Rolling two-dimensional covalent organic framework (COF) sheets into one-dimensional electronic and proton-conductive nanotubes
Mimicking the interconvertible carbon allotropes of 2-dimensional (2D) graphene and 1-dimensional (1D) carbon nanotubes (CNTs), herein we report the in situ transformation of 2D π-conjugated covalent organic frameworks (COFs) sheet into 1D nanotubular structures via self-assembly the sheets at solvent interfaces. The facile "roll-sheets" self-assembly resulted in coaxial nanotubes with uniform cross-sectional diameter, which was realized for diazapyrene-based COFs but not for the corresponding pyrene COF, although both possess similar chemical structures. Upon replacing the carbon atoms at 2,7-positions of pyrene with nitrogen, contrasting optical and electronic properties were realized, reflecting the rolled structure of the conjugated 2D sheets. The nanotubes exhibited concerted electronic- and proton-conducting nature with stable conducting pathways at ambient conditions. The nitrogen centers act simultaneously as the site for charge carrier doping and proton acceptors, as evidenced by the high photo- and electrical conductivity, as well as the record proton conductivity (σ = 1.98 S cm<sup>-1</sup>) results. The present diazapyrene-based 1D nanotubular COF serves as a unique materials platform with electronic conduction in the wall and proton conduction in the core, respectively.
Authors
- Masayuki Suda (ORCID: https://orcid.org/0000-0003-0869-2366)
- Z. Q. Li (ORCID: https://orcid.org/0000-0001-5613-716X)
- Rajendra Prasad Paitandi (ORCID: https://orcid.org/0000-0002-8349-8494)
- Yusuke Tsutsui (ORCID: https://orcid.org/0000-0002-3138-5009)
- Takayuki Tanaka (ORCID: https://orcid.org/0000-0001-8018-7984)
- Masaki Nobuoka (ORCID: https://orcid.org/0009-0000-8806-6968)
- Yoshihiro Miyake (ORCID: https://orcid.org/0000-0003-0247-531X)
- Wakana Matsuda
- Bin Chen (ORCID: https://orcid.org/0000-0003-0372-7566)
- Hiroshi Shinokubo (ORCID: https://orcid.org/0000-0002-5321-2205)
- Shu Seki (ORCID: https://orcid.org/0000-0001-7851-4405)
- Hironori Kaji (ORCID: https://orcid.org/0000-0002-5111-3852)
- Samrat Ghosh (ORCID: https://orcid.org/0000-0002-5946-3013)
- Hiroshi Kageyama (ORCID: https://orcid.org/0000-0002-3911-9864)
- Tomomi Shimazaki (ORCID: https://orcid.org/0000-0003-4469-1651)
- Masanori Tachikawa (ORCID: https://orcid.org/0000-0002-5489-5714)
- Takahiro Ezaki (ORCID: https://orcid.org/0000-0003-4175-3028)
- Makito Takagi (ORCID: https://orcid.org/0000-0001-5767-7942)
- Tong Zhu (ORCID: https://orcid.org/0000-0003-0288-0462)
- Yasunobu Ando
- Katsuaki Suzuki
Institutions
- Kyoto University (JP)
- Innovative Research (United States) (US)
- Instituto de Investigaciones Químicas (ES)
- Kyoto University Institute for Chemical Research
- Institute of Science Tokyo (JP)
- Nagoya University (JP)
- The University of Tokyo (JP)
- Yokohama City University (JP)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2025-04-16
- DOI
- https://doi.org/10.1073/pnas.2424314122
- Citations
- 3
- Primary Topic
- Covalent Organic Framework Applications
- Type
- article
- Field-Weighted Citation Impact
- 1.55
Funders
- Japan Society for the Promotion of Science
- Core Research for Evolutional Science and Technology