cathode

A cathode is an electrode in an electrochemical system or electrical circuit that accepts electrons during electrochemical reactions. In an electrolytic cell, electrolytic cell or galvanic cell, the cathode is the place where the reduction half-reaction takes place, that is, the acceptance of electrons.

In an electrolytic cell or electrolytic cell, where electrolysis takes place, the cathode is connected to the negative pole of the voltage source. When an electric current is applied through the electrolyte, reduction occurs at the cathode, which means that the electrodes receive electrons and a chemical reaction takes place. Thus, compounds or reduction products are formed at the cathode.

In a galvanic cell, where a spontaneous electrochemical reaction takes place, the cathode is where oxidation takes place, meaning that the electrodes release electrons into the surroundings. At the cathode, the products coming from the anode are reduced, thus maintaining the electrical balance in the system.

The cathode has a negative charge in electrochemical systems and is where the reaction takes place that ensures the flow of electrons. It is an important part of electrochemical processes and finds application in various applications, such as electrolysis, galvanic cells, accumulators, electrochemical reactors and others.

In electrochemistry, the term cathode (κάθοδος (kathodos), 'descent' or 'way down') refers to the electrode on which reduction takes place. When an external voltage is applied to the electrodes (in electrolysis), the cathode has a negative charge, in the case of an electric cell it has a positive charge.

In electronics, this name can be found with components such as a diode, tube or thyristor, where the cathode is usually the electrode with a negative voltage. In the case of a semiconductor diode, the cathode is an N-type semiconductor and is connected to a negative voltage in the forward direction.

The opposite of the cathode is the anode.