A group of scientists have created “goldeno”: sheets of gold one atom thick with extraordinary properties.

For the first time, a team of scientists has succeeded in creating gold sheets that are one atom thick, giving the metal new properties that can be used in a variety of applications, such as producing hydrogen or producing value-added chemicals. He ‘gold’.

Details of the discovery, made by researchers from Linköping University (Sweden), were published on Tuesday in the journal Nature Synthesis.

As with graphene, “if you make a very thin material, something extraordinary happens, including with gold. As is known, Gold is usually a metal, but if it has a layer one atom thick, it can become a semiconductor.explains Shun Kashiwaya, a researcher at Linköping University and lead author of the study.

To create the Goldeno, the team used a 3D base material in which gold is sandwiched between layers of titanium and carbonalthough part of the success is down to luck, says Lars Hultman, a professor at Linköping.

“We created the base material for completely different purposes. We started with an electrically conductive ceramic called titanium-silicon-carbide, where the silicon is in thin layers. So the idea was to coat the material with gold to ensure contact. When we exposed the component to high temperatures, the layer of silicon in the base material was replaced by gold,” he explains.

This phenomenon is called “intercalation”, and the researchers discovered titanium carbide and gold. For several years, researchers had titanium carbide and gold at their disposal without knowing how the gold could be exfoliated, so to speak.

But then Hultman found a method that has been used in the art of Japanese forging for more than a hundred years – Murakami’s reagent, which eliminates traces of carbon and changes the color of steel and is used, for example, in the manufacture of knives. .

But it was not possible to use exactly the same recipe that the blacksmiths used. I had to look for modifications.

To do this, “I tried different concentrations of Murakami reagent and different etching times,” says Hultman.

The next step was to engrave in the dark, as the cyanide reacts with light and dissolves the gold.

Finally, the gold sheets needed to be stable, so to prevent the exposed 2D sheets from curling, a surfactant (a long molecule that separates and stabilizes the sheets) was added.

“Gold flakes are in solution, like corn flakes in milk. Using a “sieve” of sorts, we can collect the gold and examine it with an electron microscope to confirm that we have achieved it. And we achieved it,” he says to Kashivaya.

The new properties of gold are due to the fact that two-dimensional gold has two free bonds.

Researchers They believe Goldeno will facilitate future applications such as carbon dioxide conversion, hydrogen generation catalysis, selective production of value-added chemicals, hydrogen production, water purification, communications and more.

Additionally, the amount of gold used in current applications could be significantly reduced.

The team will now investigate whether the same can be done with other noble metals and identify other future applications.

(according to EFE)