Researchers at the Max Planck Institute for Chemistry in Mainz and the Johannes Gutenberg University Mainz observed that hydrogen sulfide becomes superconductive at minus 70 degree Celsius —when the substance is placed under a pressure of 1.5 million bar. This corresponds to half of the pressure of the earth’s core. With their high pressure experiments the researchers in Mainz have thus not only set a new record for superconductivity— their findings have also highlighted a potential new way to transport current at room temperature with no loss.
The work was published in Nature Materials Journal (link) on August 17, 2015. The first original results were released in Cond. Mat. (arxiv) back on December 2014.
Soon after the discovery in the H-S system, we predicted another system with fairly similar characteristics: transition temperatures of the order of 100 K could be reached in principle in H-Se system at lower pressures. This research is publicly available in arxiv and it was first show on 26 January 2014.