Since phenol is acidic and poor electron donor, the initial step during photodegradation is its adsorption onto the surface of clay followed by generation of electron–hole pair through absorption of UV light by nanosize ZnO semiconductor molecule intercalated between clay structures. This generated e− reduces dioxygen to superoxide radical which being unstable is neutralized in water generating hydroxyl radicals. These radicals are then converted into phenoxide radicals that responsible for the generation coupled product through nucleophilic attack on non-degraded phenol moiety in the solution (Scheme 1a). Such a mechanism results in the formation of 2,4,6-triphenoxy phenol (product a: m/e = 370.12) as one of the major intermediate formed during the photo degradation of phenol (Scheme 1b). It is well understood that superoxide radical is unstable due to low half-life period, significantly some of these radicals are also responsible for the generation of phenoxide radicals which undergoes opening of the cyclic benzene ring via intramolecular electron transfer process resulting in the formation of adipic acid as other degradation product (product b: m/e = 146.06). H atoms necessary for reduction of benzene structure and subsequent formation of aliphatic compound are generated from the reduction of H+ by photo-generated electrons [38].