strategy to easily synthesize graphene by manipulating
solvent properties. | |
