• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.295-298
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• 1998

We have investigated ionic conductivity and electrochemical stability of the electrolytes containing organic solvent. Ion conductivities were measured between 10 and 80$^{\circ}C$, and electrochemical stabilities were determined by cyclic voltammetry on glassy carbon, platinum and aluminum electrodes. Ionic conductivity of electrolyte(EC:DEC=1:1) with IM LiPF$\_$6/ shows better than that of the other electrolytes having Li salts. The IM LiBF$_4$-PC electrolyte exhibits good electrochemical stability. IM LiPF$\_$6/ (EC:DEC=1:1) and IM LiPF$\_$6/ (EC:DMC=1:1) electrolytes are used for the high capacity of battery system.

• 전기화학회지
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• 제12권1호
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• pp.75-80
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• 2009

The effect of polyoxometalate monolayers on the electrodeposition of Au nanoparticles (AuNPs) on glassy carbon (GC) surfaces was examined by electrochemical and scanning electron microscope techniques. The presence of $SiMo_{12}O^{4-}_{40}$-layers resulted in average particle sizes of ca. 60 nm, which is larger than AuNPs deposited on bare GC surfaces. AuNPs electrodeposited on $SiMo_{12}O^{4-}_{40}$-modified GC surfaces for 20 s exhibited the best electrocatalytic activity for oxygen reduction. This system exhibited similar or slightly better efficiency for oxygen reduction than a bare Au electrode. Rotating disk electrode experiments were also performed and revealed that the catalytic reduction of oxygen on AuNPs deposited on $SiMo_{12}O^{4-}_{40}$-modified GC electrodes is a two-electron process.

• 대한기계학회논문집B
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• 제20권5호
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• pp.1679-1688
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• 1996

Laser flash technique was applied to measure thermal properties of FGM made by a CVD method. System stability and reproducibility of this measuring system were proved and calibrated with glassy carbon used as reference material. Specimens was prepared by cutting FGM diagonally. Measurements were performed for a wide range of temperatures up to 1500K. Relative heat capacity of the FGM specimen was scattered with in $\pm$13% at room temperature and at high temperature above 1200K, and $\pm$3% at medium temperature range. On the other hand, thermal diffusivity data showed excellent reproducibility and stability through the whole temperature range. In conclusion, the multi-target radiometer can be applied to measure the thermal properties of non homogeneous materials like FGM.

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.2019-2024
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• 2014

NiCu alloys have been suggested as potential candidates for catalysts in glucose oxidation. In this study, NiCu alloys with different compositions were prepared on a glassy carbon substrate by changing the electrodeposition potential to examine the effect of Ni/Cu ratios in alloys on catalytic activity toward glucose oxidation. Cyclic voltammetry and chronoamperometry showed that NiCu alloys had higher catalytic activity than pure Ni and Cu catalysts. Especially, Ni59Cu41 had superior catalytic activity, which was about twice that of Ni at a given oxidation potential. X-ray analyses showed that the oxidation state of Ni in NiCu alloys was increased with the content of Cu by lattice expansion. Ni components in alloys with higher oxidation state were more effective in the oxidation of glucose.

• Nuclear Engineering and Technology
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• 제44권8호
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• pp.939-944
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• 2012

Deposition potential, deposition time, square wave frequency, rotation speed of the rotating disc electrode, and palladium concentration were studied on a Glassy Carbon Electrode (GCE) in 0.01M HCl for the determination of palladium in High Level Nuclear Waste (HLNW) by anodic stripping voltammetry. Experimental conditions were optimized for the determination of palladium at two different, $10^{-8}$ and $10^{-7}M$, levels. Error and standard deviation of this method were under 1% for all palladium standard solutions. The developed technique was successfully applied as a subsidiary method for the determination of palladium in simulated high level nuclear waste with very good precision and high accuracy (under 1 % error and standard deviation).

