Synthesis of Fe-doped TiO2 nanotubes by hydrothermal method for photodegradation of methylene blue from aqueous solutions

Fe-doped TiO 2 nanotubes were prepared by hydrothermal method using ferric nitrate and commercial TiO 2 powder. The obtained materials were characterized by means of XRD, TEM, BET, FT-IR and UV-Vis-DRS. The photocatalytic activity was evaluated based on photodegradation of methylene blue under visible light irradiation. The results show that Fe 3+ ions might incorporate into the lattice of TiO 2 nanotubes. Fe-doped TiO 2 materials showed narrower band gap energies, higher specific surface areas, more hydroxyl groups on the surface and significantly improved photocatalytic activity. The optimum Fe doping at the molar ratios of Fe/Ti = 0.5% showed the highest photocatalytic activity and was 3.08 times higher than that of undoped TiO 2 . The kinetic studies showed the decomposition of MB followed pseudo first-order kinetics with the rate constant were determined k app = 5.64×10 -2 min −1 .