Influence of parent graphite particle size on the electrochemistry of thermally reduced graphene oxide

Abstract

Electrochemical applications of graphene are of very high importance. For electrochemistry, bulk quantities of materials are needed. The most common preparation of bulk quantities of graphene materials is based on oxidation of graphite to graphite oxide and subsequent thermal exfoliation of graphite oxide to thermally reduced graphene oxide (TR-GO). It is important to investigate to which extent a reaction condition, that is, composition of the oxidation mixture and size of graphite materials, influences the properties of the resulting materials. We characterised six graphite materials with a range of particle sizes (0.05, 11, 20, 32, 35 and 41 μm) and the TR-GO products prepared from them by use of scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. Cyclic voltammetric performance of the TR-GO samples was compared using ferro/ferricyanide and ascorbic acid. We observed no correlation between size of initial graphite and properties of the resultant TR-GO such as density of surface defects, amount of oxygen-containing groups, or rate of heterogeneous electron transfer (HET). A positive correspondence between HET rate and high defect density as well as low amounts of oxygen functionalities was noted. Our findings will have profound influence upon practical fabrication of graphene for applications in sensing and energy storage devices.

Testing the influence of the temperature, RH and filler type and content on the universal power law for new reduced graphene oxide TPU composites

“…Oxidation and sonication processes may reduce the lateral size of rGO due to the break of the XY planes. [29]. In our case, no significant reduction of the lateral size, determined by laser diffraction or SEM, has been observed ( Table 1).…”

A Comprehensive Review on the Nanocomposites of Graphene and Its Derivatives in the Application of Supercapacitors

“…This technique provides a simple and effective process for extremely transparent and conductive graphene films. Preparation of huge amount of graphene materials is based on oxidation of graphite oxide graphite and exfoliation of graphite oxide thermally to TR-GO 37 . Six graphite materials were characterized in the series of particle sizes and TR-GO material products prepared by using scanning electron microscopy, Raman spectroscopy and photoelectron spectroscopy result indicated the absence of correlation between the length of the unique graphite and the nature of the resultant material of TR-GO, such as the densitysurface defects, the amount of oxygen-containing groups or the heterogeneous electronic transfer rate (HET).A positive match between the HET speed and the high density of defects, as well as a low amount of oxygen functionality.…”

Synthesis of graphene oxide–methacrylic acid–sodium allyl sulfonate copolymer and its tanning properties

“…The presence of these groups makes GONs hydrophilic, allowing them to be easily dispersed in water (Singh et al, 2011;Dreyer et al, 2010). These groups can be controlled effectively by adjusting oxidant composition and oxidization processing Chee et al, 2012). Single-layer GONs can be randomly bent and wrinkled, and multilayer GON aggregates can slide over each other.…”