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Chepkasov IV, Radina AD, Kvashnin AG. Structure-driven tuning of catalytic properties of core-shell nanostructures. Nanoscale 2024; 16:5870-5892. [PMID: 38450538 DOI: 10.1039/d3nr06194a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
The annual increase in demand for renewable energy is driving the development of catalysis-based technologies that generate, store and convert clean energy by splitting and forming chemical bonds. Thanks to efforts over the last two decades, great progress has been made in the use of core-shell nanostructures to improve the performance of metallic catalysts. The successful preparation and application of a large number of bimetallic core-shell nanocrystals demonstrates the wide range of possibilities they offer and suggests further advances in this field. Here, we have reviewed recent advances in the synthesis and study of core-shell nanostructures that are promising for catalysis. Particular attention has been paid to the structural tuning of the catalytic properties of core-shell nanostructures and to theoretical methods capable of describing their catalytic properties in order to efficiently search for new catalysts with desired properties. We have also identified the most promising areas of research in this field, in terms of experimental and theoretical studies, and in terms of promising materials to be studied.
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Affiliation(s)
- Ilya V Chepkasov
- Skolkovo Institute of Science and Technology, 121205, Bolshoi Blv. 30, Building 1, Moscow, Russia.
| | - Aleksandra D Radina
- Skolkovo Institute of Science and Technology, 121205, Bolshoi Blv. 30, Building 1, Moscow, Russia.
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, 121205, Bolshoi Blv. 30, Building 1, Moscow, Russia.
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2
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Chepkasov IV, Zamulin IS, Baidyshev VS, Kvashnin AG. Tuning the surface properties of AuPd nanoparticles for adsorption of O and CO. Phys Chem Chem Phys 2023. [PMID: 38037396 DOI: 10.1039/d3cp03213b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Bimetallic nanoparticles are attracting increasing attention as effective catalysts because they can exhibit higher efficiencies than their monometallic counterparts. Recent studies show that PdAu nanoparticles can exhibit truly impressive catalytic activity, due to the synergistic effect of their properties. However, fine-tuning the catalytic activity requires an understanding of the full picture of the processes taking place in bimetallic particles of different compositions and structures. Here we study the influence of the structure and composition of PdAu nanoparticles on their electronic properties, charge distribution and adsorption properties (CO and O) using ab initio calculations. Two types of nanoparticles were considered: core-shell (Pd@Au and Au@Pd) and bimetallic alloy (Au-Pd) with an average diameter of 2 nm (321 atoms), having either fcc, icosahedral or amorphous structures. The results obtained on surface charges show the possibility of fine-tuning the surface properties of nanoparticles by modifying their atomic structure and composition. In addition, the adsorption of O and CO on the surface of PdAu nanoparticles with fcc structure has been studied. The obtained adsorption data correlate with the surface charge redistribution and the d-band center. The results of this study thus open up great prospects for tuning the catalytic properties of nanocatalysts by modifying their local atomic environment.
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Affiliation(s)
- Ilya V Chepkasov
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russian Federation.
- Katanov Khakas State University, 90 Lenin pr., 655017, Abakan, Russian Federation
| | - Ivan S Zamulin
- Katanov Khakas State University, 90 Lenin pr., 655017, Abakan, Russian Federation
| | - Viktor S Baidyshev
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russian Federation.
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russian Federation.
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3
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Troyan IA, Semenok DV, Ivanova AG, Sadakov AV, Zhou D, Kvashnin AG, Kruglov IA, Sobolevskiy OA, Lyubutina MV, Perekalin DS, Helm T, Tozer SW, Bykov M, Goncharov AF, Pudalov VM, Lyubutin IS. Non-Fermi-Liquid Behavior of Superconducting SnH 4. Adv Sci (Weinh) 2023; 10:e2303622. [PMID: 37626451 PMCID: PMC10602579 DOI: 10.1002/advs.202303622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/18/2023] [Indexed: 08/27/2023]
Abstract
The chemical interaction of Sn with H2 by X-ray diffraction methods at pressures of 180-210 GPa is studied. A previously unknown tetrahydride SnH4 with a cubic structure (fcc) exhibiting superconducting properties below TC = 72 K is obtained; the formation of a high molecular C2/m-SnH14 superhydride and several lower hydrides, fcc SnH2 , and C2-Sn12 H18 , is also detected. The temperature dependence of critical current density JC (T) in SnH4 yields the superconducting gap 2Δ(0) = 21.6 meV at 180 GPa. SnH4 has unusual behavior in strong magnetic fields: B,T-linear dependences of magnetoresistance and the upper critical magnetic field BC2 (T) ∝ (TC - T). The latter contradicts the Wertheimer-Helfand-Hohenberg model developed for conventional superconductors. Along with this, the temperature dependence of electrical resistance of fcc SnH4 in non-superconducting state exhibits a deviation from what is expected for phonon-mediated scattering described by the Bloch-Grüneisen model and is beyond the framework of the Fermi liquid theory. Such anomalies occur for many superhydrides, making them much closer to cuprates than previously believed.
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Affiliation(s)
- Ivan A. Troyan
- Shubnikov Institute of CrystallographyFederal Scientific Research Center Crystallography and PhotonicsRussian Academy of Sciences59 Leninsky ProspektMoscow119333Russia
| | - Dmitrii V. Semenok
- Center for High Pressure Science and Technology Advanced Research (HPSTAR)Beijing100193China
| | - Anna G. Ivanova
- Shubnikov Institute of CrystallographyFederal Scientific Research Center Crystallography and PhotonicsRussian Academy of Sciences59 Leninsky ProspektMoscow119333Russia
| | - Andrey V. Sadakov
- V. L. Ginzburg Center for High‐Temperature Superconductivity and Quantum Materials P. N. Lebedev Physical InstituteRussian Academy of SciencesMoscow119991Russia
| | - Di Zhou
- Center for High Pressure Science and Technology Advanced Research (HPSTAR)Beijing100193China
| | - Alexander G. Kvashnin
- Skolkovo Institute of Science and TechnologyBolshoy Boulevard, 30/1Moscow121205Russia
| | - Ivan A. Kruglov
- Center for Fundamental and Applied ResearchDukhov Research Institute of Automatics (VNIIA)st. Sushchevskaya, 22Moscow127055Russia
- Laboratory of Computational Materials DiscoveryMoscow Institute of Physics and Technology9 Institutsky LaneDolgoprudny141700Russia
| | - Oleg A. Sobolevskiy
- V. L. Ginzburg Center for High‐Temperature Superconductivity and Quantum Materials P. N. Lebedev Physical InstituteRussian Academy of SciencesMoscow119991Russia
| | - Marianna V. Lyubutina
- Shubnikov Institute of CrystallographyFederal Scientific Research Center Crystallography and PhotonicsRussian Academy of Sciences59 Leninsky ProspektMoscow119333Russia
| | - Dmitry S. Perekalin
- A.N. Nesmeyanov Institute of Organoelement CompoundsRussian Academy of Sciences28 Vavilova str.Moscow119334Russia
| | - Toni Helm
- Hochfeld‐Magnetlabor Dresden (HLD‐EMFL) and Würzburg‐Dresden Cluster of ExcellenceHelmholtz‐Zentrum Dresden‐Rossendorf (HZDR)01328DresdenGermany
| | - Stanley W. Tozer
- National High Magnetic Field LaboratoryFlorida State UniversityTallahasseeFlorida32310USA
| | - Maxim Bykov
- Institute of Inorganic ChemistryUniversity of Cologne50939CologneGermany
| | - Alexander F. Goncharov
- Earth and Planets LaboratoryCarnegie Institution for Science5241 Broad Branch Road NWWashingtonDC20015USA
| | - Vladimir M. Pudalov
- V. L. Ginzburg Center for High‐Temperature Superconductivity and Quantum Materials P. N. Lebedev Physical InstituteRussian Academy of SciencesMoscow119991Russia
- HSE Tikhonov Moscow Institute of Electronics and Mathematics National Research University Higher School of Economics20 Myasnitskaya ulitsaMoscow101000Russia
| | - Igor S. Lyubutin
- Shubnikov Institute of CrystallographyFederal Scientific Research Center Crystallography and PhotonicsRussian Academy of Sciences59 Leninsky ProspektMoscow119333Russia
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4
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Tantardini C, Kvashnin AG, Azizi M, Gonze X, Gatti C, Altalhi T, Yakobson BI. Electronic Properties of Functionalized Diamanes for Field-Emission Displays. ACS Appl Mater Interfaces 2023; 15:16317-16326. [PMID: 36926821 PMCID: PMC10064316 DOI: 10.1021/acsami.3c01536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/07/2023] [Indexed: 06/18/2023]
Abstract
Ultrathin diamond films, or diamanes, are promising quasi-2D materials that are characterized by high stiffness, extreme wear resistance, high thermal conductivity, and chemical stability. Surface functionalization of multilayer graphene with different stackings of layers could be an interesting opportunity to induce proper electronic properties into diamanes. Combination of these electronic properties together with extraordinary mechanical ones will lead to their applications as field-emission displays substituting original devices with light-emitting diodes or organic light-emitting diodes. In the present study, we focus on the electronic properties of fluorinated and hydrogenated diamanes with (111), (110), (0001), (101̅0), and (2̅110) crystallographic orientations of surfaces of various thicknesses by using first-principles calculations and Bader analysis of electron density. We see that fluorine induces an occupied surface electronic state, while hydrogen modifies the occupied bulk state and also induces unoccupied surface states. Furthermore, a lower number of layers is necessary for hydrogenated diamanes to achieve the convergence of the work function in comparison with fluorinated diamanes, with the exception of fluorinated (110) and (2̅110) films that achieve rapid convergence and have the same behavior as other hydrogenated surfaces. This induces a modification of the work function with an increase of the number of layers that makes hydrogenated (2̅110) diamanes the most suitable surface for field-emission displays, better than the fluorinated counterparts. In addition, a quasi-quantitative descriptor of surface dipole moment based on the Tantardini-Oganov electronegativity scale is introduced as the average of bond dipole moments between the surface atoms. This new fundamental descriptor is capable of predicting a priori the bond dipole moment and may be considered as a new useful feature for crystal structure prediction based on artificial intelligence.
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Affiliation(s)
- Christian Tantardini
- Hylleraas
Center, Department of Chemistry, UiT The
Arctic University of Norway, P.O. Box 6050 Langnes, N-9037 Tromsø, Norway
- Department
of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
- Institute
of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk 630128, Russian Federation
| | - Alexander G. Kvashnin
- Skolkovo
Institute of Science and Technology, Bolshoi Boulevard 30, Building 1, Moscow 121205, Russian Federation
| | - Maryam Azizi
- Université
catholique de Louvain, Place de l’Université 1, Ottignies-Louvain-la-Neuve 1348, Belgium
| | - Xavier Gonze
- Université
catholique de Louvain, Place de l’Université 1, Ottignies-Louvain-la-Neuve 1348, Belgium
| | - Carlo Gatti
- SCITEC
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Istituto di Scienze e Tecnologie Chimiche “Giulio Natta”, CNR - Consiglio Nazionale delle Ricerche, sezione di via Golgi, 19, Milan 20133, Italy
| | - Tariq Altalhi
- Chemistry
Department, Taif University, Al Hawiyah, Taif 26571, Saudi Arabia
| | - Boris I. Yakobson
- Department
of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
- Chemistry
Department, Taif University, Al Hawiyah, Taif 26571, Saudi Arabia
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5
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Semenok DV, Troyan IA, Sadakov AV, Zhou D, Galasso M, Kvashnin AG, Ivanova AG, Kruglov IA, Bykov AA, Terent'ev KY, Cherepakhin AV, Sobolevskiy OA, Pervakov KS, Seregin AY, Helm T, Förster T, Grockowiak AD, Tozer SW, Nakamoto Y, Shimizu K, Pudalov VM, Lyubutin IS, Oganov AR. Effect of Magnetic Impurities on Superconductivity in LaH 10. Adv Mater 2022; 34:e2204038. [PMID: 35829689 DOI: 10.1002/adma.202204038] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/17/2022] [Indexed: 06/15/2023]
Abstract
Polyhydrides are a novel class of superconducting materials with extremely high critical parameters, which is very promising for sensor applications. On the other hand, a complete experimental study of the best so far known superconductor, lanthanum superhydride LaH10 , encounters a serious complication because of the large upper critical magnetic field HC2 (0), exceeding 120-160 T. It is found that partial replacement of La atoms by magnetic Nd atoms results in significant suppression of superconductivity in LaH10 : each at% of Nd causes a decrease in TC by 10-11 K, helping to control the critical parameters of this compound. Strong pulsed magnetic fields up to 68 T are used to study the Hall effect, magnetoresistance, and the magnetic phase diagram of ternary metal polyhydrides for the first time. Surprisingly, (La,Nd)H10 demonstrates completely linear HC2 (T) ∝ |T - TC |, which calls into question the applicability of the Werthamer-Helfand-Hohenberg model for polyhydrides. The suppression of superconductivity in LaH10 by magnetic Nd atoms and the robustness of TC with respect to nonmagnetic impurities (e.g., Y, Al, C) under Anderson's theorem gives new experimental evidence of the isotropic (s-wave) character of conventional electron-phonon pairing in lanthanum decahydride.
