A report claims that scientists have solved a decades-long conundrum and discovered a nearly unbreakable substance that could rival diamond as the hardest material on the planet.
When carbon and nitrogen precursors were subjected to severe heat and pressure, researchers discovered that the emerging materials, known as carbon nitrides, were tougher than cubic boron nitride, the second hardest substance after diamond.
According to specialists, the accomplishment opens the way for multifunctional materials to be employed in industrial applications such as protective coatings for vehicles and rockets, high-endurance cutting tools, solar panels, and photodetectors.
Since the 1980s, when scientists first observed their extraordinary features, such as excellent heat resistance, materials researchers have worked to unleash the promise of carbon nitrides. Despite over three decades of research and numerous attempts to synthesize it, no reliable results have been revealed.
When we discovered the first of these new carbon nitride materials, we were incredulous to have produced materials researchers had been dreaming of for the last three decades. These materials offer a compelling reason to overcome the gap between high-pressure materials synthesis and industrial applications.
Dr Dominique Laniel
Now, an international team of scientists led by academics from the University of Edinburgh’s Centre for Science in Extreme Conditions and experts from the Universities of Bayreuth, Germany, and Linköping, Sweden, has made a breakthrough.
The researchers subjected several kinds of carbon-nitrogen precursors to pressures ranging from 70 to 135 gigapascals (about one million times our atmospheric pressure) while heating them to temperatures exceeding 1500 degrees Celsius.
To identify the atomic arrangement of the compounds under these conditions, the samples were illuminated by an intense X-ray beam at three particle accelerators – the European Synchrotron Research Facility in France, the Deutsches Elektronen-Synchrotron in Germany, and the Advanced Photon Source based in the United States.
Researchers discovered that three carbon nitride compounds were found to have the necessary building blocks for super-hardness.
Surprisingly, when exposed to ambient pressure and temperature, all three compounds retained their diamond-like properties. other calculations and experiments indicate that the new materials have other qualities such as photoluminescence and high energy density, which means that a great quantity of energy may be stored in a little amount of mass.
The potential applications of these ultra-incompressible carbon nitrides, according to researchers, are numerous, potentially putting them as the ultimate engineering materials to rival diamonds. The study, which was published in Advanced Materials, was supported by the UKRI FLF project as well as European research grants.
“When we discovered the first of these new carbon nitride materials, we were incredulous to have produced materials researchers had been dreaming of for the last three decades,” said Dr Dominique Laniel, Future Leaders Fellow, Institute for Condensed Matter Physics and Complex Systems, School of Physics and Astronomy, University of Edinburgh. These materials offer a compelling reason to overcome the gap between high-pressure materials synthesis and industrial applications.”
“These materials are not only outstanding in their multi-functionality, but show that technologically relevant phases can be recovered from a synthesis pressure equivalent to the conditions found thousands of kilometers in the Earth’s interior,” said Dr Florian Trybel, Assistant Professor, Department of Physics, Chemistry, and Biology, University of Linköping. “We strongly believe this collaborative research will open up new possibilities for the field.”
