• Journal of Integrative Natural Science
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• v.7 no.3
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• pp.188-192
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• 2014

Determination of cobalt(III) ion with a perfluorinated sulfonated polymer-ethylenediamine (nafion-en) modified glassy carbon electrode is studied. It is based on the chemical reactivity of an immobilized layer, nafion-en, to yield complex $[Co(en)_3]^{3+}$. The reduction peak potential by differential pulse voltammetry (DPV) is observed at $-0.437{\pm}0.047$ V (vs. Ag/AgCl). The linear calibration curve is obtained in cobalt(III) ion concentration range $1.0{\times}10^{-8}{\sim}1.0{\times}10^{-3}M$ ($5.893{\times}10^{-12}{\sim}5.893{\times}10^{-5}g/mL$).

• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.141-145
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• 2000

Anodically Polymerized conducting Polypyrrole film electrode was employed to Pick up uranyl ion with the type of Gr/ppy, xylenol orange modified electrode. To have Porous and oriented ppy film, NBR was applied as precoating agent. The rate constant of polymerization was $3.22\times10^{-3}s^{-1}$ which was 1.6 times smaller value than bare graphite surface. The deposited amount of uranyl iou on $1.70Ccm^{-2}$ of ppy was $1.55\times10^{-4}g$. The matrix effect in artificial seawater was $6.8\%$. The polymer film electrode has a diffusion controlled process in conduction, but the modified Gr/ppy, $X.O^{4-}UO^+$ type was influenced on the ion doping and electronic conduction of film itself owing to increasing of impedance. The capacitance of electrical double layer was respectively enhanced to 56 and 130 times in Gr/ppy, $X.O.^{4-}$ and Gr/ppy, $X.O^{4-}UO^+$ than Grippy type electrode.

• Journal of the Korean Chemical Society
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• v.32 no.5
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• pp.409-415
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• 1988

In this study, an aniline modified Bakelite-A resine was synthesized by polymerizing phenol, formaldehyde and aniline. Structural properties of the polymer were examined by IR spectroscopy, elemental analysis and vapour pressure osmometry. By visible spectroscopy, it was found that nitrogens of amine groups in the polymer are strongly coordinated to Ni(Ⅱ). Also a nitrate ion-selective PVC membrane electrode based on the polymer-Ni(Ⅱ) complex as ion carrier was preparaed. The electrode gave a linear response with a Nernstian slope within the concentration range $10^{-1}$ M∼$10^{-4}$M $KNO_3$.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.27-31
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• 2003

A Polythiophene-quinoline/glassy carbon (PTQ/GC) modified electrode was developed for the determination of trace mercury in industrial waste water, natural water, soil, and other media. The electrode was prepared by the cyclic voltammetric polymerization of thiophene and quinoline on glassy carbon (GC) electrode by the potential application from -0.6 V to +2.0 V (50 mV/sec) in a solution of 0.1 M thiophene, quinoline and tetrabutyl ammonium perchlorate (TBAP) in acetonitrile. Optimum thickness of the polymer membrane on the GC electrode was obtained with 20 repeated potential cyclings. The redox behavior of Cu(Ⅱ) and Hg(Ⅱ) were almost identical on this electrode. The addition of 4-(2-pyridylazo)resorcinol (PAR) to the solution containing Cu(Ⅱ) and Hg(Ⅱ) allowed the separation of the components due to the formation of the Cu(Ⅱ)-PAR complex reduced at -0.8V, which was different from the Hg(Ⅱ) reduced at -0.5 V on a saturated calomel electrode (SCE). The calibration graph of Hg(Ⅱ) shows good linear relationship with the correlation factor of 0.9995 and the concentration gradient of 0.33 ㎂/㎠/ppb down to 0.4 ppb Hg. The method developed was successfully applied to the determination of mercury in samples such as river, waste water, and sea water.

