Researchers at the University of Cincinnati have grown the world's longest nanotubes: 3 millimeters beyond the prior world record!
A report says that while "still slightly less than 2 centimeters long, each nanotube is 900,000 times longer than its diameter," but: "More important for manufacturing, the research team grew a 12-millimeters-thick, uniform carpet of aligned carbon nanotubes on a roughly 10-centimeter silicon substrate, opening the door for scaling-up the process."
The researchers, led by professors Vesselin Shanov and Mark Schulz who worked in collaboration with post-doctoral researcher Yun Yeo Heung and students, developed a technique to grow the aligned bundles of tiny tubes. This consists in using chemical vapor deposition (a technique for creating thin coatings that is common in the semiconductor industry), with a novel substrate and catalyst onto which the carbon attaches.
Carbon nanotubes are an important theoretical building block of many proposed nanotechnologies. Combining them with more normal materials can greatly improve "mechanical, thermal and electrical properties."
"Ray H. Baughman at the NanoTech Institute has shown that single and multi-walled nanotubes can produce materials with toughness un-matched in the man-made and natural worlds."
Furthermore, the unique conduction of carbon nanotubes presents many opportunities for innovations in electrical engineering.
One possible application is being explored by India's Defence Research and Development Organisation DRDO is investing in a project at Punjab University's physics department to develop a material using carbon nanotubes which, when used as a coating, would increase the shock absorbing capacity of the object on which it would be coated.
Prof. V. K. Jindal, faculty member of the department who is overseeing the project, said "The tubes are very strong and are, hence, durable. One possibility is to make a liquid that can be used as the coating substance."
Nanotubes also "show superior transparency in the infrared part of the spectrum compared with other materials," says one news report, "an attribute scientists say could make the films important for military applications, such as disguising objects from an enemy’s night-vision equipment.
--Christina Mackenzie, David Axe and Sean Meade
(Photo Credit: V. Shanov, M. Schulz, University of Cincinnati)
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