SYNTHESIS OF PARTIALLY OXIDIZED GRAPHITE OXIDE BY OXIDATION OF NANOGRAPHITE

The influence of light radiation with different wavelengths (546, 380, 365 nm) on the coatings of oxidized graphite and its intercalated compound with ammonium dodecahydrododecaborate (NH4)2B12H12 was studied. The transmission and absorption spectra of the coatings were measured before and after irradiation. It was shown that the optical density of the coatings increased because of carbon release (blackening), which was especially strong during UV irradiation. Under the same conditions (wavelength, power, time), the change in the optical density was much larger for the intercalated compound than for oxidized graphite. This can be explained by the presence of the anion B12H12 2- in the former. It is not appropriate to refer to graphite oxide or reduced graphite oxide simply as graphene since their properties are substantially different.

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Removal of Lead by Oxidized Graphite

C – Journal of Carbon Research ◽

10.3390/c7010023 ◽

2021 ◽

Vol 7 (1) ◽

pp. 23

Author(s):

Namasivayam Selvanantharajah ◽

Poobalasuntharam Iyngaran ◽

Poobalasingam Abiman ◽

Navaratnarajah Kuganathan

Keyword(s):

Graphite Oxide ◽

Photoelectron Spectroscopy ◽

Graphite Powder ◽

Effective Concentration ◽

Lead Ion ◽

Ion Adsorption ◽

Xps Analysis ◽

X Ray ◽

Oxidized Graphite ◽

Final Composite

Lead ion adsorption on the surfaces of pristine and oxidized graphite is studied quantitatively using X-ray photoelectron spectroscopy (XPS) and standard electrochemical measurements. The XPS analysis confirmed the oxidation of graphite, yielding a final composite consisting of 15.97% of oxygen and 84.03% of carbon in comparison with the pristine graphite powder consisting of 6.13% oxygen and 93.87% carbon. The adsorption of lead (II) ion was confirmed by the peaks observed at 138 eV and 143.8 eV, associated with the emissions from Pb4f 7/2 and Pb4f 5/2, respectively. The effective concentration of Pb2+ ion and the optimum dosage of oxidized graphite were calculated to be 400 µM and 200 mg, respectively. Adsorption capacity of bare graphite was 41.18%, whereas that of oxidized graphite was 73.3%. The present results show that graphite oxide is a candidate material for the adsorption of Pb2+ ion from water.

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Insight into the role of the oxidized graphite precursor on the properties of copper-based MOF/graphite oxide composites

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2013.06.002 ◽

2013 ◽

Vol 179 ◽

pp. 205-211 ◽

Cited By ~ 18

Author(s):

Svetlana Bashkova ◽

Teresa J. Bandosz

Keyword(s):

Graphite Oxide ◽

Oxidized Graphite ◽

Oxide Composites ◽

Insight Into

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Capacitive behavior of highly-oxidized graphite

Materials Science-Poland ◽

10.2478/s13536-013-0200-y ◽

2014 ◽

Vol 32 (3) ◽

pp. 307-314 ◽

Cited By ~ 1

Author(s):

Mateusz Ciszewski ◽

Andrzej Mianowski

Keyword(s):

Nitric Acid ◽

Specific Capacitance ◽

Oxygen Content ◽

Graphite Oxide ◽

Potassium Chlorate ◽

Electrochemical Measurements ◽

Capacitive Behavior ◽

Scan Rate ◽

Fuming Nitric Acid ◽

Oxidized Graphite

AbstractCapacitive behavior of a highly-oxidized graphite is presented in this paper. The graphite oxide was synthesized using an oxidizing mixture of potassium chlorate and concentrated fuming nitric acid. As-oxidized graphite was quantitatively and qualitatively analyzed with respect to the oxygen content and the species of oxygen-containing groups. Electrochemical measurements were performed in a two-electrode symmetric cell using KOH electrolyte.It was shown that prolonged oxidation causes an increase in the oxygen content while the interlayer distance remains constant. Specific capacitance increased with oxygen content in the electrode as a result of pseudo-capacitive effects, from 0.47 to 0.54 F/g for a scan rate of 20 mV/s and 0.67 to 1.15 F/g for a scan rate of 5 mV/s. Better cyclability was observed for the electrode with a higher oxygen amount.

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Synthesis, Composition, and Properties of Partially Oxidized Graphite Oxides

Materials ◽

10.3390/ma12152367 ◽

2019 ◽

Vol 12 (15) ◽

pp. 2367 ◽

Cited By ~ 2

Author(s):

Michal Lojka ◽

Boris Lochman ◽

Ondřej Jankovský ◽

Adéla Jiříčková ◽

Zdeněk Sofer ◽

...

Keyword(s):

Thermal Stability ◽

Raman Spectroscopy ◽

Cyclic Voltammetry ◽

Graphite Oxide ◽

Argon Atmosphere ◽

Oxidizing Agent ◽

Oxidized Graphite ◽

Simple Technology ◽

Synthesis Composition ◽

Graphite Oxides

The aim of this paper is to prepare and characterize partially-oxidized graphite oxide and consider if it is possible to affect the level of oxidation of particles by an adjustment of the oxidizing agent. Several samples were prepared, using different amounts of oxidizing agent. The samples were subsequently analyzed. The C/O ratio was evaluated from XPS, EDS, and EA. The amount and type of individual oxygen functionalities were characterized by XPS, Raman spectroscopy, and cyclic voltammetry. The structure was studied by SEM and XRD. Thermal stability was investigated by STA-MS in argon atmosphere. The results can be useful in order to design simple technology for graphite oxide synthesis with required oxygen content.

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Preparation and Property of Reduced Graphene for Hummers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.591.301 ◽

2013 ◽

Vol 591 ◽

pp. 301-304

Author(s):

Yan Li Jiang ◽

Mei Tian ◽

Ying Hui Yu ◽

Jia Yao Liu ◽

Shuang Liu

Keyword(s):

Hydrazine Hydrate ◽

Graphite Oxide ◽

Oxidation Reaction ◽

Lattice Structure ◽

Silver Ions ◽

Graphene Layers ◽

Hummers Method ◽

Reduced Graphene ◽

Oxidized Graphite ◽

Graphene Material

Graphene material has ideal lattice structure and unique electrical, optical and other properties. In the electronics, composite materials, and other fields it has a broad application prospect. In this paper, using the Hummers method, to prepare oxidized graphite and graphene , to optimize the conditions of the preparation of graphite oxide. With two kinds of reductors, glucose and hydrazine hydrate, reduction graphite oxide, and dropped silver ions in the process of reduction. Using XRD, SEM and Raman spectra to character and analyze the products. The result showed that the graphite and silver ions in the oxidation reaction process were both restored by glucose, hydrazine hydrate. This structure that silver nanoparticles are uniformly distributed in the graphene sheet layers, can effectively prevent the reunion of graphene layers, and also upset the rules of the pile of the graphene layers.

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