• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.322-328
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• 2013

Copper iodide was employed as a modifier for preparation of a new carbon ceramic electrode. For the first time, the catalytic oxidation of amoxicillin (AMX) was demonstrated by cyclic voltammetry, chronoamperometry and amperometry methods at the surface of this modified carbon ceramic electrode. The copper iodide modified sol-gel derived carbon ceramic (CIM-SGD-CC) electrode has very high catalytic ability for electrooxidation of amoxicillin. The catalytic oxidation peak current was linearly dependent on the amoxicillin concentration and the linearity range obtained was 100 to 1000 ${\mu}mol\;L^{-1}$ with a detection limit of 0.53 ${\mu}mol\;L^{-1}$. The diffusion coefficient ($D=(1.67{\pm}0.102){\times}10^{-3}\;cm^2\;s^{-1}$), and the kinetic parameter such as the electron transfer coefficient (${\alpha}$) and exchange current density ($j_0$) for the modified electrode were calculated. The advantages of the modified CCE are its good stability and reproducibility of surface renewal by simple polishing, excellent catalytic activity and simplicity of preparation.

• Journal of the Semiconductor & Display Technology
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• v.2 no.4
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• pp.27-30
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• 2003

The effect of fabrication method of catalytic layer on electrode performance has been investigated. Brush, spray gun and screen printer were used as fabrication tool and catalytic layers were formed by several methods in screen printing. Direct screen printing on polymer membrane, screen printing on carbon paper, and their combined method were applied. In the electrode fabricated by the screen printing method, Pt loading of Pt/C catalysts could be cut down to 50%, compared with results by the brushing and spraying methods. The best result of electrode was obtained as 0.6 V, at 1 A/$\textrm{cm}^2$ when catalytic layer was formed by the combined way.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1192-1196
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• 2001

A diaphorase enzyme electrode for the catalytic reduction of NAD+ , the oxidized form of nicotinamide adenine dinucleotide, has been prepared. The enzyme layer grew spontaneously over an aminoethanethiol self assembled monolayer on a go ld plate electrode. The growth was accomplished by simply dipping the electrode covered by the aminoethanethiol monolayer into a solution containing both glutaraldehyde and diaphorase. We suggested that the glutaraldehyde as a cross-linking reagent was attached to the amino groups of the aminoethanethiol monolayer and the diaphorase enzyme molecules were bound to free aldehyde groups of the glutaraldehyde. Further attachments of the enzyme molecules over the bound enzyme molecules continued with the bridging of the glutaraldehyde. In frequency measurements with a quartz crystal microbalance, the frequency decrease was much more than it was for that of the enzyme monolayer formation, and an enzyme layer thicker than a monolayer was formed. The modified electrode was employed to reduce NAD+ , using diffusional methyl viologen as an electron transfer mediator. The NAD+ was electrocatalytically reduced, and the catalytic current was almost equivalent to that with the multilayered electrode of ten enzyme layers.

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.754-760
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• 1998

It was found that the adsorption of a cobalt(III) complex with a macrocyclic ligand, C-meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (hmc), was induced on a glassy carbon electrode by heavily oxidizing the electrode surface. Adsorption properties are discussed. The glassy carbon electrode with the adsorbed complex was employed to see the catalytic activities for the electro-reduction of O2. In the presence of oxygen, reduction of (hmc)Co3+ showed two cathodic waves in cyclic voltammetry. Compared to the edge plane graphite electrode at which two cathodic waves were also observed in a previous study, catalytic reduction of O2 occurred in the potential region of the first wave while it happened in the second wave region with the other electrode. A rotating disk electrode after the same treatment was employed to study the mechanism of the O2 reduction and two-electron reduction of O2 was observed. The difference from the previous results was explained by the different reactivity of the (hmc)CoOOH2+ intermediate, which is produced after the two electron reduction of (hmc)Co3+ in the presence of O2.

