Photocatalytic degradation of lindane under UV and visible light using N-doped TiO2

Nitrogen doped titanium photocatalysts with different nitrogen containing organic compounds were prepared by sol–gel method in acidic media. Among different nitrogen containing organic compounds, triethylamine doped TiO2 showed better photocatalytic activity under visible light. XRD, SEM and TEM analyses showed that the crystalline size of N-doped TiO2 was in the range of 20–24 nm. XRD and Raman spectrum showed that all peaks of N-doped TiO2 correspond to anatase crystalline structure. The formation of O–Ti–N bond in N-doped TiO2 does not lead to any new Raman band. XPS study confirmed that N replaces the O in the lattice of TiO2 and is present in the form of O–Ti–N. The photocatalytic activity of doped TiO2 was measured under UV and visible light using lindane as a target pollutant. The photocatalytic activity of anatase TiO2 and N-doped TiO2 was compared with commercially available Degussa P-25 TiO2. Intermediates formed during the degradation of lindane were monitored by GC–MS analysis.