Liquid metal synthesis of diamonds achieved at atmospheric pressure

Diamonds have been synthesised at atmospheric pressure by researchers in South Korea. The researchers do not yet fully understand the underlying mechanism that forms these diamond films, but it involves passing methane over liquid gallium. They are working, however, to optimise the synthesis to produce higher-quality diamonds that they hope could find a range of uses.

Diamonds are not just the most expensive gemstones in the world: they have important uses in science and technology, ranging from drill bits to quantum computing. Researchers have therefore developed various ways to synthesise diamonds including advanced types of chemical vapour deposition. Around 99% of artificial diamonds, however, are produced using modifications of a technique developed at General Electric in the 1950s. This involves placing a small seed diamond on iron sulfide and heating it to 1600°C in the presence of a carbon source at 7GPa. As the sulfide melts, the carbon source gradually converts into diamond and grows around the original seed.