Scientists in the United Kingdom have created a new form of gold just two atoms thick that shows remarkable versatility for novel uses in applications that range from electronics to diagnostics to catalysis.
A team at the University of Leeds has developed gold that’s 0.47 nanometers thick—or a million times thinner than a human fingernail. The material is considered two-dimensional (2D) because it comprises just two layers of atoms sitting on top of one another, researchers said.
|Researchers at the University of Leeds have developed a new form of gold that is a versatile, 2D material. Here an electron microscope picture shows the gold atoms' lattice structure. (Image source: University of Leeds)|
In fact, the material could be compared to another 2D material, graphene, which also has shown wide versatility in its potential uses. Indeed, it shows similar diversity, in part because all of the atoms in the gold are surface atoms--which bodes well for its use in new applications, University of Leeds Professor Stephen Evans told Design News.
“This means every atom is in principle available for catalytic and/or enzymatic reactions,” said Evans, who heads the Leeds' Molecular and Nanoscale Research Group and supervised the current research. “[The material] could also be interesting as a flexible transparent conducting coating for display devices or as interconnects in electronics.”
Specifically, Evans’ team developed a new process in which rigid liquid-crystal molecules that are known to self-assemble in solution form 2D and 3D structures that are used to constrain the gold, he told Design News. This caused the gold to grow in 2D sheets rather than a 3D crystal, Evans said. Researchers then removed the liquid-crystal molecules, leaving the gold behind.
Researchers started their synthesis of the material with chloroauric acid, an inorganic substance that contains gold. Once it was reduced to metallic form, it appears green in water and in a frond-like shape, inspiring researchers to describe it as “nanoseaweed.”
Researchers didn’t set out in their work with the goal of developing an ultra-thin form of gold in mind, Evans told us. Instead, they “set out to create gold of controlled thickness, using the liquid-crystal molecules to act as a template to control the growth through confinement,” he told Design News.
No matter, they have now developed a new material that could have wide-scale applications in the medical device and electronics industries, and also as a catalyst to speed up chemical reactions in a range of industrial processes, researchers said.
The latter use could be of particular interest, as lab tests show that the ultra-thin gold is 10 times more efficient as a catalytic substrate than the larger gold nanoparticles currently used industrially, researchers said.
Scientists believe the new material could also be used as a base material for artificial enzymes that could be used in rapid, point-of-care medical-diagnostic tests as well as on-the-spot water-purification systems.
Researchers published a paper detailing their work in the journal Advanced Science.
The team plans to continue their work to find ways to scale the process up to manufacture the material in larger quantities. They also aim to explore whether the process can be used to develop other materials besides gold, Evans told Design News.
Elizabeth Montalbano is a freelance writer who has written about technology and culture for more than 20 years. She has lived and worked as a professional journalist in Phoenix, San Francisco and New York City. In her free time she enjoys surfing, traveling, music, yoga and cooking. She currently resides in a village on the southwest coast of Portugal.
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