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-N-2 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. (C) 2014 Elsevier B.V. All rights reserved.