Nitrogen-doped TiO
2
was developed to enable photocatalytic reactions using the visible range of the solar
spectrum. This work reports on the synthesis, characterisation and kinetic study of interstitial N-doped
TiO
prepared by the sol–gel method using three different types of nitrogen dopants: diethanolamine, triethylamine
and urea. X-ray diffraction, scanning electron microscopy, transmission electron microscopy,
X-ray photoelectron spectroscopy and UV–visible spectroscopy were used to analyse the titania. Different
interstitial N-doped TiO
2
properties, such as absorption ability in the UV–visible light region,
redshift in adsorption edge, good crystallisation and composition ratio of titania structures (anatase and
rutile) could be obtained from different nitrogen dopants. Amongst investigated nitrogen precursors,
diethanolamine provided the highest visible light absorption ability of interstitial N-doped TiO
2
with
the smallest energy bandgap and the smallest anatase crystal size, resulting in the highest efficiency in
2-chlorophenol degradation. The photocatalytic activity of all N-doped TiO
can be arranged in the following
order: TiO
2
/diethanolamine > TiO
2
/triethylamine > TiO
2
2
/urea > un-doped TiO
. The initial rate of
2-chlorophenol degradation using the interstitial N-doped TiO
with diethanolamine was 0.59 mg/L-min
and the kinetic constant was 2.34 ×10
−2
min
−1
2
with a half-life of 98 min. In all cases, hydroquinone was
detected as a major intermediate in the degradation of 2-chlorophenol.
2
2