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Affiliation(s)
- Dmitrii V Semenok
- Materials Discovery Laboratory, Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Ivan A Troyan
- Shubnikov Institute of Crystallography, Federal Scientific Research Center "Crystallography and Photonics", Russian Academy of Sciences, 59 Leninsky Prospekt, Moscow, 119333, Russia
| | - Andrey V Sadakov
- V.L. Ginzburg Center for High-Temperature Superconductivity and Quantum Materials, P. N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Di Zhou
- Materials Discovery Laboratory, Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Michele Galasso
- Materials Discovery Laboratory, Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Alexander G Kvashnin
- Materials Discovery Laboratory, Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Anna G Ivanova
- Shubnikov Institute of Crystallography, Federal Scientific Research Center "Crystallography and Photonics", Russian Academy of Sciences, 59 Leninsky Prospekt, Moscow, 119333, Russia
| | - Ivan A Kruglov
- Center for Fundamental and Applied Research, Dukhov Research Institute of Automatics (VNIIA), st. Sushchevskaya, 22, Moscow, 127055, Russia
- Laboratory of Computational Materials Discovery, Moscow Institute of Physics and Technology, 9 Institutsky Lane, Dolgoprudny, 141700, Russia
| | - Alexey A Bykov
- Crystal Physics Laboratory, NRC "Kurchatov Institute" PNPI, 1, mkr. Orlova roshcha, Gatchina, 188300, Russia
| | - Konstantin Y Terent'ev
- Kirensky Institute of Physics, Siberian Branch of the Russian Academy of Sciences, Akademgorodok 50, bld. 38, Krasnoyarsk, 660036, Russia
| | - Alexander V Cherepakhin
- Kirensky Institute of Physics, Siberian Branch of the Russian Academy of Sciences, Akademgorodok 50, bld. 38, Krasnoyarsk, 660036, Russia
| | - Oleg A Sobolevskiy
- V.L. Ginzburg Center for High-Temperature Superconductivity and Quantum Materials, P. N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Kirill S Pervakov
- V.L. Ginzburg Center for High-Temperature Superconductivity and Quantum Materials, P. N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Alexey Yu Seregin
- Shubnikov Institute of Crystallography, Federal Scientific Research Center "Crystallography and Photonics", Russian Academy of Sciences, 59 Leninsky Prospekt, Moscow, 119333, Russia
- Synchrotron radiation source "KISI-Kurchatov", National Research Center "Kurchatov Institute", Moscow, 123182, Russia
| | - Toni Helm
- Hochfeld-Magnetlabor Dresden (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328, Dresden, Germany
| | - Tobias Förster
- Hochfeld-Magnetlabor Dresden (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328, Dresden, Germany
| | - Audrey D Grockowiak
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310, USA
- Brazilian Synchrotron Light Laboratory (LNLS/Sirius), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, 13083-100, Brazil
| | - Stanley W Tozer
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310, USA
| | - Yuki Nakamoto
- KYOKUGEN, Graduate School of Engineering Science, Osaka University, Machikaneyamacho 1-3, Toyonaka, Osaka, 560-8531, Japan
| | - Katsuya Shimizu
- KYOKUGEN, Graduate School of Engineering Science, Osaka University, Machikaneyamacho 1-3, Toyonaka, Osaka, 560-8531, Japan
| | - Vladimir M Pudalov
- V.L. Ginzburg Center for High-Temperature Superconductivity and Quantum Materials, P. N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, 119991, Russia
- HSE Tikhonov Moscow Institute of Electronics and Mathematics, National Research University Higher School of Economics, 20 Myasnitskaya ulitsa, Moscow, 101000, Russia
| | - Igor S Lyubutin
- Shubnikov Institute of Crystallography, Federal Scientific Research Center "Crystallography and Photonics", Russian Academy of Sciences, 59 Leninsky Prospekt, Moscow, 119333, Russia
| | - Artem R Oganov
- Materials Discovery Laboratory, Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
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Chowdhury S, Demin VA, Chernozatonskii LA, Kvashnin AG. Ultra-Low Thermal Conductivity of Moiré Diamanes. Membranes (Basel) 2022; 12:925. [PMID: 36295684 PMCID: PMC9607344 DOI: 10.3390/membranes12100925] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/13/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Ultra-thin diamond membranes, diamanes, are one of the most intriguing quasi-2D films, combining unique mechanical, electronic and optical properties. At present, diamanes have been obtained from bi- or few-layer graphene in AA- and AB-stacking by full hydrogenation or fluorination. Here, we study the thermal conductivity of diamanes obtained from bi-layer graphene with twist angle θ between layers forming a Moiré pattern. The combination of DFT calculations and machine learning interatomic potentials makes it possible to perform calculations of the lattice thermal conductivity of such diamanes with twist angles θ of 13.2∘, 21.8∘ and 27.8∘ using the solution of the phonon Boltzmann transport equation. Obtained results show that Moiré diamanes exhibit a wide variety of thermal properties depending on the twist angle, namely a sharp decrease in thermal conductivity from high for "untwisted" diamanes to ultra-low values when the twist angle tends to 30∘, especially for hydrogenated Moiré diamanes. This effect is associated with high anharmonicity and scattering of phonons related to a strong symmetry breaking of the atomic structure of Moiré diamanes compared with untwisted ones.
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Affiliation(s)
- Suman Chowdhury
- Department of Physics, Shiv Nadar University, Gautam Buddha Nagar, Greater Noida 201314, Uttar Pradesh, India
| | - Victor A. Demin
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, 119334 Moscow, Russia
| | | | - Alexander G. Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Bolshoi Blv. 30, Building 1, 121205 Moscow, Russia
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7
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Semenok DV, Chen W, Huang X, Zhou D, Kruglov IA, Mazitov AB, Galasso M, Tantardini C, Gonze X, Kvashnin AG, Oganov AR, Cui T. Sr-Doped Superionic Hydrogen Glass: Synthesis and Properties of SrH 22. Adv Mater 2022; 34:e2200924. [PMID: 35451134 DOI: 10.1002/adma.202200924] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Recently, several research groups announced reaching the point of metallization of hydrogen above 400 GPa. Despite notable progress, detecting superconductivity in compressed hydrogen remains an unsolved problem. Following the mainstream of extensive investigations of compressed metal polyhydrides, here small doping of molecular hydrogen by strontium is demonstrated to lead to a dramatic reduction in the metallization pressure to ≈200 GPa. Studying the high-pressure chemistry of the Sr-H system, the formation of several new phases is observed: C2/m-Sr3 H13 , pseudocubic SrH6 , SrH9 with cubic F 4 ¯ 3 m $F\bar{4}3m$ -Sr sublattice, and pseudo tetragonal superionic P1-SrH22 , the metal hydride with the highest hydrogen content (96 at%) discovered so far. High diffusion coefficients of hydrogen in the latter phase DH = 0.2-2.1 × 10-9 m2 s-1 indicate an amorphous state of the H-sublattice, whereas the strontium sublattice remains solid. Unlike Ca and Y, strontium forms molecular semiconducting polyhydrides, whereas calcium and yttrium polyhydrides are high-TC superconductors with an atomic H sublattice. The discovered SrH22 , a kind of hydrogen sponge, opens a new class of materials with ultrahigh content of hydrogen.
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Affiliation(s)
- Dmitrii V Semenok
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Wuhao Chen
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
| | - Xiaoli Huang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
| | - Di Zhou
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Ivan A Kruglov
- Dukhov Research Institute of Automatics (VNIIA), Moscow, 127055, Russia
- Moscow Institute of Physics and Technology, 9 Institutsky Lane, Dolgoprudny, 141700, Russia
| | - Arslan B Mazitov
- Dukhov Research Institute of Automatics (VNIIA), Moscow, 127055, Russia
- Moscow Institute of Physics and Technology, 9 Institutsky Lane, Dolgoprudny, 141700, Russia
| | - Michele Galasso
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Christian Tantardini
- UiT The Arctic University of Norway, PO Box 6050 Langnes, Troms, N-9037, Norway
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk, 630128, Russian Federation
| | - Xavier Gonze
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
- European Theoretical Spectroscopy Facility, Institute of Condensed Matter and Nanosciences, Université Catholique de Louvain, Chemin des étoiles 8, bte L07.03.01, Louvain-la-Neuve, B-1348, Belgium
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard, 30/1, Moscow, 121205, Russia
| | - Tian Cui
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
- School of Physical Science and Technology, Ningbo University, Ningbo, 315211, China
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8
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Pak AY, Rybkovskiy DV, Vassilyeva YZ, Kolobova EN, Filimonenko AV, Kvashnin AG. Efficient Synthesis of WB 5-x-WB 2 Powders with Selectivity for WB 5-x Content. Inorg Chem 2022; 61:6773-6784. [PMID: 35476453 DOI: 10.1021/acs.inorgchem.1c03880] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We proposed an efficient method toward the synthesis of higher tungsten boride WB5-x in the vacuumless direct current atmospheric arc discharge plasma. The crystal structure of the synthesized samples of boron-rich tungsten boride was determined using computational techniques, showing a two-phase system. The ab initio calculations of the energies of various structures with similar X-ray diffraction (XRD) patterns allowed us to determine the composition of the formed higher tungsten boride. We determined the optimal parameters of synthesis to obtain samples with 61.5% WB5-x by volume. The transmission electron microscopy measurements showed that 90% of the particles have sizes of up to 100 nm, whereas the rest of them may have sizes from 125 to 225 nm. Our study shows the possibility of using the proposed vacuumless method as an efficient and inexpensive way to synthesize superhard WB5-x without employing resource-consuming vacuum techniques.
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Affiliation(s)
- Alexander Ya Pak
- National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk 634050, Russia
| | - Dmitry V Rybkovskiy
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russia
| | - Yuliya Z Vassilyeva
- National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk 634050, Russia
| | - Ekaterina N Kolobova
- National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk 634050, Russia
| | | | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russia
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9
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Chepkasov IV, Sukhanova EV, Kvashnin AG, Zakaryan HA, Aghamalyan MA, Mamasakhlisov YS, Manakhov AM, Popov ZI, Kvashnin DG. Computational Design of Gas Sensors Based on V 3S 4 Monolayer. Nanomaterials (Basel) 2022; 12:nano12050774. [PMID: 35269262 PMCID: PMC8912300 DOI: 10.3390/nano12050774] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 02/17/2022] [Accepted: 02/22/2022] [Indexed: 02/04/2023]
Abstract
Novel magnetic gas sensors are characterized by extremely high efficiency and low energy consumption, therefore, a search for a two-dimensional material suitable for room temperature magnetic gas sensors is a critical task for modern materials scientists. Here, we computationally discovered a novel ultrathin two-dimensional antiferromagnet V3S4, which, in addition to stability and remarkable electronic properties, demonstrates a great potential to be applied in magnetic gas sensing devices. Quantum-mechanical calculations within the DFT + U approach show the antiferromagnetic ground state of V3S4, which exhibits semiconducting electronic properties with a band gap of 0.36 eV. A study of electronic and magnetic response to the adsorption of various gas agents showed pronounced changes in properties with respect to the adsorption of NH3, NO2, O2, and NO molecules on the surface. The calculated energies of adsorption of these molecules were −1.25, −0.91, −0.59, and −0.93 eV, respectively. Obtained results showed the prospective for V3S4 to be used as effective sensing materials to detect NO2 and NO, for their capture, and for catalytic applications in which it is required to lower the dissociation energy of O2, for example, in oxygen reduction reactions. The sensing and reducing of NO2 and NO have great importance for improving environmental protection and sustainable development.
