title: A New Synthetic Route to Microporous Silica with Well-Defined Pores by Replication of a Metal-Organic Framework.
abstract: Microporous amorphous hydrophobic silica materials with well-defined pores were synthesized by replication of the metal-organic framework (MOF) [Cu3 (1,3,5-benzenetricarboxylate)2 ] (HKUST-1). The silica replicas were obtained by using tetramethoxysilane or tetraethoxysilane as silica precursors and have a micro-meso binary pore system. The BET surface area, the micropore volume, and the mesopore volume of the silica replica, obtained by means of hydrothermal treatment at 423 K with tetraethoxysilane, are 620 m(2) g(-1) , 0.18 mL g(-1) , and 0.55 mL g(-1) , respectively. Interestingly, the silica has micropores with a pore size of 0.55 nm that corresponds to the pore-wall thickness of the template MOF. The silica replica is hydrophobic, as confirmed by adsorption analyses, although the replica has a certain amount of silanol groups. This hydrophobicity is due to the unique condensation environment of the silica precursors in the template MOF.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan), Fax: (+81) 42-388-7040. kondoa@cc.tuat.ac.jp.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kondo
authors.affiliation: Department of Chemistry, The Pennsylvania State University, 104 Chemistry Building, University Park, PA 16802 (USA).
authors.forename: Anthony Shoji
authors.initials: AS
authors.lastname: Hall
authors.affiliation: Department of Chemistry, The Pennsylvania State University, 104 Chemistry Building, University Park, PA 16802 (USA).
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Mallouk
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan), Fax: (+81) 42-388-7040.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Maeda
keywords: adsorption; hydrophobic effect; metal-organic frameworks; microporous materials; silica