3.4. Photocatalytic activity tests
The photocatalytic activities of the samples were evaluated
by measuring the decoloration of MO in aqueous solution under
visible and sun light irradiation. Organic compounds such as
MO are believed to be destroyed through direct oxidation by
the trapped holes or being attracted by hydroxyl groups [27].
Temporal changes in the concentration of MO were monitored byexamining the variations in maximal absorption in UV–Vis spectra
at 510.0 nm. The degradation percent have accounted as follows: