Photocatalytic oxidation of methyl orange by natural V-bearing rutile under visible light

Natural rutile, which contains substituting metal ions as V5+ and Fe3+, was found to exhibit good photoactivity in visible light. The result showed that 60.59% of methyl orange (MO) was photodegraded after 1 h visible light irradiation. Compared with P25 TiO2, the efficiency and mechanism of MO degradation by natural rutile was discussed. The visible light response was due to the substituting ions altering the band structure, and the effective photoactivity was related to the presence of H2O2 and surface hydroxyl groups. Moreover, the substituting metal ions in their high oxidation states could capture photogenerated electrons to suppress electron–hole combination.