Carbon nanowires obtained by tempering diamantane dicarboxylic acid inside carbon nanotubes

Mar 06, 2013
Carbon nanowires obtained by tempering diamantane dicarboxylic acid inside carbon nanotubes

(Phys.org) —Carbon-based nanomaterials have unique properties that make them useful for many technical applications, including lightweight construction, electronics, energy generation, environmental technology, and medicine. In the journal Angewandte Chemie, an international team of researchers has now introduced a new process for the production of especially fine carbon nanowires from carbon in the diamond configuration. In this process, molecules with a diamond-like structure are linked together inside a carbon nanotube.

Carbon occurs in several configurations. Graphite and diamond have long been known. While graphite consists of two-dimensional, honeycomb-like sheets of carbon, diamonds are three- dimensional, cage-like structures consisting of puckered six-. A variety of new nanoconfigurations have also been discovered: fullerenes, carbon nanotubes, graphene (graphite monolayers), nanodiamonds, and diamondoids. Diamondoids are actually cycloalkane molecules with a skeleton of carbon configured in "cages", like diamond. They can be viewed as miniature diamonds with bound to their outer surfaces.

Nanowires are needed for many . Various types of nanowire have been produced, including some with diameters ranging from about 50 to 100 nm, made of carbon in the diamond configuration. A team of researchers from Japan, China, Germany, and the USA wanted to reduce the dimensions of nanowires further into the sub-nanometer range. Such tiny wires could be of use in the tips of scanning tunneling microscopes, which are devices that can be used to scan the topology of a surface to produce extremely high-resolution images.

Researchers led by Hisanori Shinohara at Nagoya University (Japan) came up with the idea of fusing diamondoids into longer, superfine wires. To make this work they had to resort to a trick: carbon nanotube "molds". For their starting material, the scientists chose diadamantane, a diamondoid made of two diamond-like cages. They attached a carbonic acid group at each end of these molecules. The molecules are transferred to the gas phase for the synthetic procedure. They are sucked into the tiny carbon nanotubes by capillary action. The best nanotube molds were found to be those with an inner diameter of about 1.3 nm. Within the nanotubes, the diamondoids line up like a string of pearls. Heating these to about 600 °C under a hydrogen atomsphere causes a polymerization/fusion reaction in which the individual diamondoid molecules link up through their carbonic acid groups to form a long "wire" with a diameter of about 0.78 nm. The cage-like structure is maintained.

By using theoretical calculations and various analytical techniques, the scientists were able to demonstrate that the carbon in the wires is indeed in a diamond-like structure.

Currently, the scientists are elaborating an ultrasonication extraction technique for releasing the from the surrounding carbon nanotubes.

Explore further: Thinnest feasible nano-membrane produced

More information: Evidence of Diamond Nanowires Formed inside Carbon Nanotubes from Diamantane Dicarboxylic Acid, Angewandte Chemie International Edition, dx.doi.org/10.1002/anie.201209192

Related Stories

New carbon allotrope could have a variety of applications

Apr 22, 2011

(PhysOrg.com) -- Carbon comes in many different forms, and now scientists have predicted another new form, or allotrope, of carbon. The new form of carbon, which they call T-carbon, has very intriguing physical ...

Structure of new form of super-hard carbon identified

Nov 08, 2010

(PhysOrg.com) -- An experiment in 2003 formed what was believed to be a new form of carbon, but the findings were controversial. Now two teams of scientists have used different means to identify a three-dimensional ...

Recommended for you

Thinnest feasible nano-membrane produced

22 hours ago

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

Wiring up carbon-based electronics

Apr 17, 2014

Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered ...

Making 'bucky-balls' in spin-out's sights

Apr 16, 2014

(Phys.org) —A new Oxford spin-out firm is targeting the difficult challenge of manufacturing fullerenes, known as 'bucky-balls' because of their spherical shape, a type of carbon nanomaterial which, like ...

User comments : 3

Adjust slider to filter visible comments by rank

Display comments: newest first

NikFromNYC
1 / 5 (4) Mar 06, 2013
"They are sucked into the tiny carbon nanotubes by capillary action."

Capillary action involves the surface tension of liquids, so this statement is ridiculous.
Husky
not rated yet Mar 07, 2013
its exactly because the surface interface of liquids is like a 2-d sheet exhibiting quantum behaviour on the nano scale as opposed to the vast underlying body of water, so in a sense you are both right and wrong, but hey thats quantum physics.
Graeme
not rated yet Mar 14, 2013
The monomer substance should have been called diamantane rather than diadamantane.

More news stories

'Exotic' material is like a switch when super thin

(Phys.org) —Ever-shrinking electronic devices could get down to atomic dimensions with the help of transition metal oxides, a class of materials that seems to have it all: superconductivity, magnetoresistance ...

Innovative strategy to facilitate organ repair

A significant breakthrough could revolutionize surgical practice and regenerative medicine. A team led by Ludwik Leibler from the Laboratoire Matière Molle et Chimie (CNRS/ESPCI Paris Tech) and Didier Letourneur ...

Thinnest feasible nano-membrane produced

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

Continents may be a key feature of Super-Earths

Huge Earth-like planets that have both continents and oceans may be better at harboring extraterrestrial life than those that are water-only worlds. A new study gives hope for the possibility that many super-Earth ...

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...