Co9S8/graphene nanocomposites (Co9S8/G) at various concentrations of graphene and Co9S8 were prepared and tested for its electrochemical behaviour for supercapacitors.

Velmurugan V

Centre for Nanotechnology Research

Vellore Campus

Nirmala Grace A

Ramachandran R

Saranya M

Santhosh C

Raghupathy B.P.C

Jeong S.K

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

RSC Adv.

A series of vanadium pentoxide (V2O5/G) nanocomposites with graphene and doped graphene was synthesized by a facile solvothermal route and the supercapacitor performance of the obtained materials were further examined. The various heteroatom doped graphene composites viz. B doped (V2O5/BG), N doped (V2O5/NG) and BN codoped graphene (V2O5/BNG) was analyzed systematically to understand the effect of the dopants and their electrochemical properties. The structural and morphology of the obtained nanocomposites were investigated by using X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Thermogravimetric Analysis (TGA), Transmission Electron Microscope (TEM) and Brunauer, Emmett and Teller (BET). The results showed that the prepared V2O5 nanoparticles are deposited uniformly on graphene sheets. The electrochemical behavior of the nanocomposites were further analyzed to understand its supercapacitance properties in KOH electrolyte. A maximum specific capacitance of 1032.6 F/g was observed for V2O5/NG at 1 mVs-1 scan rate. Galvanostatic charge/discharge curves showed an excellent cyclic stability with higher charge/discharge duration with an energy density of 185.86 Wh/Kg and a power density of 37.20 W/Kg respectively for V2O5/NG nanocomposite. The graphene moieties provide fast and smooth electron transfer between V2O5 materials, thus leading to higher electrode performance compared with V2O5. The doping of heteroatom on graphene has been proven to be an effective way to tailor the properties of graphene and render its potential use for supercapacitor electrodes. © 2018 Elsevier Ltd

Electrochimica Acta

Heteroatom doped graphene based hybrid electrode materials for supercapacitor applications

A series of SnS/Graphene (SnS/G) nanocomposites at various concentrations of graphene were synthesized by a wet chemical route and the prepared composites were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), High Resolution Transmission Electron Microscopy (HRTEM) for its structural and morphological investigation. Results show that the prepared SnS nanoparticles in the composite are [Formula: see text]30[Formula: see text]nm sized and uniformly dispersed on graphene sheets. To test the supercapacitance behavior, electrochemical measurements were carried out in 6[Formula: see text]M KOH electrolyte. A maximum specific capacitance of 984[Formula: see text]F/g was observed for SnS/G-c at 5[Formula: see text]mVs[Formula: see text] scan rate. Galvanostatic charge/discharge curves showed an excellent cyclic stability with higher charge/discharge duration, and hence could be used for high performance supercapacitor applications.

International Journal of Nanoscience

Wet Chemical Synthesis of SnS/Graphene Nanocomposites for High Performance Supercapacitor Electrodes

Nanocomposites of MnS anchored on graphene, nitrogen-doped graphene and boron-doped graphene have been prepared by a simple wet chemical process.

Fulltext

RSC Advances

MnS nanocomposites based on doped graphene: simple synthesis by a wet chemical route and improved electrochemical properties as an electrode material for supercapacitors

Tin oxide/graphene (SnO2/G) nanocomposites were prepared by a simple wet chemical route and the as prepared nanocomposites were characterized by X-ray diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and Fourier transform infrared spectra (FTIR). The characterized results showed the tetragonal structure of SnO2 nanostructures on uniform distribution on graphene sheets with a particle size of ∼50 nm. The reduction of graphene oxide to graphene during SnO2/G synthesis was confirmed from FTIR analysis. HRTEM analysis showed that the individual SnO2 nanoparticles deposited on graphene sheets. The electrochemical performances of SnO2/G nanocomposites towards supercapacitors were studied in 6M KOH electrolyte. A maximum specific capacitance of 818.6 F/g was obtained for SnO2/G-a composite at 5 mV/s scan rate suggesting that the presence of graphene matrix in SnO2 nanoparticles have enhanced the electrochemical behaviour of SnO2. The galvanostatic charge/discharge studies confirmed the good cyclic stability of the composite electrode. These excellent electrochemical properties suggested that the SnO2/G nanocomposites could be used for high energy density supercapacitor electrode materials. © 2016

