The effect of milling atmospheres on photocatalytic property of Fe-doped TiO2 synthesized by mechanical alloying

The Fe-doped TiO2 powders were, respectively, milled in argon, air and oxygen atmospheres, the oxygen partial pressure (PO2PO2) of which increase in turn. The Fe concentration was found to be 4.468, 4.227 and 4.473 at.% for the powders milled in argon, air and oxygen, respectively. The rietveld refined of X-ray diffraction (XRD) revealed that the milled samples were pure rutile structure. The Raman spectra confirmed the results of XRD. Furthermore, it indicated that the amount of oxygen vacancies increased with the decrease of PO2PO2. Fe dissolved in TiO2 was found to take Fe2+/Fe3+ ionic valences. The absorption edge was shifted to visible light range by the doping of Fe. And visible light photocatalytic activity enhanced with the decrease of PO2PO2 due to the increase of oxygen vacancies.