Construction of Cells and Electrodes

Materials for the Construction of Cells and Electrodes. Materials used for the construction of cells should be usable over a wide temperature range, dimensionally stable, impervious to aqueous and organic solvents and reagents, durable, and easy to machine or fabricate. Another highly desirable property is for the material to be transparent so that the electrodes and the solution can be observed. 

The large variety of commercially available ground-glass joints, glass frits, and stopcocks, and the services of a glassblower make it easy to fabricate cells for special purposes, and a selected few of these are described in a later section. Most companies that sell electrochemical instrumentation offer a number of cells of different styles, as well as electrodes and other accessories. 

A number of plastics are used in electrochemical cells, and some of their pertinent physical and chemical properties are described in the following paragraphs and listed in Table 6.3. 

Teflon. The Teflon TFE polymer is prepared from tetrafluoroethylene by Du Pont it is white and nearly opaque except in thin sheets. Teflon FEP is a copolymer of tetrafluoroethylene and hexafluoropropylene, which is more readily molded and is translucent. The FEP polymer has more limited chemical 

TABLE 6.1 Chemical Composition and Thermal Properties of Common Laboratory Glasses 

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