Preparation of metal ion (Fe3+ and Ni2+) doped TiO2 nanoparticles supported on ZSM-5 zeolite and investigation of its photocatalytic activity

Metal ion doped TiO2 nanoparticles supported on ZSM-5 zeolite (M-TiO2/ZSM-5 composites, M = Fe or Ni) were synthesized by hydrothermal method. The prepared composites were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis diffuse reflectance spectra (DRS). The photocatalytic activities of composites were evaluated by degradation of yellow GX aqueous solution under ambient condition. Fe-TiO2/ZSM-5 composite showed to be more efficient catalyst for degradation of dye molecules as compared with Ni-TiO2/ZSM-5 and TiO2/ZSM-5. Its higher photocatalytic activity is attributed to the effective separation of charge carriers that will be discussed in this paper in detail.

► Doping of TiO2 by Ni2+ and Fe3+ inhibits the growth of TiO2 crystals. ► Creation of mid band gap states leads to a red shift for doped TiO2/ZSM-5. ► Fe3+ doped TiO2/ZSM-5 exhibits the best photocatalytic activity. ► Fe3+ ions decrease recombination of electron–hole pairs.