They make goldino, a material with unusual properties | Scientists from a Swedish university were able to make gold plates that are only one atom thick

It was achieved by a team of scientists For the first time, gold sheets one atom thick have been createdWhich gives this metal new properties with multiple applications, such as hydrogen production or manufacturing value-added chemical products. Is it Goldeno. Details of the discovery, made by researchers at Linköping University (Sweden), will be published on Tuesday in the journal Synthesis of nature.

As with graphene, “if you make a very thin material, something unusual happens, also with gold. As you know, gold is usually a metal, but If it had a layer one atom thick, it could become a semiconductor“Explains Shun Kashiwaya, a researcher at Linköping University and lead author of the study.

To make Goldeno, the team used a 3D base material, with gold embedded between layers of titanium and carbon, although part of the success was down to luck, says Lars Holtmann, a professor at Linköping University.

“We created the base material with completely different applications in mind. 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 make contact. But when we exposed the component to high temperatures, The silicon layer has been replaced with gold within the base material.”

This phenomenon is called “intercalation” and what the researchers discovered was titanium carbide and gold. For several years, researchers have been able to obtain titanium carbide and gold without knowing how to flake the gold, so to speak.

but after that, Holtmann discovered a method that has been used in Japanese blacksmithing for more than a hundred years, the Murakami detector. Which removes carbon residue and changes the color of steel and that It is used in the manufacture of knives, For example. But it was not possible to use exactly the same recipe as the blacksmiths. Modifications had to be sought. To do this, “I tried different concentrations of Murakami's reagent and different etching time periods,” Holtmann says.

The next step was to perform the etching in the dark, where the cyanide reacts with the light and dissolves the gold.

Finally, the gold sheets must be stable, and in order to prevent the exposed 2D sheets from warping, a surfactant (a long molecule that separates and stabilizes the sheets) is added.

“Goldno leaves are placed in a solution like cornflakes in milk. Using a type of “sieve” we can collect the gold and examine it with an electron microscope to make sure we have found it. “We made it happen,” says Kashiwaya.

New materials, new properties

Goldeno's new properties are due to the fact that gold contains two free bonds when it is two-dimensional.

The researchers believe that Goldino will facilitate future applications such as carbon dioxide conversion, catalysis for hydrogen generation, selective production of value-added chemicals, hydrogen production, water purification, communications and much more. In addition, the amount of gold used in current applications can be significantly reduced. The team will now investigate whether the same can be done with other noble metals and identify other future applications.