1
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Haque SRU, Michael MH, Zhu J, Zhang Y, Windgätter L, Latini S, Wakefield JP, Zhang GF, Zhang J, Rubio A, Checkelsky JG, Demler E, Averitt RD. Terahertz parametric amplification as a reporter of exciton condensate dynamics. NATURE MATERIALS 2024; 23:796-802. [PMID: 38172546 DOI: 10.1038/s41563-023-01755-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 11/06/2023] [Indexed: 01/05/2024]
Abstract
Condensates are a hallmark of emergence in quantum materials such as superconductors and charge density waves. Excitonic insulators are an intriguing addition to this library, exhibiting spontaneous condensation of electron-hole pairs. However, condensate observables can be obscured through parasitic coupling to the lattice. Here we employ nonlinear terahertz spectroscopy to disentangle such obscurants through measurement of the quantum dynamics. We target Ta2NiSe5, a putative room-temperature excitonic insulator in which electron-lattice coupling dominates the structural transition (Tc = 326 K), hindering identification of excitonic correlations. A pronounced increase in the terahertz reflectivity manifests following photoexcitation and exhibits a Bose-Einstein condensation-like temperature dependence well below the Tc, suggesting an approach to monitor the exciton condensate dynamics. Nonetheless, dynamic condensate-phonon coupling remains as evidenced by peaks in the enhanced reflectivity spectrum at select infrared-active phonon frequencies, indicating that parametric reflectivity enhancement arises from phonon squeezing. Our results highlight that coherent dynamics can drive parametric stimulated emission.
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Affiliation(s)
- Sheikh Rubaiat Ul Haque
- Department of Physics, University of California San Diego, La Jolla, CA, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | | | - Junbo Zhu
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yuan Zhang
- Department of Physics, University of California San Diego, La Jolla, CA, USA
| | - Lukas Windgätter
- Max Planck Institute for the Structure and Dynamics of Matter (MPSD), Hamburg, Germany
| | - Simone Latini
- Max Planck Institute for the Structure and Dynamics of Matter (MPSD), Hamburg, Germany
| | - Joshua P Wakefield
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Gu-Feng Zhang
- Department of Physics, University of California San Diego, La Jolla, CA, USA
| | - Jingdi Zhang
- Department of Physics, University of California San Diego, La Jolla, CA, USA
- Department of Physics, The Hong Kong University of Science and Technology, Hongkong, China
| | - Angel Rubio
- Max Planck Institute for the Structure and Dynamics of Matter (MPSD), Hamburg, Germany
- Center for Computational Quantum Physics, The Flatiron Institute, New York, NY, USA
| | - Joseph G Checkelsky
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Eugene Demler
- Department of Physics, Harvard University, Cambridge, MA, USA
- Institute for Theoretical Physics, ETH Zürich, Zürich, Switzerland
| | - Richard D Averitt
- Department of Physics, University of California San Diego, La Jolla, CA, USA.
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2
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Caicedo-Dávila S, Cohen A, Motti SG, Isobe M, McCall KM, Grumet M, Kovalenko MV, Yaffe O, Herz LM, Fabini DH, Egger DA. Disentangling the effects of structure and lone-pair electrons in the lattice dynamics of halide perovskites. Nat Commun 2024; 15:4184. [PMID: 38760360 PMCID: PMC11101661 DOI: 10.1038/s41467-024-48581-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 05/06/2024] [Indexed: 05/19/2024] Open
Abstract
Halide perovskites show great optoelectronic performance, but their favorable properties are paired with unusually strong anharmonicity. It was proposed that this combination derives from the ns2 electron configuration of octahedral cations and associated pseudo-Jahn-Teller effect. We show that such cations are not a prerequisite for the strong anharmonicity and low-energy lattice dynamics encountered in these materials. We combine X-ray diffraction, infrared and Raman spectroscopies, and molecular dynamics to contrast the lattice dynamics of CsSrBr3 with those of CsPbBr3, two compounds that are structurally similar but with the former lacking ns2 cations with the propensity to form electron lone pairs. We exploit low-frequency diffusive Raman scattering, nominally symmetry-forbidden in the cubic phase, as a fingerprint of anharmonicity and reveal that low-frequency tilting occurs irrespective of octahedral cation electron configuration. This highlights the role of structure in perovskite lattice dynamics, providing design rules for the emerging class of soft perovskite semiconductors.
