Parameter control and concentration analysis of graphene colloids prepared by electric spark discharge method

Abstract

In this study, graphene colloids were prepared using the electric spark discharge method (ESDM) with graphite rods (99.9% purity) in deionized water (DW) at a normal temperature and pressure. Five different types of graphene colloids were prepared using an electrical discharge machine (EDM) with five different pulse cycle switching times (Ton:Toff ) = 10:10, 30:30, 50:50, 70:70, and 90:90 μs. According to the Ultraviolet-visible spectra (UV-Vis) and Zetasizer analysis, the results showed that the 10:10 μs parameter was the most suitable for the preparation of graphene colloids. UV-Vis was also used to detect the concentration of the graphene colloids; a comparison with a graphene oxide (GO) confirmed that this method could be used to calculate the discharge time needed to produce graphene colloids with different concentrations in the ESDM process.

Research on the interface properties and strengthening–toughening mechanism of nanocarbon-toughened ceramic matrix composites

“…Therefore, favourable nanocarbon dispersion in the ceramic matrix is fundamental to obtaining excellent mechanical properties. Although nanocarbons with good dispersion can be obtained by [47] optimizing the preparation process, Kuo-Hsiung Tseng et al prepared the graphene with good dispersion by controlling the parameter of ESDM [34], further treatment is needed to play a better role in strengthening and toughening the ceramic substrate. In previous research, Ian A. Kinloch et al summarised four dispersion methods based on the combination mode between CNT/graphene and functional groups: π-π interactions, chemical bonding, as van der Waals forces and electrostatic interactions (as shown in Figure 1) [47].…”

Synthesis of graphene: Potential carbon precursors and approaches

“…A variant of electrochemical exfoliation, the electric spark discharge method [83], allows varying the pulse cycle switching times in order to manipulate the suspension properties of the graphene. There is still a major limitation to this synthesis as supplying an unbroken voltage bias to the graphite is difficult, and failure leads to irregular exfoliation, which becomes even more pronounced during scale-up owing to the larger areas of exposed graphite edges [84].…”

In-situ synthesis of Fe2O3/rGO using different hydrothermal methods as anode materials for lithium-ion batteries

“…Today's society is ushering in the rapid development of composite materials [3][4][5], especially composite materials used in electrochemistry have been widely manufactured in order to improve the conductivity of polymer composite materials [6]. Due to the special two-dimensional structure of graphene [7,8], graphene-based composite materials with a "surface-to-surface" electrical contact mode are recognized as the mode that can maximize the advantages of graphene [9][10][11]. And the research of graphene for battery load is gradually increasing [12].…”