• Journal of Electrochemical Science and Technology
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• 제7권3호
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• pp.241-244
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• 2016

Anodic stripping voltammetry (ASV) is successfully applied in mM level detection of mercury ion in an electroplating bath which is currently used in preparing a cathodic electrolyzer. Glassy carbon electrode is used for the detection and the optimum condition obtained is 10 s deposition at −1.4 V vs. Ag/AgCl and stripping by scanning from −1.4 to +0.4 V vs Ag/AgCl at 50 mV/s. By applying the method, the mercury ion concentration in the electroplating bath could be successfully monitored during the plating.

• Bulletin of the Korean Chemical Society
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• 제25권6호
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• pp.829-832
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• 2004

The pure product of 2,3-diaminophenazine was prepared by the enzyme-catalyzed reaction of ophenylenediamine-$H_2O_2$-horseradish peroxidase and characterized by UV/Vis spectroscopy, IR spectroscopy and NMR spectroscopy. The electrochemical behaviour of 2,3-diaminophenazine on the glassy carbon electrode was studied. The interaction between 2,3-diaminophenazine and deoxyribonucleic acid was studied by cyclic voltammetry method and UV/Vis spectroscopy, which indicated that the interaction between them is intercalation. The influence of reacting time was also studied. The binding ratio of the 2,3-diaminophenazine-DNA complex is calculated to be 1 : 2 and the binding constant is to be $5.07{\times} 10^3L{\cdot}mol^{-1}$ at room temperature.

• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1763-1768
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• 2006

The application of poly(Co(II)-(1,8-diaminonaphthalene))(poly(Co-DAN)) and poly(1,8-diaminonaphthalene) (Poly(1,8-DAN)) to the electrocatalytic reduction of molecular oxygen was investigated, which were electrochemically grown by the potential cycling method on the glassy carbon electrodes. The reduction of oxygen at the polymer and its metal complex polymer coated electrodes were irreversible and diffusion controlled. The Poly(1,8-DAN) and Poly(Co-DAN) films revealed the potential shifts for the oxygen reduction to 30 mV and 110 mV, respectively, in an aqueous solution, compared with that of the bare electrode. Hydrodynamic voltammetry with a rotating ring-disk electrode showed that Poly(1,8-DAN) and Poly(Co-DAN) coated electrodes converted respectively 84% and 22% of $O_2$ to $H_2O$ via a four electron reduction pathway.

• Bulletin of the Korean Chemical Society
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• 제19권4호
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• pp.417-422
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• 1998

The electrocatalytic reduction of molecular oxygen was investigated with a Co(II)-glyoxal bis(2-hydroxyanil) complex coated-glassy carbon (GC) electrode in aqueous media. The reduction of $O_2$ at the modified electrode was an irreversible and diffusion-controlled reaction. The complex coated-GC electrode demonstrated an excellent electrocatalytic effect for $O_2$ reduction in an acetate buffer solution of pH 3.2. The coated electrode made the $O_2$ reduction potential shift of 60-510 mV in a positive direction compared to the bare GC electrode depending on pH. The Co(II)-glyoxal bis(2-hydroxyanil) coated electrode converted about 51% of the $O_2$ to $H_2O_2$ via a two-electron reduction pathway, with the balance converted to H_2O$.

• Bulletin of the Korean Chemical Society
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• 제15권12호
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• pp.1054-1058
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• 1994

Different behavior on the formation of soluble intermediate was observed depending on the substrate employed during the nucleation of lead dioxide from plumbous ion using a rotating ring-disk electrode. It was found that no soluble intermediate was formed at glassy carbon electrode, while the presence of soluble intermediate could be detected at platinum substrate. From the different anodic behavior of two substrates, the formation of a probable Pb(Ⅲ) soluble intermediate was suggested. A most probable nucleation mechanism at the platinum substrate involving a second order chemical reaction was derived on the basis of rotating disk electrode experiments.