Researchers have come up with a new technique that uses the world's tiniest diamonds to make tiny wires measuring just three atoms wide.

Study researcher Fei Hua Li, from Stanford Institute for Materials and Energy Sciences, and colleagues used the smallest possible bits of diamonds known as diamondoids to assemble atoms into very thin wires.

Diamondoids are strongly attracted to each other through van der Waals forces, which cause the microscopic diamonds to cluster together into sugar-like crystal. They can potentially help in making tiny electronic gadgets and improve electron microscope images.

LEGO-Style Assembly Of Different Atoms

To make the wire, the researchers employed a technique that involves putting together various types of atom LEGO-style. Just like in LEGO blocks, the size and shape of the atoms determine if the atoms fit together.

"Much like LEGO blocks, they only fit together in certain ways that are determined by their size and shape," Li said. "The copper and sulfur atoms of each building block wound up in the middle, forming the conductive core of the wire, and the bulkier diamondoids wound up on the outside, forming the insulating shell."

The researchers used diamondoids with interlocking cages of hydrogen and carbon as assembly tools. Over the past decade, researchers have been looking at the potential uses for the little diamonds, which are naturally found in petroleum fluids and are extracted and filtered by size and geometry.

Li and colleagues started out with single cages of the diamondoids containing just 10 carbon atoms and then attached a sulfur atom to each of these. The sulfur-linked diamondoids were then dropped in a solution of copper atoms where the copper would link to the sulfur atom.

With the sulfur atom now attached to a diamondoid and a copper atom, the structure would drift toward other structures forming a wire composed of a string of copper and sulfur atoms that are surrounded by the diamond.

"Here, we report that strongly interacting diamondoid structure-directing agents guide the growth of hybrid metal-organic chalcogenide nanowires with solid inorganic cores having three-atom cross-sections, representing the smallest possible nanowires," Li and colleagues wrote in their study, which was published in Nature Materials on Dec. 26.

Potential Applications

The method may be used to build tiny wires with a wide range of applications such as in optoelectronic devices that use electricity and light, electricity-producing fabrics, and superconducting materials that can efficiently conduct electricity without loss.