Ultra-hard carbon nitrides rival diamond

https://www.ed.ac.uk/news/2023/ultra-hard-material-to-rival-diamond-discovered

"carbon and nitrogen precursors subjected to pressures between 70 and 135 gigapascals and temperatures >1,500°C, resulting material tougher than cubic boron nitride, 2nd hardest material after diamond... 3 carbon nitride compounds retained diamond-like qualities when returned to ambient pressure and temperature conditions, also exhibiting photoluminescence, high energy density, ultra-incompressibility.... protective coatings for cars and spaceships, high-endurance cutting tools, solar panels and photodetectors"