Trapping Atoms: The Creation of One-Dimensional Gas Inside Carbon Nanotubes

Tuesday - January 23 2024, 13:32 UTC - 10 months ago

Scientists at the University of Nottingham's School of Chemistry have trapped individual atoms of krypton inside carbon nanotubes using advanced transmission electron microscopy techniques. This allows for the accurate observation and study of atoms at the single-atom level. The use of Buckminster fullerenes helps in transporting individual atoms into the nano test tubes, leading to the creation of a one-dimensional gas in a solid material. This breakthrough opens up new possibilities for studying materials and understanding the fundamental nature of atoms.

Scientists at the University of Nottingham's School of Chemistry have successfully trapped individual atoms of krypton, a noble gas, inside a carbon nanotube, creating a one-dimensional gas. This research utilized advanced transmission electron microscopy (TEM) methods and marks a significant leap in our ability to observe and understand the behavior of atoms at the single-atom level.

Traditional spectroscopy methods have limitations in directly observing individual atoms in action, making it challenging for scientists to study their real-time behavior. However, the use of carbon nanotubes, which act as "nano test tubes," allows researchers to entrap and accurately position atoms, offering a unique glimpse into their dynamic movements.

Professor Andrei Khlobystov from the University of Nottingham explained in a press release, "Carbon nanotubes enable us to entrap atoms and accurately position and study them at the single-atom level in real-time. For instance, we successfully trapped noble gas krypton (Kr) atoms in this study. Because Kr has a high atomic number, it is easier to observe in a TEM than lighter elements. This allowed us to track the positions of Kr atoms as moving dots." .

The team utilized state-of-the-art transmission electron microscopy (TEM) techniques, specifically the SALVE TEM, to witness the process of krypton atoms joining together to form pairs. These pairs, held together by the van der Waals interaction, represent a significant breakthrough in the field of chemistry and physics. Professor Ute Kaiser, former head of the Electron Microscopy of Materials Science group, highlighted the importance of this innovation, stating, "It allows us to see the van der Waals distance between two atoms in real space." .

To transport individual krypton atoms into the nano test tubes, the researchers used Buckminster fullerenes, which are football-shaped molecules consisting of 60 carbon atoms. These molecules were crucial in improving the precision of the experiments. Ian Cardillo-Zallo, a PhD student at the University of Nottingham, explained, "Krypton atoms can be released from the fullerene cavities by fusing the carbon cages. This can be achieved by heating at 1200°C or irradiating with an electron beam." .

The team successfully observed krypton atoms exiting fullerene cages to form a one-dimensional gas. Once freed from their carrier molecules, these atoms were confined to move in one dimension along the nanotube channel due to the extremely narrow space. This unique confinement caused the atoms to slow down, akin to vehicles in traffic congestion.

"As far as we know, this is the first time that chains of noble gas atoms have been imaged directly, leading to the creation of a one-dimensional gas in a solid material," said Professor Paul Brown, director of the Nanoscale and Microscale Research Centre at the University of Nottingham.

The team's future plans include using electron microscopy to image temperature-controlled phase transitions and chemical reactions in one-dimensional systems, unlocking new possibilities for studying materials and further understanding the fundamental nature of atoms.