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Affiliation(s)
- Ilya V. Chepkasov
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, 121205 Moscow, Russia;
| | - Ekaterina V. Sukhanova
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, 119334 Moscow, Russia; (E.V.S.); (Z.I.P.); (D.G.K.)
| | - Alexander G. Kvashnin
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, 121205 Moscow, Russia;
- Correspondence:
| | - Hayk A. Zakaryan
- Computational Materials Science Laboratory at the Center of Semiconductor Devices and Nanotechnology, Yerevan State University, 1 Alex Manoogian St., Yerevan 0025, Armenia; (H.A.Z.); (M.A.A.)
| | - Misha A. Aghamalyan
- Computational Materials Science Laboratory at the Center of Semiconductor Devices and Nanotechnology, Yerevan State University, 1 Alex Manoogian St., Yerevan 0025, Armenia; (H.A.Z.); (M.A.A.)
| | - Yevgeni Sh. Mamasakhlisov
- Department of Molecular Physics, Yerevan State University, 1 Alex Manoogian St., Yerevan 0025, Armenia;
- Department of Materials Technology and Structure of Electronic Technique, Russian-Armenian University, 123 Hovsep Emin St., Yerevan 0051, Armenia
| | - Anton M. Manakhov
- Aramco Innovations LLC, Aramco Research Center, 119234 Moscow, Russia;
| | - Zakhar I. Popov
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, 119334 Moscow, Russia; (E.V.S.); (Z.I.P.); (D.G.K.)
| | - Dmitry G. Kvashnin
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, 119334 Moscow, Russia; (E.V.S.); (Z.I.P.); (D.G.K.)
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10
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Podryabinkin EV, Kvashnin AG, Asgarpour M, Maslenikov II, Ovsyannikov DA, Sorokin PB, Popov MY, Shapeev AV. Nanohardness from First Principles with Active Learning on Atomic Environments. J Chem Theory Comput 2022; 18:1109-1121. [PMID: 34990122 DOI: 10.1021/acs.jctc.1c00783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We propose a methodology for the calculation of nanohardness by atomistic simulations of nanoindentation. The methodology is enabled by machine-learning interatomic potentials fitted on the fly to quantum-mechanical calculations of local fragments of the large nanoindentation simulation. We test our methodology by calculating nanohardness, as a function of load and crystallographic orientation of the surface, of diamond, AlN, SiC, BC2N, and Si and comparing it to the calibrated values of the macro- and microhardness. The observed agreement between the computational and experimental results from the literature provides evidence that our method has sufficient predictive power to open up the possibility of designing materials with exceptional hardness directly from first principles. It will be especially valuable at the nanoscale where the experimental measurements are difficult, while empirical models fitted to macrohardness are, as a rule, inapplicable.
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Affiliation(s)
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, 3 Nobel Street, Moscow 121025, Russia
| | - Milad Asgarpour
- Skolkovo Institute of Science and Technology, 3 Nobel Street, Moscow 121025, Russia.,University of Limerick, Limerick V94 T9PX, Ireland
| | - Igor I Maslenikov
- Technological Institute of Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 108840, Russia
| | - Danila A Ovsyannikov
- Technological Institute of Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 108840, Russia
| | - Pavel B Sorokin
- Technological Institute of Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 108840, Russia.,National University of Science and Technology "MISiS", Leninskiy Prospekt 4, Moscow 119049, Russia
| | - Mikhail Yu Popov
- Technological Institute of Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 108840, Russia.,National University of Science and Technology "MISiS", Leninskiy Prospekt 4, Moscow 119049, Russia
| | - Alexander V Shapeev
- Skolkovo Institute of Science and Technology, 3 Nobel Street, Moscow 121025, Russia
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11
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Popov ZI, Tikhomirova KA, Demin VA, Chowdhury S, Oganov AR, Kvashnin AG, Kvashnin DG. Novel two-dimensional boron oxynitride predicted using the USPEX evolutionary algorithm. Phys Chem Chem Phys 2021; 23:26178-26184. [PMID: 34807199 DOI: 10.1039/d1cp03754d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Oxidation is a unique process that significantly changes the structure and properties of a material. Doping of h-BN by oxygen is a hot topic in material science leading to the possibility of synthesis of novel 2D structures with customized electronic properties. It is still unclear how the atomic structure changes in the presence of external atoms during the oxidation of h-BN. We predict novel two-dimensional (2D) arrangements of boron oxynitride using the evolutionary algorithm of crystal structure prediction USPEX. All considered structures demonstrate semiconducting properties with a reduced bandgap compared with h-BN. Both molecular dynamics and phonon calculations show the dynamical stability of the new 2D B5N3O2 phase, and our calculations demonstrate that it can form a bulk layered structure with an interlayer distance larger than that of pure h-BN. The optical characterization shows a redshift of the absorption spectrum compared with pure h-BN. Incorporation of oxygen into the structure of 2D BN during synthesis or oxidation can dramatically change the covalent network of h-BN while preserving its two-dimensionality and flatness, following the presence of local dipole moments which could improve the piezoelectric properties.
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Affiliation(s)
- Zakhar I Popov
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, Moscow 119334, Russian Federation.
| | - Kseniya A Tikhomirova
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, Moscow 119334, Russian Federation. .,Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121025, Russian Federation
| | - Victor A Demin
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, Moscow 119334, Russian Federation.
| | - Suman Chowdhury
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121025, Russian Federation
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121025, Russian Federation
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121025, Russian Federation
| | - Dmitry G Kvashnin
- Emanuel Institute of Biochemical Physics RAS, 4 Kosygin Street, Moscow 119334, Russian Federation. .,Moscow Institute of Physics and Technology, Institutsky Pereulok, Dolgoprudny 141701, Moscow Region, Russian Federation.
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12
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Kvashnin AG, Kruglov IA, Semenok DV, Oganov AR. Computational search for new high- T
c superconductors based on lanthanoid and actinoid hydrides at moderate pressures. Acta Crystallogr A Found Adv 2021. [DOI: 10.1107/s0108767321096021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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13
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Tantardini C, Kvashnin AG, Gatti C, Yakobson BI, Gonze X. Computational Modeling of 2D Materials under High Pressure and Their Chemical Bonding: Silicene as Possible Field-Effect Transistor. ACS Nano 2021; 15:6861-6871. [PMID: 33730478 DOI: 10.1021/acsnano.0c10609] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
To study the possibility for silicene to be employed as a field-effect transistor (FET) pressure sensor, we explore the chemistry of monolayer and multilayered silicene focusing on the change in hybridization under pressure. Ab initio computations show that the effect of pressure depends greatly on the thickness of the silicene film, but also reveals the influence of real experimental conditions, where the pressure is not hydrostatic. For this purpose, we introduce anisotropic strain states. With pure uniaxial stress applied to silicene layers, a path for sp3 silicon to sp3d silicon is found, unlike with pure hydrostatic pressure. Even with mixed-mode stress (in-plane pressure half of the out-of-plane one), we find no such path. In addition to introducing our theoretical approach to study 2D materials, we show how the hybridization change of silicene under pressure makes it a good FET pressure sensor.
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Affiliation(s)
- Christian Tantardini
- Skolkovo Institute of Science and Technology, 3 Nobel Street, 121025 Moscow, Russian Federation
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, 630128 Novosibirsk, Russian Federation
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, 3 Nobel Street, 121025 Moscow, Russian Federation
| | - Carlo Gatti
- CNR - Consiglio Nazionale delle Ricerche, SCITEC - Istituto di Scienze e Tecnologie Chimiche "Giulio Natta", Sezione di via Golgi, 19, 20133 Milan, Italy
| | - Boris I Yakobson
- Department of Chemistry, Taif University, Al Hawiyah, Taif 26571, Saudi Arabia
- Department of Materials Science and NanoEngineering and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, United States
| | - Xavier Gonze
- Skolkovo Institute of Science and Technology, 3 Nobel Street, 121025 Moscow, Russian Federation
- Université Catholique de Louvain, Place de l'Université 1, 1348, Ottignies-Louvain-la-Neuve, Belgium
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14
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Troyan IA, Semenok DV, Kvashnin AG, Sadakov AV, Sobolevskiy OA, Pudalov VM, Ivanova AG, Prakapenka VB, Greenberg E, Gavriliuk AG, Lyubutin IS, Struzhkin VV, Bergara A, Errea I, Bianco R, Calandra M, Mauri F, Monacelli L, Akashi R, Oganov AR. Anomalous High-Temperature Superconductivity in YH 6. Adv Mater 2021; 33:e2006832. [PMID: 33751670 DOI: 10.1002/adma.202006832] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/25/2020] [Indexed: 06/12/2023]
Abstract
Pressure-stabilized hydrides are a new rapidly growing class of high-temperature superconductors, which is believed to be described within the conventional phonon-mediated mechanism of coupling. Here, the synthesis of one of the best-known high-TC superconductors-yttrium hexahydride I m 3 ¯ m -YH6 is reported, which displays a superconducting transition at ≈224 K at 166 GPa. The extrapolated upper critical magnetic field Bc2 (0) of YH6 is surprisingly high: 116-158 T, which is 2-2.5 times larger than the calculated value. A pronounced shift of TC in yttrium deuteride YD6 with the isotope coefficient 0.4 supports the phonon-assisted superconductivity. Current-voltage measurements show that the critical current IC and its density JC may exceed 1.75 A and 3500 A mm-2 at 4 K, respectively, which is higher than that of the commercial superconductors, such as NbTi and YBCO. The results of superconducting density functional theory (SCDFT) and anharmonic calculations, together with anomalously high critical magnetic field, suggest notable departures of the superconducting properties from the conventional Migdal-Eliashberg and Bardeen-Cooper-Schrieffer theories, and presence of an additional mechanism of superconductivity.
