The following article was sent to us by Corey McCarren and Elena Polyakova from Graphene Laboratories, discussing carbon nanotubes commercialization woes, and how it relates to Graphene:
After the Nobel Prize was awarded for the research of graphene in October 2010, the material has occupied the headlines of all technology-related media. Graphene is already positioned as the next “big thing” for many technologies, such as computers, displays, biosensors, and flexible electronics, to name a few. It might be the right time to look back to 2001 when carbon nanotubes (closed rolls of graphene) were the “darlings of the day”, and headlines were full of promises of their bright future. Today, in 2011, most of these expectations were not realized.
Is the idea of commercialized carbon nanotubes a thing of the past? Is graphene doomed to repeat their fate?
A picture-perfect example of the problems facing carbon nanotube commercialization is those of a company in Massachusetts, Nantero, which has been developing commercial products, particularly Nanotube RAM (NRAM), using carbon nanotube technology, for years. Fueled by the findings of Harvard Scholars, Nantero attracted more than $30 million of investment and had almost 50 employees at its peak. Nantero founders and executives, Greg Schmergel and Dr. Thomas Reuckes, originally believed that carbon nanotubes would allow for improved storage space for computers and cellular phones, as well as allowing devices to be fully running the nano-second that they have been turned on. The company claimed that microchips which can fulfill these expectations would be on the market by 2004, yet it is 2011 and they have not yet achieved commercial success, despite the large investment in their company.
So what were the major hurdles Nantero encountered? The answer is the intrinsic problems of carbon nanotubes themselves, including the lack of control of physical and chemical properties, difficulties in scalability, as well as the high cost of production and purification.
First, Carbon nanotubes have suffered from the absence of reliable methods to produce arrays of nanotubes with identical properties since their discovery. In particular, atoms in carbon nanotubes can be arranged in multiple different ways, each batch of which has tubes with different chirality. One aptly named armchair, another which is zigzagged, as well as intermediate. Chirality critically affects the physical properties of carbon nanotubes, limiting the range of their applications. On the other hand, graphene does not suffer from this issue as all graphene sheets are identical, and therefore its properties are easily reproduced.
The second reason is poor scalability and high cost of production. Initially, only small quantities of the material was commercially available, therefore it was a challenge for universities and other research groups to purchase carbon nanotubes for testing so they may eventually go to market. In addition, carbon nanotubes are typically contaminated by metallic catalysts used during synthesis, as well as by other carbonaceous materials such as soot and require extensive purification before use, further increasing production costs. In contrast, after just a few years of research, effective and scalable methods of graphene have been developed and a wealth of graphene materials are commercially available, allowing researchers all over the world to study graphene and make rapid advancements.
Not all has been lost for carbon nanotubes. Though carbon nanotubes have not yet proven their worth in computing, which is what Nantero was invested in, they are useful for a handful of commercial products. A bicycle with a frame partly made of carbon nanotubes entered the 2005 Tour de France, showing that the light weight and strength of carbon nanotubes does have commercial potential. Graphene has proven itself a stronger material than carbon nanotubes at a fraction of the weight and cost. It is expected to replace carbon nanotubes in most of applications where carbon materials are incorporated in matrices to enhance materials properties.
To finish the story of Nantero on a positive note, in 2008, the government business subdivision of Nantero was bought by Lockheed Martin, a global aircraft and security company. They have tested the durability of prototype NRAM devices during launch, airtime, and return, and have found that NRAM can survive the harsh radiation of space. The NRAM devices performed the same in orbit as they did when they returned. It was not, however, reported as to how well the devices performed overall.
Limited success of early pioneers of nanoscience such as Nantero should not cause distrust in the wonders of nanotechnology. Time will tell if Nantero can someday apply its idea of NRAM to actual devices, but it is important that lessons learned from the past are applied to new emerging nanomaterials. Graphene, as a vivid example, has many advantages over carbon nanotubes, and is already being tested for a multitude of future applications. We strongly believe that graphene will be the first in a long line of nanoproducts to achieve commercial success.