• Carbon letters
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• 제18권
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• pp.43-48
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• 2016

Sulphonated polysulphone (SPS) has been synthesized and subsequently applied as binder for graphene oxide (GO)-based electrodes for development of electrochemical supercapacitors. Electrochemical performance of the electrode was investigated using cyclic voltammetry in 1M Na₂SO₄ and 1M KOH solution. The fabricated supercapacitors gave a specific capacitance of 161.6 and 216.8 F/g with 215.4 W/kg and 450 W/kg of power density, in 1M Na₂SO₄ and 1M KOH solutions, respectively. This suggests that KOH is a better electrolyte than Na₂SO₄ for studying the electrochemical behavior of electroactive material, and also suggests SPS is a good binder for fabrication of a GO based electrode.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.569-572
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• 2001

Selective, highly stable determination of epinephrine(adrenalin) was achieved in cyclic voltammetric measurement carried out at electrochemically treated conductive boron-doped diamond electrode. Boron-doped diamond electrodes were prepared on single crystal Si wafers by microwave plasma chemical vapor deposition and B$_2$O$_3$ was dissolved in acetone/methanol(1:1) mixture solution so that the B/C weight ratio ca. 10$^3$ppm.. Epinephrine is a kind of catecholamines, which secreted from adrenal marrow cells. The serious problem to detection of epinephrine is the interference phenomena of electroactive constituent, including AA. In this study, electrochemical treatment of BDD was carried out to discriminate between epinephrine and AA responses. Experimental results showed that the peak potential of AA oxidation shift to the positive direction and the oxidation peak of epinephrine was unchanged. The effect of electrochemical treatment was maintained up to 40hrs.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.167-169
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• 2002

Selective, highly stable determination of serotonin was achieved in cyclic voltammetric measurement carried out at electrochemically treated conductive boron-doped diamond electrode. Boron-doped diamond electrodes were prepared on single crystal Si wafers by microwave plasma chemical vapor deposition and $B_2O_3$ was dissolved in acetone/methanol(9:1) mixture solution so that the B/C weight ratio ca. $10^4ppm$. Serotonin is a kind of indoleamines, which secreted from adrenal marrow cells. The serious problem to detection of serotonin is the interference phenomena of electroactive constituent, including AA. In this study, electrochemical treatment of HDD was carried out to discriminate between serotonin and AA responses. Experimental results showed that the peak potential of AA oxidation shift to the positive direction and the oxidation peak of serotonin was unchanged.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.286.2-286.2
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• 2013

기존의 이온성 고분자-금속 복합체(IPMC)는 백금(Pt)전극을 이온성 전기활성 고분자(Ionic electroactive polymer)인 나피온에 무전해 도금으로 만들어졌다. 본 연구는 백금전극을 그래핀으로 대체하여 투명 이온성 고분자-그래핀 복합체(IPGC)를 제작하였다. 그래핀은 근적외선 화학기상증착법(NIR-CVD)으로 전이금속 (Cu, Ni) 위에 탄화수소 가스(CH4)를 이용하여 성장하였다. 전이 금속위에 성장된 그래핀을 나피온 양쪽면에 van der Waals 결합력을 이용하는 습식 전이공정으로 전극을 형성하였다. IPGC는 면 저항(4-point probe), 투과도(UV/Vis spectrometer) 및 라만 분광법(Micro Raman spectroscopy)의 측정으로 그래핀 전극의 특성평가를 하였고, 전계방사 주사전자현미경(Field Emisson Scanning Electron Microscope; FE-SEM)을 사용하여 IPGC의 구조적 특성을 확인하였다. 제작된 IPGC의 성능은 백금전극을 이용한 IPMC의 변위(displacement), 힘(force), 작동 주파수(Operating frequency) 분석을 통해 비교 평가하였다.

• Bulletin of the Korean Chemical Society
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• 제18권5호
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• pp.496-500
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• 1997

Electrochemical behavior of mer-tris(2-pyridinethiolato)cobalt(Ⅲ) in dimethylformamide was studied on a platinum electrode by means of cyclic voltammetry, chronoamperometry, and chronocoulometry. It was found that the neutral complex molecule was electroactive between the potential region of 1.0 and - 1.2 V vs. a nonaqueous Ag/Ag+ electrode. The Co(Ⅲ) complex was reversibly reduced to Co(Ⅱ) species by one-electron transfer at about - 1.1 V, followed by an irreversible dissociation reaction. However, the oxidation process at around 0.8 V, was responsible for an irreversible two-electron transfer that occurred at a ligand site.

