title: Confinement of single polysilane chains in coordination nanospaces.
abstract: Understanding the intrinsic properties of single conducting polymer chains is of interest, largely for their applications in molecular devices. In this study, we report the accommodation of single polysilane chains with hole-transporting ability in porous coordination polymers (PCPs), [Al(OH)(L)]n (1a; L = 2,6-naphthalenedicarboxylate, channel size = 8.5 × 8.5 Å(2), 1b; L = 4,4'-biphenyldicarboxylate, channel size = 11.1 × 11.1 Å(2)). Interestingly, the isolation of single polysilane chains increased the values of carrier mobility in comparison with that in the bulk state due to the elimination of the slow interchain hole hopping. Moreover, even when the chains are isolated one another, the main chain conformation of polysilane could be controlled by changing the pore environment of PCPs, as evidenced by Raman spectroscopy, solid-state NMR measurements, and molecular dynamics simulation. Hence, we succeeded in varying the conducting property of single polysilane chains. Additionally, polysilanes have a drawback, photodegradation under ultraviolet light, which should be overcome for the application of polysilanes. It is noteworthy that the accommodation of polysilane in the nanopores did not exhibit photodegradation. These results highlight that PCP-polysilane hybrids are promising candidates for further use in the field of molecular electronics.
authors.affiliation: †Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitao
authors.affiliation: ‡Department of Materials Science, University of Milano Bicocca, Via R. Cozzi 55, 20125 Milan, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Bracco
authors.affiliation: ‡Department of Materials Science, University of Milano Bicocca, Via R. Cozzi 55, 20125 Milan, Italy.
authors.forename: Angiolina
authors.initials: A
authors.lastname: Comotti
authors.affiliation: ‡Department of Materials Science, University of Milano Bicocca, Via R. Cozzi 55, 20125 Milan, Italy.
authors.forename: Piero
authors.initials: P
authors.lastname: Sozzani
authors.affiliation: §National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-044, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Naito
authors.affiliation: ∥Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Shu
authors.initials: S
authors.lastname: Seki
authors.affiliation: †Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.|⊥CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Uemura
authors.affiliation: †Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.|#Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Kitagawa