title: Preparation and characterization of mesoporous Ag/VO(x)-TiO2 employed for catalytic hydroxylation of benzene.
abstract: The V-based complex oxides were found to exhibit good catalytic reactivity for the selective oxidation of benzene to phenol. In order to understand the effect of the catalyst on the reaction, a series of Ag/VO(x)-TiO2 catalysts with different Ag loadings were prepared. Data from the X-ray diffraction (XRD), N2-adsorption isotherms, scanning electron microscopy (SEM), transmission electron microscopy (TEM), H2 temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS) showed the formation of complex oxides with phases of silver and vanadates, and the increased redox ability of vanadium species. The results from H2-TPR revealed that the addition of Ag promoted the reduction of vanadium species in the complex catalysts. The presence of Ag and Ag+ ions at the catalyst surface were proved independently by XPS measurements. The Ag and Ag+ ions also effectively strengthened the thermostability of the Ag/VO(x)-TiO2 catalyst, and the Ag species also made a strong contribution to the monodispersion of vanadium on the surface of the TiO2 carrier. The reactivity for the selective oxidation of benzene was evaluated by using a liquid-phase reaction unit, and was correlated with the surface redox property of the catalysts.
authors.forename: Dan
authors.initials: D
authors.lastname: Xu
authors.forename: Lele
authors.initials: L
authors.lastname: Liu
authors.forename: Zhenlong
authors.initials: Z
authors.lastname: Zhao
authors.forename: Lihua
authors.initials: L
authors.lastname: Jia
authors.forename: Xiangfeng
authors.initials: X
authors.lastname: Guo
authors.forename: Rui
authors.initials: R
authors.lastname: Yang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D001554:Benzene / Q000737:chemistry*; D002384:Catalysis; D006900:Hydroxylation; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D006899:Mixed Function Oxygenases / Q000737:chemistry; D008968:Molecular Conformation; D058608:Nanopores / Q000648:ultrastructure*; D010316:Particle Size; D016062:Porosity; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D017968:Vanadium Compounds / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D017968:Vanadium Compounds; C009495:titanium dioxide; D012834:Silver; C066075:vanadium pentoxide; D014025:Titanium; D006899:Mixed Function Oxygenases; D001554:Benzene