High-temperature studies oxygen potential measurements

In all of the discussion of this chapter we have used an aqueous solution as the electrolyte, and electrodes suitable to those aqueous solutions. However, cells are not limited to aqueous solutions. Indeed, other solvents have been used for which liquid ammonia would be an example. Molten salts, such as mixtures of lithium chloride and potassium chloride, have been used for the study of cells at high temperatures. Some studies have been made at higher temperatures, in which solid electrolytes were used. Electrodes compatible with such solvents have also been devised. For example, a zirconium-zirconium oxide electrode stabilized with calcium oxide was used to measure the oxygen potential in nonstoichiometric metal oxides. However, no matter what the electrolytes or the electrodes are, the principles discussed in this chapter such as reversibility and proper measurement must be followed. 

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