Scientists Use World's Smallest Diamonds To Make Wires Three Atoms Wide [STUDY]

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The Researchers at Stanford University and the Department of Energy's SLAC National Accelerator Laboratory have found a new way to use diamondoids - the smallest possible bits of diamond, to assemble atoms into the thinnest possible electrical wires, just three atoms wide.

By picking different types of atoms and putting them together LEGO-style, the technique could be used to build tiny wires for a wide range of uses, including fabrics that generate electricity, optoelectronic devices that uses both electricity and light, and super-conducting materials that conduct electricity without any loss.

"What we have shown here is that we can make tiny, conductive wires of the smallest possible size that essentially assemble themselves," Hao Yan, lead author of the study and a Stanford postdoctoral researcher says.

 "The process is a simple, one-pot synthesis. You dump the ingredients together and you can get results in half an hour. It's almost as if the diamondoids know where they want to go," Yan added.

Although, there are several other ways to get materials to self-assemble, this is the first one shown to make a nano-wire with a solid, crystalline core that has good electronic properties, according to the study co-author Nicholas Melosh, an associate professor at SLAC and an investigator with the Stanford Institute for Materials and Energy Sciences at SLAC (SIMES).

The needle-like wires have a semi-conducting core - a combination of copper and sulfur known as chalcogenide which are surrounded by the attached diamondoids to form an insulating shell, according to Eurekalert.

Melosh noted that their minuscule size is important, because a material which exists in just one or two dimension such as atomic-scale dots, wires or sheets, can have different, extraordinary properties when compared to the same material made in bulk.

The new method allows scientists to assemble the materials with atom-by-atom precision and control. The diamondoids used as assembly tools are tiny, interlocking cages of carbon and hydrogen. They can be found naturally in petroleum fluids. They are extracted in a SLAC laboratory and separated in consideration of their size and geometry.

The team took advantage of the diamondoids strong attraction to each other, through what is called "van der Waals" forces. They started with the smallest possible diamondoids - single cages which contain 10 carbon atoms and attached a sulfur atom to each. Floating in a solution, each of the sulfur atom bonded with a single copper ion and created the basic nanowire building block.

The building blocks then drifted toward each other, due to the van der Waals attraction between the diamondoids and attached to the growing tip of the nanowire, according to Sciencedaily.

They already used diamondoids to make one dimensional nanowires based on cadmium, iron, zinc and silver, with others that grew long enough to be visible even without a microscope. They conducted an experiment by carrying out the reactions in different solvents and other types of rigid, cage-like molecules like carboranes.

The researchers led by SIMES Director Thomas Devereaux predicted the electronic properties of the nanowires, which were examined with X-rays to determine their structure and other characteristics at SLAC's Stanford Synchrotron Radiation Lightsource - a DOE Office of Science User Facility.

The team included researchers from Stanford Department of Material Science and Engineering, National Autonomous University of Mexico (UNAM), Lawrence Berkeley National Laboratory and Justus-Liebig University in Germany.

Parts of the study were conducted at National Energy Research Scientific Computing Center (NERSC) and Berkeley Lab's Advanced Light Source (ALS), both DOE Office of Science User Facilities. The research was funded by the German Research Foundation and the DOE Office of Science.

A SIMES research program led by Melosh and Stanford Professor Zhi-Xun Shen over the past decade discovered a number of potential uses for the little diamonds such as making tiny electronic gadgets and improving electron microscope images. The scientists published their findings in Nature Materials.