Novel Preparation of Reduced Graphene Oxide–Silver Complex using an Electrical Spark Discharge Method

Abstract

This study used an electrical discharge machine (EDM) to perform an electrical spark discharge method (ESDM), which is a new approach for reducing graphene oxide (GO) at normal temperature and pressure, without using chemical substances. A silver (Ag) electrode generates high temperature and high energy during gap discharge. Ag atoms and Ag nanoparticles (AgNP) are suspended in GO, and ionization generates charged Ag+ ions in the Ag plasma with a strong reducing property, thereby carrying O away from GO. A large flake-like structure of GO was simultaneously pyrolyzed to a small flake-like structure of reduced graphene oxide (rGO). When Ag was used as an electrode, GO was reduced to rGO and the exfoliated AgNP surface was coated with rGO, thus forming an rGOAg complex. Consequently, suspensibility and dispersion were enhanced.

Parameters and properties for the preparation of Cu nanocolloids containing polyvinyl alcohol using the electrical spark discharge method

“…The ESDM, which is frequently used in precision processing, can also be applied to nanocolloid preparation. [28][29][30] The principle is to use a minimal electrode distance and the energy generated by high-electricity fields to achieve an electric field intensity greater than the dielectric strength, causing a dielectric fluid breakdown. The passage of electricity through the two circuits generates a spark discharge that converts electricity to heat and generates high temperatures for component melting and for the removal of the component surface materials.…”

Parameter control and property analysis in the preparation of platinum iodide nanocolloids through the electrical spark discharge method

“…This method can also be implemented in nanocolloid preparation. 19,20 This involves generating spark discharge through the energy generated in a strong electric eld when the distance between the two electrodes is adequately short, converting the electrical energy to thermal energy of 5000-6000 K 21 and using it to melt the workpiece and remove the material from its surface. Fig.…”

Preparing Cuprous Iodide Nanocolloid by the Electrical Spark Discharge Method

“…A highfrequency pulse voltage is generally applied to the electrodes. When the gap between the electrodes is 30 lm [17,18], the electric field between the two electrodes increases slightly, and the electric field force is at its strongest at this time. The difference in potential between the two electrodes results in electric sparks, which dissociate the surface of the metal or nonmetal electrode [19].…”