Argonne researchers create new diamond-nanotube composite materialAugust 31, 2005Researchers at the U.S. Department of Energy's Argonne National Laboratory have combined the world's hardest known material - diamond - with the world's strongest structural form - carbon nanotubes. This new process for "growing" diamond and carbon nanotubes together opens the way for its use in a number of energy-related applications. The technique is the first successful synthesis of a diamond-nanotube nanocomposite, which means for the first time this specialized material has been produced at the nanometer size - one-millionth of a millimeter, or thousands of times smaller than the period at the end of this sentence. The result established for the first time a process for making these materials a reality, setting the stage for several fundamental advances in the field of nanostructured carbon materials.
The resulting material has potential for use in low-friction, wear-resistant coatings, catalyst supports for fuel cells, high-voltage electronics, low-power, high-bandwidth radio frequency microelectromechanical/nanoelectromechanical systems (MEMS/NEMS), thermionic energy generation, low-energy consumption flat panel displays and hydrogen storage. Diamond is called the hardest material because of its ability to resist pressure and permanent deformation, and its resistance to being scratched. Carbon nanotubes, which consist of sheets of graphitic carbon wrapped to form tubes with diameters only nanometers in size, are the strongest structures because they can withstand the highest tensile force per gram of any known material. "Diamond is hard because of its dense atomic structure and the strength of the bonds between atoms," said Argonne's John Carlisle, one of the developers of the new material. "The larger the distance between atoms, the weaker the links binding them together. Carbon's bond strength and small size enable it to form a denser, stronger mesh of atomic bonds than any other material." Diamond has its drawbacks, however. Diamond is a brittle material and is normally not electrically conducting. Nanotubes, on the other hand, are incredibly strong and are also great electrical conductors, but harnessing these attributes into real materials has proved elusive. By integrating these two novel forms of carbon together at the nanoscale a new material is produced that combines the material properties of both diamond and nanotubes. The new hybrid material was created using Ultrananocrystalline™ diamond (UNCD™ ), a novel form of carbon developed at Argonne. The researchers made the two materials - ultrananocrystalline diamond and carbon nanotubes - grow simultaneously into dense thin films. This was accomplished by exposing a surface covered with a mixture of diamond nanoparticles and iron nanoparticle "seeds" to an argon-rich, hydrogen-poor plasma normally used to make UNCD. The diamond and iron "seeds" catalyze the UNCD and carbon nanotube growth, respectively, and the plasma temperature and deposition time are regulated to control the speed at which the composite material grows, since carbon nanotubes normally grow much faster than ultrananocrystalline diamond. "Experimenting with these variables led us to the right combination," said Argonne's Jeffrey Elam, one of the developers. Added another of the developers, Xingcheng Xiao, "It is possible that the plasma environment causes local charging effects that cause attractive forces to arise between the ultrananocrystalline diamond supergrains and the carbon nanotubes. If so, such hybrid structures could have interesting electronic and photonic transport properties." The next step is to develop patterning techniques to control the relative position and orientation of the ultrananocrystalline diamond and carbon nanotubes within the material. "In addition, we hope to understand the structure and properties of these materials, particularly the mechanical, tribological and transport properties," developer Orlando Auciello said. The research was featured in the June on the cover of the peer-reviewed journal, Advanced Materials. The nation's first national laboratory, Argonne National Laboratory conducts basic and applied scientific research across a wide spectrum of disciplines, ranging from high-energy physics to climatology and biotechnology. Since 1990, Argonne has worked with more than 600 companies and numerous federal agencies and other organizations to help advance America's scientific leadership and prepare the nation for the future. Argonne is managed by the University of Chicago for the U.S. Department of Energy's Office of Science. Argonne National Laboratory | |||||||||||||||||||||
|
Related Carbon Nanotubes Current Events and Carbon Nanotubes News Articles Paperwork: Buckypapers clarify electrical, optical behavior of nanotubes Using highly uniform samples of carbon nanotubes-sorted by centrifuge for length-materials scientists at the National Institute of Standards and Technology (NIST) have made some of the most precise measurements yet of the concentrations at which delicate mats of nanotubes become transparent, conducting sheets. As Sticky as a Gecko ... but Ten Times Stronger! The gecko's amazing ability to stick to surfaces and walk up walls has inspired many researchers to manufacture materials that mimic the special surface of a gecko's foot. Simulations help explain fast water transport in nanotubes By discovering the physical mechanism behind the rapid transport of water in carbon nanotubes, scientists at the University of Illinois have moved a step closer to ultra-efficient, next-generation nanofluidic devices for drug delivery, water purification and nano-manufacturing. Coating improves electrical stimulation therapy used for Parkinson's, depression, chronic pain Researchers at UT Southwestern Medical Center have designed a way to improve electrical stimulation of nerves by outfitting electrodes with the latest in chemically engineered fashion: a coating of basic black, formed from carbon nanotubes. True properties of carbon nanotubes measured For more than 15 years, carbon nanotubes (CNTs) have been the flagship material of nanotechnology. Researchers have conceived applications for nanotubes ranging from microelectronic devices to cancer therapy. Their atomic structure should, in theory, give them mechanical and electrical properties far superior to most common materials. Slipping through cell walls, nanotubes deliver high-potency punch to cancer tumors in mice The problem with using a shotgun to kill a housefly is that even if you get the pest, you'll likely do a lot of damage to your home in the process. Hence the value of the more surgical flyswatter. Golden Scales: Nanoscale Mass Sensor from Berkeley Can Be Used to Weigh Individual Atoms and Molecules There's a new "gold standard" in the sensitivity of weighing scales. Using the same technology with which they created the world's first fully functional nanotube radio, researchers with Berkeley Lab and the University of California (UC) at Berkeley have fashioned a nanoelectromechanical system (NEMS) that can function as a scale sensitive enough to measure the mass of a single atom of gold. 'Nanonet' circuits closer to making flexible electronics reality Researchers have overcome a major obstacle in producing transistors from networks of carbon nanotubes, a technology that could make it possible to print circuits on plastic sheets for applications including flexible displays and an electronic skin to cover an entire aircraft to monitor crack formation. LLNL researchers peer into water in carbon nanotubes Researchers have identified a signature for water inside single-walled carbon nanotubes, helping them understand how water is structured and how it moves within these tiny channels. The fight for the best quantum bit (qubit) Our results give us, for the first time, the possibility to understand the interaction between just two electrons placed next to each other in a carbon nanotube. More Carbon Nanotubes Current Events and Carbon Nanotubes News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||