• Journal of the Korean Chemical Society
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• v.40 no.7
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• pp.467-473
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• 1996

Although a polypyrrole shows better electrical conductivity, 100∼400 ${\Omega}^{-1}cm^{-1}$, than other organic conducting polymers, its electrical conductivity will be worsen in the presence of the oxygen due to its easy oxidation. On the other hand, polythiophene shows better stability in the air while its electrcal conductivity is poor compared to the polypyrrole. We succeed to develope the mixed polymer electrode that is stable in the air and shows a good redox characteristics. The mixed polymer electrode has been prepared by the electrical polymerization of polypyrrole on the Pt electrode as 1.70 C$cm^{-2}$ and then coating with polythiophene as 0.34 C$cm^{-2}$. The polymerization rate of polythiophene was $3.89{\times}10^{-8}$ at the bare Pt electrode and $6.07{\times}10^{-8}cms^{-1}$ at the mixed polymer electrode. And the standard rate constants of each electrode were $5.16{\times}10^{-6}\;and\;3.94{\times}10^{-4} cms^{-1}$ respectively. Also, the electrocatalytic rate of the polypyrrole polymer electrode was $3.45{\times}10^{-3}cm^3mol^{-1}s^{-1}.$ We found the immobilized layer at the modified electrode acted as an electrocatalyst. Finally, this polymerization process at the Pt electrode was the electron transfer controlled, but that the mixed polymer electrode was the diffusion and charge transfer controlled.

• Journal of the Korean Vacuum Society
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• v.6 no.4
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• pp.321-325
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• 1997

Recently, photosensitive color filters have received much attention for their use in the liquid crystal display (LCD) industry. It is well known that chemical and physical properties of polymer surfaces can be modified by special surface treatments. In this work, we have studied the polymer surfaces of LCD blue color filters which were exposed to the UV light during photolithography. A better understanding of the irradiated polymer surfaces is required for the subsequent processes such as plasma etching, ITO electrode deposition, etc. The surface analysis has been undertaken using secondary ion mass spectrometry (SIMS), x-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). A significant enrichment of the pigment component and roughening of surface with bubble-like feature have been observed at the modified polymer surface.

• Journal of the Korean Chemical Society
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• v.45 no.5
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• pp.429-435
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• 2001

The monomer N,N'-bis(2-pyrrol-1-yl-propyl)-4,4'-bipyridine(bpb) was electrochemically polymerized on the glassy carbon electrode surface, which was modified with 1:1 ratio of erichrome black T(EBT) and glutathione(GSSG) to give a type of GC/poly-bpb, EBT, GSSG electrode for depositing Zn(II). The diffusion coefficients of the incorporated ions were 2.43${\times}10^{-15}$ and 9.14${\times}10^{-15} cm^2s^{-1}$ before taking Zn(II) ions and after them respectively. The modified electrodes are stable at the electrode process. The polymerized poly-bpb of 2.83${\times}10^4gmol^{-1}$ can deposit 2.15${\times}10^4gmol^{-1}$ of Zn(II). The number of pumping ions involving in the redox procedure at 0.77 V was 81.7% of the captured 180 ions into the polymer matrix, which was 3 times larger than that of the electrode modified with EBT alone.

• Journal of the Korean Chemical Society
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• v.49 no.1
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• pp.47-55
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• 2005

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.8
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• pp.847-854
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• 2007

The battery electrode of a mobile phone is made of layered polymer coated on aluminum foils and the hot rolling process is applied to increase the density per volume of an electrode for a high capacity battery. The flatness of batteries surfaces should be less than $2{\mu}m$. To satisfy the required flatness, the deformation of roll surface due to bending and heating of the roll should be minimized. Complicated hot oil paths of $100^{\circ}C$ inside the roll are required for heating the polymer layers. FEA was used to calculate thermal deformations and temperatures distributions of the roller. Based on FEA, a modified surface curvature called a crown roll was suggested and this gave the area of 30% improved flatness compared with a flat roll. The flat roll satisfied the flatness of $2{\mu}m$ in the length of 340 mm and the crown roll resulted in the longer length of 460 mm. Experiments to measure the temperature distribution and thermal strain were performed and compared with FEA. There were only 6% difference between two results.

• Journal of Electrochemical Science and Technology
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• v.5 no.1
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• pp.19-22
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• 2014

Here we report a highly sensitive and stable detection of $NAD^+$ and NADH by the electrode on which diaphorase (DI) is covalently immobilized in viologen polymer network. The network is prepared by the covalent formation of the structure by mixing propylamine viologen (PAV), poly(ethylene glycol)(400) diglycidyl ether (PEGDGE), an diaphorase (DI). The PAV/PEGDGE/DI modified electrode has the sensitivity of $0.02nA{\cdot}{\mu}M$ and the detection limit of $3{\mu}M$ with a response time of 2 s ($t_{90%}$) for NADH sensing.