• Journal of Korean Society of Environmental Engineers
• /
• v.35 no.11
• /
• pp.815-820
• /
• 2013

The purpose of this research is to prepare the aluminum electrode coated with activated carbon for removing air pollution dust. The experiments were studied on the selection of optimal polymer for binding aluminum plate with powdered activated carbon, preventing the pore blocking of activated carbon from polymer binder, and the dust treatability for the prepared activated carbon electrode. The optimal adhesive for coating activated carbon on an electric aluminum plate was polyvinyl acetate (PVA) with vinyl functional group. For the opening of the blocked pore with polymer, it was very effective to embed polymer solvent in pore of activated catbon firstly before mixing activated carbon with PVA, and then to devolatilize the embedded solvent of carbon pore at high temperature. The mass of trapped dust on aluminum electrode coated with activated carbon was about double of the trapped one on just aluminum electrode.

• Applied Chemistry for Engineering
• /
• v.25 no.2
• /
• pp.193-197
• /
• 2014

The electrode for gas sensor was prepared by using pitch-based activated carbon fibers and polyvinyl alcohol (PVA) to investigate the toxic gas sensing characteristics. The physicochemical properties of activated carbon fibers electrode for gas sensor were analyzed with SEM and BET. Toxic gases sensing property of the electrode was also identified by different toxic gases such as $NH_3$, NO and $CO_2$. The specific surface area of activated carbon fibers electrode for gas sensor was decreased by 33% owing to PVA used as a binder compared with the activated carbon fibers. However, its pore size distribution of the ACF electrode was not greatly influenced by PVA. The activated carbon fibers electrode for gas sensor responded to toxic gases by electron hopping unlike semiconductor based gas sensors. In this study, activated carbon fibers electrode was decreased to 7.5% in resistance for the NH3 gas of the 100 ppm concentration and its $NH_3$ gas sensing property was confirmed the most excellent compared with other toxic gases.

• Carbon letters
• /
• v.9 no.2
• /
• pp.137-144
• /
• 2008

The commercial activated carbons are typically prepared by activation from coconut shell char or coal char containing lots of inorganic impurities. They also have pore structure and pore size distribution depending on nanostructure of precursor materials. In this study, two types of commercial activated carbons were applied for EDLC electrode by removing impurities with acid treatments, and controlling pore size distribution and contents of functional group with heat treatment. The effect of the surface functional groups on electrochemical performance of the activated carbon electrodes was investigated. The initial gravimetric and volumetric capacitance of coconut based activated carbon electrode which was acid treated by $HNO_3$ and then heat treated at $800^{\circ}C$ were 90 F/g and 42 F/cc respectively showing 94% of charge-discharge efficiency. Such a good electrochemical performance can be possibly applied to the medium capacitance of EDLC.

• Applied Chemistry for Engineering
• /
• v.21 no.3
• /
• pp.265-271
• /
• 2010

Desalination effects of capacitive deionization (CDI) process was studied using $TiO_2$/activated carbon electrode. In order to enhance the wettability of electrode and decrease a electrode resistance, $TiO_2$ was coated on activated carbon. By means of $TiO_2$ coating on activated carbon, electric double layer to adsorption content in CDI process was increased. It was identified from TEM, XRD, and XPS that the activated carbon based on $TiO_2$ composite was fabricated successfully by means of sol-gel method. As a results of cyclic voltammetry and impedance, it was identified that $TiO_2$/activated carbon electrode has more electric double later capacitance and less diffusion resistance than activated carbon. Also charge-discharge and ion conductivity profiles showed that the ion removal ratios of $TiO_2$/activated carbon electrode in NaCl electrolyte of $1000\;{\mu}S/cm$ more increased about 39% than that of activated carbon. In conclusion it was possible to identify that the carbon electrode coated $TiO_2$ as electrode material was more effective than raw carbon electrode.

• Composites Research
• /
• v.35 no.1
• /
• pp.1-7
• /
• 2022

The activated carbon is a very good choice for using as supercapacitor electrode materials. Herein, the flower of Shorea robusta, a bio-waste material was successfully used to synthesize the activated carbons for application as supercapacitor electrode materials. The activated carbon was synthesized through chemical activation process followed by thermal treatment at 700℃ in presence of N₂ atmosphere using KOH, ZnCl₂ and H₃PO₄ as the activating agents. The physicochemical analyses demonstrate that the obtained activated carbons are graphitic in nature and the degree of disorder of the graphitic carbons is changed with the activating agents. The activated carbon obtained from Shorea robusta flower (ACSF-K) electrode shows the specific capacitance of ~610 F g^-1 at 2 A g^-1 current density, which is higher than ACSF-Z (560 F g^-1) and ACSF-H (470 F g^-1) electrode material under the identical current density. The synthesized graphitic carbons also demonstrated good rate capability and high electrochemical stability as supercapacitor electrode.

