enhancing photocatalytic activity of nitrogen doped tio2 for degradation of 4-chlorophenol under solar light irradiation

The nitrogen doped tio2 as a heterogeneous photocatalyst via sol-gel method was successfully synthesized. the as-synthesized photocatalysts were characterized with x-ray diffraction (xrd), surface area measurements (bet and bjh), fourier transform infrared spectroscopy (ft-ir), field emission scanning electron microscopy (fe-sem), energy dispersive spectroscopy (eds), and energy dispersive x-ray spectrum (edx). the activities of as-prepared tio2 photocatalysts were examined to degrade 4-chlorophenol aqueous solution under solar irradiation in a photoreactor; in addition, photocatalytic degradation mechanism and pathway were investigated. the results showed that 3 % wt n-doped tio2 nanoparticles (under conditions of solution ph of 4.0, catalyst loading of 2 g/l, initial 4-cp concentration of 10 mg/l, and irradiation time of 8 h) exhibited much higher photocatalytic degradation efficiency (91 %) as compared with that of 5 % wt n-doped (83 %), 1 % wt n-doped (71 %), and pure tio2 (35 %).