Electrode materials for voltammetry

The experimental aspects to be discussed in this chapter include cell design, electrode materials, construction and cleaning of electrodes, solution composition, and control instrumentation. Electrode materials specially designed for potentiometric measurements, which rely on the material selectivity, are discussed in Chapter 13. 

We shall not give many practical details, but only those of greatest interest in the planning and design of electrochemical experiments. However, it is hoped that the discussion in this chapter will prove an aid to consulting more detailed expositions in this area, for example Refs. 1-6. 

The choice of an electrode material depends to a great extent on the useful potential range of the electrode in the particular solvent employed and the qualities and purity of the material. The usable potential range is limited by one or more of the following factors  

Additionally, solid electrodes can be adversely affected by poisoning through contact with solutions containing contaminants. We now consider some frequently used materials and look at their properties as electrodes in more detail. 

Much has been written about solid metal electrodes, which have now largely displaced liquid mercury. Those most often used as redox ( inert ) electrodes for studying electron transfer kinetics and mechanism, and determining thermodynamic parameters are platinum, gold, and silver. However, it should be remembered that their inertness is relative at certain values of applied potential bonds are formed between the metal and oxygen or hydrogen in aqueous and some non-aqueous solutions. Platinum also exhibits catalytic properties. 

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