title: Synthesis of MIL-102, a chromium carboxylate metal-organic framework, with gas sorption analysis.
abstract: A new three-dimensional chromium(III) naphthalene tetracarboxylate, CrIII3O(H2O)2F{C10H4(CO2)4}1.5.6H2O (MIL-102), has been synthesized under hydrothermal conditions from an aqueous mixture of Cr(NO3)3.9H2O, naphthalene-1,4,5,8-tetracarboxylic acid, and HF. Its structure, solved ab initio from X-ray powder diffraction data, is built up from the connection of trimers of trivalent chromium octahedra and tetracarboxylate moieties. This creates a three-dimensional structure with an array of small one-dimensional channels filled with free water molecules, which interact through hydrogen bonds with terminal water molecules and oxygen atoms from the carboxylates. Thermogravimetric analysis and X-ray thermodiffractometry indicate that MIL-102 is stable up to approximately 300 degrees C and shows zeolitic behavior. Due to topological frustration effects, MIL-102 remains paramagnetic down to 5 K. Finally, MIL-102 exhibits a hydrogen storage capacity of approximately 1.0 wt % at 77 K when loaded at 3.5 MPa (35 bar). The hydrogen uptake is discussed in relation with the structural characteristics and the molecular simulation results. The adsorption behavior of MIL-102 at 304 K resembles that of small-pore zeolites, such as silicalite. Indeed, the isotherms of CO2, CH4, and N2 show a maximum uptake at 0.5 MPa, with no further significant adsorption up to 3 MPa. Crystal data for MIL-102: hexagonal space group P(-)6 (No. 169), a = 12.632(1) A, c = 9.622(1) A.
authors.affiliation: Institut Lavoisier Versailles, UMR 8180, CNRS, Université de Versailles St-Quentin-en-Yvelines, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France.
authors.forename: Suzy
authors.initials: S
authors.lastname: Surblé
authors.forename: Franck
authors.initials: F
authors.lastname: Millange
authors.forename: Christian
authors.initials: C
authors.lastname: Serre
authors.forename: Tina
authors.initials: T
authors.lastname: Düren
authors.forename: Michel
authors.initials: M
authors.lastname: Latroche
authors.forename: Sandrine
authors.initials: S
authors.lastname: Bourrelly
authors.forename: Philip L
authors.initials: PL
authors.lastname: Llewellyn
authors.forename: Gérard
authors.initials: G
authors.lastname: Férey