Path to nanodiamond from graphene found

Whereas it could solely take a bit of warmth to show a handled bilayer of the ultrathin materials right into a cubic lattice of diamane, a little bit of stress in simply the fitting place can convert few-layer graphene as nicely.

The in any other case chemically pushed course of is theoretically doable in response to scientists at Rice College, who revealed their most up-to-date ideas on making high-quality diamane — the 2D type of diamond — within the journal Small.

The analysis led by supplies theorist Boris Yakobson and his colleagues at Rice’s Brown College of Engineering suggests a pinpoint of stress on few-layer graphene, the atom-thin type of carbon recognized for its astonishing power, can nucleate a floor chemical response with hydrogen or fluorine.

From there, the diamondlike lattice ought to propagate all through the fabric as atoms of hydrogen or fluorine alight on the highest and backside and covalently bind to the surfaces, prompting carbon-carbon connections between the layers.

The stress utilized to that one spot — as small as a couple of nanometers — is fully pointless for a bilayer however is required and have to be progressively stronger for thicker movies, Yakobson mentioned. Making artificial diamond from bulk graphite at industrial scale requires about 10-15 gigapascals, or 725,000 kilos per sq. inch, of stress.

“Solely on the nanoscale — on this case, at nanometer thickness — does it turns into doable for the floor chemistry alone to alter the thermodynamics of the crystal, shifting the phase-change level from very excessive stress to virtually no stress,” he mentioned.

Single-crystal diamond movie for electronics is very fascinating. The fabric may very well be used as a hardened insulator or as a warmth transducer for cooling nanoelectronics. It may very well be doped to function a large band hole semiconductor in transistors, or as a component in optical functions.

Yakobson and his colleagues developed a section diagram in 2014 to point out how diamane may be thermodynamically possible. There’s nonetheless no straightforward technique to make it, however the brand new work provides a essential element the sooner analysis lacked: a technique to overcome the energetic barrier to nucleation that retains the response in examine.

“To this point solely bilayer graphene has been reproducibly transformed into diamane, however via sheer chemistry,” Yakobson mentioned. “Combining it with a pinch of native stress and the mechanochemistry it triggers looks like a promising path to be tried.”

“In thicker movies, the barrier rises shortly with the variety of layers,” added co-author and former Rice postdoctoral affiliate Pavel Sorokin. “Exterior stress can scale back this barrier, however chemistry and stress should play collectively to ship a 2D diamond.”

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Materials supplied by Rice University. Observe: Content material could also be edited for model and size.