title: Facile synthesis of ultrasmall monodisperse "raisin-bun"-type MoO3/SiO2 nanocomposites with enhanced catalytic properties.
abstract: We report the preparation of ultrasmall monodisperse MoO3/SiO2 nanocomposites in reverse microemulsions formed by Brij-58/cyclohexane/water. The nanocomposites are of "raisin-bun"-type with 1.0 ± 0.2 nm MoO3 homogeneously dispersed in 23 ± 2 nm silica spheres. Characterization is carried out based on transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectrometry (EDS), X-ray powder diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma-optical emission spectrometry (ICP-OES), N2 sorption measurement, and NH3 temperature-programmed desorption (NH3-TPD). The as-prepared MoO3/SiO2 nanocomposites are microporous and exhibit enhanced catalytic activities for acetalization of benzaldehyde with ethylene glycol and can be repeatedly used 5 times without obvious deactivation. The catalytic performance improvement is attributed to the unique structure and ultrasmall size of the nanocomposites.
authors.affiliation: State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, China.
authors.forename: Jiasheng
authors.initials: J
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Shufen
authors.initials: S
authors.lastname: Zhang
authors.forename: Rongwen
authors.initials: R
authors.lastname: Lu
mesh_terms: D001547:Benzaldehydes / Q000737:chemistry; D002384:Catalysis; D002592:Cetomacrogol / Q000737:chemistry; D003510:Cyclohexanes / Q000737:chemistry; D004655:Emulsions / Q000737:chemistry; D019855:Ethylene Glycol / Q000737:chemistry; D008982:Molybdenum / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D001547:Benzaldehydes; D003510:Cyclohexanes; D004655:Emulsions; D010087:Oxides; D014867:Water; C082290:molybdenum trioxide; C506365:Cyclohexane; D012822:Silicon Dioxide; D008982:Molybdenum; D002592:Cetomacrogol; D019855:Ethylene Glycol; C032175:benzaldehyde