title: Hydrothermal synthesis of ionic liquid [Bmim]OH-modified TiO2 nanoparticles with enhanced photocatalytic activity under visible light.
abstract: TiO(2) nanocomposites modified with the ionic liquid [Bmim]OH are synthesized by a hydrothermal procedure. X-ray diffraction, Zeta-potential measurement, TEM, thermogravimetric analysis, photoluminescence, UV/Vis, FTIR, and X-ray photoelectron spectroscopy are used to characterize the TiO(2) nanocomposites. The TiO(2) nanocomposites consist of pure anatase particles of about 10 nm. The modification of [Bmim]OH on the surface of the TiO(2) particles extends the TiO(2) absorption edge to the visible-light region. The electrochemical redox potentials indicated that the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of [Bmim]OH match well with the valence band (VB) and conduction band (CB) of the TiO(2) semiconductor. [Bmim]OH-modified TiO(2) is much more active than pristine TiO(2) under visible-light irradiation in the photocatalytic degradation of methylene blue in aqueous solution. [Bmim]OH is chemically bonded to the surface Ti-OH of TiO(2) particles rather than adsorbed on the surface. A possible mechanism for the photocatalysis is proposed.
authors.affiliation: State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012, China.
authors.forename: Shaozheng
authors.initials: S
authors.lastname: Hu
authors.forename: Anjie
authors.initials: A
authors.lastname: Wang
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.forename: Yao
authors.initials: Y
authors.lastname: Wang
authors.forename: Holger
authors.initials: H
authors.lastname: Löwe
mesh_terms: D002384:Catalysis; D052578:Ionic Liquids / Q000138:chemical synthesis* / Q000737:chemistry; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D055668:Photochemical Processes; D056951:Photoelectron Spectroscopy; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D014025:Titanium / Q000737:chemistry*
chemical_list: D052578:Ionic Liquids; C009495:titanium dioxide; D014025:Titanium