Researchers have made a groundbreaking advancement in producing carbon nanotubes, often referred to as the ‘king of nanomaterials.’
A team of researchers has progressed significantly in the production of carbon nanotubes (CNTs) by creating a new catalyst that enables precise control of their atomic structure, specifically their chirality. This development opens up new possibilities for innovative semiconductor technologies, resolving a challenge that has persisted for more than three decades.
The research team, led by Associate Professor Toshiaki Kato from the Advanced Institute for Materials Research (WPI-AIMR) and including scientists from across Japan, has successfully produced CNTs with a chiral index of (6,5) at an exceptional purity level exceeding 95%.
This research was published in ACS Nano on August 20, 2024.
“A carbon nanotube is essentially a layer of carbon rolled into a tube shape,” explains Kato. “While this may sound straightforward, CNTs are highly valued due to their remarkable conductivity, optical properties, and mechanical strength.”
It’s easy to see why they are referred to as the “king of nanomaterials.” Their extensive range of beneficial characteristics makes them suitable for numerous applications, from building aircraft and spacecraft to advancing medical technology.
“The challenge of controlling CNT chirality has hindered their use in industry, which is why we embarked on this project to find a catalyst that could reliably produce the desired results,” Kato points out. Up until now, single-chirality synthesis with over 90% purity has only been accomplished for (14,4) and (12,6) chiralities.
By introducing a new catalyst made up of nickel (Ni), tin (Sn), and iron (Fe), the researchers have found a new route for chirality-controlled synthesis. This NiSnFe catalyst serves as a highly specialized growth promoter, enabling the selective production of (6,5) chirality CNTs. In addition, these chirality-pure bundle structures of (6,5) CNTs demonstrate more than a 20-fold increase in their photoluminescence lifetime when compared to isolated (6,5) CNTs. This method could potentially be applied in the future to achieve other chiralities.
The research team is hopeful that their discoveries will drive considerable advancements in the manufacturing and application of semiconductor devices.
