TY - JOUR
T1 - Confined water-mediated high proton conduction in hydrophobic channel of a synthetic nanotube
AU - Otake, Ken ichi
AU - Otsubo, Kazuya
AU - Komatsu, Tokutaro
AU - Dekura, Shun
AU - Taylor, Jared M.
AU - Ikeda, Ryuichi
AU - Sugimoto, Kunihisa
AU - Fujiwara, Akihiko
AU - Chou, Chien Pin
AU - Sakti, Aditya Wibawa
AU - Nishimura, Yoshifumi
AU - Nakai, Hiromi
AU - Kitagawa, Hiroshi
N1 - Funding Information:
This work was supported by Core Research for Evolutional Science and Technology (CREST) “Creation of Innovative Functions of Intelligent Materials on the Basis of the Element Strategy”, ACCEL from Japan Science and Technology Agency (JST), JSPS KAKENHI Grant Numbers JP20350030, JP23245012, JP15H05479, JP17H05366, JP19K05494 and JP19H04572 (Coordination Asymmetry) and MEXT Project for Developing Innovation Systems (Regional Innovation Strategy Support Program “Kyoto Next-Generation Energy System Creation Strategy”). Theoretical calculations were supported in part by the supercomputer of ACCMS, Kyoto University. Synchrotron XRD measurements were supported by the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal Nos. 2016A1343, 2016A1361, 2016B1438, 2017A1349, 2017A1366, 2017B1483, and 2018A1434).
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Water confined within one-dimensional (1D) hydrophobic nanochannels has attracted significant interest due to its unusual structure and dynamic properties. As a representative system, water-filled carbon nanotubes (CNTs) are generally studied, but direct observation of the crystal structure and proton transport is difficult for CNTs due to their poor crystallinity and high electron conduction. Here, we report the direct observation of a unique water-cluster structure and high proton conduction realized in a metal-organic nanotube, [Pt(dach)(bpy)Br]4(SO4)4·32H2O (dach: (1R, 2R)-(–)-1,2-diaminocyclohexane; bpy: 4,4’-bipyridine). In the crystalline state, a hydrogen-bonded ice nanotube composed of water tetramers and octamers is found within the hydrophobic nanochannel. Single-crystal impedance measurements along the channel direction reveal a high proton conduction of 10−2 Scm−1. Moreover, fast proton diffusion and continuous liquid-to-solid transition are confirmed using solid-state 1H-NMR measurements. Our study provides valuable insight into the structural and dynamical properties of confined water within 1D hydrophobic nanochannels.
AB - Water confined within one-dimensional (1D) hydrophobic nanochannels has attracted significant interest due to its unusual structure and dynamic properties. As a representative system, water-filled carbon nanotubes (CNTs) are generally studied, but direct observation of the crystal structure and proton transport is difficult for CNTs due to their poor crystallinity and high electron conduction. Here, we report the direct observation of a unique water-cluster structure and high proton conduction realized in a metal-organic nanotube, [Pt(dach)(bpy)Br]4(SO4)4·32H2O (dach: (1R, 2R)-(–)-1,2-diaminocyclohexane; bpy: 4,4’-bipyridine). In the crystalline state, a hydrogen-bonded ice nanotube composed of water tetramers and octamers is found within the hydrophobic nanochannel. Single-crystal impedance measurements along the channel direction reveal a high proton conduction of 10−2 Scm−1. Moreover, fast proton diffusion and continuous liquid-to-solid transition are confirmed using solid-state 1H-NMR measurements. Our study provides valuable insight into the structural and dynamical properties of confined water within 1D hydrophobic nanochannels.
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U2 - 10.1038/s41467-020-14627-z
DO - 10.1038/s41467-020-14627-z
M3 - Article
C2 - 32071299
AN - SCOPUS:85079809800
SN - 2041-1723
VL - 11
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 843
ER -