Definition - What does Electrolytic Cell mean?
An electrolytic cell is an electrochemical cell that has undergone a reduction-oxidation reaction with the application of electrical energy. It is commonly used in the decomposition of chemical compounds in the process of electrolysis or breaking up of particles.
Electrolytic cells work within the chemical system by pushing electrical currents throughout the system. The process of electrolysis serves as the driving force of the redox reaction toward a direction that will not happen at the same time. Knowledge of electrolytic cells helps in understanding phenomenons like overvoltage that can occur within an electrolytic cell. Overvoltage or overpotential can be increased to reduce the corrosion rate.
Corrosionpedia explains Electrolytic Cell
Ions, when added to acidic or salt water, can be subjected to the process of electrolysis. When this is driven using an additional voltage source, positive hydrogen ions flow into the cathode and join the electrons to produce hydrogen gas throughout the reduction process. Similarly, oxidized hydrogen ions flow to anodic matter to free electrons and positive hydrogen ions produce oxygen within an oxidation type of reaction.
From this, it is apparent that electrolytic cells are used as the basis of electrochemical corrosion where two half-reactions are involved: reduction reaction (cathode) and the oxidation reaction (anode). There are various cathodic and anodic reactions that occur for alloys exposed in certain environments. The half-cell type reactions are believed to take place at atomic cathodes and anodes, coating a surface undergoing corrosion. Cathodes and anodes that are macroscopic can build up as the damage or corrosion expands over time.
In an electrolytic cell, four essential components should be taken into account:
- Conducting environment or electrolyte
- Electrical connection that is present between the first two components
If one of these components is disabled or absent, the process of electrochemical corrosion is halted. With this, it is very clear that an understanding of such elements is essential in order to implement the best practices for corrosion control. It must be noted that electrochemical processes can be either good or bad.
For instance, unprotected iron can undergo rusting with water and air due to the electrochemical process. On the other hand, steel rods can be protected from the same process by utilizing magnesium rods to offer cathodic protection against corrosion.