Fe/TiO2: A Visible Light Active Photocatalyst for the Continuous Production of Hydrogen from Water Splitting Under Solar Irradiation

A series of Fe/TiO2 catalysts with varying amounts of Fe (0.2-2.0 wt%) were prepared by doping of Fe on the surface of nano TiO2. The XPS results revealed that Fe exists in Fe3+ state in a strong interaction with TiO2. The strong absorption band for Fe/TiO2 in the range of 440-575 nm infers the modification of TiO2 surface with Fe dopant. N-2 adsorption, TEM and SEM studies proved that the catalysts are mesoporous with high surface area and nanosized particle in size (a parts per thousand 5 nm). Photocatalytic activity of the catalysts was evaluated for the generation of H-2 from water splitting under solar irradiation. Optimisation of Fe3+ ion doped over the surface of TiO2 was studied, it is observed that 0.5 wt% Fe/TiO2 catalyst exhibited enhanced hydrogen yield of 270 mu mol-H-2/h activity, while un doped TiO2 shows 2.8 mu mol-H-2/h.The improved photocatalytic activity of Fe/TiO2 can be attributed to synergistic effects such as band gap in the visible region and minimum electron hole recombination over the surface by the formation of electron trapping centres.