Photocatalytic performance of TiO2/V2O5 nanocomposite powder prepared by DC arc plasma

• We synthesized photocatalytic TiO2/V2O5 nanocomposite by DC arc plasma.
• Smaller V2O5 nanoparticles were attached on a larger TiO2 nanoparticle.
• Synthesized TiO2/V2O5 nanocomposite absorbs both of UV and visible lights.
• Synthesized TiO2/V2O5 nanocomposite can decompose Rhodamine B solution.
• Toluene was effectively decomposed by the synthesized TiO2/V2O5 nanocomposite.

TiO2/V2O5 nanocomposite powder was synthesized by the DC arc plasma, and its photocatalytic activity was examined by decompositions of Rhodamine B solution and toluene gas. In the synthesis of TiO2/V2O5 nanocomposite powder, TiCl4 and VOCl3 precursors were introduced into thermal plasma flame with argon carrier gases through separated two gas bubblers. They were decomposed by Ar–N2 thermal plasma generating Ti and V vapors, followed by the formation of oxides with the injection of additional oxygen into a plasma reactor. Nanocomposite composed of relatively small size V2O5 nanoparticles on a spherical TiO2 nanoparticle which was about 250 nm in diameter was identified by X-ray diffractometry, electronic microscopy, and energy dispersive spectroscopy when the ratio of carrier gas flow rates for TiCl4 to VOCl3 was 1:4 or 1:5. In ultraviolet–visible absorption spectroscopy, the absorbed wavelength of light for synthesized TiO2/V2O5 nanocomposite powder was wider than that for commercially available TiO2 nanopowder. Therefore, Rhodamine B solution exposed to visible light was decomposed by TiO2/V2O5 nanocomposite, whereas it was not decomposed by TiO2 nanopowder. In addition, toluene decomposition in a dielectric barrier discharge reactor was carried out with nano-sized photocatalysts of TiO2 nanopowder and TiO2/V2O5 nanocomposite. Relatively higher removal rate of toluene was found in the case of TiO2/V2O5 nanocomposite in virtue of improved photocatalytic performance.