Diamonds are famously formed under high pressure and temperature, which is partly why they’re so valuable. But now, scientists have created diamonds in a lab under regular pressure in just 15 minutes.
Diamonds are basically just plain old carbon that’s been put under immense pressure and temperature, causing the atoms to crystallize into a particular structure. On Earth, the only place with the right natural conditions is deep in the mantle, hundreds of miles down. Only later are they brought closer to the surface, hitching rides in volcanic eruptions, which makes them pretty rare. Couple that with some of the most insidious marketing in history, and you’ve got a highly sought-after little rock.
Scientists have been growing diamonds in labs for decades, but it usually still needs those extreme conditions – almost 50,000 atmospheres of pressure, and temperatures of about 1,500 °C (2,732 °F). But a new technique has now produced diamonds under normal pressure levels and cooler temperatures.
The new method, developed by a team from the Institute for Basic Science (IBS) and the Ulsan National Institute of Science and Technology (UNIST) in South Korea, synthesizes diamonds using a liquid metal alloy of gallium, iron, nickel and silicon. In a 9-L (2.4-gal) tank, this metal mix is exposed to methane and hydrogen gas at a temperature of 1,025 °C (1,877 °F). After 15 minutes, the gas is purged from the system, and a diamond film will have formed on the bottom. This can be detached easily and used for studies or put straight to work.
Usually, synthetic diamond techniques need “seed particles” for the first carbon atoms to latch onto and form a diamond around. But in this case, the trace amounts of silicon in the liquid metal seem to help the carbon atoms form clusters. The end result is a very pure diamond. The other metals can be switched in and out, but it seems that silicon is essential to the process.
The researchers now plan to investigate other liquid metal alloys and gases, and even solid carbons, for how well they might be able to make diamonds. While it’s not likely we’ll be wearing diamonds grown in liquid metal vats any time soon, they could find use in industrial applications first.
The research was published in the journal Nature.
Source: IBS
