1
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Liu B, Allison W, Peng B, Avidor N, Monserrat B, Jardine AP. Distinguishing Quasiparticle-Phonon Interactions by Ultrahigh-Resolution Lifetime Measurements. PHYSICAL REVIEW LETTERS 2024; 132:176202. [PMID: 38728725 DOI: 10.1103/physrevlett.132.176202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 01/22/2024] [Accepted: 03/22/2024] [Indexed: 05/12/2024]
Abstract
We present a determination of quasiparticle-phonon interaction strengths at surfaces through measurements of phonon spectra with ultrahigh energy resolution. The lifetimes of low energy surface phonons on a pristine Ru(0001) surface were determined over a wide range of temperatures and an analysis of the temperature dependence enables us to attribute separate contributions from electron-phonon interactions, phonon-phonon interactions, and defect-phonon interactions. Strong electron-phonon interactions are evident at all temperatures and we show they dominate over phonon-phonon interactions below 400 K.
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Affiliation(s)
- Boyao Liu
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - William Allison
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Bo Peng
- TCM Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Nadav Avidor
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Bartomeu Monserrat
- TCM Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| | - Andrew P Jardine
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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2
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Cravero R, Tlili A, Paterson J, Tomelleri M, Marcello P, Debord R, Pailhès S, Bourgeois O, Hippert F, Le Qui D, Raty JY, Noe P, Giordano VM. Glass-Like Phonon Dynamics and Thermal Transport in a GeTe Nano-Composite at Low Temperature. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2310209. [PMID: 38634392 DOI: 10.1002/smll.202310209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/29/2024] [Indexed: 04/19/2024]
Abstract
In this work, the experimental evidence of glass-like phonon dynamics and thermal conductivity in a nanocomposite made of GeTe and amorphous carbon is reported, which is of interest for microelectronics, and specifically phase change memories. It is shown that, the total thermal conductivity is reduced by a factor of three at room temperature with respect to pure GeTe, due to the reduction of both electronic and phononic contributions. This latter, similarly to glasses, is small and weakly increasing with temperature between 100 and 300 K, indicating a mostly diffusive thermal transport and reaching a value of 0.86(7) Wm-1K-1 at room temperature. A thorough investigation of the nanocomposite's phonon dynamics reveals the appearance of an excess intensity in the low energy vibrational density of states, reminiscent of the Boson peak in glasses. These features can be understood in terms of an enhanced phonon scattering at the interfaces, due to the presence of elastic heterogeneities, at wavelengths in the 2-20 nm range. The findings confirm recent simulation results on crystalline/amorphous nanocomposites and open new perspectives in phonon and thermal engineering through the direct manipulation of elastic heterogeneities.
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Affiliation(s)
- R Cravero
- Institute of Light and Matter, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne cedex, F-69622, France
- Institut NEEL, CNRS, Université Grenoble Alpes, 25 avenue des Martyrs, Grenoble, F-38042, France
| | - A Tlili
- Institute of Light and Matter, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne cedex, F-69622, France
| | - J Paterson
- CEA, LETI, Université Grenoble Alpes, Grenoble, 38000, France
| | - M Tomelleri
- CEA, LETI, Université Grenoble Alpes, Grenoble, 38000, France
| | - P Marcello
- Institute of Light and Matter, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne cedex, F-69622, France
| | - R Debord
- Institute of Light and Matter, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne cedex, F-69622, France
| | - S Pailhès
- Institute of Light and Matter, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne cedex, F-69622, France
| | - O Bourgeois
- Institut NEEL, CNRS, Université Grenoble Alpes, 25 avenue des Martyrs, Grenoble, F-38042, France
| | - F Hippert
- CNRS, Grenoble INP, LMGP, Université Grenoble Alpes, Grenoble, F-38000, France
| | - D Le Qui
- FNRS and CESAM, Université de Liége, Sart-Tilman, 4000, Belgique
| | - J-Y Raty
- FNRS and CESAM, Université de Liége, Sart-Tilman, 4000, Belgique
| | - P Noe
- CEA, LETI, Université Grenoble Alpes, Grenoble, 38000, France
| | - V M Giordano
- Institute of Light and Matter, UMR5306 Université Lyon 1-CNRS, Université de Lyon, Villeurbanne cedex, F-69622, France
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3
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Viennois R, Debord R, Moll A, Legrand V, Beaudhuin M, Fréty N, Pailhès S. Stability and Physical Properties of Metastable Ba-Si Clathrates. Inorg Chem 2024; 63:5541-5551. [PMID: 38475716 DOI: 10.1021/acs.inorgchem.3c04520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
In the present study, we have investigated the stability of different Ba-Si clathrates with pressure and temperature using DFT calculations and studied the stability of type I Ba8Si46 and type IX Ba24Si100 clathrates using high pressure─high temperature synthesis technique, calorimetry, and diffraction experiments. When increasing pressure, the type I Ba8Si46 clathrate and BaSi6 become more stable. In good qualitative agreement with experiments, the type IX Ba24Si100 clathrate becomes stable at a pressure of 1-2 GPa thanks to the pressure and thermal effect of both electronic and vibrational contributions. One can notice that the presence of Ba in the cages of type IX clathrate increases significantly the stability and the mechanical properties of type IX clathrate. We have determined the P-T existence domain of type IX Ba24Si100 clathrate from ex situ experiments, which was confirmed by in situ synchrotron X-ray experiments. At room pressure and under an oxidizing atmosphere, the type I Ba8Si46 and the type IX Ba24Si100 clathrates are stable up to about 560 °C and up to about 600 °C, respectively. The thermoelectric properties of type IX Ba24Si100 are also reported.
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Affiliation(s)
- Romain Viennois
- ICGM, Univ Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | - Régis Debord
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex, France
| | - Adrien Moll
- ICGM, Univ Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | - Vincent Legrand
- ICGM, Univ Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | | | - Nicole Fréty
- ICGM, Univ Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | - Stéphane Pailhès
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex, France
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4
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Liu B, Kelsall J, Ward DJ, Jardine AP. Experimental Characterization of Defect-Induced Phonon Lifetime Shortening. PHYSICAL REVIEW LETTERS 2024; 132:056202. [PMID: 38364135 DOI: 10.1103/physrevlett.132.056202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/18/2023] [Accepted: 12/15/2023] [Indexed: 02/18/2024]
Abstract
We present the first direct experimental measurement of defect-induced lifetime shortening of acoustic surface phonons. Defects are found to contribute a temperature-independent component to the linewidths of Rayleigh wave phonons on a Ni(111) surface. We also characterized the increase in phonon scattering with both surface defect density and phonon wave vector. A quantitative estimate of the scattering rate between phonon modes and surface line defects is extracted from the experimental data for the first time.
