Synthesis of excellent visible-light responsive TiO_2 − xN_yphotocatalyst by a homogeneous precipitation-solvothermal process

Abstract

Anatase, brookite and rutile type nitrogen-doped titania nanocrystals (TiO 2 2 x N y ) which are beige in color were successfully prepared by a 'Homogeneous Precipitation-Solvothermal Process' (HPSP) in TiCl 3 -hexamethylenetetramine (C 6 H 12 N 4 ) aqueous and alcohol solutions. The phase composition, crystallinity, microstructure, specific surface area, nitrogen doping amount and photocatalytic activity of titania powders greatly changed depending on pH, temperature and the type of treatment alcohols. The TiO 2 2 x N y powders showed excellent visible-light absorption and photocatalytic activity for nitrogen monoxide destruction under irradiation by both visible-light and UV-light. The beige titania powders prepared in TiCl 3 -hexamethylenetetramine alcohol solutions at 190 uC for 2 h possessed higher specific surface areas than those in aqueous solution. About 39 and 83% nitrogen monoxide could be continuously removed by the anatase TiO 2 2 x N y photocatalyst under irradiation of visible-light (l . 510 nm) and UV-light (l . 290 nm), respectively.

Brookite, the Least Known TiO2 Photocatalyst

“…N-doped mixtures of brookite and rutile obtained by using 1-propanol or 1-butanol as solvents were less active than N-doped brookite [137]. Instead, N-doped (anatase-brookite) samples obtained in methanol were more active than N-doped anatase or N-doped (anatase-rutile) mixtures for the degradation of methyl orange under visible light [189].…”

“…Yin et al [122,[136][137][138] prepared N-doped brookite nanoparticles by a solvothermal treatment at 190 °C of aqueous or alcoholic solutions of TiCl 3 and hexamethylenetetramine. The samples showed higher photocatalytic activity than that of P25 for the oxidative destruction of nitrogen monoxide under irradiation with visible light (λ > 510 nm) and UV-light (λ > 290 nm).…”

Promotion of Photocatalytic Activity of Titania by the Combination with Nitrogen-doped Titania

“…10 It is also accepted that the combination of two different band structure semiconductors could promote the photoinduced electrons-holes separation, which would lead to a greater increase of photocatalytic activity. 11 -13 In this research, the titanianitrogen-doped titania TiO 2 TiO 2 x N y composite with high photocatalytic activity was synthesized and characterized.…”

Evaluation of Photocatalytic Properties of Portland Cement Blended with Titanium Oxynitride (TiO2−xNy) Nanoparticles

“…This anionic partial substitution increases the range of the solar spectrum absorbed [14]. In this case, nanoparticles of TiOxNy can absorb wavelengths between 365 nm and 500 nm [15,16]. An approach of the behavior of these nanoparticles in building materials was done by mixing nano-TiO2−xNy with calcium carbonate (CaCO3).…”