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Affiliation(s)
- Ivan A Troyan
- Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii Prospect, Moscow, 119333, Russia
| | - Dmitrii V Semenok
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121025, Russia
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121025, Russia
| | - Andrey V Sadakov
- P.N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Oleg A Sobolevskiy
- P.N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Vladimir M Pudalov
- P.N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow, 119991, Russia
- National Research University, Higher School of Economics, Moscow, 101000, Russia
| | - Anna G Ivanova
- Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii Prospect, Moscow, 119333, Russia
| | - Vitali B Prakapenka
- Center for Advanced Radiation Sources, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL, 60637, USA
| | - Eran Greenberg
- Center for Advanced Radiation Sources, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL, 60637, USA
| | - Alexander G Gavriliuk
- Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii Prospect, Moscow, 119333, Russia
- Institute for Nuclear Research, Russian Academy of Sciences, Fizicheskaya str. 27, Troitsk, Moscow, 108840, Russia
| | - Igor S Lyubutin
- Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii Prospect, Moscow, 119333, Russia
| | - Viktor V Struzhkin
- Center for High Pressure Science and Technology Advanced Research, Shanghai, 201203, China
| | - Aitor Bergara
- Centro de Física de Materiales CFM, CSIC-UPV/EHU, Paseo Manuel de Lardizabal 5, Basque Country, Donostia, 20018, Spain
- Departamento de Física de la Materia Condensada, University of the Basque Country (UPV/EHU), Basque Country, Bilbao, 48080, Spain
- Donostia International Physics Center (DIPC), Manuel Lardizabal pasealekua 4, Basque Country, Donostia, 20018, Spain
| | - Ion Errea
- Centro de Física de Materiales CFM, CSIC-UPV/EHU, Paseo Manuel de Lardizabal 5, Basque Country, Donostia, 20018, Spain
- Donostia International Physics Center (DIPC), Manuel Lardizabal pasealekua 4, Basque Country, Donostia, 20018, Spain
- Fisika Aplikatua 1 Saila, University of the Basque Country (UPV/EHU), Europa plaza 1, Donostia, 20018, Spain
| | - Raffaello Bianco
- Centro de Física de Materiales CFM, CSIC-UPV/EHU, Paseo Manuel de Lardizabal 5, Basque Country, Donostia, 20018, Spain
| | - Matteo Calandra
- Departimento di Fisica, Università di Trento, Via Sommarive 14, Povo, 38123, Italy
- Sorbonne Université, CNRS, Institut des Nanosciences de Paris, UMR7588, Paris, F-75252, France
- Graphene Labs, Fondazione Istituto Italiano di Tecnologia, Via Morego, Genova, I-16163, Italy
| | - Francesco Mauri
- Sorbonne Université, CNRS, Institut des Nanosciences de Paris, UMR7588, Paris, F-75252, France
- Graphene Labs, Fondazione Istituto Italiano di Tecnologia, Via Morego, Genova, I-16163, Italy
| | - Lorenzo Monacelli
- Graphene Labs, Fondazione Istituto Italiano di Tecnologia, Via Morego, Genova, I-16163, Italy
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 5, Roma, I-00185, Italy
| | - Ryosuke Akashi
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8654, Japan
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121025, Russia
- Dipartimento di Fisica, Università di Roma Sapienza, Piazzale Aldo Moro 5, Roma, I-00185, Italy
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8654, Japan
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15
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Semenok DV, Zhou D, Kvashnin AG, Huang X, Galasso M, Kruglov IA, Ivanova AG, Gavriliuk AG, Chen W, Tkachenko NV, Boldyrev AI, Troyan I, Oganov AR, Cui T. Novel Strongly Correlated Europium Superhydrides. J Phys Chem Lett 2021; 12:32-40. [PMID: 33296213 DOI: 10.1021/acs.jpclett.0c03331] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We conducted a joint experimental-theoretical investigation of the high-pressure chemistry of europium polyhydrides at pressures of 86-130 GPa. We discovered several novel magnetic Eu superhydrides stabilized by anharmonic effects: cubic EuH9, hexagonal EuH9, and an unexpected cubic (Pm3n) clathrate phase, Eu8H46. Monte Carlo simulations indicate that cubic EuH9 has antiferromagnetic ordering with TN of up to 24 K, whereas hexagonal EuH9 and Pm3n-Eu8H46 possess ferromagnetic ordering with TC = 137 and 336 K, respectively. The electron-phonon interaction is weak in all studied europium hydrides, and their magnetic ordering excludes s-wave superconductivity, except, perhaps, for distorted pseudohexagonal EuH9. The equations of state predicted within the DFT+U approach (U - J were found within linear response theory) are in close agreement with the experimental data. This work shows the great influence of the atomic radius on symmetry-breaking distortions of the crystal structures of superhydrides and on their thermodynamic stability.
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Affiliation(s)
- Dmitrii V Semenok
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Bolshoy Boulevard 30, bld. 1, Moscow 143026, Russia
| | - Di Zhou
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Bolshoy Boulevard 30, bld. 1, Moscow 143026, Russia
| | - Xiaoli Huang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Michele Galasso
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Bolshoy Boulevard 30, bld. 1, Moscow 143026, Russia
| | - Ivan A Kruglov
- Moscow Institute of Physics and Technology, 9 Institutsky Lane, Dolgoprudny 141700, Russia
- Dukhov Research Institute of Automatics (VNIIA), Moscow 127055, Russia
| | - Anna G Ivanova
- Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii pr-t, Moscow 119333, Russia
| | - Alexander G Gavriliuk
- Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii pr-t, Moscow 119333, Russia
- IC RAS Institute for Nuclear Research, Russian Academy of Sciences, Moscow 117312, Russia
| | - Wuhao Chen
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Nikolay V Tkachenko
- Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, Utah 84322-0300, United States
| | - Alexander I Boldyrev
- Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, Utah 84322-0300, United States
| | - Ivan Troyan
- Shubnikov Institute of Crystallography, Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii pr-t, Moscow 119333, Russia
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Bolshoy Boulevard 30, bld. 1, Moscow 143026, Russia
| | - Tian Cui
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, China
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16
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Chen W, Semenok DV, Kvashnin AG, Huang X, Kruglov IA, Galasso M, Song H, Duan D, Goncharov AF, Prakapenka VB, Oganov AR, Cui T. Synthesis of molecular metallic barium superhydride: pseudocubic BaH 12. Nat Commun 2021; 12:273. [PMID: 33431840 PMCID: PMC7801595 DOI: 10.1038/s41467-020-20103-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 11/13/2020] [Indexed: 01/29/2023] Open
Abstract
Following the discovery of high-temperature superconductivity in the La-H system, we studied the formation of new chemical compounds in the barium-hydrogen system at pressures from 75 to 173 GPa. Using in situ generation of hydrogen from NH3BH3, we synthesized previously unknown superhydride BaH12 with a pseudocubic (fcc) Ba sublattice in four independent experiments. Density functional theory calculations indicate close agreement between the theoretical and experimental equations of state. In addition, we identified previously known P6/mmm-BaH2 and possibly BaH10 and BaH6 as impurities in the samples. Ab initio calculations show that newly discovered semimetallic BaH12 contains H2 and H3- molecular units and detached H12 chains which are formed as a result of a Peierls-type distortion of the cubic cage structure. Barium dodecahydride is a unique molecular hydride with metallic conductivity that demonstrates the superconducting transition around 20 K at 140 GPa.
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Affiliation(s)
- Wuhao Chen
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
| | - Dmitrii V Semenok
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 143026, Russia
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 143026, Russia
| | - Xiaoli Huang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.
| | - Ivan A Kruglov
- Moscow Institute of Physics and Technology, 9 Institutsky Lane, Dolgoprudny, 141700, Russia
- Dukhov Research Institute of Automatics (VNIIA), Moscow, 127055, Russia
| | - Michele Galasso
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 143026, Russia
| | - Hao Song
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
| | - Defang Duan
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
| | - Alexander F Goncharov
- Earth and Planets Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, DC, 20015, USA
| | - Vitali B Prakapenka
- Center for Advanced Radiation Sources, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL, 60637, USA
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 143026, Russia.
| | - Tian Cui
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.
- School of Physical Science and Technology, Ningbo University, Ningbo, 315211, China.
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17
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Chernozatonskii LA, Artyukh AA, Kvashnin AG, Kvashnin DG. Mechanical Engineering Effect in Electronic and Optical Properties of Graphene Nanomeshes. ACS Appl Mater Interfaces 2020; 12:55189-55194. [PMID: 33225682 DOI: 10.1021/acsami.0c17060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Here, we present an ab initio study of ways for engineering electronic and optical properties of bilayered graphene nanomeshes with various stacking types via mechanical deformations. Strong evolution of the electronic structure and absorption spectra during deformation is studied and analyzed. The obtained results are of significant importance and open up new prospects for using such nanomeshes as materials with easily controlled properties in electronic and optoelectronic nanodevices.
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Affiliation(s)
- Leonid A Chernozatonskii
- Emanuel Institute of Biochemical Physics RAS, 4 Kosigin Street, Moscow 119334, Russian Federation
- School of Chemistry and Technology of Polymeric Materials, Plekhanov Russian University of Economics, Moscow 117997 Russian Federation
| | - Anastasiya A Artyukh
- Emanuel Institute of Biochemical Physics RAS, 4 Kosigin Street, Moscow 119334, Russian Federation
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center 121025, 30 Bolshoy Boulevard, bld. 1, Moscow 143026, Russian Federation
| | - Dmitry G Kvashnin
- Emanuel Institute of Biochemical Physics RAS, 4 Kosigin Street, Moscow 119334, Russian Federation
- National University of Science and Technology MISiS, 4 Leninskiy Prospekt, Moscow 119049, Russian Federation
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18
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Firestein KL, von Treifeldt JE, Kvashnin DG, Fernando JFS, Zhang C, Kvashnin AG, Podryabinkin EV, Shapeev AV, Siriwardena DP, Sorokin PB, Golberg D. Young's Modulus and Tensile Strength of Ti 3C 2 MXene Nanosheets As Revealed by In Situ TEM Probing, AFM Nanomechanical Mapping, and Theoretical Calculations. Nano Lett 2020; 20:5900-5908. [PMID: 32633975 DOI: 10.1021/acs.nanolett.0c01861] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Two-dimensional transition metal carbides, that is, MXenes and especially Ti3C2, attract attention due to their excellent combination of properties. Ti3C2 nanosheets could be the material of choice for future flexible electronics, energy storage, and electromechanical nanodevices. There has been limited information available on the mechanical properties of Ti3C2, which is essential for their utilization. We have fabricated Ti3C2 nanosheets and studied their mechanical properties using direct in situ tensile tests inside a transmission electron microscope, quantitative nanomechanical mapping, and theoretical calculations employing machine-learning derived potentials. Young's modulus in the direction perpendicular to the Ti3C2 basal plane was found to be 80-100 GPa. The tensile strength of Ti3C2 nanosheets reached up to 670 MPa for ∼40 nm thin nanoflakes, while a strong dependence of tensile strength on nanosheet thickness was demonstrated. Theoretical calculations allowed us to study mechanical characteristics of Ti3C2 as a function of nanosheet geometrical parameters and structural defect concentration.
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Affiliation(s)
- Konstantin L Firestein
- Centre for Materials Science and School of Chemistry and Physics, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Joel E von Treifeldt
- Centre for Materials Science and School of Chemistry and Physics, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Dmitry G Kvashnin
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygina 4 Street, Moscow 119334, Russian Federation
- National University of Science and Technology "MISiS", Leninskiy prospekt 4, Moscow 119049, Russian Federation
| | - Joseph F S Fernando
- Centre for Materials Science and School of Chemistry and Physics, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Chao Zhang
- Centre for Materials Science and School of Chemistry and Physics, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, 30, Building. 1 Bolshoy Boulevard, Moscow 121205, Russian Federation
| | - Evgeny V Podryabinkin
- Skolkovo Institute of Science and Technology, 30, Building. 1 Bolshoy Boulevard, Moscow 121205, Russian Federation
| | - Alexander V Shapeev
- Skolkovo Institute of Science and Technology, 30, Building. 1 Bolshoy Boulevard, Moscow 121205, Russian Federation
| | - Dumindu P Siriwardena
- Centre for Materials Science and School of Chemistry and Physics, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Pavel B Sorokin
- National University of Science and Technology "MISiS", Leninskiy prospekt 4, Moscow 119049, Russian Federation
- Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny, Moscow Region 141701, Russian Federation
| | - Dmitri Golberg
- Centre for Materials Science and School of Chemistry and Physics, Science and Engineering Faculty, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 3050044, Japan
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Kvashnin AG, Rybkovskiy DV, Filonenko VP, Bugakov VI, Zibrov IP, Brazhkin VV, Oganov AR, Osiptsov AA, Zakirov AY. WB 5- x : Synthesis, Properties, and Crystal Structure-New Insights into the Long-Debated Compound. Adv Sci (Weinh) 2020; 7:2000775. [PMID: 32832351 PMCID: PMC7435258 DOI: 10.1002/advs.202000775] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/29/2020] [Indexed: 05/30/2023]
Abstract
The recent theoretical prediction of a new compound, WB5, has spurred the interest in tungsten borides and their possible implementation in industry. In this research, the experimental synthesis and structural description of a boron-rich tungsten boride and measurements of its mechanical properties are performed. The ab initio calculations of the structural energies corresponding to different local structures make it possible to formulate the rules determining the likely local motifs in the disordered versions of the WB5 structure, all of which involve boron deficit. The generated disordered WB4.18 and WB4.86 models both perfectly match the experimental data, but the former is the most energetically preferable. The precise crystal structure, elastic constants, hardness, and fracture toughness of this phase are calculated, and these results agree with the experimental findings. Because of the compositional and structural similarity with predicted WB5, this phase is denoted as WB5- x . Previously incorrectly referred to as "WB4," it is distinct from earlier theoretically suggested WB4, a phase with a different crystal structure that has not yet been synthesized and is predicted to be thermodynamically stable at pressures above 1 GPa. Mild synthesis conditions (enabling a scalable synthesis) and excellent mechanical properties make WB5- x a very promising material for drilling technology.