• Bulletin of the Korean Chemical Society
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• 제18권11호
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• pp.1149-1152
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• 1997

An enzyme electrode for the amperometric measurement of urea was prepared by co-immobilizing L-glutamate dehydrogenase and urease onto an Immobilon-AV affinity membrane attached to a glassy carbon electrode. The reduced nicotinamide adenine dinucleotide(NADH) was used as the electroactive species. The electrochemical oxidation of NADH was monitored at +1.0 volt vs. Ag/AgCl. The enzyme-immobilized electrode was linear over the range of 2.0 × 10-5 to 2 × 10-4 M. The response time of the electrode was approximately 3 min. and the optimum pH of the enzyme immobilized membrane was pH 7.4-7.6 (Dulbcco's buffer solution). It was stable for at least two weeks or 50 assays. There was no interference from other physiological species, except from high levels of ascorbic acid.

• 대한화학회지
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• 제63권5호
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• pp.352-359
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• 2019

The most important parameter of organic molecules for energy harvesting application focuses mainly on their band gap (HOMO-LUMO). In this report, we synthesized differently substituted 1,3,5-triazine based organic molecule which on future processing can be used in organic electronics like solar cells and OLED's. The energy gap of the synthesized novel analogue was calculated using cyclic voltammetry, UV-Visible spectroscopy and compared with density functional theory (DFT) studies.

• Journal of Electrochemical Science and Technology
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• 제9권4호
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• pp.301-307
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• 2018

The current study fabricated magnetic functional reduced graphene oxide (MFRGO) by relying on ${FeCl_4}^-$ magnetic anion confined to cationic 1-methyl imidazolium. Furthermore, for improving the electrochemical performance of conductive polymer, hybrid poly ortho aminophenol (POAP)/ MFRGO films have then been fabricated by POAP electropolymerization in the presence of MFRGO nanorods as active electrodes for electrochemical supercapacitors. Surface and electrochemical analyses have been used for characterization of MFRGO and POAP/ MFRGO composite films. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. Prepared composite film exhibited a significantly high specific capacity, high rate capability and excellent cycling stability (capacitance retention of ~91% even after 1000 cycles). These results suggest that electrosynthesized composite films are a promising electrode material for energy storage applications in high-performance pseudocapacitors.

• Bulletin of the Korean Chemical Society
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• 제22권3호
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• pp.281-287
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• 2001

Self-assembled monolayers (SAMs) of the alkylthiols with [Os(bpy)3]2+ moiety at the terminal position were prepared on gold electrode surface. Examination of the cyclic voltammograms for the SAM shows that it does not organiz e well unlike alkylthiols, which is attributed to the much larger diameter of [Os(bpy)3]2+ moiety compared with the cross-section of alkyl chains and the distance between the adsorption sites. Electromicrogravimetry study shows that the hydration numbers of the electrolyte were 16 $\pm2$, 11 $\pm1$, 5 $\pm$ 1 and 24 $\pm6$ for ClO4- , PF6-, NO3- , and SO42- , respectively. The binary SAMs of alkylthiols with [Os(bpy)3]2+ terminal-group were prepared by co-adsorption of alkylthiols as spacer molecules, which results in better packing in SAM and accordingly the stability was enhanced.

• Bulletin of the Korean Chemical Society
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• 제27권3호
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• pp.381-385
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• 2006

The temperature dependence on the electron transfer rate constant $(k_{app})$ for hydroquinone redox center in $H_2Q(CH_2)_n$SH-SAMs (n = 1, 4, 6, 8, 10, and 12) on gold electrode was investigated to obtain reorganization energy $(\lambda)$ using Laviron’s formalism and Arrhenius plot of ln $[k_{app}/T^{1/2}]$ vs. T^{-1} based on the Marcus densityof-states model. All the symmetry factors measured for the SAMs were relatively close to unity and rarely varied to temperature change as expected. The electron tunneling constant $(\beta)$ determined from the dependence of the $k_{app}$ on the distance between the redox center and the electrode surface gives almost the same $\beta$ values which are quite insensitive to temperature change. Good linear relationship of Arrhenius plot for all $H_2Q(CH_2)_n$SH-SAMs on gold electrode was obtained in the temperature range from 273 to 328 K. The slopes n Arrhenius plot deduced that $\lambda$ of hydroquinone moiety is ca. 1.3-1.4 eV irrespectively of alkyl chain length of the electroactive SAM.