Cobalt Oxide-Decorated Silicon Carbide Nano-Tree Array Electrode for Micro-Supercapacitor Application

A cobalt oxide (Co3O4)-decorated silicon carbide (SiC) nano-tree array (denoted as Co3O4/SiC NTA) electrode is synthesized, and it is investigated for the use in the micro-supercapacitor. Firstly, the well-standing SiC nanowires (NWs) are prepared by nickel (Ni)-catalyzed chemical vapor deposition (CVD) method, and then the thin layer of Co3O4 and the hierarchical Co3O4 nano-flower-clusters are, respectively fabricated on the side-walls and the top side of the SiC NWs via electrodeposition. The deposition of Co3O4 on the SiC NWs benefits for the charge transfer at the electrode/aqueous electrolyte interface due to its extremely hydrophilic surface characteristic after Co3O4 decoration. Furthermore, the Co3O4/SiC NTA electrode would possess a directional charge transport route along the nanowire length of SiC NWs owing to their well-standing architecture. By using the Co3O4/SiC NTA electrode for micro-supercapacitor, the areal capacitance obtained from cyclic voltammetry measurement reaches 845 mF cm−2 at a 10 mV s−1 scan rate. Finally, the capacitance durability is also evaluated by the cycling test of cyclic voltammetry at a high scan rate of 150 mV s−1 for 2000 cycles.

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Metal coatings on SiC nanowires by plasma-enhanced chemical vapor deposition

Journal of Materials Research ◽

10.1557/jmr.2005.0074 ◽

2005 ◽

Vol 20 (3) ◽

pp. 549-553 ◽

Cited By ~ 11

Author(s):

Aaron D. LaLonde ◽

M. Grant Norton ◽

David N. McIlroy ◽

Daqing Zhang ◽

Radhakrishnan Padmanabhan ◽

...

Keyword(s):

Silicon Carbide ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Pt Nanoparticles ◽

Average Particle ◽

Size Distributions ◽

Metal Coatings ◽

Sic Nanowires ◽

High Particle

Coating of nanowires is being investigated to broaden potential uses for future applications. Coatings of Ni and Pt nanoparticles have been synthesized on silicon carbide nanowires by plasma enhanced chemical vapor deposition. Coatings with high particle densities with average particle diameters of 2.76 and 3.28 nm for Pt and Ni, respectively, were formed with narrow size distributions. Plasma enhanced chemical vapor deposition appears to be an efficient method for production of metal coatings on nanowires.

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Preparation and Performance of Co3O4/Polyaniline Nano-Composite for Supercapacitor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.2042 ◽

2011 ◽

Vol 239-242 ◽

pp. 2042-2045 ◽

Cited By ~ 4

Author(s):

Shu Ping Yu ◽

Xiao Cong Chang ◽

Zhong Ming Wang ◽

Ke Fei Han ◽

Hong Zhu

Keyword(s):

Cyclic Voltammetry ◽

Emulsion Polymerization ◽

Cobalt Oxide ◽

Electrochemical Behavior ◽

Electrochemical Impedance ◽

X Ray Diffraction ◽

Nano Composite ◽

X Ray ◽

Scan Rate ◽

And Performance

Cobalt oxide-Polyaniline (Co3O4/PANI) nanocomposites were prepared via inverted emulsion polymerization. The structure of the obtained composites were characterized by X-ray diffraction (XRD). The electrochemical behavior was studied by cyclic voltammetry(CV) and electrochemical impedance spectrometry(EIS) experiments. The Co3O4/PANI(1:2) composite calcined at 400°C exhibits the highest capacitance value of 357 F/g at the scan rate of 5mV/s.

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TEM of grain growth and phase transformations during creep of SCS-6 silicon carbide fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138129 ◽

1995 ◽

Vol 53 ◽

pp. 350-351

Author(s):

L. A. Giannuzzi ◽

C. A. Lewinsohn ◽

C. E. Bakis ◽

R. E. Tressler

Keyword(s):

Silicon Carbide ◽

Creep Rate ◽

Vapor Deposition ◽

Chemical Vapor ◽

Primary Creep ◽

Excess Carbon ◽

Silicon Carbide Fibers ◽

Sic Fiber ◽

Carbon Core ◽

Grain Width

The SCS-6 SiC fiber is a 142 μm diameter fiber consisting of four distinct regions of βSiC. These SiC regions vary in excess carbon content ranging from 10 a/o down to 5 a/o in the SiC1 through SiC3 region. The SiC4 region is stoichiometric. The SiC sub-grains in all regions grow radially outward from the carbon core of the fiber during the chemical vapor deposition processing of these fibers. In general, the sub-grain width changes from 50nm to 250nm while maintaining an aspect ratio of ~10:1 from the SiC1 through the SiC4 regions. In addition, the SiC shows a <110> texture, i.e., the {111} planes lie ±15° along the fiber axes. Previous has shown that the SCS-6 fiber (as well as the SCS-9 and the developmental SCS-50 μm fiber) undergoes primary creep (i.e., the creep rate constantly decreases as a function of time) throughout the lifetime of the creep test.

