Capacitive behavior of highly-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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An Improved Technique for the Exfoliation of Graphene Nanosheets and Utilization of their Nanocomposites as Fuel Cell Electrodes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.543.9 ◽

2013 ◽

Vol 543 ◽

pp. 9-12 ◽

Cited By ~ 1

Author(s):

Yuda Yürüm ◽

Burcu Saner Okan ◽

Firuze Okyay ◽

Alp Yürüm ◽

Fatma Dinç ◽

...

Keyword(s):

Sulfuric Acid ◽

Nitric Acid ◽

Graphene Nanosheets ◽

Three Dimensional ◽

Potassium Chlorate ◽

Monolayer Graphene ◽

Honeycomb Lattice ◽

Graphene Sheets ◽

Repeated Treatment ◽

Fuming Nitric Acid

Graphene is a flat monolayer of carbon atoms tightly packed into a two-dimensional 2D honeycomb lattice. The graphene sheets in graphite interact with each other through van der Waals forces to form layered structure. The first graphene sheets were obtained by extracting monolayer sheets from the three-dimensional graphite using a technique called micromechanical cleavage in 2004 [. There are numerous attempts in the literature to produce monolayer graphene sheets by the treatment of graphite. The first work was conducted by Brodie in 1859 and GO was prepared by repeated treatment of Ceylon graphite with an oxidation mixture consisting of potassium chlorate and fuming nitric acid [. Then, in 1898, Staudenmaier produced graphite oxide (GO) by the oxidation of graphite in concentrated sulfuric acid and nitric acid with potassium chlorate [. However, this method was time consuming and hazardous. Hummers and Offeman found a rapid and safer method for the preparation of GO and in this method graphite was oxidized in water free mixture of sulfuric acid, sodium nitrate and potassium permanganate [.

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ELECTROCHEMICAL PROPERTIES OF POLY SODIUM 4-STYRENESULFONATE INTERCALATED GRAPHITE OXIDE ELECTRODE IN AN AQUEOUS ELECTROLYTE

NANO ◽

10.1142/s1793292012500531 ◽

2012 ◽

Vol 07 (06) ◽

pp. 1250053 ◽

Cited By ~ 2

Author(s):

CHEOL-SOO YANG ◽

JEONG-O LEE ◽

HAE KYUNG JEONG

Keyword(s):

Electrochemical Properties ◽

Specific Capacitance ◽

Graphite Oxide ◽

Aqueous Electrolyte ◽

Cyclic Stability ◽

Oxide Electrode ◽

Galvanostatic Charge ◽

Intercalated Graphite ◽

Scan Rate ◽

Discharge Measurements

The electrochemical properties of poly sodium 4-styrenesulfonate intercalated graphite oxide (PSSGO) have been investigated in a 1 M H2SO4 electrolyte. We observed capacitor behavior at scan rate of 1–25 mV/s in a cyclic voltammetry. Specific capacitance obtained from galvanostatic charge and discharge measurements were 6 F/g to 102 F/g at 1 A/g to 0.1 A/g, respectively. The specific capacitance of PSSGO is relatively high compared to that of the precursor graphite oxide in which the specific capacitance was 11–20 F/g at 0.03 A/g. Capacitance retention was 73% after 3000 cycles, proving reliable cyclic stability up to 3000 cycles.

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Gallium Arsenide Integrated Circuits Decapsulation Technique Using Mixed Acid Chemistry For Die-Level Failure Analysis

10.31399/asm.cp.istfa2018p0496 ◽

2018 ◽

Author(s):

Harold Jeffrey M. Consigo ◽

Ricardo S. Calanog ◽

Melissa O. Caseria

Keyword(s):

Gallium Arsenide ◽

Sulfuric Acid ◽

Nitric Acid ◽

Integrated Circuits ◽

Failure Analysis ◽

Mixed Acid ◽

Optimum Parameters ◽

Plastic Package ◽

Fuming Nitric Acid ◽

Concentrated Sulfuric Acid

Abstract Gallium Arsenide (GaAs) integrated circuits have become popular these days with superior speed/power products that permit the development of systems that otherwise would have made it impossible or impractical to construct using silicon semiconductors. However, failure analysis remains to be very challenging as GaAs material is easily dissolved when it is reacted with fuming nitric acid used during standard decapsulation process. By utilizing enhanced chemical decapsulation technique with mixture of fuming nitric acid and concentrated sulfuric acid at a low temperature backed with statistical analysis, successful plastic package decapsulation happens to be reproducible mainly for die level failure analysis purposes. The paper aims to develop a chemical decapsulation process with optimum parameters needed to successfully decapsulate plastic molded GaAs integrated circuits for die level failure analysis.