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Affiliation(s)
- Alexander G. Kvashnin
- Skolkovo Institute of Science and TechnologySkolkovo Innovation Center3 Nobel StreetMoscow121025Russia
| | - Dmitry V. Rybkovskiy
- Skolkovo Institute of Science and TechnologySkolkovo Innovation Center3 Nobel StreetMoscow121025Russia
- A. M. Prokhorov General Physics Institute of RAS38 Vavilov StreetMoscow119991Russia
| | - Vladimir P. Filonenko
- Vereshchagin Institute for High Pressure Physics of the Russian Academy of SciencesTroitsk108840Russia
| | - Vasilii I. Bugakov
- Vereshchagin Institute for High Pressure Physics of the Russian Academy of SciencesTroitsk108840Russia
| | - Igor P. Zibrov
- Vereshchagin Institute for High Pressure Physics of the Russian Academy of SciencesTroitsk108840Russia
| | - Vadim V. Brazhkin
- Vereshchagin Institute for High Pressure Physics of the Russian Academy of SciencesTroitsk108840Russia
| | - Artem R. Oganov
- Skolkovo Institute of Science and TechnologySkolkovo Innovation Center3 Nobel StreetMoscow121025Russia
- Moscow Institute of Physics and Technology9 Institutsky LaneDolgoprudny141700Russia
- International Center for Materials DiscoveryNorthwestern Polytechnical UniversityXi'an710072China
| | - Andrey A. Osiptsov
- Skolkovo Institute of Science and TechnologySkolkovo Innovation Center3 Nobel StreetMoscow121025Russia
| | - Artem Ya Zakirov
- Gazpromneft Science & Technology Center75‐79 Moika River Embankment, Bldg. DSt. Petersburg190000Russia
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20
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Tikhomirova KA, Tantardini C, Sukhanova EV, Popov ZI, Evlashin SA, Tarkhov MA, Zhdanov VL, Dudin AA, Oganov AR, Kvashnin DG, Kvashnin AG. Exotic Two-Dimensional Structure: The First Case of Hexagonal NaCl. J Phys Chem Lett 2020; 11:3821-3827. [PMID: 32330050 DOI: 10.1021/acs.jpclett.0c00874] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
NaCl is one of the simplest compounds and was thought to be well-understood, and yet, unexpected complexities related to it were uncovered at high pressure and in low-dimensional states. Here, exotic hexagonal NaCl thin films on the (110) diamond surface were crystallized in the experiment following a theoretical prediction based on ab initio evolutionary algorithm USPEX. State-of-the-art calculations and experiments showed the existence of a hexagonal NaCl thin film, which is due to the strong chemical interaction of the NaCl film with the diamond substrate.
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Affiliation(s)
- Kseniya A Tikhomirova
- Skolkovo Institute of Science and Technology, 30, bld. 1 Bolshoy Boulevard, Moscow 121205, Russia
| | - Christian Tantardini
- Skolkovo Institute of Science and Technology, 30, bld. 1 Bolshoy Boulevard, Moscow 121205, Russia
| | - Ekaterina V Sukhanova
- Emanuel Institute of Biochemical Physics RAS, 4 Kosigina Street, Moscow 119334, Russia
- Moscow Institute of Physics and Technology, 9 Institutsky Pereulok, Dolgoprudny 141700, Russia
| | - Zakhar I Popov
- Emanuel Institute of Biochemical Physics RAS, 4 Kosigina Street, Moscow 119334, Russia
| | - Stanislav A Evlashin
- Skolkovo Institute of Science and Technology, 30, bld. 1 Bolshoy Boulevard, Moscow 121205, Russia
| | - Mikhail A Tarkhov
- Institute of Nanotechnologies of Microelectronics of the Russian Academy of Sciences, 32 A Leninsky Prospekt, Moscow 119991, Russia
| | | | - Alexander A Dudin
- Institute of Nanotechnologies of Microelectronics of the Russian Academy of Sciences, 32 A Leninsky Prospekt, Moscow 119991, Russia
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, 30, bld. 1 Bolshoy Boulevard, Moscow 121205, Russia
- Moscow Institute of Physics and Technology, 9 Institutsky Pereulok, Dolgoprudny 141700, Russia
- International Center for Materials Discovery, Northwestern Polytechnical University, Xi'an 710072, China
| | - Dmitry G Kvashnin
- Emanuel Institute of Biochemical Physics RAS, 4 Kosigina Street, Moscow 119334, Russia
- Moscow Institute of Physics and Technology, 9 Institutsky Pereulok, Dolgoprudny 141700, Russia
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, 30, bld. 1 Bolshoy Boulevard, Moscow 121205, Russia
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21
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Rybkovskiy DV, Kvashnin AG, Kvashnina YA, Oganov AR. Structure, Stability, and Mechanical Properties of Boron-Rich Mo-B Phases: A Computational Study. J Phys Chem Lett 2020; 11:2393-2401. [PMID: 32125852 DOI: 10.1021/acs.jpclett.0c00242] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Molybdenum borides were studied theoretically using first-principles calculations, parameterized lattice model, and global optimization techniques to determine stable crystal structures. Our calculations reveal the structures of known Mo-B phases, attaining close agreement with experiment. Following our developed lattice model, we describe in detail the crystal structure of boron-rich MoBx phases with 3 ≤ x ≤ 9 as the hexagonal P63/mmc-MoB3 structure with Mo atoms partially replaced by triangular boron units. The most energetically stable arrangement of these B3 units corresponds to their uniform distribution in the bulk, which leads to the formation of a disordered nonstoichiometric phase, with ordering arising at compositions close to x = 5 because of a strong repulsive interaction between neighboring B3 units. The most energetically favorable structures of MoBx correspond to the compositions 4 ≲ x ≤ 5, with MoB5 being the boron-richest stable phase. The estimated hardness of MoB5 is 37-39 GPa, suggesting that the boron-rich phases are potentially superhard.
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Affiliation(s)
- Dmitry V Rybkovskiy
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow 121205, Russia
- A. M. Prokhorov General Physics Institute of RAS, 38 Vavilov Street, Moscow 119991, Russia
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow 121205, Russia
- Moscow Institute of Physics and Technology, 9 Institutsky Lane, Dolgoprudny 141700, Russia
| | - Yulia A Kvashnina
- Pirogov Russian National Research Medical University, 1 Ostrovityanova Street, Moscow 117997, Russia
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow 121205, Russia
- Moscow Institute of Physics and Technology, 9 Institutsky Lane, Dolgoprudny 141700, Russia
- International Center for Materials Discovery, Northwestern Polytechnical University, Xi'an 710072, China
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22
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Zhou D, Semenok DV, Xie H, Huang X, Duan D, Aperis A, Oppeneer PM, Galasso M, Kartsev AI, Kvashnin AG, Oganov AR, Cui T. High-Pressure Synthesis of Magnetic Neodymium Polyhydrides. J Am Chem Soc 2020; 142:2803-2811. [DOI: 10.1021/jacs.9b10439] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Di Zhou
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Dmitrii V. Semenok
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow 121205, Russia
| | - Hui Xie
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Xiaoli Huang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Defang Duan
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Alex Aperis
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, Uppsala SE-75120, Sweden
| | - Peter M. Oppeneer
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, Uppsala SE-75120, Sweden
| | - Michele Galasso
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow 121205, Russia
| | - Alexey I. Kartsev
- Computing Center of Far Eastern Branch of the Russian Academy of Sciences (CC FEB RAS), Khabarovsk 680000, Russian Federation
- School of Mathematics and Physics, Queen’s University Belfast, Belfast, Northern Ireland BT7 1NN, United Kingdom
| | - Alexander G. Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow 121205, Russia
| | - Artem R. Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow 121205, Russia
- International Center for Materials Discovery, Northwestern Polytechnical University, Xi’an 710072, China
| | - Tian Cui
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, China
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23
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Joseph T, Ghorbani-Asl M, Kvashnin AG, Larionov KV, Popov ZI, Sorokin PB, Krasheninnikov AV. Nonstoichiometric Phases of Two-Dimensional Transition-Metal Dichalcogenides: From Chalcogen Vacancies to Pure Metal Membranes. J Phys Chem Lett 2019; 10:6492-6498. [PMID: 31589053 DOI: 10.1021/acs.jpclett.9b02529] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Two-dimensional (2D) membranes consisting of a single layer of Mo atoms were recently manufactured [ Adv. Mater. 2018 , 30 , 1707281 ] from MoSe2 sheets by sputtering Se atoms using an electron beam in a transmission electron microscope. This is an unexpected result as formation of Mo clusters should energetically be more favorable. To get microscopic insights into the energetics of realistic Mo membranes and nonstoichiometric phases of transition-metal dichalcogenides (TMDs) MaXb, where M = Mo and W and X = S, Se, and Te, we carry out first-principles calculations and demonstrate that the membranes, which can be referred to as metallic quantum dots embedded into a semiconducting matrix, can be stabilized by charge transfer. We also show that an ideal neutral 2D Mo or W sheet is not flat but a corrugated structure, with a square lattice being the lowest-energy configuration. We further demonstrate that several intermediate nonstoichiometric phases of TMDs are possible as they have lower formation energies than pure metal membranes. Among them, the orthorhombic metallic 2D M4X4 phase is particularly stable. Finally, we study the properties of this phase in detail and discuss how it can be manufactured by the top-down approaches.
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Affiliation(s)
- T Joseph
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , 01328 Dresden , Germany
| | - M Ghorbani-Asl
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , 01328 Dresden , Germany
| | - A G Kvashnin
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center , 3 Nobel Street , Moscow 121205 , Russia
| | - K V Larionov
- National University of Science and Technology "MISIS" , Leninsky prospect 4 , Moscow 119049 , Russia
- Moscow Institute of Physics and Technology , Institutsky lane 9 , Dolgoprudny , Moscow region , 141700 , Russian Federation
| | - Z I Popov
- National University of Science and Technology "MISIS" , Leninsky prospect 4 , Moscow 119049 , Russia
- Emanuel Institute of Biochemical Physics RAS , Moscow 119334 , Russia
| | - P B Sorokin
- National University of Science and Technology "MISIS" , Leninsky prospect 4 , Moscow 119049 , Russia
- Moscow Institute of Physics and Technology , Institutsky lane 9 , Dolgoprudny , Moscow region , 141700 , Russian Federation
- Emanuel Institute of Biochemical Physics RAS , Moscow 119334 , Russia
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , 01328 Dresden , Germany
- Department of Applied Physics , Aalto University , P.O. Box 11100, 00076 Aalto , Finland
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Kvashnin AG, Kvashnin DG, Oganov AR. Novel Unexpected Reconstructions of (100) and (111) Surfaces of NaCl: Theoretical Prediction. Sci Rep 2019; 9:14267. [PMID: 31582761 PMCID: PMC6776646 DOI: 10.1038/s41598-019-50548-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 09/12/2019] [Indexed: 11/09/2022] Open
Abstract
We have predicted stable reconstructions of the (100) and (111) surfaces of NaCl using the global optimization algorithm USPEX. Several new reconstructions, together with the previously reported ones, are found. For the cleaved bare (100) surface, pure Na and pure Cl are the only stable surface phases. Our study of the (111) surface shows that a newly predicted Na3Cl-(1 × 1) reconstruction is thermodynamically stable in a wide range of chlorine chemical potentials. It has a sawtooth-like profile where each facet reproduces the (100) surface of rock-salt NaCl, hinting on the preferred growth of the (100) surface. We used Bader charge analysis to explain the preferable formation of this sawtooth-like Na3Cl-(1 × 1) reconstruction of the (111) surface of NaCl. We find that at a very high chemical potential of Na, the polar (and normally absent) (111) surface becomes part of the equilibrium crystal morphology. At both very high and very low chemical potentials of Cl, we predict a large decrease of surface energy and fracture toughness (the Rehbinder effect).
