Voltammetry is an electroanalytical method in which the current is measured as a function of applied potential. The current vs potenitial plot (voltammogram) gives the information of the anlayte used for measurement. In a typical electrochemical cell with the 3-electrode configuration, the potential is applied to the working electrode with respect to a reference electrode, and an auxiliary electrode is used to complete the electrical circuit. The working in general is made of noble metals (platinum or gold) or carbon (i.e., glassy carbon), the auxiliary/counter electrode a Pt wire. The reference reference electrodes can be either Ag/AgCl electrode (Eo = 0.20 V vs. SHE) or saturated calomel electrode (SCE, Eo = 0.25 V vs. SHE).