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Affiliation(s)
- Boyao Liu
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Jack Kelsall
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - David J Ward
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Andrew P Jardine
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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5
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Salamakha L, Sologub O, Stöger B, Giester G, Rogl PF, Michor H, Bauer E. Electronic and Structural Properties of MPt xB 6-2x (M = Y, Yb): Structural Disorder in an Octahedral Boron Framework. Inorg Chem 2023; 62:19164-19177. [PMID: 37948347 PMCID: PMC10685457 DOI: 10.1021/acs.inorgchem.3c01526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/05/2023] [Accepted: 10/18/2023] [Indexed: 11/11/2023]
Abstract
Two new ternary platinum borides, YPtxB6-2x and YbPtxB6-2x, were obtained by argon-arc melting of the elements followed by annealing at 780 °C (750 °C). The structures of these compounds combine the fragments of CaB6- and AuCu3-type structures [space group Pm3̅m; x = 1.15, a = 4.0550(4) Å and x = 1.34, a = 4.0449(2) Å for YPtxB6-2x and YbPtxB6-2x, respectively; single-crystal X-ray diffraction]. Two possible variants of B/Pt ordering (space group P4/mmm) were created via a group-subgroup approach targeting the derived stoichiometry. The architecture of the type-I YPtxB6-2x structure model (a' = a, b' = b, c' = c) combines the 4.82 boron nets alternating with the layers of Y and Pt; the type-II YPtxB6-2x structure model (a' = 2a, b' = 2b, c' = c) exhibits columns of linked [B24] truncated cubes filled with Y running along the c axis. The striking features of both structural models are [B4Pt2] octahedra. The structural similarities with hitherto reported structures (YB2C2, M2Ni21B20, MNi21B20, and ErNiB4) were drawn supporting the verity of these models. A chemical bonding analysis for type-I and type-II YPtxB6-2x based on electron localization function distribution revealed a two-center interaction forming the 4.82 boron nets for type-I YPtxB6-2x and a covalent bonding within [B4Pt2] octahedra as well as a two-center interaction for B-B intraoctahedral bonds for type-II YPtxB6-2x. Analysis of Bader charges revealed the cationic character of the yttrium atoms. The interactions for nondistorted areas of the structures agree well with the bonding picture calculated for constituent building structures, YB6 and YPt3. Electronic structure calculations predict YPtxB6-2x to be a metal with the density of states of around N(EF) = 1 states eV-1 f.u.-1. The exploration of the Y-Pt-B system in the relevant concentration range elucidated the homogeneity field of YPtxB6-2x (0.90 ≤ x ≤ 1.40) and revealed the existence of three more ternary phases at 780 °C: YPt2B (space group P6222), YPt3B (space group P4mm), and YPt5B2 (space group C2/m).
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Affiliation(s)
- Leonid Salamakha
- Institute
of Solid State Physics, TU Wien, A-1040 Vienna, Austria
- Department
of Physics of Metals, L’viv National
University, 79000 L’viv, Ukraine
| | - Oksana Sologub
- Institute
of Solid State Physics, TU Wien, A-1040 Vienna, Austria
| | | | - Gerald Giester
- Institute
of Mineralogy and Crystallography, University
of Vienna, A-1090 Vienna, Austria
| | - Peter F. Rogl
- Institute
of Materials Chemistry, University of Vienna, A-1090 Vienna, Austria
| | - Herwig Michor
- Institute
of Solid State Physics, TU Wien, A-1040 Vienna, Austria
| | - Ernst Bauer
- Institute
of Solid State Physics, TU Wien, A-1040 Vienna, Austria
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6
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de Boissieu M. A deeper look into argyrodite phonons. NATURE MATERIALS 2023; 22:931-932. [PMID: 37524818 DOI: 10.1038/s41563-023-01605-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Affiliation(s)
- M de Boissieu
- Université Grenoble Alpes, CNRS, Grenoble INP-UGA, SIMaP, Grenoble, France.
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7
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K E V, Kumar Das S, Padhan P. Lattice thermal conductivity of topological insulator Bi 2Se 3 nanocrystals: comparison from theoretical and experimental. Phys Chem Chem Phys 2023; 25:13577-13586. [PMID: 37139687 DOI: 10.1039/d3cp00515a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Lattice thermal conductivity (κL) calculations using the Wiedemann-Franz law involve electrical conductivity, which introduces an error in the actual value of κL. We have adopted a non-contact measurement technique and calculated the κL from the temperature and power-dependent Raman spectra of the Bi2Se3 nanocrystals with truncated hexagon plate morphology stabilized in a hexagonal crystal structure. The hexagon plates of Bi2Se3 are 37 to 55 nm thick with lateral dimensions around 550 nm. These Bi2Se3 nanocrystals show three Raman lines, which agree with the theoretical prediction of A11g, E2g and A21g modes. Although the first-order thermal coefficient (-0.016) of Bi2Se3 nanocrystals is quite low, the room temperature κL ∼1.72 W m-1 K-1 is close to the value obtained from the simulation adopting a three-phonon process. The phonon lifetime of Bi2Se3 nanocrystals observed between ∼0.2 ps and 2 ps confirmed carrier-carrier thermalization with a small contribution from electron-electron and intraband electron-longitudinal-optical-phonon relaxation. The variations of phonon lifetime, Gruneisen parameter and κL of the mode frequencies outline the crucial role of the anharmonicity and acoustic-optical phonon scattering in reducing the κL of Bi2Se3. The non-contact measurements and relevant thermal property parameters open up exciting opportunities to address the anharmonic effects in other thermoelectric materials for obtaining a high figure of merit.
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Affiliation(s)
- Vipin K E
- Department of Physics, Nanoscale Physics Laboratory, Indian Institute of Technology Madras, Chennai 600036, India.
| | - Soumendra Kumar Das
- Department of Physics, Nanoscale Physics Laboratory, Indian Institute of Technology Madras, Chennai 600036, India.
| | - Prahallad Padhan
- Department of Physics, Nanoscale Physics Laboratory, Indian Institute of Technology Madras, Chennai 600036, India.
- Functional Oxides Research Group, Indian Institute of Technology Madras, Chennai 600036, India
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8
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Zhang J, Ishikawa D, Koza MM, Nishibori E, Song L, Baron AQR, Iversen BB. Dynamic Lone Pair Expression as Chemical Bonding Origin of Giant Phonon Anharmonicity in Thermoelectric InTe. Angew Chem Int Ed Engl 2023; 62:e202218458. [PMID: 36696593 DOI: 10.1002/anie.202218458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 01/26/2023]
Abstract
Loosely bonded ("rattling") atoms with s2 lone pair electrons are usually associated with strong anharmonicity and unexpectedly low thermal conductivity, yet their detailed correlation remains largely unknown. Here we resolve this correlation in thermoelectric InTe by combining chemical bonding analysis, inelastic X-ray and neutron scattering, and first principles phonon calculations. We successfully probe soft low-lying transverse phonons dominated by large In1+ z-axis motions, and their giant anharmonicity. We show that the highly anharmonic phonons arise from the dynamic lone pair expression with unstable occupied antibonding states induced by the covalency between delocalized In1+ 5s2 lone pair electrons and Te 5p states. This work pinpoints the microscopic origin of strong anharmonicity driven by rattling atoms with stereochemical lone pair activity, important for designing efficient materials for thermoelectric energy conversion.
