Physicists create a material similar to graphene

An international team of scientists says they have succeeded in making stanene. Stanene is a two-dimensional layer of tin atoms in a honeycomb structure, similar to graphene. Being able to make the material was predicted two years ago.

The fabrication seems successful, but the scientists report in the journal Nature Materials that they have not yet been able to confirm whether the material has the ‘fantastic’ electronic properties predicted two years ago, such as conducting electricity without generating residual heat at room temperature. . That’s because the material the scientists formed the stanene on interacts with the tin atomic structure.

Stanene, derived from the Latin word for tin stannum, is like other contemporary flat materials such as graphene, a topological insulator. The advantage of a topological insulator is that it behaves as an electrical insulator inside, but at the same time forces the electrons to the surface or edges of the material. The idea is that electrons can then travel that path without resistance, which in most cases only occurs at low temperatures.

Two years ago’s research on stanene, published in the journal Physical Review Letters, suggested that tin in its flat form could be used as a material to conduct electrons at room temperature without resistance. Calculations even showed that a combination with fluoride should make the electrons move without resistance up to a hundred degrees Celsius, but that was only theory. The stanene-fluoride combination could open up new avenues for room temperature superconductivity, as ExtremeTech and Stanford University, among others, disclosed two years ago.

In a background article on the Nature site, the German physicist Ralph Claessen doubts whether it is certain that stanene was actually made. The theory predicts that the two-dimensional structure should be a ‘kinked’ honeycomb, with the atoms pointing alternately up and down, creating ridged edges. The latter would not have been visible well enough on the images from the scanning tunnel microscope. With the publication of their article, the researchers show that they are certain about the material formed. But, as with graphene, it can take years before the material can have practical applications.

Staneen: on the left the images from the stm, on the right a model of stanene lying on the bismuth telluride substrate. Source: Nature