Artistic rendition of a metallic carbon nanotube being pulled into solution, in analogy to the work described by the Adronov group.
Imagine an electronic newspaper that you could roll up and spill your coffee on, even as it updated itself before your eyes. It’s an example of the technological revolution that has been waiting to happen. Researchers at McMaster University have developed a new way to purify carbon nanotubes – smaller, flexible semiconductors expected to replace silicon within computer chips and a wide array of electronics. “Once we have a reliable source of pure nanotubes that are not very expensive, a lot can happen very quickly,” says Prof Adronov.
A major problem standing in the way of the new technology, however, has been untangling metallic and semiconducting carbon nanotubes, since both are created simultaneously in the process of producing the microscopic structures, which typically involves heating carbon-based gases to a point where mixed clusters of nanotubes form spontaneously as black soot.
Only pure semiconducting or metallic carbon nanotubes are effective in device applications, but efficiently isolating them has proven to be a challenging problem. Even when the nanotube soot is ground down, semiconducting and metallic nanotubes are knotted together within each grain of powder. Both components are valuable, but only when separated.
While previous researchers had created polymers that could allow semiconducting CNTs to be dissolved and washed away, leaving metallic nanotubes behind, there was no such process for doing the opposite: dispersing the metallic nanotubes and leaving behind the semiconducting structures. Now, Adronov’s group has managed to reverse the electronic characteristics of a polymer known to disperse semiconducting nanotubes – while leaving the rest of the polymer’s structure intact. By so doing, they have reversed the process, leaving the semiconducting nanotubes behind while making it possible to disperse the metallic nanotubes.
The next step, he explains, is for his team or other researchers to exploit the discovery by finding a way to develop even more efficient polymers and scale up the process for commercial production. http://www.eurekalert.org/pub_releases/2016-08/mu-mr081616.php
http://onlinelibrary.wiley.com/doi/10.1002/chem.201602722/abstract
Recent Comments