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Affiliation(s)
- Jiawei Zhang
- Center for Integrated Materials Research, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, 8000, Aarhus, Denmark.,State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China
| | - Daisuke Ishikawa
- Materials Dynamics Laboratory, RIKEN SPring-8 Center, Sayo, 679-5148, Hyogo, Japan.,Precision Spectroscopy Division, SPring-8/JASRI, 1-1-1 Kouto, Sayo, 679-5198, Hyogo, Japan
| | - Michael M Koza
- Institut Laue Langevin, 71 avenue des Martyrs, 38042, Grenoble, France
| | - Eiji Nishibori
- Faculty of Pure and Applied Sciences and Tsukuba Research Center for Energy Materials Science (TREMS), University of Tsukuba, Tsukuba, 305-8571, Japan
| | - Lirong Song
- Center for Integrated Materials Research, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, 8000, Aarhus, Denmark
| | - Alfred Q R Baron
- Materials Dynamics Laboratory, RIKEN SPring-8 Center, Sayo, 679-5148, Hyogo, Japan.,Precision Spectroscopy Division, SPring-8/JASRI, 1-1-1 Kouto, Sayo, 679-5198, Hyogo, Japan
| | - Bo B Iversen
- Center for Integrated Materials Research, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, 8000, Aarhus, Denmark
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9
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Raturi M, Kaur A, Tyagi H, Bhakar M, Saini J, Kaur M, Sarkar AD, Hazra KS. Nanoscale probing of surface potential landscape at MoS 2/BP van der Waals p-n heterojunction. NANOTECHNOLOGY 2022; 34:095702. [PMID: 36541504 DOI: 10.1088/1361-6528/aca61a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
2D van der Waals heterostructure paves a path towards next generation semiconductor junctions for nanoelectronics devices in the post silicon era. Probing the band alignment at a real condition of such 2D contacts and experimental determination of its junction parameters is necessary to comprehend the charge diffusion and transport through such 2D nano-junctions. Here, we demonstrate the formation of the p-n junction at the MoS2/Black phosphorene (BP) interface and conduct a nanoscale investigation to experimentally measure the band alignment at real conditions by means of measuring the spatial distribution of built-in potential, built-in electric field, and depletion width using the Kelvin probe force microscopy (KPFM) technique. We show that optimization of lift scan height is critical for defining the depletion region of MoS2/BP with nanoscale precision using the KPFM technique. The variations in the built-in potential and built-in electric field with varying thicknesses of MoS2are revealed and calibrated.
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Affiliation(s)
- Mamta Raturi
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
| | - Arneet Kaur
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
| | - Himanshu Tyagi
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
| | - Monika Bhakar
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
| | - Jyoti Saini
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
| | - Manpreet Kaur
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
| | - Abir D Sarkar
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
| | - Kiran S Hazra
- Institute of Nano Science and Technology, Sector-81, Knowledge City, SAS Nagar, Punjab 140306, India
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10
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Phonon behavior in a random solid solution: a lattice dynamics study on the high-entropy alloy FeCoCrMnNi. Nat Commun 2022; 13:7509. [PMID: 36473859 PMCID: PMC9726824 DOI: 10.1038/s41467-022-35125-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 11/20/2022] [Indexed: 12/12/2022] Open
Abstract
High-Entropy Alloys (HEAs) are a new family of crystalline random alloys with four or more elements in a simple unit cell, at the forefront of materials research for their exceptional mechanical properties. Their strong chemical disorder leads to mass and force-constant fluctuations which are expected to strongly reduce phonon lifetime, responsible for thermal transport, similarly to glasses. Still, the long range order would associate HEAs to crystals with a complex disordered unit cell. These two families of materials, however, exhibit very different phonon dynamics, still leading to similar thermal properties. The question arises on the positioning of HEAs in this context. Here we present an exhaustive experimental investigation of the lattice dynamics in a HEA, Fe20Co20Cr20Mn20Ni20, using inelastic neutron and X-ray scattering. We demonstrate that HEAs present unique phonon dynamics at the frontier between fully disordered and ordered materials, characterized by long-propagating acoustic phonons in the whole Brillouin zone.
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11
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Chahal S, Prabhudessai AG, Shekhawat R, Vinoth S, Ramesh K. Structure-property relationships in critically connected (GeTe 4) 100-x(As 2Se 3) x glasses. Dalton Trans 2022; 51:12100-12113. [PMID: 35903976 DOI: 10.1039/d2dt01969h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thermal, optical, mechanical and structural studies were carried out on glasses in the pseudo-binary joint GeTe4-As2Se3 prepared by a melt quenching method. (GeTe4)100-x(As2Se3)x glasses in the entire composition range of 0 ≤ x ≤ 100 have an average coordination number (Zav) = 2.4, where the glass forming ability is found to be maximum. In general, for Zav ≤ 2.4, the glass transition is found to be dominated by the network connectivity and the chemical composition effects are minimal. Although Zav of Ge20Te80 (GeTe4) and As2Se3 (As40Se60) is 2.4, GeTe4 is a poor glass former and As2Se3 is an excellent glass former. The glass-forming ability is expected to increase with the addition of As2Se3. Surprisingly, the glass forming ability is found to decrease with the initial addition of As2Se3 and then shows an increasing trend. Glass transition (Tg) shows a large variation from 175 °C for x = 0 to 108 °C for x = 30. Based on the variation in the properties, the tie-line can be divided into three regions: region I (0 ≤ x ≤ 20) where Tg shows a decreasing trend, region II (25 ≤ x ≤ 55) where Tg remains almost constant and region III (60 ≤ x ≤ 100) where Tg shows an increasing trend. Hardness measurement also shows a similar trend in the three regions. Thermal stability shows a continuous increase with the increase of As2Se3. The fragility index varies between 15 and 30 for all these glasses except for x = 0 (GeTe4) indicating the strong nature of the melts containing As2Se3. Raman studies indicate that the glassy network is dominated mainly by GeTe(4/2) in region I and in region III the network is dominated by AsSe(3/2) based structures. Glasses in region II are found to be dominated by AsTe3/2 based structures. This study brings out the dominance of chemical composition effects over the network connectivity in a critically coordinated network. These glasses are also found to transmit IR light up to 18 μm and offer a wide composition range to prepare bulk glasses to be useful for infrared applications.
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Affiliation(s)
- Shweta Chahal
- Department of Physics, Indian Institute of Science, Bangalore 560012, India.
| | | | - Roopali Shekhawat
- Department of Physics, Indian Institute of Science, Bangalore 560012, India.
| | - S Vinoth
- Department of Physics, Indian Institute of Science, Bangalore 560012, India.
| | - K Ramesh
- Department of Physics, Indian Institute of Science, Bangalore 560012, India.
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12
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Cherniushok O, Cardoso-Gil R, Parashchuk T, Knura R, Grin Y, Wojciechowski KT. Lone-Pair-Like Interaction and Bonding Inhomogeneity Induce Ultralow Lattice Thermal Conductivity in Filled β-Manganese-Type Phases. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:6389-6401. [PMID: 35937497 PMCID: PMC9344398 DOI: 10.1021/acs.chemmater.2c00915] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Finding a way to interlink heat transport with the crystal structure and order/disorder phenomena is crucial for designing materials with ultralow lattice thermal conductivity. Here, we revisit the crystal structure and explore the thermoelectric properties of several compounds from the family of the filled β-Mn-type phases M 2/n n+Ga6Te10 (M = Pb, Sn, Ca, Na, Na + Ag). The strongly disturbed thermal transport observed in the investigated materials originates from a three-dimensional Te-Ga network with lone-pair-like interactions, which results in large variations of the Ga-Te and M-Te interatomic distances and substantial anharmonic effects. In the particular case of NaAgGa6Te10, the additional presence of different cations leads to bonding inhomogeneity and strong structural disorder, resulting in a dramatically low lattice thermal conductivity (∼0.25 Wm-1 K-1 at 298 K), being the lowest among the reported β-Mn-type phases. This study offers a way to develop materials with ultralow lattice thermal conductivity by considering bonding inhomogeneity and lone-pair-like interactions.
