Research Topics

1. Nanocarbon Electronics based on Well-controlled Chemical Assembly

To ralaize the high-perfomance electronic devices using nanocarbon materials, it is quite important to control pricisely their assembled and nanohybrid sturctures on a molecular scale.

By using molecular engineering approaches, we reported that a solution‐based SWCNT film fabrication using methoxycarbonyl polyallylamine for felxible TFT application and The concise synthesis of sulfur‐enriched graphene for molecular cluster battery applications.

References

[1] Matsunaga, Y.; Hirotani, J.; Omachi, H. AIP Adv. 2022, 12, 045322.

[2] Saita, E.; Iwata, M.; Shibata, Y.; Matsunaga, Y.; Suizu, R.; Awaga, K.; Hirotani, J.; Omachi, H. Front. Chem., 2022, 10, 841313.

[3] Matsumoto, K.; Ueno, K.; Hirotani, J.; Ohno, Y.; Omachi, H. Chem. Eur. J., 2020, 26, 6118.

[4] Omachi, H.; Inoue, T.; Hatao, S.; Shinohara. H.; Criado, A.; Yoshikawa, H.; Syrgiannis, Z.; Prato, M. Angew. Chem., Int. Ed., 2020, 59, 7836.

2. Separation of Semiconducting Carbon Nanotubes and Thin Film Transistor Applications

Semiconducting single-wall carbon nanotubes (s-SWCNTs) are promising materials with potential applications in thin-film transistors (TFTs). However, separation techniques are required to obtain highly enriched s-SWCNTs since conventional as-grown SWCNTs are a mixture of 70% semiconducting and 30% metallic SWCNTs.

To obtain high-purity s-SWCNTs, we developed a gradient gel filtration and a single-step aqueous two-phase extraction.Fabricated CNT-TFTs exhibited an excellent on/off ratio, carrier mobility, and on-current density.

References

[1] Matsunaga, Y.; Hirotani, J.; Ohno, Y.; Omachi, H. Appl. Phys. Express, 2021, 14, 017001.

[2] Omachi, H.; Komuro, T.; Matsumoto, K.; Nakajima, M.; Watanabe, H.; Hirotani, J.; Ohno, Y.; Shinohara. H. Appl. Phys. Express, 2019, 12, 097003.

[3] Thendie, B.; Omachi, H.; Hirotani, J.; Ohno, Y.; Miyata, Y.; Shinohara. H. Jpn. J. Appl. Phys., 2017, 56, 065102.

[4] Thendie, B.; Omachi, H.; Miyata, Y.; Shinohara. H. Jpn. J. Appl. Phys. 2017, 56, 015101.

3. Novel One-dimansional Materials Synthesis using Inner Space of Carbon Nanotubes

CNTs provide an ideal platform to create one-dimensional (1D) nanostructures. Over the past decade, we have developed a synthetic method for 1D nanostructured materials utilizing the inner spaces of CNTs, in so-called nanotemplate reactions.

Based on selective C–Br bond cleavage or hydrogen-bonding networking, we synthesized novel 1D nanomaterials such as linear-chain nanodiamonds, non-branched long polythiophenes, and armchair-type graphene nanoribbons.

References

[1] Kinno, Y.; Omachi, H.; Shinohara. H. Appl. Phys. Express, 2020, 13, 015002.

[2] Kinno, Y.; Omachi, H.: Nakanishi, Y.; Shinohara, H. Chem. Lett., 2018, 47, 1022-1025.

[3] Nakanishi, Y.; Omachi, H.; Fokina, N. A.; Schreiner, P. R.; Dahl, J. E. P.; Carlson, R. M. K.; Shinohara. H. Chem. Commun., 2018, 54, 3823-3826.

[4] Nakanishi, Y.; Omachi, H.; Fokina, N. A.; Schreiner, P. R.; Kitaura, R.; Dahl, J. E. P.; Carlson, R. M. K.; Shinohara. H. Angew. Chem., Int. Ed. 2015, 54, 10802-10806.

4. Isolation of Missing Metallofullaerens by In-situ Trifluoromethylation

Endohedral metallofullerenes, encapsulating metal atoms in the internal space of spherical carbon structures, have attracted much attention due to their unique properties. However, most of metallofullerenes have not been obtained because of their extremely high chemical reactivity.

Recently, we developed an in situ trifluoromethylation method for the extraction and purification of these missing metallofullerenes. Their X-ray crystallographic structures and photophysical/megnetic properties were also revealed.

References

[1] Xu, D.; Jiang, Y.; Wang, Y.; Zhou, T.; Shi, Z.; Omachi, H.; Shinohara. H.; Sun, B.; Wang, Z. Inorg. Chem., 2019, 58, 14325.

[2] Nakagawa, A.; Aoyagi, S.; Omachi, H.; Ishino, K.; Nishino, M.; Rio, J.; Ewels, C.; Shinohara, H. R. Soc. Open Sci., 2018, 5, 181015.

[3] Nakagawa, A.; Nishino, M.; Niwa, H.; Ishino, K.; Wang, Z.; Omachi, H.; Furukawa, K.; Yamaguchi, T.; Kato, T.; Bandow, S.; Rio, J.; Ewels, C.; Aoyagi, S.; Shinohara, H. Nature Commun., 2018, 9, 3073.

[4] Wang, Z.; Aoyagi, S.; Omachi, H.; Kitaura, R.; Shinohara. H. Angew. Chem., Int. Ed. 2016, 55, 199-202.