Researchers created new phase of diamond at room temperature
By Staff Writer
Diamond is considered the hardest substance on earth. But now researchers are working on a substance which is created at a room temperature and is even harder than a diamond.
According to Forbes, scientists at North Carolina State University have produced a new phase of solid carbon, Q-carbon. Previously, researchers thought it would be impossible to create diamonds at room temperature and the same atmospheric pressure as the ambient air. The newly created carbon phase is different from the other known solid forms of carbon - graphite and diamond.
"The only place it may be found in the natural world would be possibly in the core of some planets," says NC State's Jay Narayan who is a lead author of three papers on the findings, including one published in Journal of Applied Physics.
He added that Q-carbon is ferromagnetic, which was previously thought to be impossible to create. It is also harder than diamond and when exposed to even a small amount of energy, it glows.
Q-carbon involves coating of a substrate of sapphire, glass or a plastic polymer with a layer of non-crystalline amorphous carbon, as mentioned by UPI. The coated substrate is then highly exposed with a single laser pulse, which lasts for just 200 nanoseconds. It temporarily raises the carbon's temperature to 4,000 Kelvin before quickly cooling with the surrounding air pressure remaining the same.
The substance produced as a result, is a uniquely crystalline material which is harder than a real diamond with a variety of new properties. However, many of the possessed properties are either unstudied or undiscovered.
"Q-carbon's strength and low work-function -- its willingness to release electrons -- make it very promising for developing new electronic display technologies," Narayan said.
As reported by Science Daily, researchers can control the rate of cooling of carbon by using different substrates and changing the duration of the laser pulse. And altering the rate of cooling can enable the scientists to create diamond structures within the Q-carbon.
"We can create diamond nanoneedles or microneedles, nanodots, or large-area diamond films, with applications for drug delivery, industrial processes and for creating high-temperature switches and power electronics," Narayan says. "These diamond objects have a single-crystalline structure, making them stronger than polycrystalline materials. And it is all done at room temperature and at ambient atmosphere -- we're basically using a laser like the ones used for laser eye surgery. So, not only does this allow us to develop new applications, but the process itself is relatively inexpensive."
However, by repeating the laser-pulse/cooling process, researchers convert more of the Q-carbon to diamond. Narayan says, "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," He added, "We know a lot about the diamond, so we can make diamond nanodots. We don't yet know how to make Q-carbon nanodots or microneedles. That's something we're working on."
Two provisional patents have been filed on the Q-carbon and diamond creation techniques, by NC State.