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Affiliation(s)
- Sebastián Caicedo-Dávila
- Physics Department, TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
| | - Adi Cohen
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Silvia G Motti
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
- School of Physics and Astronomy, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Masahiko Isobe
- Max Planck Institute for Solid State Research, Stuttgart, Germany
| | - Kyle M McCall
- Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zürich, Switzerland
- Laboratory for Thin Films and Photovoltaics, EMPA - Swiss National Laboratories for Materials and Technology, Dübendorf, Switzerland
- Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, TX, USA
| | - Manuel Grumet
- Physics Department, TUM School of Natural Sciences, Technical University of Munich, Garching, Germany
| | - Maksym V Kovalenko
- Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zürich, Switzerland
- Laboratory for Thin Films and Photovoltaics, EMPA - Swiss National Laboratories for Materials and Technology, Dübendorf, Switzerland
| | - Omer Yaffe
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Laura M Herz
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
- TUM Institute for Advanced Study, Technical University of Munich, Garching, Germany
| | - Douglas H Fabini
- Max Planck Institute for Solid State Research, Stuttgart, Germany.
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - David A Egger
- Physics Department, TUM School of Natural Sciences, Technical University of Munich, Garching, Germany.
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3
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Ma Y, Li C, Guo L, Lu W, Cheng Y, Han X, Li J, Crawshaw D, He M, Shan L, Lee D, da Silva I, Manuel P, Ramirez-Cuesta AJ, Schröder M, Yang S. Exceptional capture of methane at low pressure by an iron-based metal-organic framework. Chemistry 2024; 30:e202303934. [PMID: 38102961 DOI: 10.1002/chem.202303934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 12/17/2023]
Abstract
The selective capture of methane (CH4) at low concentrations and its separation from N2 are extremely challenging owing to the weak host-guest interactions between CH4 molecules and any sorbent material. Here, we report the exceptional adsorption of CH4 at low pressure and the efficient separation of CH4/N2 by MFM-300(Fe). MFM-300(Fe) shows a very high uptake for CH4 of 0.85 mmol g-1 at 1 mbar and 298 K and a record CH4/N2 selectivity of 45 for porous solids, representing a new benchmark for CH4 capture and CH4/N2 separation. The excellent separation of CH4/N2 by MFM-300(Fe) has been confirmed by dynamic breakthrough experiments. In situ neutron powder diffraction, and solid-state nuclear magnetic resonance and diffuse reflectance infrared Fourier transform spectroscopies, coupled with modelling, reveal a unique and strong binding of CH4 molecules involving Fe-OH⋯CH4 and C⋯phenyl ring interactions within the pores of MFM-300(Fe), thus promoting the exceptional adsorption of CH4 at low pressure.