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Synthesis and properties of 1,3-bis(4-nitrophenyl)-1-butene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19802120 ◽

1980 ◽

Vol 45 (7) ◽

pp. 2120-2124 ◽

Cited By ~ 1

Author(s):

Gabriel Čík ◽

Anton Blažej ◽

Kamil Antoš ◽

Igor Hrušovský

Keyword(s):

Acetic Acid ◽

Nitric Acid ◽

Double Bond ◽

Fuming Nitric Acid

1,3-Bis(4-nitrophenyl)-1-butene was prepared by nitration of 1,3-diphenyl-1-butene (I) with fuming nitric acid in acetic acid. The double bond in I was protected by addition of bromine which was eliminated after the nitration. The UV, IR and 1H- spectra of the synthesized compounds are interpreted.

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Poly(aniline-co-pyrrole)-coated Ni-doped manganese dioxide as electrode materials for supercapacitors

Functional Materials Letters ◽

10.1142/s1793604720510078 ◽

2020 ◽

Vol 13 (02) ◽

pp. 2051007

Author(s):

Jie Dong ◽

Qinghao Yang ◽

Qiuli Zhao ◽

Zhenzhong Hou ◽

Yue Zhou ◽

...

Keyword(s):

Electrochemical Performance ◽

Manganese Dioxide ◽

Specific Capacitance ◽

Electrode Materials ◽

High Specific Capacitance ◽

Cycle Stability ◽

Mass Ratio ◽

Scan Rate ◽

Poly Aniline ◽

Inorganic And Organic

Electrode materials with a high specific capacitance, outstanding reversibility and excellent cycle stability are constantly pursued for supercapacitors. In this paper, we present an approach to improve the electrochemical performance by combining the advantages of both inorganic and organic. Ni-MnO2/PANi-co-PPy composites are synthesized, with the copolymer of aniline/pyrrole being coated on the surface of Ni-doped manganese dioxide nanospheres. The inorganic–organic composite enables a substantial increase in its specific capacitance and cycle stability. When the mass ratio of Ni-MnO2 to aniline and pyrrole mixed monomer is 1:5, the composite delivers high specific capacitance of 445.49[Formula: see text]F/g at a scan rate of 2[Formula: see text]mV/s and excellent cycle stability of 61.65% retention after 5000 cycles. The results indicate that the Ni-MnO2/PANi-co-PPy composites are promising electrode materials for future supercapacitors application.

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Nanocarbon from Rocket Fuel Waste: The Case of Furfuryl Alcohol-Fuming Nitric Acid Hypergolic Pair

Nanomaterials ◽

10.3390/nano11010001 ◽

2020 ◽

Vol 11 (1) ◽

pp. 1

Author(s):

Nikolaos Chalmpes ◽

Athanasios B. Bourlinos ◽

Smita Talande ◽

Aristides Bakandritsos ◽

Dimitrios Moschovas ◽

...

Keyword(s):

Nitric Acid ◽

Furfuryl Alcohol ◽

Materials Science ◽

Ambient Conditions ◽

Materials Synthesis ◽

Rocket Fuel ◽

Carbon Nanosheets ◽

New Synthesis ◽

Fuming Nitric Acid ◽

Liquid Rocket

In hypergolics two substances ignite spontaneously upon contact without external aid. Although the concept mostly applies to rocket fuels and propellants, it is only recently that hypergolics has been recognized from our group as a radically new methodology towards carbon materials synthesis. Comparatively to other preparative methods, hypergolics allows the rapid and spontaneous formation of carbon at ambient conditions in an exothermic manner (e.g., the method releases both carbon and energy at room temperature and atmospheric pressure). In an effort to further build upon the idea of hypergolic synthesis, herein we exploit a classic liquid rocket bipropellant composed of furfuryl alcohol and fuming nitric acid to prepare carbon nanosheets by simply mixing the two reagents at ambient conditions. Furfuryl alcohol served as the carbon source while fuming nitric acid as a strong oxidizer. On ignition the temperature is raised high enough to induce carbonization in a sort of in-situ pyrolytic process. Simultaneously, the released energy was directly converted into useful work, such as heating a liquid to boiling or placing Crookes radiometer into motion. Apart from its value as a new synthesis approach in materials science, carbon from rocket fuel additionally provides a practical way in processing rocket fuel waste or disposed rocket fuels.

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