Researchers from around the globe have triumphantly studied and comprehended the formation of fullerenes, leveraging the Swiss SLS synchrotron light source at PSI.
The possibility of fullerene and its derivatives naturally occurring in the cosmos has been a topic of speculation for a long while. These substantial carbon compounds exhibit forms similar to a soccer ball, a salad bowl, or a nanotube. Through the Swiss SLS synchrotron light source at PSI, a global team of researchers has deciphered the reaction behind their formation. The team’s discoveries were recently published in the scientific journal Nature Communications.
The lyric “We are stardust, we are golden. We are billion-year-old carbon” from the song performed by Crosby, Stills, Nash & Young at Woodstock, summarises the essential constitution of humans: stardust.
It’s common knowledge amongst anyone familiar with astronomy that both planets and humans are essentially composed of burnt-out supernovae dust and billion-year-old carbon compounds. The universe acts as a colossal reactor and comprehending these reactions is key to understanding the universe’s origins, evolution, and our own existence.
Historically, how fullerenes and their derivatives form in the cosmos has been a mystery. These carbon molecules, resembling a football, bowl, or tiny tube, were first created in a laboratory in the 1980s. In 2010, the Spitzer infrared space telescope discovered C60 molecules, known as buckyballs, which have the characteristic soccer ball shape, in the planetary nebula Tc 1. These are the largest molecules known to exist beyond our solar system.
The puzzle of their formation in the universe has been solved by a research team from Honolulu, Miami, and Tianjin, with the assistance of PSI and the vacuum ultraviolet (VUV) beamline of the Swiss SLS synchrotron light source. “We chose to collaborate with Patrick Hemberger at PSI due to its unique experimental facilities,” explains Ralf Kaiser from the University of Hawaii, a leading figure in this research.
Patrick Hemberger, a PSI scientist, has constructed a mini reactor to observe fullerene formation in real-time. A corannulene radical (C20H9) is produced in the reactor at 1,000 degrees Celsius. This molecule resembles a salad bowl and is extremely reactive. It reacts with vinyl acetylene (C4H4), adding a carbon layer to the rim of the bowl.
“Repeatedly performing this process would lead to the growth of the molecule into a nanotube end cap, as demonstrated in our computer simulations,” elucidates Alexander Mebel, a Chemistry Professor at Florida International University and co-author of the study.
However, proving this reaction was physically feasible was not the only objective, Kaiser points out. The reaction produces various isomers – molecules with the same mass but slightly differing structures. Traditional mass spectrometry makes these variants indistinguishable, but the team used photoelectron photoion coincidence spectroscopy to distinguish them. “This technique enables inferences about each individual isomer based on the structure of the measurement curve,” clarifies Hemberger.
Cracking the code of football-shaped molecules
“Though the universe houses an intricate web of molecules and chemical reactions, not all of them can be uniquely identified from telescope signals,” says Kaiser. Modelling suggests that both corannulene and vinylacetylene are present in the universe. This study confirms these molecules serve as the foundation for fullerene. “This is why our experiment at PSI is so precious to us.”
Despite the successful publication in Nature Communications, the researchers aim to perform further experiments to understand how the iconic buckyballs and fullerene molecules with 60 carbon atoms, along with the minuscule nanotubes housing even more atoms, form in the universe.
Reference: “Gas phase synthesis of the C40 nano bowl C40H10” by Lotefa B. Tuli, Shane J. Goettl, Andrew M. Turner, A. Hasan Howlader, Patrick Hemberger, Stanislaw F. Wnuk, Tianjian Guo, Alexander M. Mebel and Ralf I. Kaiser, 18 March 2023, Nature Communications.
Frequently Asked Questions (FAQs) about Fullerene Formation
What are fullerenes?
Fullerenes are large carbon molecules that occur in shapes resembling a soccer ball, a salad bowl, or a nanotube. These compounds were first created in the lab in the 1980s, and in 2010, they were discovered in the universe beyond our solar system.
How were the researchers able to study the formation of fullerenes?
The international research team used the Swiss SLS synchrotron light source at PSI to observe and understand how fullerenes form. This was possible thanks to a mini reactor built by PSI scientist Patrick Hemberger.
What are the implications of this research?
This research helps in understanding the reactions and processes that occur in the universe, aiding in our understanding of the universe’s origins, evolution, and our own existence. The study also confirmed that the molecules corannulene and vinylacetylene form the building blocks for fullerene in the universe.
What technique did the researchers use to distinguish between different isomers?
The researchers used a technique called photoelectron photoion coincidence spectroscopy. Unlike traditional mass spectrometry, this method allows conclusions to be drawn about each individual isomer based on the structure of the measurement curve.
What are the future plans for this research?
The successful publication in Nature Communications is not the end of the research. The team plans to conduct more experiments to understand how iconic buckyballs, football-shaped fullerene molecules with 60 carbon atoms, and nanotubes with even more atoms form in the universe.
More about Fullerene Formation
- Understanding Fullerenes
- The Swiss SLS Synchrotron Light Source at PSI
- The Discovery of Buckyballs
- Photoelectron Photoion Coincidence Spectroscopy
- Original study in Nature Communications