Measurement of a current:

The measurement of a current is done when the complete concentration polarization takes place in an electrochemical cell. Voltammetry has established from polarography. Polarography, as will be discussed in Unit 8, uses the DME as the working electrode. In voltammetry, the process of polarization is enhanced by using 'microelectrodes' as the working electrodes.

Thus, we can say that the electrochemical method in which the current is measured as a function of the potential applied to a microelectrode is known as voltammetry. These electrodes may be solid such as platinum, gold and glassy carbon or mercury. If the electrode is formed by a drop of mercury dropping from a fine glass capillary, the technique is called "Polarography"

Other forms of working electrodes used are hanging mercury dropping electrode (HMDE), static mercury drop electrode (SMDE), thin mercury film electrode (TMFE), glassy carbon electrode (GCE), carbon paste electrode (CPE), and many more. Working electrodes made of noble metals are used less frequently.