Argonne researchers create new diamond-nanotube composite material

August 30, 2005
Argonne researchers create new diamond-nanotube composite material

Researchers 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.

Image: COVER STORY – Argonne's carbon-nanotube research was featured on the June 2005 cover of the peer-reviewed journal, Advanced Materials.

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.

Source: Argonne National Laboratory

Explore further: Could stronger, tougher paper replace metal?

Related Stories

Could stronger, tougher paper replace metal?

July 24, 2015

Researchers at the University of Maryland recently discovered that paper made of cellulose fibers is tougher and stronger the smaller the fibers get. For a long time, engineers have sought a material that is both strong (resistant ...

Simulations lead to design of near-frictionless material

July 22, 2015

Argonne scientists used Mira to identify and improve a new mechanism for eliminating friction, which fed into the development of a hybrid material that exhibited superlubricity at the macroscale for the first time. Argonne ...

What is a terrestrial planet?

July 2, 2015

In studying our solar system over the course of many centuries, astronomers learned a great deal about the types of planets that exist in our universe. This knowledge has since expanded thanks to the discovery of extrasolar ...

Diamond-like coatings save fuel

June 8, 2015

Coating engine components with hard carbon reduces friction to almost zero – a development that could save billions of liters of fuel worldwide every year. Now researchers have developed a new laser method to apply the ...

Recommended for you

Magnetism at nanoscale

August 3, 2015

As the demand grows for ever smaller, smarter electronics, so does the demand for understanding materials' behavior at ever smaller scales. Physicists at the U.S. Department of Energy's Ames Laboratory are building a unique ...

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Study calculates the speed of ice formation

August 3, 2015

Researchers at Princeton University have for the first time directly calculated the rate at which water crystallizes into ice in a realistic computer model of water molecules. The simulations, which were carried out on supercomputers, ...

Small tilt in magnets makes them viable memory chips

August 3, 2015

University of California, Berkeley, researchers have discovered a new way to switch the polarization of nanomagnets, paving the way for high-density storage to move from hard disks onto integrated circuits.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.