Scientists at Linköping University in Sweden have successfully created the world’s thinnest gold foil, known as “goldene”, which is just one atom thick. This material has unique optical, electronic, and catalytic properties that make it suitable for various applications in carbon dioxide conversion and hydrogen production.
The researchers used a 100-year-old technique used by Japanese ironsmiths to separate layers of gold in order to achieve this breakthrough. They developed a multi-layer structure of titanium, silicon, and carbon and coated the surface with gold, allowing the gold particles to disperse and replace the silicon layer. By carefully separating the surrounding solid mass using a 100-year-old chemical etching method, they were able to isolate the goldene layer intact.
The team further refined their method by experimenting with different reaction conditions and etching solution densities. They discovered that adding the amino acid cysteine as a surfactant helps stabilize the separated layer and prevent gold atoms from forming nanoparticles. The resulting goldene layer is up to 100 nanometers long and significantly thinner than regular gold leaf.
Due to its enhanced chemical reactivity, goldene holds promise for applications in converting carbon dioxide into fuels like ethanol and methane, as well as producing hydrogen from water. The researchers are continuing to optimize their synthesis method for further advancements in this groundbreaking material.