Photocatalytic activity of different organic dyes by using pure and Fe doped SnO₂ nanopowders catalyst under UV light irradiation

A facile, chemical precipitation method has afforded highly crystalline iron (Fe) doped SnO₂ nanoparticles with efficient photocatalytic degradation of phenol and benzoic acid under ultraviolet light irradiation. Powder X-ray diffraction results show that the both pure and Fe doped SnO₂ samples are in tetragonal rutile type SnO₂ phase and the results are well matched with the standard data (card no. 41-1445). Transmission electron microscope reveals that the morphology of the samples was spherical in shape and the average particle sizes were around 24–42 nm, which is in good agreement with the XRD results. UV–VIS transmission spectroscopy studies show that the band gap energy of pure SnO₂ is 3.63, and 3.53, 3.34 eV for Fe-doped (3 & 5 wt%) SnO₂ nanoparticles respectively. Energy dispersive spectra (EDS) spectra confirm the presence of Fe in the most active Fe-modified SnO₂ sample. Fe-doped SnO₂ sample exhibited enhanced activity for both phenol and benzoic acid under ultraviolet irradiation, which could be due to the E_g decreased by Fe-doping, high specific surface area and porous structure. The samples were further characterized by Fourier transform infrared (FTIR) and photoluminescence spectra analysis. The photocatalytic mechanism of Fe doped SnO₂ also discussed.