Scientists have succeeded in developing "goldene," an extraordinarily thin version of gold. This comes after graphene, a material composed of single-layer graphite atoms, was successfully produced. It is extremely strong and conducts heat and electricity far more effectively than copper, which has led to it being heralded as a miracle material, as per a report in the Independent.
Goldene is based on the same idea, where scientists disperse gold until it is only one layer of atoms thick. Much like graphene, scientists claim that the technique provides it with a host of new properties that may pave the way for significant discoveries. The new substance has a wide range of potential applications, including communications technologies, water purification, carbon dioxide conversion, and much more, according to experts. Further, modern technologies that require gold can employ far less of the metal.
Scientists have stated that gold could just be one of a range of similar metals. They are researching to understand whether similar findings and methods could be used on other materials.
Shun Kashiwaya, researcher at the Materials Design Division at Linkoping University, said, "If you make a material extremely thin, something extraordinary happens - as with graphene. The same thing happens with gold. As you know, gold is usually a metal, but if a single atom layer thick, the gold can become a semiconductor instead."
This form of thin gold has been the subject of years of research, but attempts have been challenged by the tendency of metal to clump together. Finally, a century-old method developed by Japanese artisans provided the breakthrough. It also happened partly by luck. The novel material was discovered while searching for something else. It is based on the idea that gold is implanted between layers of carbon and titanium in a base material, as per the outlet.
"We had created the base material with completely different applications in mind. We started with an electrically conductive ceramic called titanium silicon carbide, where silicon is in thin layers. Then the idea was to coat the material with gold to make a contact. But when we exposed the component to high temperature, the silicon layer was replaced by gold inside the base material," Lars Hultman, professor of thin film physics at Linkoping University said.
The substance, created by an intercalation method, was available to researchers for a few years. However, they were unable to extract the gold itself from it. They then used a technique known as Murakami's reagent, which is used by Japanese smiths to remove carbon from materials, for instance, alter the colour of steel. The researchers then made some changes to the technique to extract the gold. "I tried different concentrations of Murakami's reagent and different time spans for etching. One day, one week, one month, several months. What we noticed was that the lower the concentration and the longer the etching process, the better. But it still wasn't enough," Mr Kashiwaya said.
Since light causes cyanide to form in the reaction and destroy gold, the etching had to be done in complete darkness. Stabilizing the gold sheets was the final step. A surfactant was applied to stop the exposed two-dimensional sheets from curling up. "The goldene sheets are in a solution, a bit like cornflakes in milk. Using a type of 'sieve', we can collect the gold and examine it using an electron microscope to confirm that we have succeeded. Which we have," he said.
