The researchers synthesized the first molecular nanocarbon in the form of a strip with a twisted Möbius band topology (Möbi belt consisting only carbon atoms) – the Möbius carbon nanoband – which paved the way for the development of nanocarbon materials with a complex topological structure.
Obtaining structurally uniform nanocarbons – preferably as individual molecules – is a major challenge in nanocarbon science on how to properly combine structure and function. Therefore, the construction of structurally uniform nanocarbones is essential for the development of functional materials in nanotechnologies, electronics, optics and biomedical applications. An important tool to achieve this goal is molecular nanocarbon science, which is a bottom-up method for the production of nanocarbones using synthetic organic chemistry. However, the molecular nanocarbons synthesized (Möbi belt consisting only carbon atoms) so far have simple structures, such as a ring, a bowl or a strip. In order to identify unknown and theoretically assumed nanocarbons, it is necessary to develop new methods for the synthesis of nanocarbon molecules with a more complex structure.
Today, a team led by Kenichiro Itami (professor, Nagoya University) and Yasutomo Segawa (professor, Institute of Molecular Science) and Yuh Hijikata, (specially appointed associate professor, ICReDD) synthesize twisted molecular nanocarbon. Möbius band topology, ie. in the Möbius carbon nanoband.
“The Möbi carbon nanotube is a dream molecule of the scientific community after we announced in 2017 the first chemical synthesis of a carbon nanotube – ultra-short carbon nanotubes. Like the belts we use every day, we ask,” We asked ourselves what happened. our ‘molecular belt’ when it is twisted. “It’s still an incredibly beautiful molecule,” said Kenichiro Itami, head of the research group.
However, this turnaround is easier said than done. “We know from our previous synthesis of carbon nanobands that deformation energy is the biggest barrier to synthesis. In addition, increased torsion within the band structure increases the stress energy of the final target molecule. , Project manager.
The rational synthetic route was determined by theoretical analysis of high-voltage derivatives of the band form and the deformed molecular structure of the Möbius carbon nanopass. The Möbi carbon nanoband was synthesized in 14 chemical reaction steps, including a newly developed functionalization reaction, a Z-selective Wittig reaction sequence, and a voltage-induced nickel-mediated homocoupling reaction. Spectroscopic analysis and molecular dynamics simulations have shown that the twisted group of the Möbius belt moves rapidly around the molecule of Möbius carbon nanobalt in solution.
The topological chirality obtained from the Möbius structure was confirmed experimentally by chiral separation and circular dichroism spectroscopy. Historically, new forms of carbon and nanocarbon have constantly opened the door to new science and technology and led to the discovery of unique (and often unpredictable) properties, functions and applications. Today’s work is a revolutionary act that paves the way for the development of nanocarbon materials with complex topological structures and the birth of new materials sciences with Möbius topology.
