TiO2, when employed as thin film on a substrate reduces the
disadvantages of heterogeneous photocatalysis such as stirring
which is required during the reaction to discourage agglomeration
of the particles and separation of particles after reaction
[12–15]. Kato et al. showed that factors such as the morphology
and crystal structure of TiO2 coatings, affect the photocatalytic
activity for aqueous acetic acid degradation