Today in relatively obscure but nonetheless meaningful scientific pursuits: two researchers at the Max-Planck Institute claim to have turned hydrogen into metal. That may seem unremarkable, but the fact is hydrogen–being an alkali metal–should exhibit the qualities of a metal under the right circumstances. Yet no one has ever coaxed the universe’s most abundant element into showing metallic qualities until now. Perhaps.
This all depends on how you qualify the term “metal.” There are some boilerplate qualifiers: Metals should conduct electricity and heat somewhat well, they should be malleable to some degree, and it makes sense that they should exist as solids under some circumstances.
But though many have tried, none have been able to make hydrogen behave like a metal under these criteria. Mikhail Erements and Ivan Troyan claim in a paper published in Nature Materials that they’ve done exactly that.
First, they placed some hydrogen in an alumina-epoxy gasket and placed that within a diamond anvil cell. This allowed them to test the opacity and electrical resistance of their sample via laser and electrodes, respectively. Then, at room temperature, they dialed the pressure up to 220 gigapascals, at which point their sample became opaque and began to show conductive properties. In the next phase of their experiment, they also dialed down the temperature to roughly -400 degrees while upping the pressure to 260 GPa. Here, electrical resistance increased by 20 percent.
This, they claim, is hydrogen exhibiting metallic properties.
Now, other researchers are going to have to replicate the se results before they can be described as truly meaningful. And then peer reviewers are going to have to hash out whether or not these qualities truly constitute “metallic” characteristics. What is most interesting is that they made hydrogen gas conductive at room temperature by applying pressure. Materials scientists have long been looking for superconductors that can move electricity over distances without losing so much of it as waste. Perhaps hydrogen was right there staring them in the face all along.