Films Glassy Carbon

The electrochemical behaviour of trace concentrations of triphenylstannyl acetate, using a mercury film-glassy carbon electrode, was investigated by various measuring methods cyclic voltametry, differential pulse voltametry and controlled-potential electrolysis. Determination by DPASV (differential pulse ASV) of water and fish samples has LOD 2.5 nM98. 

Liu et al., 1998 [106] Milk Glucose oxidase (GOD)/ cross-linked with fi-cyclodextrin polymer. Coated with Nafion film Glassy carbon electrode/ +0.35 V vs. Ag/AgCl Ferrocene (also included in the polymer)... 

Svarc-Gajic J, Stojanovic Z (2010) Electrocatalytic determination of histamine on a nickel-film glassy carbon electrode. Electroanalysis 22 2931-2939... 

Biomass phenolic and furan resins polyimides glassy carbons, binder and matrix carbons" graphite films and monoliths activated carbons ... 

Cobalt(II) complexes of three water-soluble porphyrins are catalysts for the controlled potential electrolytic reduction of H O to Hi in aqueous acid solution. The porphyrin complexes were either directly adsorbed on glassy carbon, or were deposited as films using a variety of methods. Reduction to [Co(Por) was followed by a nucleophilic reaction with water to give the hydride intermediate. Hydrogen production then occurs either by attack of H on Co(Por)H, or by a disproportionation reaction requiring two Co(Por)H units. Although the overall I easibility of this process was demonstrated, practical problems including the rate of electron transfer still need to be overcome. " " ... 

By electrodeposition of CuInSe2 thin films on glassy carbon disk substrates in acidic (pH 2) baths of cupric ions and sodium citrate, under potentiostatic conditions [176], it was established that the formation of tetragonal chalcopyrite CIS is entirely prevalent in the deposition potential interval -0.7 to -0.9 V vs. SCE. Through analysis of potentiostatic current transients, it was concluded that electrocrystallization of the compound proceeds according to a 3D progressive nucleation-growth model with diffusion control. 

At the next level of abstraction are measurements performed at a thin film of fuel cell catalyst immobilized on the surface of an inert substrate, such as glassy carbon (GC) or gold (Fig. 15.2c). Essentially, three versions of this approach have been described in the fiterature. In the first case (a porous electrode ), an ink containing catalyst and Nafion ionomer is spread onto an inert nonporous substrate [Gloaguen et al., 1994 Gamez et al., 1996 Kabbabi et al., 1994]. In the second case (a thin-fihn electrode ), the ink does not contain Nafion , but the latter is... 

Many workers have tried to omit the mercury film by depositing the analyte directly on inert metals such as Pt, Au, Rh, Ir or Ag or on carbon materials such as glassy carbon or wax-impregnated graphite however, in general this was not successful (lack of selectivity for mixtures as a consequence of interdiffusion) and therefore it is rarely applied except for those nobler analyte metals that cannot be measured at mercury, such as Au, Ag and Hg itself. Nevertheless, metals such as Ni and Cr, which do not amalgamate, can be determined on an HMDE100. 

Since model compounds reveal well-defined cyclic voltammograms for the Cr(CNR)g and Ni(CNR)g complexes (21) the origin of the electroinactivity of the polymers is not obvious. A possible explanation (12) is that the ohmic resistance across the interface between the electrode and polymer, due to the absence of ions within the polymer, renders the potentially electroactive groups electrochemically inert, assuming the absence of an electronic conduction path. It is also important to consider that the nature of the electrode surface may influence the type of polymer film obtained. A recent observation which bears on these points is that when one starts with the chromium polymer in the [Cr(CN-[P])6] + state, an electroactive polymer film may be obtained on a glassy carbon electrode. This will constitute the subject of a future paper. 

Coordination of NO to the divalent tetrasulfonated phthalocyanine complex [Co(TSPc)]4 results in a complex formally represented as [(NO )Coin(TSPc)]4 kf= 142M-1s-1, KA 3.0 x 105 M-1). When adsorbed to a glassy carbon electrode, [Co(TSPc)]4- catalyzes the oxidation and reduction of NO with catalytic currents detectable even at nanomolar concentrations. Electrochemistry of the same complex in surfactant films has also been studied.905 Bent nitrosyl complexes of the paramagnetic trivalent tropocoronand complex Co(NO)(TC) ((189), R = NO) have also been reported.849... 

J.Z. Zhang and S.J. Dong, Cobalt(II)hexacyanoferrate film modified glassy carbon electrode for construction of a glucose biosensor. Anal. Lett. 32, 2925—2936 (1999). 

Z. Zhang, H. Liu, and J. Deng, A glucose biosensor based on immobilization of glucose oxidase in electropolymerized o-aminophenol film on platinized glassy carbon electrode. Anal. Chem. 68, 1632-1638 (1996). 

H. Luo, Z. Shi, N. Li, Z. Gu, and Q. Zhuang, Investigation of the electrochemical and electrocatalytic behavior of single-wall carbon nanotube film on a glassy carbon electrode. Anal. Chem. 73, 915—920... 

J. Qu, Y. Shen, X. Qu, and S. Dong, Preparation of hybrid thin film modified carbon nanotubes on glassy carbon electrode and its electrocatalysis for oxygen reduction. Chem. Commun. 1, 34—35... 

S. Lu, K. Wu, X. Dang, and S. Hu, Electrochemical reduction and voltammetric determination of metronidazole at a nanomaterial thin film coated glassy carbon electrode. Talanta 63, 653-657... 

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