Development of Fe/TiO2 Photocatalyst for Hydrogen Production from Water under Visible Light

Solar energy is concerned in order to generate hydrogen (H2) from water with the present of photocatalyst. The main problem is that current titanium dioxide (TiO2) photocatalyst is only active in the ultraviolet (UV) region. In order to harvest the abundance solar radiation consisting mainly of visible light, the efficiency of TiO2 has to be increased by shifted the absorption edge of TiO2 to the visible region. In order to increase the efficiency, the TiO2 photocatalyst is modified via metal doping method. The production of hydrogen over iron-doped titanium dioxide (Fe/TiO2) photocatalyst prepared by precipitation method has been studied. The iron (Fe) loading varied from 0.1 to 1.0 wt% with different calcination temperature at 300oC, 400oC and 500oC. The photocatalyst was characterized by Thermogravimetric Analysis (TGA), Diffuse Reflectance UV-Vis (DR UV-Vis), Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD), and Field Emission Scanning Electron Microscopy (FE-SEM). The UV–vis absorption spectrum indicated that the absorption edge of the photocatalyst red-shifted to around 600 nm. The lowest reduction of band gap as a result of Fe doping was obtained at 1.0wt% Fe/TiO2 calcined at 500oC (3.08 eV) compared to pure TiO2 (3.20 eV). Photocatalytic activity towards H2 generation from water was investigated using a multiport photocatalytic reactor by using halogen lamp that represented solar radiation. Under the irradiation with ultraviolet and visible light, the photocatalyst showed good performance for H2 production at 1,0 wt% of Fe loading calcined at 500oC with the production rate of 6.9 mL. The other characterizations of the photocatalyst were explained throughout this report.