A long-sought-after class of 'superdiamond' carbon-based materials with tunable mechanical and electronic properties predicted and synthesized
A long-sought-after class of "superdiamond" carbon-based materials with tunable mechanical and electronic properties was predicted and synthesized by Carnegie's Li Zhu and Timothy Strobel. Their work is published by Science Advances.
Carnegie's Tim Strobel and Li Zhu led a team that used advanced structure searching tools to predict the first thermodynamically stable carbon-based clathrate and then synthesized the clathrate structure, which is comprised of carbon-boron cages that trap strontium atoms.
Image is courtesy of Tim Strobel
Carbon is the fourth-most-abundant element in the universe and is fundamental to life as we know it. It is unrivaled in its ability to form stable structures, both alone and with other elements.
A material's properties are determined by how its atoms are bonded and the structural arrangements that these bonds create. For carbon-based materials, the type of bonding makes the difference between the hardness of diamond, which has three-dimensional "sp3" bonds, and the softness of graphite, which has two-dimensional "sp2" bonds, for example.
Despite the enormous diversity of carbon compounds, only a handful of three-dimensionally, sp3-bonded carbon-based materials are known, including diamond. The three-dimensional bonding structure makes these materials very attractive for many practical applications due to a range of properties including strength, hardness, and thermal conductivity.
"Aside from diamond and some of its analogs that incorporate additional elements, almost no other extended sp3 carbon materials have been created, despite numerous predictions of potentially synthesizable structures with this kind of bonding," Strobel explained. "Following a chemical principle that indicates adding boron into the structure will enhance its stability, we examined another 3D-bonded class of carbon materials called clathrates, which have a lattice structure of cages that trap other types of atoms or molecules."
Clathrates comprised of other elements and molecules are common and have been synthesized or found in nature. However, carbon-based clathrates have not been synthesized until now, despite long-standing predictions of their existence. Researchers attempted to create them for more than 50 years.
Strobel, Zhu, and their team--Carnegie's Gustav M. Borstad, Hanyu Liu, Piotr A. Gu?ka, Michael Guerette, Juli-Anna Dolyniuk, Yue Meng, and Ronald Cohen, as well as Eran Greenberg and Vitali Prakapenka from the University of Chicago and Brian L. Chaloux and Albert Epshteyn from the U.S. Naval Research Laboratory--approached the problem through a combined computational and experimental approach.
"We used advanced structure searching tools to predict the first thermodynamically stable carbon-based clathrate and then synthesized the clathrate structure, which is comprised of carbon-boron cages that trap strontium atoms, under high-pressure and high-temperature conditions," Zhu said.
The result is a 3D, carbon-based framework with diamond-like bonding that is recoverable to ambient conditions. But unlike diamond, the strontium atoms trapped in the cages make the material metallic--meaning it conducts electricity--with potential for superconductivity at notably high temperature.
What's more, the properties of the clathrate can change depending on the types of guest atoms within the cages.
"The trapped guest atoms interact strongly with the host cages," Strobel remarked. "Depending on the specific guest atoms present, the clathrate can be tuned from a semiconductor to a superconductor, all while maintaining robust, diamond-like bonds. Given the large number of possible substitutions, we envision an entirely new class of carbon-based materials with highly tunable properties."
"For anyone who is into--or whose kids are into--Pokémon, this carbon-based clathrate structure is like the Eevee of materials," joked Zhu. "Depending which element it captures, it has different abilities."
This work was supported by DARPA. Additional support was provided by the Energy Frontier Research in Extreme Environments (EFree) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science; the Polish National Agency for Academic Exchange; the Warsaw University of Technology; a European Research Council Advanced Grant; and ToMCaT.
Computations were conducted using the supercomputer Copper of DoD HPCMP Open Research Systems and the Memex cluster of the Carnegie Institution for Science. Portions of this work were performed at HPCAT and GeoSoilEnviroCARS, Advanced Photon Source, Argonne National Laboratory. HPCAT operations are supported by DOE-NNSA's Office of Experimental Sciences. GeoSoilEnviroCARS is supported by the National Science Foundation - Earth Sciences (EAR - 1634415) and Department of Energy- GeoSciences. The Advanced Photon Source is a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory.
The Carnegie Institution for Science is a private, nonprofit organization headquartered in Washington, D.C., with six research departments throughout the U.S. Since its founding in 1902, the Carnegie Institution has been a pioneering force in basic scientific research. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.
Tim Strobel | EurekAlert!
Printing complex cellulose-based objects
27.03.2020 | ETH Zurich
A key development in the drive for energy-efficient electronics
24.03.2020 | University of Leeds
Together with their colleagues from the University of Würzburg, physicists from the group of Professor Alexander Szameit at the University of Rostock have devised a “funnel” for photons. Their discovery was recently published in the renowned journal Science and holds great promise for novel ultra-sensitive detectors as well as innovative applications in telecommunications and information processing.
The quantum-optical properties of light and its interaction with matter has fascinated the Rostock professor Alexander Szameit since College.
Researchers at the University of Zurich show that different stem cell populations are innervated in distinct ways. Innervation may therefore be crucial for proper tissue regeneration. They also demonstrate that cancer stem cells likewise establish contacts with nerves. Targeting tumour innervation could thus lead to new cancer therapies.
Stem cells can generate a variety of specific tissues and are increasingly used for clinical applications such as the replacement of bone or cartilage....
An international research team led by Kiel University develops an extremely porous material made of "white graphene" for new laser light applications
With a porosity of 99.99 %, it consists practically only of air, making it one of the lightest materials in the world: Aerobornitride is the name of the...
Researchers at Graz University of Technology have developed a framework by which wireless devices with different radio technologies will be able to communicate directly with each other.
Whether networked vehicles that warn of traffic jams in real time, household appliances that can be operated remotely, "wearables" that monitor physical...
Terahertz waves are becoming ever more important in science and technology. They enable us to unravel the properties of future materials, test the quality of...
26.03.2020 | Event News
23.03.2020 | Event News
03.03.2020 | Event News
27.03.2020 | Power and Electrical Engineering
27.03.2020 | Life Sciences
27.03.2020 | Life Sciences