Graphene is often hailed as the wonder material of the future, and this latest breakthrough connects it to another class of materials that people believe will change the world: superconductors.
An international group of researchers has found a way to make graphene superconductive, allowing the material to conduct electricity without resistance. The result, published in Nature Communications, was possible by combining graphene with praseodymium cerium copper oxide (PCCO), a known superconductive material.
“It has long been postulated that, under the right conditions, graphene should undergo a superconducting transition, but can’t,” co-author Dr Jason Robinson, from Cambridge University, said in a statement. “The idea of this experiment was, if we couple graphene to a superconductor, can we switch that intrinsic superconductivity on? The question then becomes how do you know that the superconductivity you are seeing is coming from within the graphene itself, and not the underlying superconductor?”
Scientists are extremely familiar with the properties of PCCO superconductivity. When temperatures are low enough, the electrons of PCCO form pairs with spins pointing in opposite directions. But when the same is done with the graphene-bound PCCO, the electrons aren't in that configuration at all.
“What we saw in the graphene was, in other words, a very different type of superconductivity than in PCCO,” Robinson added. “This was a really important step because it meant that we knew the superconductivity was not coming from outside it and that the PCCO was therefore only required to unleash the intrinsic superconductivity of graphene.”
Graphene is 200 times stronger than steel and it’s in sheets only 2 atoms thick, making it also incredibly flexible. Its ability to superconduct and the ease with which it connects with other molecules can be used to create a new type of electronics.
“In principle, given the variety of chemical molecules that can bind to graphene’s surface, this research can result in the development of molecular electronics devices with novel functionalities based on superconducting graphene,” lead author Dr Angelo Di Bernardo stated.
Scientists and engineers are investigating the possibility of having superconductors at room temperature. It would be interesting to see if graphene’s superconductivity can be activated at any temperature.
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