Published on July 19th, 2013 | by James Ayre0
New Form Of Carbon Created — “Grossly Warped Nanographene”
July 19th, 2013 by James Ayre
An entirely new form of carbon — “grossly warped nanographene” — has been created by researchers at Boston College and Nagoya University in Japan. The grossly warped nanographene is the first new form of carbon synthesized in quite some time.
The new material is actually composed of multiple identical pieces of grossly warped graphene which are joined together in a network of 26 rings, with 30 hydrogen atoms encircling them — the 26 rings are created out of exactly 80 carbon atoms. As they each measure slightly more than a nanometer across, each individual molecule is referred to as a “nanocarbon,” or specifically in this case, a “grossly warped nanographene.”
Until as recently as 1985, it was thought that there were likely only two stable forms of pure carbon — diamond and graphite. But then fullerenes were discovered — which are essentially just hollow balls of pure carbon. After that somewhat surprising discovery, research on the subject intensified, and now, as a result, various other forms of pure carbon have been discovered; including carbon nanotubes (long, ultra-thin hollow tubes of pure carbon) and graphene (large flat sheets of pure carbon one-atom thick). This new discovery follows in that tradition of research.
There’s something else to note about the new material: as a result of the “distorted” shape, the optical, physical, and electronic properties of the material are different from those of “normal” graphene. Among the most interesting differences to note is that the new form is considerably more soluble than planar graphene, no doubt a difference that could prove useful for some applications.
The press release from Boston College provides details on the new material:
Graphene sheets prefer planar, 2-dimensional geometries as a consequence of the hexagonal, chicken wire-like, arrangements of trigonal carbon atoms comprising their two-dimensional networks. The new form of carbon, however, is wildly distorted from planarity as a consequence of the presence of five 7-membered rings and one 5-membered ring embedded in the hexagonal lattice of carbon atoms.
Odd-membered-ring defects such as these not only distort the sheets of atoms away from planarity, they also alter the physical, optical, and electronic properties of the material, according to one of the principle authors, Lawrence T. Scott, the Jim and Louise Vanderslice and Family Professor of Chemistry at Boston College.
Graphene has been highly touted as a revolutionary material for nanoscale electronics. By introducing multiple odd-membered ring defects into the graphene lattice, Scott and his collaborators have experimentally demonstrated that the electronic properties of graphene can be modified in a predictable manner through precisely controlled chemical synthesis.
“Our new grossly warped nanographene is dramatically more soluble than a planar nanographene of comparable size,” stated Scott, “and the two differ significantly in color, as well. Electrochemical measurements revealed that the planar and the warped nanographenes are equally easily oxidized, but the warped nanographene is more difficult to reduce.”
The new research was just published in the most recent online edition of the journal Nature Chemistry.