Solvents aqueous and nonaqueous

The whole range of solvents (aqueous and nonaqueous) and supporting electrolytes (usually 0.1 M in order to avoid migration effects) including the popular tetra-alkyl ammonium salts are used in voltammetric studies. There are no particular restrictions from the voltammetric conditions. It must be noted, however, that for mechanistic studies high-purity electrolyte components are necessary. Since the substrates are often present in concentrations of 10 M or lower, even traces of impurities may have detrimental effects on the current-potential curves (see also Sect. 2.1.3.3). The choice of solvent and supporting electrolyte clearly depends on the application and factors such as solubility of the substrate. 

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