elektrochemical

Electrochemical describes phenomena and technologies in which chemical changes are driven by or produce electrical energy. The field encompasses the study of redox reactions at interfaces between electrodes and electrolytes, including the transfer of electrons through an external circuit.

A typical electrochemical system consists of an anode, a cathode, an electrolyte, and often a separator. In galvanic (voltaic) cells, spontaneous redox reactions generate electrical energy. In electrolysis, applied electrical energy drives non-spontaneous chemical transformations. The cell potential is governed by the electrode potentials of the redox couples, and the Nernst equation relates potentials to concentrations and conditions.

Key concepts include electrode kinetics, overpotential, and the electrical double layer at the interface. Distinguishing Faradaic (charge-transfer) processes from non-Faradaic (capacitive) processes helps explain energy storage and reaction rates. Analytical techniques such as voltammetry, chronoamperometry, potentiometry, and electrochemical impedance spectroscopy probe reaction mechanisms, rate constants, and interfacial properties.

Applications span energy storage and conversion (batteries, supercapacitors, fuel cells, and water electrolysis), electroplating and metal finishing, corrosion protection, and electrochemical machining. Electrochemical sensing and biosensors exploit redox reactions at electrodes for detection. Environmental electrochemistry addresses remediation and water treatment, while electrochemical synthesis enables selective chemical production under mild conditions.

History and development trace from early work by Galvani and Volta to the formulation of Faraday’s laws and the broad adoption of electrochemical methods in science and industry. The field continues to influence energy technology, materials science, sensing, and environmental engineering.