It turns out that hydrogen sulfide, the same compound that smells like rotten eggs, becomes a superconductor when solidified under pressure. And not only that, but it has recently be shown that it becomes a superconductor at a record highest transition temperature of 203.5 K.
Still, there are two points here that may make this not as "exciting" as one wold hope for. Earlier theoretical studies have predicted this to occur, and this material is expected to be a conventional superconductor mediated by phonons.
But the other issue, as in the practical aspect of this, may be even less enticing. This is because this material becomes a superconductor only under very high pressures.
The result may revive visions of superconductors that work at room temperature and magnetically levitated trains. But there's a catch: Hydrogen sulfide works its magic only when squeezed to more than 100 million times atmospheric pressure, roughly one-third as high as the pressure in Earth’s core. This condition makes it impractical for most applications. “Where does it go from here?” asks Igor Mazin, a theorist at the U.S. Naval Research Laboratory in Washington, D.C. “Probably nowhere.” Even so, the discovery is already altering the course of research in superconductivity.
So, while I think this is an exciting discovery, I'm not sure how much it will add to the physics and to applications..... yet.