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Affiliation(s)
- Oleksandr Cherniushok
- Thermoelectric
Research Laboratory, Department of Inorganic Chemistry, Faculty of
Materials Science and Ceramics, AGH University
of Science and Technology, Mickiewicza Ave. 30, 30-059 Krakow, Poland
| | - Raul Cardoso-Gil
- Max-Planck-Institut
für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - Taras Parashchuk
- Thermoelectric
Research Laboratory, Department of Inorganic Chemistry, Faculty of
Materials Science and Ceramics, AGH University
of Science and Technology, Mickiewicza Ave. 30, 30-059 Krakow, Poland
| | - Rafal Knura
- Thermoelectric
Research Laboratory, Department of Inorganic Chemistry, Faculty of
Materials Science and Ceramics, AGH University
of Science and Technology, Mickiewicza Ave. 30, 30-059 Krakow, Poland
- Department
of Science, Graduate School of Science and Technology, Kumamoto University, 2 Chome-39-1 Kurokami, Chuo Ward, 860-8555 Kumamoto, Japan
| | - Yuri Grin
- Max-Planck-Institut
für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - Krzysztof T. Wojciechowski
- Thermoelectric
Research Laboratory, Department of Inorganic Chemistry, Faculty of
Materials Science and Ceramics, AGH University
of Science and Technology, Mickiewicza Ave. 30, 30-059 Krakow, Poland
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13
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Levytskyi V, Carrillo-Cabrera W, Akselrud L, Kundys B, Leithe-Jasper A, Gumeniuk R. Superconductivity of structurally disordered Y 5Ir 6Sn 18. Dalton Trans 2022; 51:10036-10046. [PMID: 35723520 DOI: 10.1039/d2dt01353c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structural and physical properties of Y5Ir6Sn18 grown from Sn-flux as large single crystals are studied. Y5Ir6Sn18 crystallizes with a unique structure [space group Fm3̄m, a = 13.7706(1) Å], which is characterized by a strong disorder. A transmission electron microscopy (TEM) study indicated that the structural model of Y5Ir6Sn18 obtained from X-ray diffraction methods is an average description of a complex intergrowth of domains with different structural arrangements. The studied stannide is a type-II superconductor with a critical temperature Tc = 2.1 K, a rather weak electron-phonon coupling and conventional s-wave BCS-like mechanisms. Performed theoretical electronic band structure calculations indicated the inconsistency of an idealized structural model earlier reported for Y5Ir6Sn18.
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Affiliation(s)
- Volodymyr Levytskyi
- Institut für Experimentelle Physik, TU Bergakademie Freiberg, Leipziger Straße 23, 09596 Freiberg, Germany.
| | - Wilder Carrillo-Cabrera
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Lev Akselrud
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany.,Ivan Franko National University of Lviv, Kyryla and Mefodiya Str. 6, UA-79005, Lviv, Ukraine
| | - Bohdan Kundys
- Institute de Physique et de Chemie des Matériaux de Strasbourg, UMR 7504 CNRS-ULP, 23, rue du Loess, BP 43, F67034 Strasbourg Cedex 2, France
| | - Andreas Leithe-Jasper
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Roman Gumeniuk
- Institut für Experimentelle Physik, TU Bergakademie Freiberg, Leipziger Straße 23, 09596 Freiberg, Germany.
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14
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Thermoelectric properties and band structures of vacancy-containing Sn-based clathrates K8Sn44−Ge. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.122471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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15
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Dutta M, Sarkar D, Biswas K. Intrinsically ultralow thermal conductive inorganic solids for high thermoelectric performance. Chem Commun (Camb) 2021; 57:4751-4767. [PMID: 33884387 DOI: 10.1039/d1cc00830g] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Thermoelectric materials which can convert heat energy to electricity rely on crystalline inorganic solid state compounds exhibiting low phonon transport (i.e. low thermal conductivity) without much inhibiting the electrical transport. Suppression of phonons traditionally has been carried out via extrinsic pathways, involving formation of point defects, foreign nanostructures, and meso-scale grains, but the incorporation of extrinsic substituents also influences the electrical properties. Crystalline materials with intrinsically low lattice thermal conductivity (κlat) provide an attractive paradigm as it helps in simplifying the complex interrelated thermoelectric parameters and allows us to focus largely on improving the electronic properties. In this feature article, we have discussed the chemical bonding and structural aspects in determining phonon transport through a crystalline material. We have outlined how the inherent material properties like lone pair, bonding anharmonicity, presence of intrinsic rattlers, ferroelectric instability, weak and rigid substructures, etc. influence in effectively suppressing the heat transport. The strategies summarized in this feature article should serve as a general guide to rationally design and predict materials with low κlat for potential thermoelectric applications.
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Affiliation(s)
- Moinak Dutta
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bangalore 560064, India.
| | - Debattam Sarkar
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bangalore 560064, India.
| | - Kanishka Biswas
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bangalore 560064, India. and School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bangalore 560064, India and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bangalore 560064, India
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16
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Zhang J, Liu Q, Liu KF, Tan WJ, Liu XC, Xia SQ. Sr 9Mg 4.45(1)Bi 9 and Sr 9Mg 4.42(1)Sb 9: Mg-Containing Zintl Phases with Low Thermal Conductivity. Inorg Chem 2021; 60:4026-4033. [PMID: 33635076 DOI: 10.1021/acs.inorgchem.1c00078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Zintl phases with nominal 9-4-9 formulas are very interesting for their potential applications as thermoelectric materials. However, the formation of such phases usually requires divalent transition metals, for example, Zn, Mn, and Cd, which are covalently bonded to the pnictogen atoms. In this report, for the first time, two Mg-containing compounds with such structures as Sr9Mg4.45(1)Bi9 and Sr9Mg4.42(1)Sb9 were synthesized and their structures were determined by the single-crystal X-ray diffraction method. Both title compounds crystallize in the orthorhombic space group Pnma and are isostructural with Ca9Mn4.41(1)Sb9, which features complex polyanion structures compared to the classical 9-4-9 phases. For Sr9Mg4.45(1)Bi9, its low thermal conductivity, combined with its high electrical conductivity and moderate Seebeck coefficient, leads to a decent figure of merit of 0.57 at 773 K, which obviously prevails in the unoptimized 9-4-9 phases. The discovery of such Mg-containing 9-4-9 phases is very significant, as the discovery not only enriches the structure map of the well-known 9-4-9 family but also provides very valuable thermoelectric candidates surely deserving of more in-depth investigation.
