Explain the working principle of electrolytic capacitor.
Principle: Electrolytic capacitors are using a chemical feature of some special metals, on which by anodically oxidation, an insulating oxide layer or dielectric originates. The metal is placed in an electrolytic solution and a positive voltage is applied to the anode material. This forms a thin layer of oxide barrier layer on the anode. This oxide layer acts as dielectric in an electrolytic capacitor.This oxide film can be made extremely thin (typically less than 1µm) with a high dielectric constant. This increases the value of capacitance.Because of the use of the electrolytic process to form the thin oxide dielectric, this type of capacitor is called ‘electrolytic’.