What is the function of a cathode in an electrochemical cell?

The function of a cathode in an electrochemical cell is to serve as the electrode at which reduction occurs. In the context of electrochemical processes, reduction involves the gain of electrons by a species. At the cathode, electrons flow into the electrode from an external circuit and are gained by the ions in the electrolyte, leading to a reduction reaction. This is fundamental to the operation of batteries and electrochemical cells, where the cathode is typically the site of the chemical reduction processes that yield electrical energy.

In electrochemistry, clarity of terminology is crucial. While oxidation occurs at the anode, the cathode specifically plays the role of facilitating the reduction reaction, highlighting its essential function in the overall operation of the electrochemical cell. Understanding this distinction helps clarify how electrochemical systems function, including applications in corrosion prevention, energy storage, and electroplating.