title: TiO2 nanoparticles in mesoporous TUD-1: synthesis, characterization and photocatalytic performance in propane oxidation.
abstract: A series of TiO2-TUD-1 samples was synthesized with a variable Ti loading in the range Si/Ti = 100, 20, 2.5, and 1.6, by using a one-pot surfactant-free procedure. The materials obtained were characterized by elemental analysis; X-ray diffraction (XRD); N2 sorption measurements; high-resolution TEM (HR-TEM); 29Si NMR, UV-visible and Raman spectroscopy. As a function of increasing metal loading either isolated Ti atoms, or (above a Ti loading of approximately 2.5 wt- %) combinations of isolated Ti atoms and anatase (TiO2) nanoparticles were obtained; both were incorporated in the highly porous siliceous matrix. The photocatalytic performance of these materials was tested by studying the propane oxidation process following irradiation at lambda = 365 nm, selectively activating the anatase nanoparticles. In comparison to commercial anatase powder, TiO2 nanoparticles in TUD-1 showed high photochemical selectivity towards acetone, the sample with a Si/Ti ratio of 1.6 being the most selective. Size and confinement effects are consistent with the difference in performance of the TUD-1 materials and TiO2, limiting the number of electron transfers available for each propane molecule.
authors.affiliation: Reactor and Catalysis Engineering, DelftChemTech, Technische Universiteit Delft, Julianalaan 136, 2628 BL, Delft, The Netherlands.
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Hamdy
authors.forename: Otto
authors.initials: O
authors.lastname: Berg
authors.forename: Jacobus C
authors.initials: JC
authors.lastname: Jansen
authors.forename: Thomas
authors.initials: T
authors.lastname: Maschmeyer
authors.forename: Jacob A
authors.initials: JA
authors.lastname: Moulijn
authors.forename: Guido
authors.initials: G
authors.lastname: Mul