Modified 3D Ewald Summation for Slab Geometry at Constant Potential

Preparation and microscopy characterization of polymer modified glassy carbon electrodes based on (5-[(azulen-1-yl) methylene]-2-thioxothiazolidin-4-one (L) were reported. Atomic Force Microscopy was used to investigate the morphological and mechanical properties of the deposited polyL films onto glassy carbon. The topography images of the analyzed samples exhibited the presence of some columnar shape features onto the layer surfaces. The surface roughness of the layers deposited at constant charge calculated from topography images, increased with the more positive applied potential for controlled potential electrolysis. At different charges, the roughness parameter showed the same behavior for the layers obtained applying a constant potential without having a noticeable influence on the adhesion properties on the substrate. Analysis using scanning electron microscopy shows a relatively uniform surface arrangement of the polymer and the presence of some clusters which are disturbing the planarity. PolyL chemically modified electrodes have been used for heavy metal ions detection with best results for lead.

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New highly efficient coulometric cell with homogenous potential distribution on the working electrode

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19860636 ◽

1986 ◽

Vol 51 (3) ◽

pp. 636-642

Author(s):

Michal Németh ◽

Ján Mocák

Keyword(s):

Chemical Reactions ◽

Potential Distribution ◽

Anaerobic Conditions ◽

Highly Efficient ◽

Working Electrode ◽

Constant Potential ◽

Quantitative Analyses ◽

Mechanism And Kinetics ◽

Kinetics Of

A highly efficient coulometric cell was designed and constructed, ensuring a constant potential over the whole surface of the working electrode and suitable for very rapid electrolysis. It consists of concentric cylindrical Teflon parts; also the working and auxiliary electrodes are cylindrical and concentric. Electrolysis can be carried out under anaerobic conditions. Functioning of the cell was tested on the oxidation of hexacyanoferrate(II) and chlorpromazine and reduction of hexacyanoferrate(III). The new cell is suitable for routine quantitative analyses and in studying the mechanism and kinetics of moderately rapid chemical reactions.

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Influence of Partial Blocking of the Electrode Surface on the Transfer Coefficients

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19930496 ◽

1993 ◽

Vol 58 (3) ◽

pp. 496-505

Author(s):

Ondřej Wein

Keyword(s):

Surface Activity ◽

Elliptic Problem ◽

Electrode Surface ◽

Driving Force ◽

Two Dimensional ◽

Transfer Coefficients ◽

Constant Potential ◽

Numeric Solution ◽

Active Zones ◽

Partial Blocking

Partial blocking of the transport surface under the stagnant (nerst) layer is simulated by periodically alternating bands of perfectly insulating zones and active zones with a constant potential of driving force. The numeric solution of the corresponding two-dimensional elliptic problem is represented by a simple empirical correlation for the transfer coefficients. The result is interpreted in terms of a simple electrochemical problem about limiting diffusion currents at electrodes with non-uniform surface activity.

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