Katodiskt

Katodiskt is an adjective used to describe phenomena, materials, or processes related to the cathode, the electrode where reduction occurs in electrochemical systems. In electrochemistry, the cathode is the electrode through which electrons flow into the solution and reduction takes place. In galvanic (voltaic) cells the cathode is typically the positive electrode, while in electrolytic cells it is the negative electrode. The term helps distinguish actions occurring at the cathode from those at the anode.

Common applications and concepts described as katodiska include katodisk avsättning, where metal ions in solution gain electrons and deposit as metal on the cathode. This process is fundamental to electroplating and electrodeposition, used to coat surfaces with a desired metal. Katodisk skydd, or cathodic protection, is a method to prevent corrosion of metal structures by making them the cathode of a galvanic couple or by applying an external current; as the cathode, they are protected from anodic dissolution.

Other contexts use katodiskt to refer to activities at the cathode in vacuum tubes and electron devices, where the cathode emits electrons (thermionic or field emission). In materials science and electrochemistry, katodiskt potential describes electrical potential references related to the cathode, often measured against a reference electrode.

Etymology: the term derives from the Greek kathodos, meaning the way down, with the root forming the contrast to anode (anodos, the way up). In Swedish usage, katodiskt aligns with the standard scientific terminology for cathode-related phenomena.