LK-99

LK-99 is a gray-black, polycrystalline compound that potentially is a room-temperature superconductor. It is said to have a hexagonal structure that is slightly modified from lead‒apatite by adding small amounts of copper. A team from Korea University led by Sukbae Lee (이석배) and Ji-Hoon Kim (김지훈) began studying this material in 1999. According to their claims, LK-99 acts as a superconductor at temperatures below 400 K and at ambient pressure.