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Affiliation(s)
- Jian Zhang
- State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100, People's Republic of China
| | - Qian Liu
- State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100, People's Republic of China
| | - Ke-Feng Liu
- State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100, People's Republic of China
| | - Wen-Jie Tan
- School of Materials Science and Engineering, Shandong Jianzhu University, Jinan, Shandong 250101, People's Republic of China
| | - Xiao-Cun Liu
- School of Civil Engineering, Shandong Jiaotong University, Jinan, Shandong 250300, People's Republic of China
| | - Sheng-Qing Xia
- State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100, People's Republic of China
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17
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Dutta M, Samanta M, Ghosh T, Voneshen DJ, Biswas K. Evidence of Highly Anharmonic Soft Lattice Vibrations in a Zintl Rattler. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013923] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Moinak Dutta
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
| | - Manisha Samanta
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
| | - Tanmoy Ghosh
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
| | - David J. Voneshen
- ISIS Pulsed Neutron and Muon Source and Department of Physics Rutherford Appleton Laboratory Didcot OX11 0QX UK
- Royal Holloway University of London Egham TW20 0EX UK
| | - Kanishka Biswas
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
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18
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Cherniushok O, Cardoso-Gil R, Parashchuk T, Grin Y, Wojciechowski KT. Phase Equilibria and Thermoelectric Properties in the Pb–Ga–Te System in the Vicinity of the PbGa6Te10 Phase. Inorg Chem 2021; 60:2771-2782. [DOI: 10.1021/acs.inorgchem.0c03549] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Oleksandr Cherniushok
- Faculty of Materials Science and Ceramics, AGH University of Science and Technology, 30 Mickiewicza Avenue, Krakow 30-059, Poland
| | - Raul Cardoso-Gil
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, Dresden 01187, Germany
| | - Taras Parashchuk
- Lukasiewicz Research Network—Krakow Institute of Technology, 73 Zakopianska Street, Krakow 30-418, Poland
| | - Yuri Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, Dresden 01187, Germany
| | - Krzysztof T. Wojciechowski
- Faculty of Materials Science and Ceramics, AGH University of Science and Technology, 30 Mickiewicza Avenue, Krakow 30-059, Poland
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19
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Dutta M, Samanta M, Ghosh T, Voneshen DJ, Biswas K. Evidence of Highly Anharmonic Soft Lattice Vibrations in a Zintl Rattler. Angew Chem Int Ed Engl 2020; 60:4259-4265. [DOI: 10.1002/anie.202013923] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Indexed: 11/06/2022]
Affiliation(s)
- Moinak Dutta
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
| | - Manisha Samanta
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
| | - Tanmoy Ghosh
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
| | - David J. Voneshen
- ISIS Pulsed Neutron and Muon Source and Department of Physics Rutherford Appleton Laboratory Didcot OX11 0QX UK
- Royal Holloway University of London Egham TW20 0EX UK
| | - Kanishka Biswas
- New Chemistry Unit School of Advanced Materials and International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) Jakkur P.O. Bangalore 560064 India
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20
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Xia Y, Ozoliņš V, Wolverton C. Microscopic Mechanisms of Glasslike Lattice Thermal Transport in Cubic Cu_{12}Sb_{4}S_{13} Tetrahedrites. PHYSICAL REVIEW LETTERS 2020; 125:085901. [PMID: 32909770 DOI: 10.1103/physrevlett.125.085901] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/28/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
Materials based on cubic tetrahedrites (Cu_{12}Sb_{4}S_{13}) are useful thermoelectrics with unusual thermal and electrical transport properties, such as very low and nearly temperature-independent lattice thermal conductivity (κ_{L}). We explain the microscopic origin of the glasslike κ_{L} in Cu_{12}Sb_{4}S_{13} by explicitly treating anharmonicity up to quartic terms for both phonon energies and phonon scattering rates. We show that the strongly unstable phonon modes associated with trigonally coordinated Cu atoms are anharmonically stabilized above approximately 100 K and continue hardening with increasing temperature in accord with experimental data. This temperature-induced hardening effect reduces scattering of heat carrying acoustic modes by reducing the available phase space for three-phonon processes, thereby balancing the conventional ∝T increase in scattering due to phonon population and yielding nearly temperature-independent κ_{L}. Furthermore, we find that very strong phonon broadening leads to a qualitative breakdown of the conventional phonon-gas model and modify the dominant heat transport mechanism from the particlelike phonon wave packet propagation to incoherent contributions described by the off-diagonal terms in the heat-flux operator, which are typically prevailing in glasses and disordered crystals. Our work paves the way to a deeper understanding of glasslike thermal conductivity in complex crystals with strong anharmonicity.
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Affiliation(s)
- Yi Xia
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA
| | - Vidvuds Ozoliņš
- Department of Applied Physics, Yale University, New Haven, Connecticut 06511, USA
- Energy Sciences Institute, Yale University, West Haven, Connecticut 06516, USA
| | - Chris Wolverton
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA
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21
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Amon A, Svanidze E, Prots Y, Nicklas M, Burkhardt U, Ormeci A, Leithe-Jasper A, Grin Y. Y 4Be 33Pt 16- a non-centrosymmetric cage superconductor with multi-centre bonding in the framework. Dalton Trans 2020; 49:9362-9368. [PMID: 32584336 DOI: 10.1039/d0dt01374a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The new ternary compound Y4Be33Pt16 was prepared from elements by arc melting, and its crystal structure was determined from single-crystal X-ray diffraction data (space group I4[combining macron]3d, a = 13.4849(3) Å). The material is the first representative of a new structure type of complex intermetallic compounds and reveals a cage-like crystal structure. Analysis of chemical bonding by means of the electron localizabilty approach indicates ionic interaction of yttrium with the rest of the crystal structure, characteristic for cage compounds, in particular for clathrates. In contrast to the mostly two-centre bonding in the framework of clathrates, the new compound is characterized by a multi-centre interaction within the framework, caused by the demand of the valence electrons in the system. The non-centrosymmetric material enters the superconducting state at TC = 0.9 K.
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Affiliation(s)
- Alfred Amon
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, Dresden 01187, Germany
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22
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Liang SJ, Cheng B, Cui X, Miao F. Van der Waals Heterostructures for High-Performance Device Applications: Challenges and Opportunities. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1903800. [PMID: 31608514 DOI: 10.1002/adma.201903800] [Citation(s) in RCA: 108] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/22/2019] [Indexed: 06/10/2023]
Abstract
The discovery of two-dimensional (2D) materials with unique electronic, superior optoelectronic, or intrinsic magnetic order has triggered worldwide interest in the fields of material science, condensed matter physics, and device physics. Vertically stacking 2D materials with distinct electronic and optical as well as magnetic properties enables the creation of a large variety of van der Waals heterostructures. The diverse properties of the vertical heterostructures open unprecedented opportunities for various kinds of device applications, e.g., vertical field-effect transistors, ultrasensitive infrared photodetectors, spin-filtering devices, and so on, which are inaccessible in conventional material heterostructures. Here, the current status of vertical heterostructure device applications in vertical transistors, infrared photodetectors, and spintronic memory/transistors is reviewed. The relevant challenges for achieving high-performance devices are presented. An outlook into the future development of vertical heterostructure devices with integrated electronic and optoelectronic as well as spintronic functionalities is also provided.
