Effect of pH on the response of glassy carbon electrodes

The use of glassy carbon as an electrode material engenders a number of practical problems owing to the presence of C—O functionalities on its surface. One such problem is the susceptibility of the electrode to pH changes. Highly surface-active glassy carbon electrodes having a high proportion of irreversible C—O groups are particularly prone to variations in pH compared with ones having mainly quinoidal species. This is reflected in the performance of glassy carbon in the cyclic voltammetry of hydroquinone.