Electrochemistry can be defined as the study of phenomena at electrified interfaces. As such, two things are fundamental to electrochemical measurements:
- Interface: boundary between two distinct, chemically different phases
- Electric field: existing across the interface
Generally, the interface occurs between a metallic conductor (the electrode) and a fluid, ionic conductor (the solution). The electric field usually results as a consequence of contact between a solid electrode and the solution. In electrochemistry, the electric field is most often one that is under user control, for example by utilizing a device called a potentiostat, which will be discussed in a later section.