Potentiometry

Potentiometry is an electroanalytical technique with which the concentration of an electroactive species in a solution can be determined using a reference electrode (an electrode with a known potential that is constant over time) and a working electrode (an electrode sensitive to the electroactive species) and a potentiometer.

There are different types of working electrodes useful for different cations or anions. Ion selective electrodes (ESI) or membrane electrodes are increasingly used. One of the most widely used, which came into use at the beginning of the XX century, is the pH electrode (a glass). Electrode types:

• Metallic electrode
• Glass membrane electrode
• Glass electrode
• Liquid membrane electrode
• Polymer membrane electrode

There are also different types of Indicator electrodes:

- Membrane electrodes:

• Vidrio
• Liquid Membrane
• Membrana Cristalina
• Gas

- Metallic Indicator Electrodes:

• Metals Inert
• First Species
• Second Species

Potentiometry is also used in different applications such as probes sensitive to gases or liquids, for potentiometric titrations.