title: Hydrogen Storage and Selective, Reversible O2 Adsorption in a Metal-Organic Framework with Open Chromium(II) Sites.
abstract: A chromium(II)-based metal-organic framework Cr3 [(Cr4 Cl)3 (BTT)8 ]2 (Cr-BTT; BTT(3-) =1,3,5-benzenetristetrazolate), featuring coordinatively unsaturated, redox-active Cr(2+) cation sites, was synthesized and investigated for potential applications in H2 storage and O2 production. Low-pressure H2 adsorption and neutron powder diffraction experiments reveal moderately strong Cr-H2 interactions, in line with results from previously reported M-BTT frameworks. Notably, gas adsorption measurements also reveal excellent O2 /N2 selectivity with substantial O2 reversibility at room temperature, based on selective electron transfer to form Cr(III) superoxide moieties. Infrared spectroscopy and powder neutron diffraction experiments were used to confirm this mechanism of selective O2 binding.
authors.affiliation: Department of Chemistry, University of California, Berkeley, Berkeley, CA, 94720, USA.
authors.forename: Eric D
authors.identifier: 0000-0003-4843-8776
authors.initials: ED
authors.lastname: Bloch
authors.affiliation: Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1051, Sion, Switzerland.
authors.forename: Wendy L
authors.identifier: 0000-0002-8375-2341
authors.initials: WL
authors.lastname: Queen
authors.affiliation: Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Hudson
authors.affiliation: Department of Chemistry, University of California, Berkeley, Berkeley, CA, 94720, USA.
authors.forename: Jarad A
authors.initials: JA
authors.lastname: Mason
authors.affiliation: Department of Chemistry, University of California, Berkeley, Berkeley, CA, 94720, USA.
authors.forename: Dianne J
authors.initials: DJ
authors.lastname: Xiao
authors.affiliation: Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA.
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: Murray
authors.affiliation: Canadian Neutron Beam Centre, National Research Council, Chalk River Laboratories, Chalk River, Ontario, K0J 1P0, Canada.
authors.forename: Roxana
authors.initials: R
authors.lastname: Flacau
authors.affiliation: Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA.|Department of Chemical Engineering, University of Delaware, Newark, DE, 19716, USA.
authors.forename: Craig M
authors.initials: CM
authors.lastname: Brown
authors.affiliation: Department of Chemistry, University of California, Berkeley, Berkeley, CA, 94720, USA. jrlong@berkeley.edu.|Department of Chemical and Biomolecular Engineering, University of California, Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. jrlong@berkeley.edu.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Long
keywords: air separation; chromium; metal-organic frameworks; neutron diffraction; superoxides