Materials Research Bulletin

Synthesis of tin oxide/graphene (SnO 2 /G) nanocomposite and its electrochemical properties for supercapacitor applications

Zinc sulfide decorated graphene nanocomposites are synthesized by a facile solvothermal approach and the prepared composites are analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), High Resolution Transmission electron microscopy (HRTEM), Fourier transform infrared (FTIR), Ultraviolet visible spectroscopy (UV), Photoluminescence spectroscopy (PL) and Raman spectrum. Results show the effective reduction of graphene oxide (GO) to graphene and decoration of ZnS nanoparticles on graphene sheets. Towards supercapacitor applications, the electrochemical measurements of different electrodes are performed in 6 M KOH electrolyte. A series of composites with different loadings of graphene is synthesized and tested for its electrochemical properties. The specific capacitance of the electrodes are evaluated from cyclic voltammetry (CV) studies and a maximum specific capacitance of 197.1 F/g is achieved in ZnS/G-60 electrode (60 indicates the weight ratio of GO) at scan rate of 5 mV s-1. A capacitance retention of about 94.1% is observed even after 1000 cycles for ZnS/G-60 electrode, suggesting the long time cyclic stability of the composite electrode. Galvanostatic charge-discharge curves show the highly reversible process of ZnS/G-60 electrode. Electrochemical Impedance Spectrum (EIS) shows a high conductivity of composite electrode suggesting that the composites are good candidates for energy storage. © 2015 Elsevier Ltd.

Solvothermal synthesis of Zinc sulfide decorated Graphene (ZnS/G) nanocomposites for novel Supercapacitor electrodes

Nanocomposites of Co3S4 grown on nitrogen-doped graphene (NG) (Co3S4-NG) have been prepared at various concentrations of NG. The supercapacitive behaviors of the developed nanocomposites were assessed with cyclic voltammetry and galvanostatic charge discharge techniques. The nanocomposites exhibit excellent capacitive behavior with a high specific capacitance of 2427F/g at 2mV/s in Co3S4-NG-7 composite (7 indicates the percentage weight ratio of NG). The superior electrochemical performances could be due to synergistic effects between Co3S4 and NG, high charge mobility and good flexibility of graphene structures. These results indicate that the developed hybrid materials are promising candidates for high performance energy applications. © 2014 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.

Electroanalysis

Facile Synthesis and Electrochemical Properties of Co3S4-Nitrogen-Doped Graphene Nanocomposites for Supercapacitor Applications

Graphene platelets were synthesized from graphene oxide by chemical and electrochemical route. Under the chemical method, sodium borohydride and hydrazine chloride were used as reductants to produce graphene. In this paper, a novel and cost effective electrochemical method, which can simplify the process of reduction on a larger scale, is demonstrated. The electrochemical method proposed in this paper produces graphene in powder form with good yield. The atomic force microscopic images confirmed that the graphene samples prepared by all the routes have multilayers of graphene. The electrochemical process provided a new route to make relatively larger area graphene sheets, which will have interest for further patterning applications. Attempt was made to quantify the quantum of reduction using cyclic voltammetry and choronopotentiometry techniques on reduced graphene samples. As a measure in reading the specific capacitance values, a maximum specific capacitance value of 265.3 F/g was obtained in sodium borohydride reduced graphene oxide. © 2013 Elsevier Ltd. All rights reserved.

Journal	Data powered by TypesetRSC Adv.
Publisher	Data powered by TypesetRoyal Society of Chemistry (RSC)
ISSN	20462069
Open Access	0