Researchers have discovered a new form of carbon structure, called Q-carbon, that's harder than diamond and allows artificial versions of the precious stone to be made at room temperature and pressure.
A team of material scientists from North Carolina State University has developed a new form of solid carbon that's different to the familiar graphite and diamond structures. The researchers suggest that it's unlikely to occur in the natural world — "the only place it may be found in the natural world would be possibly in the core of some planets", they explain in a press release.
Instead, it's made in the lab. To do so, the researchers take a surface like glass and coat it in what's referred to as amorphous carbon — essentially a scattering of carbon atoms that aren't yet neatly bonded together into a crystal structure like diamond. Then, they take a laser and fire 200 nanosecond pulses at the carbon, which causes rapid heating — to temperatures as high as 3727C — and cooling.
The result is what the team have dubbed Q-carbon. In a series of papers, including one published in the Journal of Applied Physics, the team explains that the new material is harder than diamond, can glow when exposed to energy, and is ferromagnetic, too.
By tweaking the production technique and changing how quickly the laser pulse heats and cools the carbon, the team can also create diamond structures at room temperature and pressure. Usually, synthetic diamond requires huge pressures during its formation.
There are, however, some compelling reasons why Q-carbon won't be on rings and drill tips just yet. Not least is the fact that the team can so far only produce sheets of the material which measure 20 nanometres to 500 nanometres in thickness — about 100 times thinner than the width of a typical human hair.
"We can make Q-carbon films, and we're learning its properties, but we are still in the early stages of understanding how to manipulate it," admits Jay Narayan, who led the research.