Steel Tubing Used to Grow Carbon Nanotubes

In less than 20 minutes, researchers can now seed, heat and grow carbon nanotubes in 10-foot-long, hollow thin steel tubing. The ground-breaking method will lead to improvements in cleaner gasoline, better food processing and faster, cheaper ways to clean air and water, the scientists said.

“The work took us three years to develop and get right, but now we can essentially anchor nanotubes to a tubular wall. No one has ever done anything like this before,” said lead researcher Somenath Mitra, PhD, professor and acting chair of the New Jersey Institute of Technology (NJIT) department of chemistry and environmental science. Graduate and post-doctoral students who worked on the project are Mahesh Karwa, Chutarat Saridara and Roman Brukh.

A carbon nanotube is a molecular configuration of carbon in a cylindrical shape. The name is derived in part from the tube’s miniscule size. Scientists estimate nanotubes are 50,000 times smaller than a human hair and can be used to improve strength, durability and other properties of materials.

Until recently, researchers have relied on the nanotubes which can be purchased as a powder and mixed with polymers or chemicals to make films and composites. However, the method has drawbacks.

“We have never been able to anchor the powder to a large surface, nor can we grow the nanotubes in a large device. Typically we could only produce them in minute amounts, if we used the powder substance,” said Mitra. Now everything has changed.

Using a catalyst either prepared on the steel surface or enabled by a chemical deposition process, the NJIT inventors have created nanotubes which can stick to the walls of narrow or wide tubes. And, they can grow considerably larger amounts of them, making the process more attractive and viable for industrial usages.

The discovery was described in the June 14 issue of Journal of Material Chemistry. Their work has also been featured in Chemical Physics Letters and Carbon and Analytical Chemistry.

Mitra's other research interests include chemically altering carbon nanotubes, finding analytical techniques and sensors to discover low-level trace elements in air, water and soil. His projects include the development of instrumentation and methods for continuous, online analysis of trace levels of organic pollutants in air and water. His work is funded by the Environmental Protection Agency, Department of Defense, the National Science Foundation and others.

For more information, visit: www.njit.edu