Structural, morphological and electrical properties of graphene oxides obtained by Hummers, Tour and modified methods: a comparative study

Abstract

The aim of this paper is the comparison of structural, morphological and electrical properties of thermally extended graphite synthesized by chemical oxidation of graphite with sulfur of nitric acids at all other same conditions. Thermal treatments of graphite intercalation compounds were performed at a temperature of 600°C on the air for 10 min but additional annealing in temperature range of 100-600oC for 1 hour was done. The obtained materials were characterized by XRD, Raman spectroscopy and impedance spectroscopy. The evolution of structural ordering of thermally extended graphite samples at increasing of annealing temperature was traced. It was determined that the additional annealing allows to control the electrical conductivity and structural disordering degree of extended graphite samples that is useful for preparation of efficient current collectors for electrochemical capacitors.

Electrochemical Capacitor Based on Reduced Graphene Oxide/NiS2 Composite

“…Obtained values of capacitance are comparable to other works (Table 2). The best performance was obtained for rGO through electrochemical reduction [72] and operating in 6 M KOH (147 F g −1 at 1 A g −1 ). Comparable electrochemical performance is reported in this work.…”

“…The resultant material was washed with distilled water and HCl solution to reach a pH of about 6.5-7. AC j j CoS 2 @NiS 2 91 at 0.5 A g À 1 5 4016 [70] SC j j MXene NiS 2 102 at 1 A g À 1 32.1 749.9 [71] rGO j j rGO NiS 2 146 at 1 A g [51,[72][73][74] The percentage of NiS 2 in composite was calculated from the proportion of dried materials. We used known mass of colloidal GO, which was the source material in rGO pH 12 synthesis.…”

Electrophysical and Morphological Properties of a Hydrothermally Synthesized CuFe2O4 and CuFe2O4 / Reduced Graphene Oxide Composite

“…The resulting colloidal solution was ultrasonicated for 1 h to obtain a sparse suspension, transferred to a Teflon-lined stainless steel autoclave and kept at 150 °C for 10 h. After cooling, the obtained precipitate was collected, alternately washed with deionized water and ethanol, and then dried at 80 °C. Aqueous colloidal GO was obtained by the modified Tour method [7] and used as an additive in the synthesis of the CuFe2O4 / rGO composite material. Hydrothermal treatment of the colloidal solution of GO was carried out under the same experimental conditions as the estimated reduction process.…”

“…This work presents the results of the hydrothermal synthesis of nanostructured CuFe2O4 and CuFe2O4 / rGO composites. The main difference between this study and the previous one [6] lies in a modified synthesis protocol, which assumes the use of colloidal graphene oxide obtained by an original approach in the synthesis [7]…”

Synthesis and analysis of flakes graphene oxide

“…The physical properties of graphene-based samples have been comparatively studied [4]. In, [5] the synthesized a graphenebased sample and analyzed its structural, morphological and electrical properties and identified the possibilities of application. The recently developed pitch-based graphitic foams have a very high thermal conductivity to weight ratio.…”