In RR3 photodegradation, the effect
hydrothermal settings for temperature and time were found significant and the highest
removal percentages were 92 and 94% for 15 and 30 min UV irradiation, respectively. In
alachlor photodegradation, the effect of Fe-doping was found significant under both UV
and visible light irradiation. The highest removal percentages were 49 and 82% for 15 and
30 min of UV light irradiation, respectively, and 51% for 60 min of visible light irradiation.
Only anatase crystallite was found in catalysts with and without Fe. Energy band gaps
decreased with increasing Fe contents. The crystallite sizes of catalysts with 0.10 wt% Fe3+
content decreased with increasing hydrothermal time and temperature, while surface area
increased. Energy-dispersive X-ray spectroscopy technique was able to detect nitrogen
contents of about 10 wt% and X-ray absorption near edge structure was used to find the
oxidation states of Fe3+ and Fe3+/4+ in Fe–TiO2 as well.