title: A Series of Layered Assemblies of Hydrogen-Bonded, Hexagonal Networks of C3-Symmetric π-Conjugated Molecules: A Potential Motif of Porous Organic Materials.
abstract: Hydrogen-bonded porous organic crystals are promising candidates for functional organic materials due to their easy construction and flexibility arising from reversible bond formation-dissociation. However, it still remains challenging to form porous materials with void spaces that are well-controlled in size, shape, and multiplicity because even well-designed porous frameworks often fail to generate pores within the crystal due to unexpected disruption of hydrogen bonding networks or interpenetration of the frameworks. Herein, we demonstrate that a series of C3-symmetric π-conjugated planar molecules (Tp, T12, T18, and Ex) with three 4,4'-dicarboxy-o-terphenyl moieties in their periphery can form robust hydrogen-bonded hexagonal networks (H-HexNets) with dual or triple pores and that the H-HexNets stack without interpenetration to yield a layered assembly of H-HexNet (LA-H-HexNet) with accessible volumes up to 59%. Specifically, LA-H-HexNets of Tp and T12 exhibit high crystallinity and permanent porosity after desolvation (activation): SABET = 788 and 557 m(2) g(-1), respectively, based on CO2 sorption at 195 K. We believe that the present design principle can be applied to construct a wide range of two-dimensional noncovalent organic frameworks (2D-nCOFs) and create a pathway to the development of a new class of highly porous functional materials.
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hisaki
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Shoichi
authors.initials: S
authors.lastname: Nakagawa
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Ikenaka
authors.affiliation: Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University , 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imamura
authors.affiliation: RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Katouda
authors.affiliation: RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047, Japan.
authors.forename: Motomichi
authors.initials: M
authors.lastname: Tashiro
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University , Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Hiromu
authors.initials: H
authors.lastname: Tsuchida
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University , Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Tomoki
authors.initials: T
authors.lastname: Ogoshi
authors.affiliation: Rigaku Corporation , Matsubara-cho 3-9-12, Akishima, Tokyo 196-8666, Japan.
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Sato
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University , 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Norimitsu
authors.initials: N
authors.lastname: Tohnai
authors.affiliation: The Institute of Scientific and Industrial Research, Osaka University , 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors.forename: Mikiji
authors.initials: M
authors.lastname: Miyata