• Journal of Electrochemical Science and Technology
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• v.4 no.3
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• pp.89-92
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• 2013

Poly (3,4-ethylenedioxythiophene) (PEDOT) polymers with different electric conductivities were synthesized directly on a FTO substrate via a chemical polymerization method and applied as a platinum (Pt)-free counter electrode for dye-sensitized solar cells (DSSCs). The catalytic properties of the PEDOT as a function of electrical conductivity were studied using cyclic voltammograms, J-V measurements and impedance spectroscopy. The PEDOT counter electrode with around 340 S/cm conductivity exhibited the best performance as a counter electrode for tri-iodide reduction. The ability to modulate catalytic activity of PEDOT with changes in conductivity shows one of promising routes for developing new counter electrode of Pt-free DSSCs.

• Journal of Electrochemical Science and Technology
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• v.1 no.2
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• pp.117-120
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• 2010

Materials used as fuel cell electrode should be light, high conductive, high surface area for reaction, catalytic surface and uniformity of porous structure. Nickel is widely used in electrode materials because it itself has catalytic properties. When used as electrode materials, nickel of only a few im on the surface may be sufficient to conduct the catalytic role. To manufacture the nickel with porous structure, Electroless nickel plating on carbon fiber be conducted. Because electroless nickel plating is possible to do uniform coating on the surface of substrate with complex shape. Acidic bath and alkaline bathe were used in electroless nickel plating bath, and pH and temperature of bath were controlled. The rate of electroless plating in alkaline bath was faster than that in acidic bath. As increasing pH and temperature, the rate of electrolee plating was increased. The content of phosphorous in nickel deposit was higher in acidic bath than that in alkaline bath. As a result, the uniform nickel deposit on porous carbon fiber was conducted.

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.493-495
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• 2005

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.281-286
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• 2005

We created a new graphite-Cu(II) electrode and found that the electrode could catalyze FADH$_2$ oxidation and FAD reduction coupled to electricity production and consumption, respectively. In a fuel cell with graphite-Cu(II) anode and graphite-Fe(III) cathode, the electricity was produced by coupling to the spontaneous oxidation of FADH$_2$ Fumarate and xylose were not produced from the enzymatic oxidation of succinate and xylitol without FAD, respectively, but produced with FAD. The production of fumarate and xylose in the reactor with FAD electrochemically regenerated was maximally 2- 5 times higher than that in the reactor with FAD. By using this new electrode with catalytic function, a bioelectrocatalysts can be engineered; namely, oxidoreductase (e.g., lactate dehydrogenase) and FAD can function for biotransformation without an electron mediator and second oxidoreductase for cofactors recycling.

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.205-210
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• 1995

Catalytic effects of various Schiff base metal(II) complexes on the reduction of thionyl chloride at glassy carbon electrode are evaluated by determining the kinetic parameters from cyclic voltammetry technique. The charge transfer process is affected strongly by the concentration of catalysts during the reduction of thionyl chloride. The catalytic effects are shown by both a shift of the reduction potential for thionyl chloride toward more positive direction and an increase in peak current. The diffusion coefficient value, Do, of the 8.17 ${\times}$ 10-9 $cm^2/s$ was observed at the bare glassy carbon electrode, whereas larger values (0.9-1.09 ${\times}$ 10-8 $cm^2/s$) were observed at the catalyst supported glassy carbon electrode. Significant improvements in the cell performance have been noted in terms of both exchange rate constants and current densities at glassy carbon electrode.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1338_1339
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• 2009

Dye-sensitized solar cell (DSC) consists of photo electrode, counter electrode and electrolyte. Photo electrode has titanium oxide layer with dye molecule to create electrons. And counter electrode is made of one layer that has catalytic ability for redox system such as the iodide/triiodide couple. Most DSC researchers use platinum as catalyst on counter electrode because platinum has good catalytic ability and conductivity. Platinum is doped on fluorine-doped tin oxide glass with different methods such as sputtering method, electrochemical method and so on. In this paper, we deposit platinum on counter electrode glass with two methods. One is the radio frequency (RF) sputtering method and the other is the chemical method with heating treatment. Finally, we compare the photovoltaic characteristics of DSCs that are assembled using two different counter electrodes.