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Affiliation(s)
- Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121205, Russia.,Moscow Institute of Physics and Technology, 9 Institutsky Pereulok, Dolgoprudny, 141700, Russia
| | - Dmitry G Kvashnin
- Emanuel Institute of Biochemical Physics RAS, 4 Kosigina Street, Moscow, 119334, Russia. .,National University of Science and Technology MISIS, 4 Leninskiy Prospekt, Moscow, 119049, Russia.
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 3 Nobel Street, Moscow, 121205, Russia.,Moscow Institute of Physics and Technology, 9 Institutsky Pereulok, Dolgoprudny, 141700, Russia.,International Center for Materials Discovery, Northwestern Polytechnical University, Xi'an, 710072, China
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25
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Abstract
We have studied the formation and stability of high-pressure iron mono-nitride phases, and in particular a new magnetic phase with a NiAs-type structure.
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Affiliation(s)
- Alexey Kartsev
- Computing Center FEB RAS
- Khabarovsk
- Russia
- National Research Tomsk State University
- 36, Lenina pr
| | - Oleg D. Feya
- Moscow Institute of Physics and Technology
- Dolgoprudny
- Moscow Region 141700
- Russia
| | - Nina Bondarenko
- Condensed Matter Theory Group
- Physics Department
- Uppsala University
- S-751 21 Uppsala
- Sweden
| | - Alexander G. Kvashnin
- Moscow Institute of Physics and Technology
- Dolgoprudny
- Moscow Region 141700
- Russia
- Skolkovo Institute of Science and Technology
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26
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Kvashnin AG, Semenok DV, Kruglov IA, Wrona IA, Oganov AR. High-Temperature Superconductivity in a Th-H System under Pressure Conditions. ACS Appl Mater Interfaces 2018; 10:43809-43816. [PMID: 30512924 DOI: 10.1021/acsami.8b17100] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
New stable phase thorium decahydride Fm3̅ m-ThH10, a high-temperature superconductor with TC up to 241 K (-32 °C), critical field HC up to 71 T, and superconducting gap Δ0 of 52 meV at 80-100 GPa, is predicted by evolutionary algorithm USPEX. Another phase, P21/ c-ThH7, is found to be a superconductor with TC of 62 K. Analysis of the superconducting state was performed within Eliashberg formalism, and HC( T), Δ( T), and TC( P) functions with a jump in the specific heat at critical temperature were calculated. Several other new thorium hydrides were predicted to be stable under pressure, including ThH3, Th3H10, ThH4, and ThH6. Thorium (which has s2 d2 electronic configuration) forms high- TC polyhydrides similar to those formed by s2 d1 metals (Y-La-Ac). Thorium belongs to the Mg-Ca-Sc-Y-La-Ac family of elements forming high- TC superconducting hydrides.
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Affiliation(s)
- Alexander G Kvashnin
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center , 3 Nobel Street , Moscow 143026 , Russia
- Moscow Institute of Physics and Technology , 9 Institutskiy Lane , Dolgoprudny 141700 , Russia
| | - Dmitrii V Semenok
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center , 3 Nobel Street , Moscow 143026 , Russia
- Moscow Institute of Physics and Technology , 9 Institutskiy Lane , Dolgoprudny 141700 , Russia
| | - Ivan A Kruglov
- Moscow Institute of Physics and Technology , 9 Institutskiy Lane , Dolgoprudny 141700 , Russia
- Dukhov Research Institute of Automatics (VNIIA) , Moscow 127055 , Russia
| | - Izabela A Wrona
- Institute of Physics , Jan Dlugosz University in Czestochowa , Armii Krajowej 13/15 Avenue , 42-200 Czestochowa , Poland
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center , 3 Nobel Street , Moscow 143026 , Russia
- Dukhov Research Institute of Automatics (VNIIA) , Moscow 127055 , Russia
- International Center for Materials Discovery , Northwestern Polytechnical University , Xi'an 710072 , China
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Kruglov IA, Kvashnin AG, Goncharov AF, Oganov AR, Lobanov SS, Holtgrewe N, Jiang S, Prakapenka VB, Greenberg E, Yanilkin AV. Uranium polyhydrides at moderate pressures: Prediction, synthesis, and expected superconductivity. Sci Adv 2018; 4:eaat9776. [PMID: 30333994 PMCID: PMC6184697 DOI: 10.1126/sciadv.aat9776] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 09/04/2018] [Indexed: 05/31/2023]
Abstract
Hydrogen-rich hydrides attract great attention due to recent theoretical (1) and then experimental discovery of record high-temperature superconductivity in H3S [T c = 203 K at 155 GPa (2)]. Here we search for stable uranium hydrides at pressures up to 500 GPa using ab initio evolutionary crystal structure prediction. Chemistry of the U-H system turned out to be extremely rich, with 14 new compounds, including hydrogen-rich UH5, UH6, U2H13, UH7, UH8, U2H17, and UH9. Their crystal structures are based on either common face-centered cubic or hexagonal close-packed uranium sublattice and unusual H8 cubic clusters. Our high-pressure experiments at 1 to 103 GPa confirm the predicted UH7, UH8, and three different phases of UH5, raising confidence about predictions of the other phases. Many of the newly predicted phases are expected to be high-temperature superconductors. The highest-T c superconductor is UH7, predicted to be thermodynamically stable at pressures above 22 GPa (with T c = 44 to 54 K), and this phase remains dynamically stable upon decompression to zero pressure (where it has T c = 57 to 66 K).
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Affiliation(s)
- Ivan A. Kruglov
- Dukhov Research Institute of Automatics (VNIIA), Moscow 127055, Russian Federation
- Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russian Federation
| | - Alexander G. Kvashnin
- Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russian Federation
- Skolkovo Institute of Science and Technology, 3 Nobel St., Moscow 143026, Russian Federation
| | - Alexander F. Goncharov
- Key Laboratory of Materials Physics, Institute of Solid State Physics CAS, Hefei 230031, China
- Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015, USA
| | - Artem R. Oganov
- Dukhov Research Institute of Automatics (VNIIA), Moscow 127055, Russian Federation
- Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russian Federation
- Skolkovo Institute of Science and Technology, 3 Nobel St., Moscow 143026, Russian Federation
| | - Sergey S. Lobanov
- Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015, USA
- GFZ German Research Center for Geosciences, Section 4.3, Telegrafenberg, 14473 Potsdam, Germany
| | - Nicholas Holtgrewe
- Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015, USA
- Center for Advanced Radiations Sources, University of Chicago, Chicago, IL 60637, USA
| | - Shuqing Jiang
- Key Laboratory of Materials Physics, Institute of Solid State Physics CAS, Hefei 230031, China
| | - Vitali B. Prakapenka
- Center for Advanced Radiations Sources, University of Chicago, Chicago, IL 60637, USA
| | - Eran Greenberg
- Center for Advanced Radiations Sources, University of Chicago, Chicago, IL 60637, USA
| | - Alexey V. Yanilkin
- Dukhov Research Institute of Automatics (VNIIA), Moscow 127055, Russian Federation
- Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russian Federation
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28
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Kvashnin AG, Zakaryan HA, Zhao C, Duan Y, Kvashnina YA, Xie C, Dong H, Oganov AR. New Tungsten Borides, Their Stability and Outstanding Mechanical Properties. J Phys Chem Lett 2018; 9:3470-3477. [PMID: 29860838 DOI: 10.1021/acs.jpclett.8b01262] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We predict new tungsten borides, some of which are promising hard materials that are expected to be stable in a wide range of conditions, according to the computed composition-temperature phase diagram. New boron-rich compound WB5 is predicted to be superhard, with a Vickers hardness of 45 GPa, to possess high fracture toughness of ∼4 MPa·m0.5, and to be thermodynamically stable in a wide range of temperatures at ambient pressure. Temperature dependences of the mechanical properties of the boron-richest WB3 and WB5 phases were studied using quasiharmonic and anharmonic approximations. Our results suggest that WB5 remains a high-performance material even at very high temperatures.
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Affiliation(s)
- Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center , 3 Nobel Street , 143026 Moscow , Russia
- Moscow Institute of Physics and Technology , 9 Institutsky Lane , 141700 Dolgoprudny , Russia
| | - Hayk A Zakaryan
- Yerevan State University , 1 Alex Manoogian Street , 0025 Yerevan , Armenia
| | - Changming Zhao
- School of Physics , China University of Mining and Technology , Xuzhou , Jiangsu 221116 , China
| | - Yifeng Duan
- School of Physics , China University of Mining and Technology , Xuzhou , Jiangsu 221116 , China
| | - Yulia A Kvashnina
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center , 3 Nobel Street , 143026 Moscow , Russia
- Moscow Institute of Physics and Technology , 9 Institutsky Lane , 141700 Dolgoprudny , Russia
| | - Congwei Xie
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center , 3 Nobel Street , 143026 Moscow , Russia
- International Center for Materials Discovery , Northwestern Polytechnical University , Xi'an 710072 , China
| | - Huafeng Dong
- School of Physics and Optoelectronic Engineering , Guangdong University of Technology , Guangzhou 510006 , China
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center , 3 Nobel Street , 143026 Moscow , Russia
- Moscow Institute of Physics and Technology , 9 Institutsky Lane , 141700 Dolgoprudny , Russia
- International Center for Materials Discovery , Northwestern Polytechnical University , Xi'an 710072 , China
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Semenok DV, Kvashnin AG, Kruglov IA, Oganov AR. Actinium Hydrides AcH 10, AcH 12, and AcH 16 as High-Temperature Conventional Superconductors. J Phys Chem Lett 2018; 9:1920-1926. [PMID: 29589444 DOI: 10.1021/acs.jpclett.8b00615] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The stability of numerous unexpected actinium hydrides was predicted via the evolutionary algorithm USPEX. The electron-phonon interaction was investigated for the hydrogen-richest and most symmetric phases: R3̅ m-AcH10, I4/ mmm-AcH12, and P6̅ m2-AcH16. Predicted structures of actinium hydrides are consistent with all previously studied Ac-H phases and demonstrate phonon-mediated high-temperature superconductivity with TC in the range of 204-251 K for R3̅ m-AcH10 at 200 GPa and 199-241 K for P6̅ m2-AcH16 at 150 GPa, which was estimated by directly solving the Eliashberg equation. Actinium belongs to the series of d1 elements (Sc-Y-La-Ac) that form high- TC superconducting (HTSC) hydrides. Combining this observation with previous predictions of p0-HTSC hydrides (MgH6 and CaH6), we propose that p0 and d1 metals with low-lying empty orbitals tend to form phonon-mediated HTSC metal polyhydrides.
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Affiliation(s)
- Dmitrii V Semenok
- Skolkovo Innovation Center , Skolkovo Institute of Science and Technology , 3 Nobel Street , Moscow 143026 , Russian Federation
- Moscow Institute of Physics and Technology , 9 Institutsky Lane , Dolgoprudny 141700 , Russian Federation
| | - Alexander G Kvashnin
- Skolkovo Innovation Center , Skolkovo Institute of Science and Technology , 3 Nobel Street , Moscow 143026 , Russian Federation
- Moscow Institute of Physics and Technology , 9 Institutsky Lane , Dolgoprudny 141700 , Russian Federation
| | - Ivan A Kruglov
- Moscow Institute of Physics and Technology , 9 Institutsky Lane , Dolgoprudny 141700 , Russian Federation
- Dukhov Research Institute of Automatics (VNIIA) , Moscow 127055 , Russian Federation
| | - Artem R Oganov
- Skolkovo Innovation Center , Skolkovo Institute of Science and Technology , 3 Nobel Street , Moscow 143026 , Russian Federation
- Moscow Institute of Physics and Technology , 9 Institutsky Lane , Dolgoprudny 141700 , Russian Federation
- Dukhov Research Institute of Automatics (VNIIA) , Moscow 127055 , Russian Federation
- International Center for Materials Discovery , Northwestern Polytechnical University , Xi'an 710072 , China
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Zakaryan HA, Kvashnin AG, Oganov AR. Stable reconstruction of the (110) surface and its role in pseudocapacitance of rutile-like RuO 2. Sci Rep 2017; 7:10357. [PMID: 28871095 PMCID: PMC5583189 DOI: 10.1038/s41598-017-10331-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 08/08/2017] [Indexed: 11/09/2022] Open
Abstract
Surfaces of rutile-like RuO2, especially the most stable (110) surface, are important for catalysis, sensing and charge storage applications. Structure, chemical composition, and properties of the surface depend on external conditions. Using the evolutionary prediction method USPEX, we found stable reconstructions of the (110) surface. Two stable reconstructions, RuO4-(2 × 1) and RuO2-(1 × 1), were found, and the surface phase diagram was determined. The new RuO4-(2 × 1) reconstruction is stable in a wide range of environmental conditions, its simulated STM image perfectly matches experimental data, it is more thermodynamically stable than previously proposed reconstructions, and explains well pseudocapacitance of RuO2 cathodes.
