• Journal of Electrochemical Science and Technology
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• v.3 no.1
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• pp.50-56
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• 2012

Nickel modified NiOOH electrodes were used for the electrocatalytic oxidation of ethanol in alkaline solutions where the methods of cyclic voltammetry (CV) and chronoamperometry (CA) were employed. In CV studies, in the presence of ethanol, an increase in the current for the oxidation of nickel hydroxide is followed by a decrease in the corresponding cathodic current. This suggests that the oxidation of ethanol is being catalysed through mediated electron transfer across the nickel hydroxide layer comprising of nickel ions of various valence states. Under the CA regime the reaction followed a Cottrellian behavior and the diffusion coefficient of ethanol was found to be $1{\times}10^7cm^2s^{-1}$.

• Macromolecular Research
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• v.9 no.3
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• pp.179-183
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• 2001

Cathode materials for the polymer electrolyte membrane fuel cell was prepared by electropoly-merization of aniline at carbon paper in the presence of copper tetrasulfonato-phthalocyanine (CuTsPc) and their electrocatalytic behavior was studied. The amount of polyaniline and CuTsPc in the carbon paper was determined by UV spectroscopy of residual solution in electrochemical cell. The redox process of the prepared electrodes was investigated with cyclic voltammetry. The highest reversible current density was observed at the electrode that contains 27.6 wt% of polyaniline and 19.7 wt% of CuTsPc. The morphology of composite electrode from SEM showed the presence of large cluster of polyaniline with CuTsPc, which should be more finely interpenetrated into macropores of carbon for the better electrocatalytic activity.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.786-790
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• 2004

2-Aminoethanethiol (aet) has been used to make self-assembled monolayer (SAMs) on gold electrodes, which are subsequently modified with 3,4-dihydroxy phenylalanine (dpa). Such modified electrodes having various types of Au/aet-dpa were employed in the electrocatalytic oxidation of NADH. The purpose of this study to characterize the responses of such modified electrodes in terms of the immobilization procedure, pH of the solution and applied potential. The reaction of the surface immobilized dpa with NADH was studied using the rotating disk electrode technique and a value of $2.2{\times}10^4M^{-1}s^{-1}$ was obtained for the second-order rate constant in 0.1 M Tris/$NO_3^-$buffer (pH=8.0). The hydration behavior of the films was characterized by quartz crystal microbalance. When used as a NADH sensor, the Au/aet-dpa electrode exhibited good sensitivity and an excellent correlation (r ${\geq}$ 0.99) for NADH concentration which extended to $3.8{\times}10^{-3}$ M.

• Journal of Electrochemical Science and Technology
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• v.9 no.4
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• pp.292-300
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• 2018

The electrocatalytic oxidative behavior of an antiarrhythmic drug, procainamide hydrochloride (PAH) at the gold electrode surface has been examined using different voltammetric methods like cyclic, linear-sweep and differential pulse voltammetry. Voltammograms obtained in this study reveal that the electrode exhibit excellent electrocatalytic activity towards oxidation of the drug. The parameters that can affect the peak current at different pH, scan rate and concentration were evaluated. The number of electrons transferred was calculated. The current displayed a wide linear response ranging from 0.5 to $30.0{\mu}M$ with a limit of detection of 56.4 nM. The impact of potential interfering agents was also studied. The electrode displayed wide advantages such as simple sample preparation, appreciable repeatability, reproducibility and also high sensitivity. Furthermore, the feasibility of the proposed method was successfully demonstrated by determining PAH in the spiked human biological sample.

• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.56-56
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• 2002

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.45-45
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• 2000

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1301-1302
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• 2008

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.749-751
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• 2000

• Journal of the Korean Electrochemical Society
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• v.15 no.2
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• pp.83-89
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• 2012

We investigate the electrocatalytic activities for oxygen reduction at nanoporous gold (NPG) surfaces fabricated by selective dissolution of Ag from electrodeposited Ag-Au layers on electrode surfaces. The structure of NPG was controlled by changing the concentration ratios of precursor metal complexes during the electrodeposition of Ag-Au layers and the corresponding surface morphology and surface area was examined. NPG structures with Ag/Au ratio of 2.0 exhibited the highest electrocatalytic activity for oxygen reduction, where the nanoporous structure plays a key role, but the surface area does not affect on the electrocatalytic activity. The mechanism of electroreduction of oxygen was investigated by rotating disk electrode techniques. In acidic media, oxygen was first reduced to hydrogen peroxide followed by further reduction to water through 2-step 4-electron mechanism, whereas the oxygen was reduced directly to water by 4-electron mechanism in basic media.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.3
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• pp.194-201
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• 2009

The e1ectrocatalytic properties of heteropolyacids(HPAs) entrapped in covalently cross-linked sulfonated polyetheretherketone(CL-SPEEK/HPA) membranes have been studied for water electrolysis. The HPAs, including tungstophosphoric acid(TPA), molybdophosphoric acid(MoPA), and tungstosilicic acid(TSiA) were used as additives in the composite membranes. The MEA was prepared by a non-equilibrium impregnation-reduction(I-R) method, using reducing agent, sodium borohydride(NaBH4) and tetraamineplatinum(II) chloride(pt(NH$_3$)$_4$Cl$_2$). The electrocatalytic properties of composite membranes such as the cell voltage were in the order of magnitude CL-SPEEKlMoPA40 (wt%) > /TPA30 > /TSiA40. In the optimum cell applications for water electrolysis, the cell voltage of PtlPEM/Pt-Ru MEA with CL-SPEEKlTPA30 membrane was 1.75 V at 80$^{\circ}$C and I A/cm$^2$ and this voltage carried lower than that of 1.81 V of Nafion 117. Consequently, in regards of electrochemical and mechanical characteristics and oxidation durability, the newly developed CL-SPEEKITPA30 composite membrane exhibited a better performance than the others, but CLSPEEKlMoPA40 showed the best electrocatalytic activity (1.71 Vat 80$^{\circ}$C and 1 A/cm$^2$) among the composite membranes.