Synthesis of Graphenic Carbon Materials on Nickel Particles with Controlled Quantity of Carbon

Abstract

A cheap, comparatively simple and effective method is proposed for the large quantity production of the sheets of graphenic carbon materials (GCM) by annealing the mixture of nickel powder with a suitable carbon amount at the temperatures close to 1000 ºC. The number of graphene layers in the sheets of GCM may be varied by altering the amount of carbon in the mixture and parameters of annealing and drying of the obtained products. Samples of GCM were prepared in the form of heat-dried GCM paper and in the form of graphene sponge with freeze-drying. The appearance of GCM on the surface of Ni particles was identified using a scanning electron microscope (SEM) at a low accelerating voltage of 5 kV. The thickness and properties of the layers were investigated by electron microscopy and X-ray diffraction. The fabrication processes were carried out at the concentrations of added carbon from 0 to 1 at%. The results obtained are fully consistent with the well-known solid phase reactions of carbon dissolution in Ni at 1000 °C and graphene or graphite precipitation on the surface with cooling down to the room temperatures.

Nitrogen Adsorption on Graphene Sponges Synthesized by Annealing a Mixture of Nickel and Carbon Powders

“…A similar range of values of the graphene layers was shown on the multilayer graphene obtained on transition-metal foams by the chemical vapour deposition (CVD) method [10]. The dissolution of carbon in the metal takes place using CVD process [10] and Ni -carbon powder annealing methods [1]. When a carbon atom precipitates on the metal, at the cooling stage, the formation of multilayer graphene sheets occurs.…”

“…It can be clearly seen that the GS consists of graphene sheets that are well-developed in the base plane (002), entangled and partly interconnected, with folds and wrinkles. The thickness of these sheets was determined from the XRD spectra by the width of the (002) peak [1]. The values obtained for the GS sheet thickness were in the range of 6-16 nm.…”

“…The values obtained for the GS sheet thickness were in the range of 6-16 nm. The individual graphene sheets of GS were examined using TEM [9]. The GS material was placed in isopropanol and dispersed by ultrasound and then a drop of isoprapanol with suspended graphene sheets was applied to the grid for electronic microscopy.…”

“…The samples for adsorption measurements were small pieces of GS manufactured by the authors of the research [1].…”

“…The study is dedicated to the adsorption properties of new graphenic material graphene sponge (GS) developed by the authors [1] by annealing nickel-carbon powder mixture in inert atmosphere.…”