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Affiliation(s)
- Shi-Jun Liang
- National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Bin Cheng
- National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xinyi Cui
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210046, China
| | - Feng Miao
- National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
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23
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Verchère A, Pailhès S, Le Floch S, Cottrino S, Debord R, Fantozzi G, Misra S, Candolfi C, Lenoir B, Daniele S, Mishra S. Optimum in the thermoelectric efficiency of nanostructured Nb-doped TiO 2 ceramics: from polarons to Nb-Nb dimers. Phys Chem Chem Phys 2020; 22:13008-13016. [PMID: 32478345 DOI: 10.1039/d0cp00652a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rutile is the most common and stable polymorph form of titanium oxide TiO2 at all temperatures. The doping of rutile TiO2 with a small amount of niobium is reknown for being responsible for a large increase of the electrical conductivity by several orders of magnitude, broadening its technological interest towards new emerging fields such as the thermoelectric conversion of waste heat. The electronic conduction has been found to be of a polaronic nature with strongly localized charges around the Ti3+ centers while, on the other side, the relatively high value of the thermal conductivity implies the existence of lattice heat carriers, i.e. phonons, with large mean free paths which makes the nanostructuration relevant for optimizing the thermoelectric efficiency. Here, the use of a high-pressure and high-temperature sintering technique has allowed to vary the grain size in rutile TiO2 pellets from 300 to 170 nm, leading to a significant reduction of the lattice thermal conductivity. The thermoelectric properties (electrical conductivity, Seebeck coefficient and thermal conductivity) of Nb-doped rutile nanostructured ceramics, namely NbxTi1-xO2 with x varying from 1 to 5%, are reported from room temperature to ∼900 K. With the incorporation of Nb, an optimum in the thermoelectric properties together with an anomaly on the tetragonal lattice constant c are observed for a concentration of ∼2.85%, which might be the fingerprint of the formation of short Nb dimers.
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Affiliation(s)
- Alexandre Verchère
- IRCELYON, Université Lyon1 - CNRS, UMR 5256, 2 Avenue Albert Einstein, 69626 Villeurbanne, France
| | - Stéphane Pailhès
- Institut Lumière Matière, Université Lyon1 - CNRS, UMR 5306, Université de Lyon, 69622 Villeurbanne, France.
| | - Sylvie Le Floch
- Institut Lumière Matière, Université Lyon1 - CNRS, UMR 5306, Université de Lyon, 69622 Villeurbanne, France.
| | - Sandrine Cottrino
- MATEIS, Insa-Université Lyon1 - CNRS, UMR 5510, INSA de Lyon, 69621 Villeurbanne, France
| | - Régis Debord
- Institut Lumière Matière, Université Lyon1 - CNRS, UMR 5306, Université de Lyon, 69622 Villeurbanne, France.
| | - Gilbert Fantozzi
- MATEIS, Insa-Université Lyon1 - CNRS, UMR 5510, INSA de Lyon, 69621 Villeurbanne, France
| | - Shantanu Misra
- Institut Jean Lamour, UMR 7198 CNRS - Université de Lorraine, 2 allée André Guinier-Campus ARTEM, BP 50840, 54011 Nancy Cedex, France
| | - Christophe Candolfi
- Institut Jean Lamour, UMR 7198 CNRS - Université de Lorraine, 2 allée André Guinier-Campus ARTEM, BP 50840, 54011 Nancy Cedex, France
| | - Bertrand Lenoir
- Institut Jean Lamour, UMR 7198 CNRS - Université de Lorraine, 2 allée André Guinier-Campus ARTEM, BP 50840, 54011 Nancy Cedex, France
| | - Stéphane Daniele
- C2P2, Université Lyon 1 - CPE Lyon - CNRS, UMR 5265, 43 Bvd du 11 Novembre 1918, 69616 Villeurbanne, France
| | - Shashank Mishra
- IRCELYON, Université Lyon1 - CNRS, UMR 5256, 2 Avenue Albert Einstein, 69626 Villeurbanne, France
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24
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Feig M, Akselrud L, Schnelle W, Dyadkin V, Chernyshov D, Ormeci A, Simon P, Leithe-Jasper A, Gumeniuk R. Crystal structure, chemical bonding, and electrical and thermal transport in Sc 5Rh 6Sn 18. Dalton Trans 2020; 49:6832-6841. [PMID: 32377645 DOI: 10.1039/d0dt00324g] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Single crystals of Sc5Rh6Sn18 were grown from Sn-flux. The crystal structure (SG: I41/acd, a = 13.5529(2) Å, c = 27.0976(7) Å) was studied by high-resolution X-ray diffraction on powder and single crystal material as well as by TEM. All methods confirm it to crystallize with a Sc5Ir6Sn18 (space group I41/acd) type structure. The performed structural studies also suggest the presence of local domains with a broken average translational symmetry. An analysis of the chemical bonding situation reveals highly polar covalent Sc2-Sn1, Sn-Rh and Sc2-Rh bonds, two- and three-centre bonds involving Sn-atoms as well as the ionic nature of Sc1 bonding. The thermopower of Sc5Rh6Sn18 is isotropic, small and negative (i.e. dominance of electron-like charge carriers). Due to structural disorder, the thermal conductivity is lower in comparison with regular metallic systems.
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Affiliation(s)
- Manuel Feig
- Institut für Experimentelle Physik, TU Bergakademie Freiberg, Leipziger Straße 23, 09596 Freiberg, Germany.
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25
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Luo Y, Yang X, Feng T, Wang J, Ruan X. Vibrational hierarchy leads to dual-phonon transport in low thermal conductivity crystals. Nat Commun 2020; 11:2554. [PMID: 32444680 PMCID: PMC7244571 DOI: 10.1038/s41467-020-16371-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 04/23/2020] [Indexed: 11/08/2022] Open
Abstract
Many low-thermal-conductivity (κL) crystals show intriguing temperature (T) dependence of κL: κL ∝ T-1 (crystal-like) at intermediate temperatures whereas weak T-dependence (glass-like) at high temperatures. It has been in debate whether thermal transport can still be described by phonons at the Ioffe-Regel limit. In this work, we propose that most phonons are still well defined for thermal transport, whereas they carry heat via dual channels: normal phonons described by the Boltzmann transport equation theory, and diffuson-like phonons described by the diffusion theory. Three physics-based criteria are incorporated into first-principles calculations to judge mode-by-mode between the two phonon channels. Case studies on La2Zr2O7 and Tl3VSe4 show that normal phonons dominate low temperatures while diffuson-like phonons dominate high temperatures. Our present dual-phonon theory enlightens the physics of hierarchical phonon transport as approaching the Ioffe-Regel limit and provides a numerical method that should be practically applicable to many materials with vibrational hierarchy.
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Affiliation(s)
- Yixiu Luo
- School of Mechanical Engineering and the Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Xiaolong Yang
- School of Mechanical Engineering and the Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Tianli Feng
- Energy and Transportation Science Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Jingyang Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Xiulin Ruan
- School of Mechanical Engineering and the Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA.
