Effect of iron, vanadium, and tungsten doped titania on BTEX photocatalytic decomposition

Abstract

Iron, vanadium, and tungsten doped TiO2 were synthesized via the solvothermal technique and immobilized onto fiberglass cloth (FGC). They were used in the photocatalytic decomposition of gaseous volatile organic compounds: benzene, toluene, ethylbenzene and xylene (BTEX) under visible light. The results were compared to that of the commercial pure TiO2 (P25). All doped samples exhibited higher visible light catalytic activity than the P25. The V-TiO2 showed the highest photocatalytic activity followed by the W and Fe doped samples with the highest conversion of 69% for 1163±12 ppm of gaseous toluene and 15, 68, 81, and 84% for 228±48 ppm of mixed BTEX, respectively. The results corresponded to the UV-Vis diffuse reflectance spectra (UV-Vis DRS) revealing that V-TiO2 had the highest visible light absorption followed by the W and Fe doped samples. The X-ray diffraction (XRD) patterns indicated all doped samples to contain both anatase and rutile phases with majority (> 80%) being anatase. The transition metal (TM) dopants were well mixed into TiO2 lattice. The X-ray absorption near-edge structure (XANES) spectra of the Ti K-edge transition indicated that most Ti ions were in the Ti4+ with octahedral coordination but with increased lattice distortion from TM doped samples. Our results showed that the TM doped TiO2 were successfully synthesized and immobilized onto flexible fiberglass cloth suitable for treatment of gaseous organic pollutants under visible light