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A new form of carbon has been discovered by a team of researchers, including UF Assistant Professor of Chemistry Austin M. Evans. This innovation charts a clear path to the design of new carbon materials with potential applications in electronics, aerospace, automotive and defense industries. The team’s findings, published in the leading scientific journal Nature, will allow scientists to create on-demand carbon nanomaterials that address technological shortcomings through molecular design.

Austin M. Evans
Austin M. Evans, PhD. Photo by Anu Mayer.

Carbon naturally exists in a variety of structured forms, called allotropes. The most common occurring allotropes of carbon are diamond and graphite. Diamond, unmatched in durability and thermal conductivity, is ideal for a whole host of technological uses. On the other end of the spectrum, graphite’s material softness makes it an extremely effective conductor — and the key ingredient in lithium-ion batteries. Graphene, a relative nanomaterial newcomer discovered in the early 2000s, is an ultra-thin sheet of carbon already making waves across the chemical industry for its fire-resistant and electricity-conducting properties. All of these allotropes, despite their respective strengths, have one limiting factor in common: Their dimensional structures are rigid and cannot be easily modified.

“Generally, these allotropes have a specific dimensionality — for instance, diamonds are 3D, graphene is 2D, and carbon nanotubes are 1D,” Evans said.

The new form of carbon presented by Evans and a team of researchers breaks the rules. The researchers introduce graphullerene, a polymer that evades a clearly defined dimensionality. Graphullerene is a two-dimensional carbon sheet constructed from zero-dimensional carbon superatoms known as fullerenes.

“This is exciting because it suggests that we can now make an endless number of carbon forms that have intermixed dimensionality,” Evans said.

And, just as notable, the new material demonstrates an unusual combination of properties: Unlike other carbon-based materials, graphullerene is thermally conductive but electronically insulating.

“This combination of properties could be useful for thermal management in circuits, which is a major hurdle for the continued miniaturization of electronic devices,” Evans noted. “The pristine nature of these layers could also make them important in emerging quantum devices, which will also require unique combinations of properties not accessible in naturally occurring carbon nanomaterials.”

The research team comprised 25 scientists from nationwide institutions, including Columbia University, Harvard University, University of Rhode Island, University of Virginia, Barnard College, and Amherst College. The discovery would not have been possible by any single researcher, noted Evans. “I’m proud to have collaborated with this world-class group of scientists,” he said. “I believe the next generation of scientific innovation will come from diverse teams combining their complex expertise to change the world — this study is a remarkable demonstration of what can be accomplished when the right team comes together.”

By mixing different geometries of carbon, Evans and the research team have shown there’s a whole family of man-made allotropes just waiting to be chemically prepared and studied. Advancing this synthetic understanding and design will push the scientific frontiers in electronics, energy, and biotechnology.

Read the full study here.