Explanation:

Chlorofluro carbons

Depletion of ozone layer is mainly due to Chloroflorocarbons.
Note:
The following describes the destruction of the ozone by chlorofluorocarbons.
Chlorofluorocarbons contains the chlorine molecule which reacts with ozone (O3?) molecule and splits into O2? and O molecules.
Chlorofluorocarbons are used in refrigerators, air conditioners and aerosol sprays. They damage the ozone layer of the atmosphere.