Commentary Gyula Eres

Carbon Nanostructures for Everything   Gyula Eres   Materials Science and Technology Division   E-mail: eresg@ornl.gov

In this commentary I outline some ideas about the origin of the obstacles that currently hinder the development of carbon nanotube and graphene applications and I offer a solution to this problem.

The discovery of sp² based carbon nanostructures such as fullerenes, carbon nanotubes and graphene has generated enormous excitement in the scientific community culminating in the awarding of the Nobel prizes in 1996 and 2010.  The remarkable properties of these materials are promising to transform life as we know it creating technological breakthroughs in such diverse fields as medicine and space exploration.  However, the anticipated flood of applications has been slow to arrive because of the inability of current synthesis methods to produce carbon nanostructures with uniform and reproducible properties at an industrial scale.  The gap between the discovery of phenomena and their mass replication is by no means unique to carbon materials.  Indeed it marks the march of innovation throughout human history.  This gap is most obvious with carbon nanotubes.  Few of the potential applications have managed to get off the laboratory bench.  

The reason direct scale up of synthesis methods used in the discovery process fails to produce the same quality material in large amounts is hidden by the lack of understanding of the synthesis mechanism of these structures.  A molecular level understanding similar to the one that represents the foundation for multibillion dollar industries such as the polymer and the pharmaceutical industry does not exist for carbon nanomaterials.  The first step in overcoming these obstacles is a recognition that the current picture of carbon nanostructure formation by a purely physical process of carbon dissolution and precipitation is woefully inadequate for describing the complexities of the synthesis process.     

The elementary processes in carbon nanostructure formation occur by formation and transformation of carbon-carbon bonds.  Only fundamental understanding that is based on the remarkable richness and versatility of carbon-carbon bond chemistry is capable of identifying the reaction pathways that provide access to structures with desired properties.  The best indication that a new framework is needed can be seen by the fact that these nanostructures are more stable than anyone expected and are not turning into graphite as predicted by the rules of conventional carbon chemistry.  Understanding the assembly of carbon nanostructures on the molecular level is the most promising approach toward achieving structure specificity that is a prerequisite for uniformity of properties.   The ultimate objective is to abandon harsh synthesis conditions that unnecessarily widen the parameter space in current methods in favor of developing a form of "soft chemistry" that would be highly effective in synthesizing carbon nanostructures similar to conventional polymerization processes.