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Affiliation(s)
- Hayk A Zakaryan
- Yerevan State University, 1 Alex Manoogian St., 0025, Yerevan, Armenia
| | - Alexander G Kvashnin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 143026, 3 Nobel Street, Moscow, Russian Federation. .,Moscow Institute of Physics and Technology, 141700, 9 Institutsky lane, Dolgoprudny, Russian Federation.
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, 143026, 3 Nobel Street, Moscow, Russian Federation.,Moscow Institute of Physics and Technology, 141700, 9 Institutsky lane, Dolgoprudny, Russian Federation.,Department of Geosciences and Center for Materials by Design, Institute for Advanced Computational Science, State University of New York, Stony Brook, NY, 11794-2100, USA.,International Center for Materials Discovery, Northwestern Polytechnical University, Xi'an, 710072, China
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Abstract
Here we present an investigation of new quasi-two-dimensional heterostructures based on the alternation of bounded carbon and boron nitride layers (C/BN). We carried out a theoretical study of the atomic structure, stability and electronic properties of the proposed heterostructures. Such ultrathin quasi-two-dimensional C/BN films can be synthesized by means of chemically induced phase transition by connection of the layers of multilayered h-BN/graphene van der Waals heterostructures, which is indicated by the negative phase transition pressure in the calculated phase diagrams (P, T) of the films. It was shown that the band gap value of the C/BN films spans the infrared and visible spectrum. We hope that the proposed films and fabrication method can be considered as a possible route to obtain nanostructures with a controllable band gap in wide energy range. This makes these materials potentially suitable for a variety of applications, including photovoltaics, photoelectronics and more.
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Affiliation(s)
- Dmitry G Kvashnin
- Emanuel Institute of Biochemical Physics, Russian Academy of Science, 4 Kosigin Street, Moscow, 119334, Russian Federation. National University of Science and Technology MISiS, 4 Leninskiy Prospekt, Moscow, 119049, Russian Federation
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Abstract
Nitrides, carbides, and borides of transition metals are an attractive class of hard materials. Our recent preliminary explorations of the binary chemical compounds indicated that chromium-based materials are among the hardest transition metal compounds. Motivated by this, here we explore in detail the binary Cr-B, Cr-C, and Cr-N systems using global optimization techniques. Calculated enthalpy of formation and hardness of predicted materials were used for Pareto optimization to define the hardest materials with the lowest energy. Our calculations recover all numerous known stable compounds (except Cr23C6 with its large unit cell) and discover a novel stable phase Pmn21-Cr2C. We resolve the structure of Cr2N and find it to be of anti-CaCl2 type (space group Pnnm). Many of these phases possess remarkable hardness, but only CrB4 is superhard (Vickers hardness 48 GPa). Among chromium compounds, borides generally possess the highest hardnesses and greatest stability. Under pressure, we predict stabilization of a layered TMDC-like phase of Cr2N, a WC-type phase of CrN, and a new compound CrN4. Nitrogen-rich chromium nitride CrN4 is a high-energy-density material featuring polymeric nitrogen chains. In the presence of metal atoms (e.g., Cr), polymerization of nitrogen takes place at much lower pressures; CrN4 becomes stable at ∼15 GPa (cf. 110 GPa for synthesis of pure polymeric nitrogen).
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Affiliation(s)
- Alexander G Kvashnin
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center, 3 Nobel Street, Moscow 143026, Russian Federation
- Moscow Institute of Physics and Technology , 9 Institutsky Lane, Dolgoprudny 141700, Russian Federation
| | - Artem R Oganov
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center, 3 Nobel Street, Moscow 143026, Russian Federation
- Moscow Institute of Physics and Technology , 9 Institutsky Lane, Dolgoprudny 141700, Russian Federation
- Department of Geosciences and Center for Materials by Design, Institute for Advanced Computational Science, State University of New York , Stony Brook, New York 11794-2100, United States
- International Center for Materials Design, Northwestern Polytechnical University , Xi'an 710072, China
| | - Artem I Samtsevich
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center, 3 Nobel Street, Moscow 143026, Russian Federation
| | - Zahed Allahyari
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center, 3 Nobel Street, Moscow 143026, Russian Federation
- Moscow Institute of Physics and Technology , 9 Institutsky Lane, Dolgoprudny 141700, Russian Federation
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Antipina LY, Kvashnin AG, Sorokin PB, Chernozatonskii LA. The possible formation of a magnetic FeS 2 phase in the two-dimensional MoS 2 matrix. Phys Chem Chem Phys 2016; 18:26956-26959. [PMID: 27711520 DOI: 10.1039/c6cp05065d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The possibility of a FeS2 phase formation in the 2D MoS2 structure was investigated by an ab initio DFT approach. Various concentrations of FeS2 in MoS2 have been analyzed, and it is shown that the energy favorable structures of the Mo1-xFexS2 composition are in-plane hybrid phases, FeS2 and MoS2 domains. After increasing the Fe/Mo concentration ratio up to 0.68, a complete transformation of the whole structure is predicted. We have found that the introduction of only a small amount of Fe atoms leads to a change in the electronic and magnetic properties of the film. An increase of the FeS2 nucleus size leads to the nearly monotonous increase of the magnetic moment governed by the exponential law.
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Affiliation(s)
- L Yu Antipina
- Emanuel Institute of Biochemical Physics, Russian Academy of Science, 4 Kosigin Street, Moscow, 119334, Russian Federation. and Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation and Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny, Moscow Region, 141700, Russian Federation
| | - A G Kvashnin
- Emanuel Institute of Biochemical Physics, Russian Academy of Science, 4 Kosigin Street, Moscow, 119334, Russian Federation. and Skolkovo Institute of Science and Technology (Skoltech), Skolkovo Innovation Center 143026, 3 Nobel Street, Moscow, Russian Federation
| | - P B Sorokin
- Emanuel Institute of Biochemical Physics, Russian Academy of Science, 4 Kosigin Street, Moscow, 119334, Russian Federation. and Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation and National University of Science and Technology MISiS, 4 Leninskiy prospekt, Moscow, 119049, Russian Federation
| | - L A Chernozatonskii
- Emanuel Institute of Biochemical Physics, Russian Academy of Science, 4 Kosigin Street, Moscow, 119334, Russian Federation.
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Abstract
Here we present a comprehensive investigation of various novel composite structures based on graphene (G) and molybdenum disulphide (MoS2) monolayers decorated by C60 fullerenes, which can be successfully applied in photovoltaics as a solar cell unit. Theoretical studies of the atomic structure, stability and electronic properties of the proposed G/C60, MoS2/C60 and G/MoS2/C60/G nanostructures were carried out. We show that making the G/MoS2/C60/G heterostructure from the 2D films considered here will lead to the appearance of particular properties suitable for application in photovoltaics due to the broad energetic region of high electronic density of states.
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Affiliation(s)
- Leonid A Chernozatonskii
- Emanuel Institute of Biochemical Physics of RAS, 119334, 4 Kosygin Street, Moscow, Russian Federation
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Abstract
On the basis of ab initio density functional calculations, we performed a comprehensive investigation of the general graphitization tendency in rocksalt-type structures. In this paper, we determine the critical slab thickness for a range of ionic cubic crystal systems, below which a spontaneous conversion from a cubic to a layered graphitic-like structure occurs. This conversion is driven by surface energy reduction. Using only fundamental parameters of the compounds such as the Allen electronegativity and ionic radius of the metal atom, we also develop an analytical relation to estimate the critical number of layers.
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Affiliation(s)
- A G Kvashnin
- Skolkovo Institute of Science and Technology (Skoltech), Skolkovo Innovation Center 143026, 3 Nobel Street, Moscow, Russian Federation
- Moscow Institute of Physics and Technology , 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
| | - E Y Pashkin
- Moscow Institute of Physics and Technology , 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
- Technological Institute for Superhard and Novel Carbon Materials , 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
| | - B I Yakobson
- Department of Materials Science and NanoEngineering and the Smalley Institute for Nanoscale Science and Technology, Rice University , Houston, Texas 77005, United States
| | - P B Sorokin
- Technological Institute for Superhard and Novel Carbon Materials , 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- National University of Science and Technology MISiS , 4 Leninskiy Prospekt, Moscow, 119049, Russian Federation
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Abstract
We present a theoretical study of current-voltage characteristics of different junctions of graphene nanoribbons. We considered isolated Y- and T-junctions of graphene nanoribbons (GNRs) with various geometry parameters and a graphene Y-junction in the graphane sheet. Our ab initio calculations based on the nonequilibrium Green's functions formalism displayed the influence of the geometry parameters of different ribbons on the I-V curves e.g. the shifting of zero voltage regions. We showed that not only the shape of the structure, but also the arrangement of electrodes attached to the structure will lead to changes in the transport properties.
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Affiliation(s)
- A G Kvashnin
- Technological Institute of Superhard and Novel Carbon Materials, 7a Centralnaya Street, 142190, Troitsk, Moscow, Russia. Moscow Institute of Physics and Technology, 9 Institutsky Lane, 141700, Dolgoprudny, Russia
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Abstract
We report theoretical analysis of the electronic flexoelectric effect associated with nanostructures of sp(2) carbon (curved graphene). Through the density functional theory calculations, we establish the universality of the linear dependence of flexoelectric atomic dipole moments on local curvature in various carbon networks (carbon nanotubes, fullerenes with high and low symmetry, and nanocones). The usefulness of such dependence is in the possibility to extend the analysis of any carbon systems with local deformations with respect to their electronic properties. This result is exemplified by exploring of flexoelectric effect in carbon nanocones that display large dipole moment, cumulative over their surface yet surprisingly scaling exactly linearly with the length, and with sine-law dependence on the apex angle, dflex ~ L sin(α). Our study points out the opportunity of predicting the electric dipole moment distribution on complex graphene-based nanostructures based only on the local curvature information.
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Affiliation(s)
- Alexander G Kvashnin
- †Department of Materials Science and NanoEngineering and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, United States
- ‡Technological Institute of Superhard and Novel Carbon Materials, Moscow 142190, Russian Federation
- §Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russian Federation
| | - Pavel B Sorokin
- †Department of Materials Science and NanoEngineering and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, United States
- ‡Technological Institute of Superhard and Novel Carbon Materials, Moscow 142190, Russian Federation
- ∥National University of Science and Technology MISiS, Moscow 119049, Russian Federation
| | - Boris I Yakobson
- †Department of Materials Science and NanoEngineering and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, United States
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Kvashnina YA, Kvashnin AG, Popov MY, Kulnitskiy BA, Perezhogin IA, Tyukalova EV, Chernozatonskii LA, Sorokin PB, Blank VD. Toward the Ultra-incompressible Carbon Materials. Computational Simulation and Experimental Observation. J Phys Chem Lett 2015; 6:2147-2152. [PMID: 26266517 DOI: 10.1021/acs.jpclett.5b00748] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The common opinion that diamond is the stiffest material is disproved by a number of experimental studies where the fabrication of carbon materials based on polymerized fullerenes with outstanding mechanical stiffness was reported. Here we investigated the nature of this unusual effect. We present a model constituted of compressed polymerized fullerite clusters implemented in a diamond matrix with bulk modulus B0 much higher than that of diamond. The calculated B0 value depends on the sizes of both fullerite grain and diamond environment and shows close correspondence with measured data. Additionally, we provide results of experimental study of atomic structure and mechanical properties of ultrahard carbon material supported the presented model.
