An international team of scientists has challenged nature to make diamonds in a few minutes in a laboratory at room temperature – a process that normally requires billions of years, a lot of pressure and a lot of heat.
The team he leads Australian National University (ANU) and RMIT University have developed two types of diamonds: another type of diamond called Lonsdaleite, which is in the engagement ring and is in place for meteorite impacts such as Canyon Diablo in the United States.
One of the leading researchers, Jodie Bradby, a professor at ANU, said the advances created a similar trick when Superman turned coal into diamonds without using heat rays.
“Natural diamonds are generally formed over billions of years at a depth of 150 km at high pressures and temperatures of more than 1,000 degrees,” he said. CelsiusHe said. Professor Bradby from ANU School of Research Physics.
Former ANU PhD scientist Tom Shiell and the group, now part of the Carnegie Institute for Science, previously created Lonsdaleite in the laboratory only at high temperatures.
This new unexpected discovery shows that both Lonsdaleite and ordinary diamonds can only be formed by applying high pressures at normal room temperatures – the equivalent of 640 African elephants on the tip of a ballet shoe.
“That’s how we apply the bending pressure in the story. In addition to very high pressures, we also allow carbon to encounter something called ‘bending’ or ‘shear’, which is similar to sliding force. We think that this will allow carbon atoms to be replaced to form Lonsdaleite and normal diamonds, ”said Professor Bradby.
Solidarity professor Dougal McCulloch and his team at RMIT used advanced electron microscopy techniques to draw solid and non-woven slices from experimental specimens to create snapshots of how the two types of diamonds came into being.
“Our images show that regular diamonds are formed only in the middle of these Lonsdaleite veins under this new method developed by our institutional team,” said Professor McCulloch.
“It was amazing to see these little ‘rivers’ of lonsdaleite and regular diamonds, and it helps us understand how they can actually come into being.”
Named after Dame Kathleen Lonsdale, the first female crystallogist to be elected to the Royal Society, Lonsdaleite has a crystal structure different from that of a normal diamond. This is projected to be 58 percent more difficult.
“Lonsdaleite has the potential to be used to cut ultra-solid materials in mining areas,” said Professor Bradby.
“It’s a long-term goal to create more than just this rare but super-useful diamond.”
Xingshuo Huang is an ANU doctor scientist working in Professor Bradby’s laboratory.
“Being able to make two types of diamonds at room temperature was exciting to achieve for the first time in our lab,” Huang said.
The team, which includes the University of Sydney and the Oak Ridge National Laboratory in the United States, published the findings in a journal. Small.
Reference: Dougal G. McCulloch, Sherman Wong, Thomas B. Shiell, Bianca Haberl, Brenton A. Cook, Xingshuo Huang, Reinhard Boehler, David R. McKenzie’s “Ultra – Hard Nanocarbon Diamond and Lonsdale’s Room Temperature Formation”. and Jodie E. Bradby, November 4, 2020, Small.
DOI: 10.1002 / smll.202004695