• Korean Journal of Materials Research
• /
• v.24 no.6
• /
• pp.285-292
• /
• 2014

Commercial activated-carbon used as the electrode material of an electric double-layer capacitor (EDLC) was posttreated with various acids and alkalis to increase its capacitance. The carbon samples prepared were then heat-treated in order to control the amount of acidic functional groups formed by the acid treatments. Coin-type EDLC cells with two symmetric carbon electrodes were assembled using the prepared carbon materials and an organic electrolyte. The electrochemical performance of the EDLC was measured by galvanostatic charge-discharge, cyclic voltammetry, and electrochemical impedance spectroscopy. Among the various activated carbons, the carbon electrodes (CSsb800) prepared by the treatments of coconutshell-based carbon activated with NaOH and $H_3BO_5$, and then heat treated at $800^{\circ}C$ under a flow of nitrogen gas, showed relatively good electrochemical performance. Although the specific-surface-area of the carbon-electrode material ($1,096m^2/g$) was less than that of pristine activated-carbon ($1,122m^2/g$), the meso-pore volume increased after the combined chemical and heat treatments. The specific capacitance of the EDLC increased from 59.6 to 74.8 F/g (26%) after those post treatments. The equivalent series resistance of EDLC using CSsb800 as electrode was much lower than that of EDLC using pristine activated carbon. Therefore, CSsb800 exhibited superior electrochemical performance at high scan rates due to its low internal resistance.

• Journal of the Korean Electrochemical Society
• /
• v.12 no.3
• /
• pp.287-294
• /
• 2009

Desalination effects of Capacitive deionization(CDI) process using activated carbon $TiO_2$ composite electrode. In this study, we made the activated carbon electrod and activated carbon $TiO_2$ composite electrode, which analysed at cyclic voltammetry and charge-discharge. The results measured for discharge capacitance in cyclic voltammetry were 125 F/g in activated carbon electrode and capacitance of activatd carbon composite electrode was increased about two time, 243 F/g. The $TiO_2$ content of activated carbon composite electrode was 10 wt.%. When it was added wtih TiO2, electric double layer adsorption content was increased, so it was increased 25% in ion removal ratio of activated carbon electrode.

• ETRI Journal
• /
• v.38 no.2
• /
• pp.252-259
• /
• 2016

Di(1-aminopyrene)quinone (DAQ) as a quinone-containing conducting additive is synthesized from a solution reaction of 1-aminopyrene and hydroquinone. To utilize the conductive property of DAQ and its compatibility with activated carbon, a composite electrode for a supercapacitor is also prepared by blending activated carbon and DAQ (3:1 w/w), and its supercapacitive properties are characterized based on the cyclic voltammetry and galvanostatic charge/discharge. As a result, the composite electrode adopting DAQ exhibits superior electrochemical properties, such as a higher specific capacitance of up to $160F{\cdot}g^{-1}$ at $100mV{\cdot}s^{-1}$, an excellent high-rate capability of up to $1,000mV{\cdot}s^{-1}$, and a higher cycling stability with a capacitance retention ratio of 82% for the 1,000th cycle.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.11a
• /
• pp.336-337
• /
• 2005

This study shows the effect of addition of $LiCoO_2$, with different milling time ranging from 0, 30, 200 hours, to the activated carbon electrode. Test cells consisting of activated carbon (100-X%) and $LiCoO_2$ (X%)were made (where X=10, 20, and 40). Test cells with varying concentrations of $LiCoO_2$ which differ in the milling time showed improved specific capacity compare with the cells fabricated using activated carbon alone. The enhanced capacity may be caused due to the addition of $LiCoO_2$ powders at varying concentration. An improved ESR value obtained may be caused by the smaller particle size of $LiCoO_2$. It was concluded that finer the particle size higher will be the efficiency.

• Applied Chemistry for Engineering
• /
• v.21 no.1
• /
• pp.11-17
• /
• 2010

Modifying surface of activated carbon for the electrode of EDLC with an organic electrolyte was investigated to improve the electrochemical performance of EDLC by the microwave radiation. Three kinds of activated carbons, prepared activated carbon from petroleum cokes and pitch cokes and commercial activated carbon BP-25, were used for this study. For all investigated activated carbons, hydrophilic functional groups-containing oxygen disappeared from the surface of activated carbon as microwave radiation. And as microwave radiation time was increased, the specific surface area and total pore volume of activated carbons were reduced and average pore diameter were increased. From theses effects, interfacial resistance of EDLC with the modified activated carbon electrode was drastically decreased, and discharge capacitance was increased although the specific surface area of activated carbon was reduced by this microwave radiation.