Working Electrode Materials

Table 7 lists the electrochemical windows or the anodic stability limits of several nonaqueous electrolytes, or their anodic stabilty, the reference electrodes Rref used, the working electrode material Ew, the experimental conditions, and the references. It shows the following features ... 

Working electrode materials have an appreciable effect on the oxidation potentials and the resulting current densities (see also Ref. [139]). 

Figure 4a. Electrochemical cells for microwave conductivity measurements. Cell above microwave conduit (1) electrochemical cell (plastic tube, placed on working electrode material), (2) counter-electrode, (3) reference electrode, (4) electrolyte, (5) space charge layer, (6) diffusion layer, (7) contact to working electrode, (8) waveguide.

With respect to point 1, it has appeared that in oxidative detection, carbon is the best choice in nearly all cases. Therefore glassy carbon (an amorphous glass-like carbon) is the standard working electrode material in most cells for HPLC-EC. 

For reductive detection, however, and for some special oxidative applications, other materials perform better with respect to point 1, and usually a few experiments with different electrode materials are necessary to determine the optimum choice of working electrode material, see note in section Background Current in Chapter 2. 

Substance or Substance Class Detection Potential Working Electrode Material Reference Number... 

Rocklin, R. D. (1984). Working-electrode materials. Liquid Chromatogr. 2 588-594. 

A fundamental investigation of the anode electrode materials has been undertaken by Easton and Santhanam (Suppiah, 2008) for the five-step cycle (see Table 1). Their experiments employed three-electrode cell measurements using various working electrode materials. A 1 mM solution of... 

Three working electrode materials are commonly used in thin-layer amperometric detectors glassy (or "vitreous") carbon, carbon paste, and gold amalgamated with a thin film of mercury. 

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