Since the
utilisation of light sources with wavelengths shorter than 300 nm
facilitates the generation of more reactive oxidising radicals by
direct irradiative decay of ozone and hydrogen peroxide (R3) and
(R4) in addition to surface reactions with photoinduced electron–
hole pairs, it is reasonable to conclude that moving towards shorter
wavelengths should lead to an increased efficiency of the oxidation
system. However, Zou and Zhu [58] reported the use of UVC irradiation
instead of a UVA under the same experimental conditions did
not considerably improve the decolourisation efficiency (84.3% vs.
87.2%) and TOC removal (34.3% vs. 37.3%) of a real wastewater
sample. Unfortunately, this effect was not investigated for photocatalytic
ozonation of other pollutants.