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Affiliation(s)
- Yu A Kvashnina
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
| | - A G Kvashnin
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
| | - M Yu Popov
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
- §National University of Science and Technology MISiS, 4 Leninskiy prospekt, Moscow, 119049, Russian Federation
| | - B A Kulnitskiy
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
| | - I A Perezhogin
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
| | - E V Tyukalova
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
| | - L A Chernozatonskii
- ∥Emanuel Institute of Biochemical Physics, 4 Kosigina Street, Moscow, 119334, Russian Federation
| | - P B Sorokin
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
- §National University of Science and Technology MISiS, 4 Leninskiy prospekt, Moscow, 119049, Russian Federation
| | - V D Blank
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny, 141700, Russian Federation
- §National University of Science and Technology MISiS, 4 Leninskiy prospekt, Moscow, 119049, Russian Federation
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Kvashnin AG, Kvashnina OP, Kvashnin DG. Hydrogen adsorption study. Formation of quantum dots on graphene nanoribbons within tight-binding approach. Nanotechnology 2015; 26:175704. [PMID: 25835030 DOI: 10.1088/0957-4484/26/17/175704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Based on the tight-binding model, we investigate the formation process of quantum dots onto graphene nanoribbons (GNRs) by the sequential adsorption of hydrogen atoms onto the ribbon's surface. We define the difference between hydrogenation processes onto the surface of zigzag (ZGNR) and armchair graphene nanoribbons (AGNR) by calculating the binding energies with respect to the energy of isolated hydrogen atoms for all considered structures.
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Affiliation(s)
- Alexander G Kvashnin
- Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, 142190, Russia. Moscow Institute of Physics and Technology, 141700, 9 Institutskii line, Dolgoprudny, Moscow Region, Russia
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Sorokin PB, Kvashnin AG, Zhu Z, Tománek D. Spontaneous graphitization of ultrathin cubic structures: a computational study. Nano Lett 2014; 14:7126-7130. [PMID: 25384500 DOI: 10.1021/nl503673q] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Results based on ab initio density functional calculations indicate that cubic diamond, boron nitride, and many other cubic structures including rocksalt share a general graphitization tendency in ultrathin films terminated by close-packed (111) surfaces. Whereas such compounds often show an energy preference for cubic rather than layered atomic arrangements in the bulk, the surface energy of layered systems is commonly lower than that of their cubic counterparts. We determine the critical slab thickness for a range of systems, below which a spontaneous conversion from a cubic to a layered graphitic structure occurs, driven by surface energy reduction in surface-dominated structures.
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Affiliation(s)
- Pavel B Sorokin
- Physics and Astronomy Department, Michigan State University , East Lansing, Michigan 48824, United States
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Abstract
We applied the ab initio approach to evaluate the stability and physical properties of the nanometer-thickness NaCl layered films and found that the rock salt films with a (111) surface become unstable with thickness below 1 nm and spontaneously split to graphitic-like films for reducing the electrostatic energy penalty. The observed sodium chloride graphitic phase displays an uncommon atomic arrangement and exists only as nanometer-thin quasi-two-dimensional films. The graphitic bulk counterpart is unstable and transforms to another hexagonal wurtzite NaCl phase that locates in the negative-pressure region of the phase diagram. It was found that the layers in the graphitic NaCl film are weakly bounded with each other with a binding energy order of 0.1 eV per stoichiometry unit. The electronic band gap of the graphitic NaCl displays an unusual nonmonotonic quantum confinement response.
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Affiliation(s)
- Alexander G Kvashnin
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russian Federation
- §Emanuel Institute of Biochemical Physics, 4 Kosigina Street, Moscow 119334, Russian Federation
| | - Pavel B Sorokin
- †Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russian Federation
- §Emanuel Institute of Biochemical Physics, 4 Kosigina Street, Moscow 119334, Russian Federation
- ∥National University of Science and Technology MISiS, 4 Leninskiy Prospekt, Moscow 119049, Russian Federation
| | - David Tománek
- ⊥Physics and Astronomy Department, Michigan State University, East Lansing, Michigan 48824, United States
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Sun Y, Kvashnin AG, Sorokin PB, Yakobson BI, Billups WE. Radiation-Induced Nucleation of Diamond from Amorphous Carbon: Effect of Hydrogen. J Phys Chem Lett 2014; 5:1924-8. [PMID: 26273874 DOI: 10.1021/jz5007912] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Electron irradiation of anthracite functionalized by dodecyl groups leads to recrystallization of the carbon network into diamonds. The diamonds range in size from ∼2 to ∼10 nm and exhibit {111} spacing of 2.1 Å. A bulk process consistent with bias-enhanced nucleation is proposed in which the dodecyl group provides hydrogen during electron irradiation. Recrystallization into diamond occurs in the hydrogenated graphitic subsurface layers. Unfunctionalized anthracite could not be converted into diamond during electron irradiation. The dependence of the phase transition pressure on cluster size was estimated, and it was found that diamond particles with a radius up to 20 nm could be formed.
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Affiliation(s)
- Yanqiu Sun
- †Department of Chemistry, Rice University, 6100 Main Street, Houston, Texas 77005, United States
- ‡The Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, 6100 Main Street, Houston, Texas 77005, United States
| | - Alexander G Kvashnin
- †Department of Chemistry, Rice University, 6100 Main Street, Houston, Texas 77005, United States
- §Department of Mechanical Engineering and Materials Science, Rice University, 6100 Main Street, Houston, Texas 77005, United States
- ∥Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, Russia 142190
- ⊥Moscow Institute of Physics and Technology (State University), 9 Institutsky Lane, Dolgoprudny, Russia 141700
| | - Pavel B Sorokin
- ∥Technological Institute for Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow, Russia 142190
- ⊥Moscow Institute of Physics and Technology (State University), 9 Institutsky Lane, Dolgoprudny, Russia 141700
- #Emanuel Institute of Biochemical Physics RAS, 4 Kosigin Street, Moscow, Russia 119334
| | - Boris I Yakobson
- †Department of Chemistry, Rice University, 6100 Main Street, Houston, Texas 77005, United States
- §Department of Mechanical Engineering and Materials Science, Rice University, 6100 Main Street, Houston, Texas 77005, United States
| | - W E Billups
- †Department of Chemistry, Rice University, 6100 Main Street, Houston, Texas 77005, United States
- ‡The Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, 6100 Main Street, Houston, Texas 77005, United States
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Kvashnin AG, Chernozatonskii LA, Yakobson BI, Sorokin PB. Phase diagram of quasi-two-dimensional carbon, from graphene to diamond. Nano Lett 2014; 14:676-681. [PMID: 24437392 DOI: 10.1021/nl403938g] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We explore how a few-layer graphene can undergo phase transformation into thin diamond film under reduced or no pressure, if the process is facilitated by hydrogenation of the surfaces. Such a "chemically induced phase transition" is inherently nanoscale phenomenon, when the surface conditions directly affect thermodynamics, and the transition pressure depends greatly on film thickness. For the first time we obtain, by ab initio computations of the Gibbs free energy, a phase diagram (P, T, h) of quasi-two-dimensional carbon-diamond film versus multilayered graphene. It describes accurately the role of film thickness h and shows the feasibility of creating novel quasi-two-dimensional materials. Further, the role of finite diameter of graphene flakes and possible formation of the diamond films with the (110) surface are described as well.
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Affiliation(s)
- Alexander G Kvashnin
- Department of Mechanical Engineering & Materials Science and the Smalley Institute for Nanoscale Science and Technology, Rice University , Houston, Texas 77005, United States
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Abstract
We investigate the properties of potentially the stiffest quasi-2-D films with lonsdaleite structure. Using a combination of ab initio and empirical potential approaches, we analyze the elastic properties of lonsdaleite films in both elastic and inelastic regimes and compare them with graphene and diamond films. We review possible fabrication methods of lonsdaleite films using the pure nanoscale "bottom-up" paradigm: by connecting carbon layers in multilayered graphene. We propose the realization of this method in two ways: by applying direct pressure and by using the recently proposed chemically induced phase transition. For both cases, we construct the phase diagrams depending on temperature, pressure, and film thickness. Finally, we consider the electronic properties of lonsdaleite films and establish the nonlinear dependence of the band gap on the films' thicknesses and their lower effective masses in comparison with bulk crystal.
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Affiliation(s)
- Alexander G Kvashnin
- †Technological Institute of Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny 141700, Russian Federation
| | - Pavel B Sorokin
- †Technological Institute of Superhard and Novel Carbon Materials, 7a Centralnaya Street, Troitsk, Moscow 142190, Russian Federation
- ‡Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny 141700, Russian Federation
- ∥National University of Science and Technology "MISIS", Leninsky Avenue 4, Moscow 119049, Russian Federation
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Song L, Ci L, Lu H, Sorokin PB, Jin C, Ni J, Kvashnin AG, Kvashnin DG, Lou J, Yakobson BI, Ajayan PM. Large scale growth and characterization of atomic hexagonal boron nitride layers. Nano Lett 2010; 10:3209-15. [PMID: 20698639 DOI: 10.1021/nl1022139] [Citation(s) in RCA: 936] [Impact Index Per Article: 66.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Hexagonal boron nitride (h-BN), a layered material similar to graphite, is a promising dielectric. Monolayer h-BN, so-called "white graphene", has been isolated from bulk BN and could be useful as a complementary two-dimensional dielectric substrate for graphene electronics. Here we report the large area synthesis of h-BN films consisting of two to five atomic layers, using chemical vapor deposition. These atomic films show a large optical energy band gap of 5.5 eV and are highly transparent over a broad wavelength range. The mechanical properties of the h-BN films, measured by nanoindentation, show 2D elastic modulus in the range of 200-500 N/m, which is corroborated by corresponding theoretical calculations.
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Affiliation(s)
- Li Song
- Department of Mechanical Engineering & Materials Science, Rice University, Houston, Texas 77005, USA
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Sorokin PB, Kvashnin DG, Kvashnin AG, Avramov PV, Chernozatonskii LA. Theoretical study of elastic properties of SiC nanowires of different shapes. J Nanosci Nanotechnol 2010; 10:4992-4997. [PMID: 21125840 DOI: 10.1166/jnn.2010.2424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The atomic structure and elastic properties of silicon carbide nanowires of different shapes and effective sizes were studied using density functional theory and classical molecular mechanics. Upon surface relaxation, surface reconstruction led to the splitting of the wire geometry, forming both hexagonal (surface) and cubic phases (bulk). The behavior of the pristine SiC wires under compression and stretching was studied and Young's moduli were obtained. For Y-shaped SiC nanowires the effective Young's moduli and behavior in inelastic regime were elucidated.
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Affiliation(s)
- Pavel B Sorokin
- Siberian Federal University, 79 Svobodny av., Krasnoyarsk 660041, Russian Federation
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Sorokin PB, Kvashnin AG, Kvashnin DG, Filicheva JA, Avramov PV, Fedorov AS, Chernozatonskii LA. Theoretical study of atomic structure and elastic properties of branched silicon nanowires. ACS Nano 2010; 4:2784-2790. [PMID: 20411911 DOI: 10.1021/nn9018027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The atomic structure and elastic properties of Y-shaped silicon nanowires of "fork"- and "bough"-types were theoretically studied, and effective Young moduli were calculated using Tersoff interatomic potential. The oscillation of fork Y-type branched nanowires with various branch lengths and diameters was studied. In the final stages of the bending, the formation of new bonds between different parts of the wires was observed. It was found that the stiffness of the nanowires is comparable with the stiffness of Y-shaped carbon nanotubes.
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Affiliation(s)
- Pavel B Sorokin
- Siberian Federal University, 79 Svobodny Avenue, Krasnoyarsk, 660041 Russian Federation.
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