Enhanced visible-light photocatalytic activity of V2O5/S-TiO2 nanocomposites

Synthesis, luminescence and photocatalyst properties of zirconia nanosheets by modified Pechini method

“…Nanomaterials showed excellent photocatalytic properties on the degradation of organic dyes, due the fact that their unique physical and chemical properties in comparison with those of their bulk counterparts, and their properties based on quantum size effects and high surface area.In recent years, many studies performed on the heterogeneous photocatalysis, where oxide semiconductors such as TiO 2 , ZnO, Fe 2 O 3 , ZrO 2 , CuO are applied [12][13][14][15][16][17][18][19][20][21][22], Nanocrystalline ZrO 2 as a typical semiconductor or insulator showed the excellent characteristics such as high surface area, porosity, surface defects, relatively wide band gap value (Eg~5.0 eV depending on synthetic approaches),the high negative value of the conduction band potential (with a conduction band potential of -1.0 V vs. NHE) [23],thermally stable (m.p.2680˚C), chemically inert, excellent physical and chemical properties, non-toxicity, low thermal conductivity, high thermal expansion coefficient, high thermal shock resistance, polymorphic nature, low cost and easy availability [24].…”

The advanced removal of benzene from aerosols by photocatalytic oxidation and adsorption of Cu–TiO 2 /PU under visible light irradiation

“…The formation of Ti 3+ in the Cu-TiO 2 /PU could be due to the effect of the Cu dopant, which defected the TiO 2 lattice. The Cu doping led to the oxygen vacancies in the TiO 2 lattice, resulting in the reduction of Ti 4+ into Ti 3+ [44,45]. Ti 3+ could more easily generate excited electrons than Ti 4+ because the electron number of Ti 3+ (19) is higher than that of Ti 4+ (18), and thus the electrons in Ti 4+ are more strongly bound to the titanium nuclei than those in Ti 3+ [46].…”

Novel adsorption and photocatalytic oxidation for removal of gaseous toluene by V-doped TiO2/PU under visible light

“…The formation of Ti 3+ ions in the V-TiO 2 /PU materials could be due to the doping effects of V 4+ , which shares some oxygen atoms with titanium in the TiO 2 lattice to form a Ti O V bond, leading to oxygen vacancy in the lattice [31,32]. The oxygen vacancy in the TiO 2 lattice was the main reason for the reduction of Ti 4+ into Ti 3+ [25,32]. The Ti 3+ /Ti 4+ ratios in the V-TiO 2 /PU samples were also calculated and shown in Table 1.…”

“…In V-TiO 2 /PU, the titanium was found to exist in the forms of Ti 3+ and Ti 4+ , while vanadium existed in the forms V 4+ and V 5+ , creating a mixture of various different Fermi levels, as shown in Fig. 7 [26,32,34]. When considering the mixture of Fermi levels, the low energy levels provided by incident visible light could be utilized to transfer electrons from the valence band (O 2p Fermi level) to the intermediate Fermi levels of V 4+ 3d, Ti 3+ 3d and V 5+ 3d, and finally, to the conduction band (Ti 4+ 3d), in series (Fig.…”