Читать книгу Electroanalytical Chemistry - Gary A. Mabbott - Страница 22

Instrumental methods of electrochemical analysis depend upon chemical events at boundaries between two different phases. In potentiometric experiments, interesting processes give rise to a separation of charge at the boundary between the sample and sensor; in voltammetric experiments an outside power source applies a voltage to the working electrode creating a separation of charge that drives interesting processes there. It is common for charges to appear at many different phase boundaries in nature, for example, at the surface of biological cell walls, on the surface of water droplets or solid aerosols, and at the surface of wet materials such as ceramics, clays, sediments, and soils. The same electrochemical principles that are involved in electrochemical analysis drive lots of natural phenomena as well. One of the most important concepts that is universal is the boundary between two phases where charges accumulate. It is called the electrified interface or the electrical double layer.