BC Chemistry Professors Find New Form of Synthetic Carbon
Published: Sunday, September 29, 2013
Updated: Sunday, September 29, 2013 19:09
Members of the Boston College chemistry department, along with faculty and researchers from Japan’s Nagoya University, recently synthesized a new form of carbon and published their work in the September edition of the Nature Chemistry scientific journal.
“Carbon exists in two different forms in nature,” said assistant chairperson of the BC chemistry department Lawrence Scott, one of the five co-authors of the work. “In pure form, it exists as graphite, which is pencil lead—that’s just pure carbon—or as diamonds, which is also pure carbon.”
In order to construct a new, synthetic carbon structure, the group altered the physical makeup of the carbon molecule. “It’s known that the carbon atoms in the graphite are all connected together, so each carbon atom is connected to three other carbon atoms, which are connected to three others and so on. They exist as a big sheet of carbon atoms that looks like a honeycomb,” Scott said. “All the carbon atoms are joined in hexagonal rings in this way, and at every corner there’s a carbon atom.”
“What we’ve made is like graphite, so every carbon is bonded to three other carbons in the same way, but instead of having all six-membered rings of carbons, some of the rings have only five sides, so pentagons, and some have seven sides,” he said. “These odd-membered rings change the properties of the graphite completely. One thing they do is to make it no longer a two-dimensional planar sheet, but actually cause it to warp. The new molecule that we’ve made has 80 carbon atoms all stuck together this way.”
As a result, this new molecule boasts properties—such as its ability to oxidize and reduce and its solubility—different from those of natural carbon. These different properties allow for new applications, as Scott said, in the context of materials sciences. “Material sciences, broadly speaking, is that area of human activity involved with the development of new materials and their new properties,” he said. “Our specialty is synthesizing compounds and coming up with new methods for synthesizing compounds—designing and making new compounds, showing what can be done, extending the range of what used to be possible to what is now possible.
“We’ve measured its properties and have shown that they’re different from what you get with previously known forms of carbon,” Scott said. “This is of interest to people who use carbon and other materials for various applications—for example, carbon is used in batteries, new forms of carbon are being used for making ultra-small transistors and other electronics and microelectronics, and by showing that you can make related but different forms of carbon, it expands the possibilities for what engineers can design and synthesize.”
In addition to Scott, the research team included Qianyan Zhang, a Peking University postdoctoral researcher who recently returned to China after a two-year fellowship working in Merkert Chemistry Center under Scott; Kenichiro Itami, a Nagoya University chemistry professor; Katsuaki Kawasumi, a graduate student under Itami who had come to BC on a fellowship to perform research for his doctoral thesis; and Yasutomo Segawa, an assistant professor at Nagoya.
Being published in Nature Chemistry and especially having the article featured on the journal’s cover proved a great honor for the researchers. “Nature Chemistry is a very prestigious journal,” Scott said. “They publish very few papers and they’re very rigorous about which ones they accept and which ones they reject, so we’re very happy to be in it.”
“We’re especially proud of this particular issue because, of the 10 papers in this issue, two of the other papers are also from Boston College,” he said.
Scott hopes that this breakthrough is only the beginning of the development of synthetic carbon. “There’s actually a second student from Japan who is here working in my lab right now, he came this summer on a similar fellowship and he’s working on trying to make another one of these compounds,” he said.
“Professor Itami and I are continuing to collaborate in this area, not just for this particular form of carbon, but we think now that we can make other highly contorted forms of carbon that have other properties. So this is a sort of beginning, opening up a new area of chemistry where we can make networks of carbon atoms like this that have five, six, seven carbon atoms in different arrangements, and each different arrangement will have its own different properties.”