title: Directing zeolite structures into hierarchically nanoporous architectures.
abstract: Crystalline mesoporous molecular sieves have long been sought as solid acid catalysts for organic reactions involving large molecules. We synthesized a series of mesoporous molecular sieves that possess crystalline microporous walls with zeolitelike frameworks, extending the application of zeolites to the mesoporous range of 2 to 50 nanometers. Hexagonally ordered or disordered mesopores are generated by surfactant aggregates, whereas multiple cationic moieties in the surfactant head groups direct the crystallization of microporous aluminosilicate frameworks. The wall thicknesses, framework topologies, and mesopore sizes can be controlled with different surfactants. The molecular sieves are highly active as catalysts for various acid-catalyzed reactions of bulky molecular substrates, compared with conventional zeolites and ordered mesoporous amorphous materials.
authors.affiliation: Center for Functional Nanomaterials, Department of Chemistry, KAIST, Daejeon 305-701, Korea.
authors.forename: Kyungsu
authors.initials: K
authors.lastname: Na
authors.forename: Changbum
authors.initials: C
authors.lastname: Jo
authors.forename: Jeongnam
authors.initials: J
authors.lastname: Kim
authors.forename: Kanghee
authors.initials: K
authors.lastname: Cho
authors.forename: Jinhwan
authors.initials: J
authors.lastname: Jung
authors.forename: Yongbeom
authors.initials: Y
authors.lastname: Seo
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Messinger
authors.forename: Bradley F
authors.initials: BF
authors.lastname: Chmelka
authors.forename: Ryong
authors.initials: R
authors.lastname: Ryoo