Adsorption characteristics of vanadium on different resin-active carbon composite electrodes in capacitive deionization

The RuO 2· xH 2 O/C composites were prepared directly based on a sol-gel process under ultrasonic wave (50Hz). The specific capacitance of pure RuO 2· xH 2 O materials obtained by the method reached a value of 760F/g. Physical properties of the material and electrochemical characteristics of electrodes were described.

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Supercapacitors Based on Nickel Oxide/Carbon Materials Composites

International Journal of Electrochemistry ◽

10.4061/2011/321473 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 36

Author(s):

Katarzyna Lota ◽

Agnieszka Sierczynska ◽

Grzegorz Lota

Keyword(s):

Nickel Oxide ◽

Active Carbon ◽

Electrode Materials ◽

Carbon Materials ◽

Negative Electrode ◽

Electrochemical Capacitor ◽

Carbon Composite ◽

Electrochemical Performances ◽

Composite Electrodes ◽

Asymmetric Configuration

In the thesis, the properties of nickel oxide/active carbon composites as the electrode materials for supercapacitors are discussed. Composites with a different proportion of nickel oxide/carbon materials were prepared. A nickel oxide/carbon composite was prepared by chemically precipitating nickel hydroxide on an active carbon and heating the hydroxide at 300 ∘Cin the air. Phase compositions of the products were characterized using X-ray diffractometry (XRD). The morphology of the composites was observed by SEM. The electrochemical performances of composite electrodes used in electrochemical capacitors were studied in addition to the properties of electrode consisting of separate active carbon and nickel oxide only. The electrochemical measurements were carried out using cyclic voltammetry, galvanostatic charge/discharge, and impedance spectroscopy. The composites were tested in 6 M KOH aqueous electrolyte using two- and three-electrode Swagelok systems. The results showed that adding only a few percent of nickel oxide to active carbon provided the highest value of capacity. It is the confirmation of the fact that such an amount of nickel oxide is optimal to take advantage of both components of the composite, which additionally can be a good solution as a negative electrode in asymmetric configuration of electrode materials in an electrochemical capacitor.

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Arsenic removal from groundwater using low-cost carbon composite electrodes for capacitive deionization

Water Science & Technology ◽

10.2166/wst.2016.135 ◽

2016 ◽

Vol 73 (12) ◽

pp. 3064-3071 ◽

Cited By ~ 6

Author(s):

Ju-Young Lee ◽

Nantanee Chaimongkalayon ◽

Jinho Lim ◽

Heung Yong Ha ◽

Seung-Hyeon Moon

Keyword(s):

Arsenic Removal ◽

Vinylidene Fluoride ◽

Electrochemical Impedance ◽

Low Cost ◽

Carbon Composite ◽

Carbon Powder ◽

Capacitive Deionization ◽

Composite Electrodes ◽

Solution Ph ◽

Eis Measurements

Abstract Affordable carbon composite electrodes were developed to treat low-concentrated groundwater using capacitive deionization (CDI). A carbon slurry prepared using activated carbon powder (ACP), poly(vinylidene fluoride), and N-methyl-2-pyrrolidone was employed as a casting solution to soak in a low-cost porous substrate. The surface morphology of the carbon composite electrodes was investigated using a video microscope and scanning electron microscopy. The capacitance and electrical conductivity of the carbon composite electrodes were then examined using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. According to the CV and EIS measurements, the capacitances and electrical conductivities of the carbon composite electrodes were in the range of 8.35–63.41 F g–1 and 0.298–0.401 S cm–1, respectively, depending on ACP contents. A CDI cell was assembled with the carbon composite electrodes instead of with electrodes and current collectors. The arsenate removal test included an investigation of the optimization of several important operating parameters, such as applied voltage and solution pH, and it achieved 98.8% removal efficiency using a 1 mg L–1 arsenate solution at a voltage of 2 V and under a pH 9 condition.

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