title: An Adsorbate Discriminatory Gate Effect in a Flexible Porous Coordination Polymer for Selective Adsorption of CO2 over C2H2.
abstract: The adsorptive separation of C2H2 and CO2 via porous materials is nontrivial due to the close similarities of their boiling points and kinetic diameters. In this work, we describe a new flexible porous coordination polymer (PCP) [Mn(bdc)(dpe)] (H2bdc = 1,4-benzenedicarboxylic acid, dpe = 1,2-di(4-pyridyl)ethylene) having zero-dimensional pores, which shows an adsorbate discriminatory gate effect. The compound shows gate opening type abrupt adsorption for C2H2 but not for CO2, leading to an appreciable selective adsorption of CO2 over C2H2 at near ambient temperature (273 K). The origin of this unique selectivity, as unveiled by in situ adsorption-X-ray diffraction experiments and density functional theory calculations, is due to vastly different orientations between the phenylene ring of bdc and each gas in the nanopores. The structural change by photochemical transformation of this PCP via [2 + 2] photodimerization leads to the removal of inverse CO2/C2H2 selectivity, verifying the mechanism of the guest discriminatory gate effect.
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Maw Lin
authors.initials: ML
authors.lastname: Foo
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.|Department of Applied Chemistry, Graduate School of Engineering, Nagoya University , Chikusa-ku, Nagoya 464-8603, Japan.|Japan Science and Technology Agency (JST), PRESTO , 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.|RIKEN SPring-8 center , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Matsuda
authors.affiliation: Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University , Chikusa-ku, Nagoya 464-8602, Japan.
authors.forename: Yuh
authors.initials: Y
authors.lastname: Hijikata
authors.affiliation: Van 't Hoff Institute for Molecular Sciences, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: Rajamani
authors.initials: R
authors.lastname: Krishna
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sato
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura , Nishikyo-ku, Kyoto 615-8510, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Horike
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.|RIKEN SPring-8 center , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hori
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Jingui
authors.initials: J
authors.lastname: Duan
authors.affiliation: RIKEN SPring-8 center , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.|Department of Physical Science, Graduate School of Science, Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Sato
authors.affiliation: RIKEN SPring-8 center , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.|Department of Physical Science, Graduate School of Science, Osaka Prefecture University , 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Kubota
authors.affiliation: RIKEN SPring-8 center , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.|Institute of Multidisciplinary Research for Advanced Materials, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Takata
authors.affiliation: Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University , Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.|RIKEN SPring-8 center , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.|Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura , Nishikyo-ku, Kyoto 615-8510, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Kitagawa