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Diamonds possible without pressure!!
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At Rice University they found a way to cause graphine layers to turn to diamond structures without added pressure.
" Conditions, they learned, need to be just right for a short stack of graphene pancakes to collapse into a diamond matrix – or vice versa – via chemistry.
“A phase diagram shows you which phase dominates the ground state for each pressure and temperature,” Yakobson said. “In the case of diamane, the diagram is unusual because the result also depends on thickness, the number of layers of graphene. So we have a new parameter.”
Hydrogen isn’t the only possible catalyst, he said, but it’s the one they used in their calculations. “When the hydrogen attacks, it takes one electron from a carbon atom in graphene. As a result, a bond is broken and another electron is left hanging on the other side of the graphene layer. It’s now free to connect to a carbon atom on the adjacent sheet with little or no pressure.
“If you have several layers, you get a domino effect, where hydrogen starts a reaction on top and it propagates through the bonded carbon system,” he said. “Once it zips all the way through, the phase transition is complete and the crystal structure is that of diamond.”
More at link:
[link to news.rice.edu]
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