In discovering a new solid state for carbon scientists have also discovered that it is a relatively inexpensive way to produce diamonds.
Professor Jay Narayan of North Carolina State University is the lead author of three papers describing the work that sees Q-carbon join the growing list of carbon solids, a list that includes graphite, graphene, fullerene, amorphous carbon and diamond. He has suggested that the only place Q-carbon might be found in the natural world is in the core of certain planets.
The researchers created Q-carbon by starting with a thin plate of sapphire (other substrates, such as glass or a plastic polymer, will also work). Using a high-power laser beam, they coated the sapphire with amorphous carbon, a carbon form with no defined crystalline structure. They then hit the carbon with the laser again, raising its temperature to about 4,000 Kelvin, and then rapidly cooled, or quenched, the melted carbon. This stage of quenching is where “Q” in Q-carbon comes from.
The researchers have found that, depending on the substrates, tiny diamonds will form within the Q-carbon, suggesting to me that they have actually discovered how diamonds are formed deep below the Earth. The hot high pressure environment there allows Q-carbon to naturally form, and in the process of its solidification diamonds are a byproduct.