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Shen J, Xie T, Zhang L, Wang P, Fang Z. Si 2Ge: A New VII-Type Clathrate with Ultralow Thermal Conductivity and High Thermoelectric Property. Sci Rep 2020; 10:3068. [PMID: 32080248 PMCID: PMC7033159 DOI: 10.1038/s41598-020-59820-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 01/28/2020] [Indexed: 11/27/2022] Open
Abstract
Based on global particle-swarm optimization algorithm and density functional theory methods, we predicted an alloyed Si2Ge compond with body centered tetragonal type VII clathrate (space group I4/mmm) built by a truncated octahedron fromed by six quadrangles and eight hexagons ([4668]). Si2Ge clathrate is 0.06 eV/atom lower than VII Si clathrate and thermally stable up to 1000 K. It has an indirect band gap of 0.23 eV, high p-doping Seebeck coefficient and n-doping electrical conductivity. It owns a low lattice thermal conductivity of 0.28 W/mK at 300 K because of its weak bonding and strong anharmonic interaction of longitudinal acoustic and low-lying optical phonons. The moderate electronic transport properties together with low lattice thermal conductivity results in a high optimal thermoeletric performance value of 2.54 (1.49) at 800 (1000) K in n (p)-doped Si2Ge.
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Affiliation(s)
- Jinni Shen
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, 350108, China
- Key Laboratory of Eco-materials Advanced Technology, College of Materials Science and Engineering, Fuzhou University, Fuzhou, 350108, China
| | - Tianzhu Xie
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, 350108, China
| | - Longkun Zhang
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, 350108, China
| | - Ping Wang
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, 350108, China
| | - Zhenxing Fang
- Department of Physics, Zunyi Normal University, Zunyi, Guizhou, 563006, China.
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27
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Schwarz U, Castillo R, Hübner JM, Wosylus A, Prots Y, Bobnar M, Grin Y. The untypical high-pressure Zintl phase SrGe6. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2020. [DOI: 10.1515/znb-2019-0197] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
The binary strontium germanide SrGe6 was synthesized at high-pressure high-temperature conditions of approximately 10 GPa and typically 1400 K before quenching to ambient conditions. At ambient pressure, SrGe6 decomposes in a monotropic fashion at T = 680(10) K into SrGe2 and Ge, indicating its metastable character. Single-crystal X-ray diffraction data indicate that the compound SrGe6 adopts a new monoclinic structure type comprising a unique three-dimensional framework of germanium atoms with unusual cages hosting the strontium cations. Quantum chemical analysis of the chemical bonding shows that the framework consists of three- and four- bonded germanium atoms yielding the precise electron count Sr[(4bGe0]4[(3b)Ge−]2 in accordance with the 8 − N rule and the Zintl concept. Conflicting with that, a pseudo-gap in the electronic density of states appears clearly below the Fermi level, and elaborate bonding analysis reveals additional Sr–Ge interactions in the concave coordination polyhedron of the strontium atoms.
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Affiliation(s)
- Ulrich Schwarz
- Max-Planck-Institut für Chemische Physik fester Stoffe , Nöthnitzer Straße 40, 01187 Dresden , Germany
| | - Rodrigo Castillo
- Max-Planck-Institut für Chemische Physik fester Stoffe , Nöthnitzer Straße 40, 01187 Dresden , Germany
| | - Julia M. Hübner
- Max-Planck-Institut für Chemische Physik fester Stoffe , Nöthnitzer Straße 40, 01187 Dresden , Germany
| | - Aron Wosylus
- Max-Planck-Institut für Chemische Physik fester Stoffe , Nöthnitzer Straße 40, 01187 Dresden , Germany
| | - Yurii Prots
- Max-Planck-Institut für Chemische Physik fester Stoffe , Nöthnitzer Straße 40, 01187 Dresden , Germany
| | - Matej Bobnar
- Max-Planck-Institut für Chemische Physik fester Stoffe , Nöthnitzer Straße 40, 01187 Dresden , Germany
| | - Yuri Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe , Nöthnitzer Straße 40, 01187 Dresden , Germany
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Glensk A, Grabowski B, Hickel T, Neugebauer J, Neuhaus J, Hradil K, Petry W, Leitner M. Phonon Lifetimes throughout the Brillouin Zone at Elevated Temperatures from Experiment and Ab Initio. PHYSICAL REVIEW LETTERS 2019; 123:235501. [PMID: 31868491 DOI: 10.1103/physrevlett.123.235501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Indexed: 06/10/2023]
Abstract
We obtain phonon lifetimes in aluminium by inelastic neutron scattering experiments, by ab initio molecular dynamics, and by perturbation theory. At elevated temperatures significant discrepancies are found between experiment and perturbation theory, which disappear when using molecular dynamics due to the inclusion of full anharmonicity and the correct treatment of the multiphonon background. We show that multiple-site interactions are small and that local pairwise anharmonicity dominates phonon-phonon interactions, which permits an efficient computation of phonon lifetimes.
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Affiliation(s)
- Albert Glensk
- Max-Planck-Institut für Eisenforschung GmbH, 40237 Düsseldorf, Germany
- Laboratory for Multiscale Mechanics and Modeling (LAMMM) and Laboratory for Computational Science and Modelling (COSMO), Ecole Polytechnique Federale de Lausanne, 1015 Lausanne, Switzerland
| | - Blazej Grabowski
- Institute of Materials Science, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Tilmann Hickel
- Max-Planck-Institut für Eisenforschung GmbH, 40237 Düsseldorf, Germany
| | - Jörg Neugebauer
- Max-Planck-Institut für Eisenforschung GmbH, 40237 Düsseldorf, Germany
| | - Jürgen Neuhaus
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, 85748 Garching, Germany
| | - Klaudia Hradil
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, 85748 Garching, Germany
| | - Winfried Petry
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, 85748 Garching, Germany
| | - Michael Leitner
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, 85748 Garching, Germany
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29
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Thermoelectric and magnetic properties of rare earth borides: Boron cluster and layered compounds. J SOLID STATE CHEM 2019. [DOI: 10.1016/j.jssc.2019.03.046] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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30
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Synoradzki K, Ciesielski K, Veremchuk I, Borrmann H, Skokowski P, Szymański D, Grin Y, Kaczorowski D. Thermal and Electronic Transport Properties of the Half-Heusler Phase ScNiSb. MATERIALS 2019; 12:ma12101723. [PMID: 31137868 PMCID: PMC6566183 DOI: 10.3390/ma12101723] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 05/24/2019] [Accepted: 05/24/2019] [Indexed: 11/16/2022]
Abstract
Thermoelectric properties of the half-Heusler phase ScNiSb (space group F 4 ¯ 3m) were studied on a polycrystalline single-phase sample obtained by arc-melting and spark-plasma-sintering techniques. Measurements of the thermopower, electrical resistivity, and thermal conductivity were performed in the wide temperature range 2-950 K. The material appeared as a p-type conductor, with a fairly large, positive Seebeck coefficient of about 240 μV K-1 near 450 K. Nevertheless, the measured electrical resistivity values were relatively high (83 μΩm at 350 K), resulting in a rather small magnitude of the power factor (less than 1 × 10-3 W m-1 K-2) in the temperature range examined. Furthermore, the thermal conductivity was high, with a local minimum of about 6 W m-1 K-1 occurring near 600 K. As a result, the dimensionless thermoelectric figure of merit showed a maximum of 0.1 at 810 K. This work suggests that ScNiSb could be a promising base compound for obtaining thermoelectric materials for energy conversion at high temperatures.
