Nanowires used to detect poisonous gases

A team of researchers from Pittsburgh University have developed a self-assembly method that uses scaffolds to grow gold nanowires.

The researchers have coaxed gold into nanowires as a way of creating an inexpensive material for detecting poisonous gases found in natural gas. The findings, entitled Welding of Gold Nanoparticles on Graphitic Templates for Chemical Sensing, have been published in the Journal of the American Chemical Society.

The new technique should lower the costs of gas detection, as chip-based sensors that rely on nanomaterials for detection are less expensive than bulky and equipment. The new equipment is also more portable, which will be beneficial for workers who could wear them to monitor poisonous gases.

Gold's high affinity for sulphur and the unique physical properties of nanomaterials make them ideal for detecting hydrogen sulphide. The research team experimented with carbon nanotubes and graphene and used computer modelling, X-ray diffraction and transmission electron microscopy to study the self-assembly process.

Alexander Star, associate professor of chemistry in Pittsburgh University’s Kenneth P Dietrich School of Arts and Sciences, said: "To produce the gold nanowires, we suspended nanotubes in water with gold-containing chloroauric acid.

"As we stirred and heated the mixture, the gold reduced and formed nanoparticles on the outer walls of the tubes. The result was a highly conductive jumble of gold nanowires and carbon nanotubes."

Posted by Joseph Hutton