title: Solvent evaporation induced aggregating assembly approach to three-dimensional ordered mesoporous silica with ultralarge accessible mesopores.
abstract: A solvent evaporation induced aggregating assembly (EIAA) method has been demonstrated for synthesis of highly ordered mesoporous silicas (OMS) in the acidic tetrahydrofuran (THF)/H(2)O mixture by using poly(ethylene oxide)-b-poly(methyl methacrylate) (PEO-b-PMMA) as the template and tetraethylorthosilicate (TEOS) as the silica precursor. During the continuous evaporation of THF (a good solvent for PEO-b-PMMA) from the reaction solution, the template molecules, together with silicate oligomers, were driven to form composite micelles in the homogeneous solution and further assemble into large particles with ordered mesostructure. The obtained ordered mesoporous silicas possess a unique crystal-like morphology with a face centered cubic (fcc) mesostructure, large pore size up to 37.0 nm, large window size (8.7 nm), high BET surface area (508 m(2)/g), and large pore volume (1.46 cm(3)/g). Because of the large accessible mesopores, uniform gold nanoparticles (ca. 4.0 nm) can be introduced into mesopores of the OMS materials using the in situ reduction method. The obtained Au/OMS materials were successfully applied to fast catalytic reduction of 4-nitrophenol in the presence of NaHB(4) as the reductant. The supported catalysts can be reused for catalytic reactions without significant decrease in catalysis performance even after 10 cycles.
authors: Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Advanced Materials Lab, Fudan University, Shanghai 200433, China.
authors: Jing
authors: J
authors: Wei
authors: Hai
authors: H
authors: Wang
authors: Yonghui
authors: Y
authors: Deng
authors: Zhenkun
authors: Z
authors: Sun
authors: Lin
authors: L
authors: Shi
authors: Bo
authors: B
authors: Tu
authors: Mohammad
authors: M
authors: Luqman
authors: Dongyuan
authors: D
authors: Zhao
mesh_terms: D002384:Catalysis; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D011108:Polymers / Q000737:chemistry*; D012542:Scattering, Radiation; D012822:Silicon Dioxide / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*
chemical_list: D011108:Polymers; D012997:Solvents; D012822:Silicon Dioxide