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Affiliation(s)
- Karol Synoradzki
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P. O. Box 1410, 50-950 Wrocław, Poland.
| | - Kamil Ciesielski
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P. O. Box 1410, 50-950 Wrocław, Poland.
| | - Igor Veremchuk
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany.
| | - Horst Borrmann
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany.
| | - Przemysław Skokowski
- Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Poznań, Poland.
| | - Damian Szymański
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P. O. Box 1410, 50-950 Wrocław, Poland.
| | - Yuri Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany.
| | - Dariusz Kaczorowski
- Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P. O. Box 1410, 50-950 Wrocław, Poland.
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Kondo-like phonon scattering in thermoelectric clathrates. Nat Commun 2019; 10:887. [PMID: 30792390 PMCID: PMC6385256 DOI: 10.1038/s41467-019-08685-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 01/24/2019] [Indexed: 11/17/2022] Open
Abstract
Crystalline solids are generally known as excellent heat conductors, amorphous materials or glasses as thermal insulators. It has thus come as a surprise that certain crystal structures defy this paradigm. A prominent example are type-I clathrates and other materials with guest-host structures. They sustain low-energy Einstein-like modes in their phonon spectra, but are also prone to various types of disorder and phonon-electron scattering and thus the mechanism responsible for their ultralow thermal conductivities has remained elusive. Our thermodynamic and transport measurements on various clathrate single crystal series and their comparison with ab initio simulations reveal an all phononic Kondo effect as origin. This insight devises design strategies to further suppress the thermal conductivity of clathrates and other related materials classes, with relevance for thermoelectric waste heat recovery and, more generally, phononic applications. It may also trigger theoretical work on strong correlation effects in phonon systems. Thermoelectric clathrates host guest atoms that can rattle inside their surrounding cages, yielding unusual phononic properties. Ikeda et al. show that ab initio calculations fail to account for thermodynamic and thermal transport data and propose a Kondo-like mechanism to explain the discrepancy.
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Perez CJ, Bates VJ, Kauzlarich SM. Hydride Synthesis and Thermoelectric Properties of Type-I Clathrate K8E8Ge38 (E = Al, Ga, In). Inorg Chem 2018; 58:1442-1450. [DOI: 10.1021/acs.inorgchem.8b02977] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christopher J. Perez
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Victor J. Bates
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Susan M. Kauzlarich
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
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Uchiyama H, Oshima Y, Patterson R, Iwamoto S, Shiomi J, Shimamura K. Phonon Lifetime Observation in Epitaxial ScN Film with Inelastic X-Ray Scattering Spectroscopy. PHYSICAL REVIEW LETTERS 2018; 120:235901. [PMID: 29932681 DOI: 10.1103/physrevlett.120.235901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/21/2018] [Indexed: 06/08/2023]
Abstract
Phonon-phonon scattering dominates the thermal properties in nonmetallic materials, and it directly influences device performance in applications. The understanding of the scattering has been progressing using computational approaches, and the direct and systematic observation of phonon modes that include momentum dependences is desirable. We report experimental data on the phonon dispersion curves and lifetimes in an epitaxially grown ScN film using inelastic x-ray scattering measurements. The momentum dependence of the optical phonon lifetimes is estimated from the spectral width, and the highest-energy phonon mode around the zone center is found to possess a short lifetime of 0.21 ps. A comparison with first-principles calculations shows that our observed phonon lifetimes are quantitatively explained by three-body phonon-phonon interactions.
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Affiliation(s)
- H Uchiyama
- Research and Utilization Division, Japan Synchrotron Radiation Research Institute (JASRI), SPring-8, 1-1-1 Koto, Sayo, Hyogo 679-5198, Japan
| | - Y Oshima
- Optical Single Crystals Group, Environment and Energy Materials Research Division, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - R Patterson
- School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney 2052, Australia
| | - S Iwamoto
- Department of Mechanical Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan
| | - J Shiomi
- Department of Mechanical Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan
| | - K Shimamura
- Optical Single Crystals Group, Environment and Energy Materials Research Division, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
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Sassi S, Candolfi C, Dauscher A, Lenoir B, Koza MM. Inelastic neutron scattering study of the lattice dynamics of the homologous compounds (PbSe) 5(Bi 2Se 3) 3m (m = 1, 2 and 3). Phys Chem Chem Phys 2018; 20:14597-14607. [PMID: 29766168 DOI: 10.1039/c8cp01277f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report on the inelastic response of the homologous compounds (PbSe)5(Bi2Se3)3m for m = 1, 2 and 3 followed in a broad temperature range (50-500 K) using high-resolution powder inelastic neutron scattering experiments. These results are complemented by low-temperature measurements of the specific heat (2-300 K). The evolution of the anisotropic crystal structure of these compounds with varying m, built from alternate Pb-Se and mBi-Se layers, only weakly influences the generalized phonon density of states. In all the three compounds, intense inelastic signals, likely mainly associated with the dynamics of the Pb atoms, are observed in the 4.5-6 meV low-energy range. The response of these low-energy modes to temperature variations indicates a conventional quasi-harmonic behavior over the whole temperature range investigated. The modes located above 8 meV show a minor temperature effect regardless of the value of m. The low-energy excess of vibrational modes manifests itself in the low-temperature specific heat as a pronounced peak in the Cp(T)/T3 data near 10 K. The lack of significant anharmonicity beyond that associated with the thermal expansion of the lattice suggests that the inherent disorder in the monoclinic unit cell and scattering at interlayer interfaces are the most important ingredients that limit the heat transport in this series of compounds.
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Affiliation(s)
- Selma Sassi
- Institut Jean Lamour, UMR 7198 CNRS, Université de Lorraine, 2 allée André Guinier-Campus ARTEM, BP 50840, 54011 Nancy Cedex, France.
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Tadano T, Tsuneyuki S. Quartic Anharmonicity of Rattlers and Its Effect on Lattice Thermal Conductivity of Clathrates from First Principles. PHYSICAL REVIEW LETTERS 2018; 120:105901. [PMID: 29570340 DOI: 10.1103/physrevlett.120.105901] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/10/2017] [Indexed: 06/08/2023]
Abstract
We investigate the role of the quartic anharmonicity in the lattice dynamics and thermal transport of the type-I clathrate Ba_{8}Ga_{16}Ge_{30} based on ab initio self-consistent phonon calculations. We show that the strong quartic anharmonicity of rattling guest atoms causes the hardening of vibrational frequencies of low-lying optical modes and thereby affects calculated lattice thermal conductivities κ_{L} significantly, resulting in an improved agreement with experimental results including the deviation from κ_{L}∝T^{-1} at high temperature. Moreover, our static simulations with various different cell volumes shows a transition from crystal-like to glasslike κ_{L} around 20 K. Our analyses suggest that the resonance dip of κ_{L} observed in clathrates with large guest free spaces is attributed mainly to the strong three-phonon scattering of acoustic modes along with the presence of higher-frequency dispersive optical modes.
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Affiliation(s)
- Terumasa Tadano
- International Center for Young Scientists (ICYS), National Institute for Materials Science, Tsukuba 305-0047, Japan
- Research and Services Division of Materials Data and Integrated System (MaDIS), National Institute for Materials Science, Tsukuba 305-0047, Japan
| | - Shinji Tsuneyuki
- Department of Physics, The University of Tokyo, Tokyo 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, Kashiwa 277-8581, Japan
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