title: Partially fluorinated MIL-47 and Al-MIL-53 frameworks: influence of functionalization on sorption and breathing properties.
abstract: Two perfluorinated metal hydroxo terephthalates [M(III)(OH)(BDC-F)]·n(guests) (M(III) = V, MIL-47-F-AS or 1-AS; Al, Al-MIL-53-F-AS or 2-AS) (BDC-F = 2-fluoro-1,4-benzenedicarboxylate; AS = as-synthesized) have been synthesized by a hydrothermal method using microwave irradiation (1-AS) or conventional electric heating (2-AS), respectively. The unreacted or occluded H(2)BDC-F molecules can be removed under vacuum by direct thermal activation or exchange of guest molecules followed by thermal treatment leading to the empty-pore forms of the title compounds [V(IV)(O)(BDC-F)] (MIL-47-F, 1) and [Al(III)(OH)(BDC-F)] (Al-MIL-53-F, 2). Thermogravimetric analysis (TGA) and temperature-dependent XRPD (TDXRPD) experiments indicate that the compounds are stable up to 385 and 480 °C, respectively. Both of the thermally activated compounds exhibit significant microporosity, as verified by N(2), CO(2), n-hexane, o- and p-xylene sorption analyses. The structural changes of 2 upon adsorption of CO(2), n-hexane, o- and p-xylene were highly influenced due to functionalization by -F groups, as compared to parent Al-MIL-53. The -F groups also introduce a certain degree of hydrophobicity into the frameworks, as demonstrated by the H(2)O sorption analyses.
authors: Department of Inorganic and Physical Chemistry, Centre for Ordered Materials, Organometallics and Catalysis, Ghent University, Ghent, Belgium.
authors: Shyam
authors: S
authors: Biswas
authors: Tom
authors: T
authors: Rémy
authors: Sarah
authors: S
authors: Couck
authors: Dmytro
authors: D
authors: Denysenko
authors: Geert
authors: G
authors: Rampelberg
authors: Joeri F M
authors: JF
authors: Denayer
authors: Dirk
authors: D
authors: Volkmer
authors: Christophe
authors: C
authors: Detavernier
authors: Pascal
authors: P
authors: Van Der Voort
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D014639:Vanadium / Q000737:chemistry*; D014992:Xylenes / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D014992:Xylenes; D014639:Vanadium; D002245:Carbon Dioxide; D000535:Aluminum