14 DAY TRIAL // Scientists from the Massachusetts Institute of Technology (MIT) recently devised a method of producing carbon nanotubes that does not involve the use of regular metals, which appear to be interfering with materials found in circuits and composites. Nanotubes hold great promise for future electronic devices, and so developing them in a way that does not hinder the functions of the very devices they were created to augment is essential. The researchers learned that the compound zirconium oxide – which can also be found in fake diamonds – can provide the growth assistance needed, but with none of the side-effects associated with metals.
“I think this fundamentally changes the discussion about how we understand carbon nanotubes synthesis,” says the leader of the new study, MIT professor of aeronautics and astronautics Brian Wardle. He is also the author of paper detailing the find, published online in the August 10th issue of the Journal of the American Chemical Society (JACS). Until now, gold, cobalt and iron were used in the growing process, but they proved toxic and detrimental to clean room environments in labs across the world. Therefore, the need for a new method was considerable.
“People report new metals [as catalysts] every so often. But now we have a whole new class of catalyst and new mechanism to understand and debate,” Wardle adds. “Composites are durable, but fail under certain loading conditions, like when plywood flakes and splinters apart. But what if you could reinforce composites at the microlevel with nanotubes the way that rebar reinforces concrete in a building or a bridge? That's what we're trying to do to improve the mechanical properties and resistance to fracturing of carbon composites,” adds MIT graduate student Stephen Steiner, also the study's first author.
The work done at MIT could have significant and far-reaching consequences even for the aviation industry. More and more planes today are designed featuring composite materials, but their proportion in the overall amount of material used is only about 40 percent. The reason why more composites are not used is precisely their frailty. But, with the help of nanotubes, these materials could become significantly stronger, and would have the potential to save immense amounts of fuel each year.