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On the theory of cyclic voltammetry for multiple nucleation and growth: Scan rate influence

Journal of Electroanalytical Chemistry ◽

10.1016/j.jelechem.2021.115056 ◽

2021 ◽

Vol 883 ◽

pp. 115056

Author(s):

Alexander V. Kosov ◽

Olga V. Grishenkova ◽

Olga L. Semerikova ◽

Vladimir A. Isaev ◽

Yurii P. Zaikov

Keyword(s):

Cyclic Voltammetry ◽

Nucleation And Growth ◽

Scan Rate

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Comparative analysis of electrodeposited cobalt oxide thin films by chronoamperometry and chronopotentiometry modes for supercapacitor application.

10.1063/5.0017211 ◽

2020 ◽

Author(s):

S. S. Gavande ◽

A. S. Salunkhe ◽

Y. H. Navale ◽

Shivani Gavande ◽

P. S. Kulkarni ◽

...

Keyword(s):

Thin Films ◽

Comparative Analysis ◽

Cobalt Oxide ◽

Oxide Thin Films ◽

Supercapacitor Application

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Surfactant-free synthesis of carbon-supported silver (Ag/C) nanobars as an efficient electrocatalyst for alcohol tolerance and oxidation of sodium borohydride in alkaline medium

SN Applied Sciences ◽

10.1007/s42452-021-04601-9 ◽

2021 ◽

Vol 3 (6) ◽

Author(s):

Santanu Dey ◽

Pradipta Chakraborty ◽

Dhiraj Kumar Rana ◽

Subhamay Pramanik ◽

Soumen Basu

Keyword(s):

Cyclic Voltammetry ◽

Ethylene Glycol ◽

Alkaline Medium ◽

Sodium Borohydride ◽

Metallic Silver ◽

Alcohol Tolerance ◽

Current Ratio ◽

X Ray ◽

Scan Rate ◽

Borohydride Oxidation

AbstractWe have synthesized carbon-supported silver (Ag/C) nanobars by a simple surfactant-free hydrothermal method using glucose as the reducing reagent as well as the source of carbon in Ag/C nanobars. Physicochemical characterization of the materials was performed by X-ray Diffraction (XRD), field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The XRD pattern confirmed the presence of a pure metallic silver phase. No carbon phase was detected, which indicates that the carbon exists mainly in the amorphous form. The electrocatalytic activity of Ag/C in different electrolyte solutions such as 0.5 M NaOH, 0.5 M NaOH + 1 M ethanol (EtOH), 0.5 M NaOH + 1 M ethylene glycol (EG), and 0.5 M NaOH + 0.01 M NaBH4 (sodium borohydride) was studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA) study. Alcohol tolerance of the catalysts was also established in the presence of ethanol and ethylene glycol. The forward-to-backward current ratio from cyclic voltammetry (CV) study of Ag/C-20 (20 h) in 0.5 M NaOH + 1 M ethanol solution at 100 mV s−1 scan rate is 4.13 times higher compared to that of Ag/C-5 (5 h). Hence, Ag/C-20 is a better candidate for the tolerance of ethanol. In the presence of ethylene glycol (1 M) in 0.5 M NaOH solution, it is obtained that the forward-to-backward current ratio at the same scan rate for Ag/C-20 is lower than that in the presence of ethanol. The durability of the catalyst was studied by chronoamperometry measurement. We studied the electrochemical kinetics of Ag/C catalysts for borohydride oxidation in an alkaline medium. The basic electrochemical results for borohydride oxidation show that Ag/C has very well strength and activity for direct borohydride oxidation in an alkaline medium. The reaction of borohydride oxidation with the contemporaneous BH4−. hydrolysis was noticed at the oxidized silver surface. Among all the synthesized Ag/C catalysts, Ag/C-20 exhibited the best electrocatalytic performance for borohydride oxidation in an alkaline medium. The activation energy and the number of exchange electrons at Ag/C-20 electrode surface for borohydride electro-oxidation were estimated as 57.2 kJ mol−1 and 2.27, respectively.

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