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Affiliation(s)
- Yujie Ma
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Cheng Li
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Lixia Guo
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Wanpeng Lu
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Yongqiang Cheng
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Xue Han
- College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Jiangnan Li
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Danielle Crawshaw
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Meng He
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Lutong Shan
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Daniel Lee
- Department of Chemical Engineering, University of Manchester, Manchester, M13 9PL, UK
| | - Ivan da Silva
- ISIS Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, OX11 0QX, UK
| | - Pascal Manuel
- ISIS Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, OX11 0QX, UK
| | | | - Martin Schröder
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
| | - Sihai Yang
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
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4
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Li Y, Xu L, Ouyang J, Lei J, Hu J, Xing X, Chen P, Li J, Zhong C, Yang B, Li H. Harmonic and anharmonic studies on THz spectra of two vanillin polymorphs. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 309:123869. [PMID: 38198992 DOI: 10.1016/j.saa.2024.123869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 12/05/2023] [Accepted: 01/05/2024] [Indexed: 01/12/2024]
Abstract
Polymorphism commonly exists in organic molecular crystals. The fingerprint features in low-frequency vibrational range are important information reflecting different intermolecular interactions of polymorphs. Interpreting these features is very helpful to understand vibrational property of polymorphs and reveal the thermodynamic stability. In this work, the low-frequency vibrations of form I and II of vanillin are investigated using terahertz time-domain spectroscopy. Static DFT calculation and ab initio molecular dynamics (AIMD) are employed to interpret their low-frequency vibrations of both forms in harmonic and anharmonic ways, respectively. Their low-frequency vibration characteristics in harmonic calculations are discussed, and anharmonic mode couplings between OH bond stretch and the stretching and bending motion of hydrogen bonds are uncovered. Moreover, the thermodynamic energies including electronic potential energy and vibrational/kinetic energy arising from nuclear motions are calculated. The result reveals that the stability order of the two forms is mainly dependent on their electric potential energy difference.
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Affiliation(s)
- Yin Li
- School of Physics and Materials Science, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China.
| | - Li Xu
- School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Jinbo Ouyang
- School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China.
| | - Jiangtao Lei
- Institute of Space Science and Technology, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Jun Hu
- School of Mechatronics & Vehicle Engineering, East China Jiaotong University, Nanchang, Jiangxi 330013, China
| | - Xiaohong Xing
- School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Peng Chen
- School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Jiaqing Li
- School of Physics and Materials Science, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Changqing Zhong
- School of Physics and Materials Science, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Bo Yang
- School of Physics and Materials Science, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Heng Li
- Fujian Provincial Key Laboratory of Semiconductors and Applications, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Department of Physics, Xiamen University, Xiamen 361005, China; Jiujiang Research Institute, Xiamen University, Jiujiang 332000, China
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5
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Paschoal VH, Ribeiro MCC. Phase transitions of choline dihydrogen phosphate: A vibrational spectroscopy and periodic DFT study. J Chem Phys 2024; 160:094507. [PMID: 38445739 DOI: 10.1063/5.0189049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Accepted: 02/19/2024] [Indexed: 03/07/2024] Open
Abstract
Choline dihydrogen phosphate, [Chol][H2PO4], is a proton-conducting ionic plastic crystal exhibiting a complicated sequence of phase transitions. Here, we address the argument in the literature around the thermal properties of [Chol][H2PO4] using Raman and infrared microspectroscopy. The known structure of the low-temperature crystal, which contains the anti-conformer of [Chol]+ and hydrogen-bonded dimers of anions, was used to do periodic density functional theory calculations of the vibrational frequencies. Raman spectra indicate that the solid-solid transition at 20 °C is linked to a conformational change to the gauche [Chol] conformer with a concurrent local rearrangement of the anions. The distinct bands of lattice modes in the low-frequency range of the Raman spectra vanish at the 20 °C transition. Given the ease with which metastable crystals can be produced, Raman mappings demonstrate that a sample of [Chol][H2PO4] at ambient temperature can contain a combination of anti- and gauche conformers. Heating to 120 °C causes continuous changes in the local environment of anions rather than melting as suggested by a recent calorimetric investigation of [Chol][H2PO4]. The monotonic change in vibrational spectra is consistent with earlier observations of a very small entropy of fusion and no abrupt jump in the temperature dependence of ionic conductivity along the phase transitions of [Chol][H2PO4].
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Affiliation(s)
- Vitor H Paschoal
- Laboratório de Espectroscopia Molecular, Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, 05513-970 São Paulo, Brazil
| | - Mauro C C Ribeiro
- Laboratório de Espectroscopia Molecular, Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, 05513-970 São Paulo, Brazil
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6
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Patyk-Kaźmierczak E, Izquierdo-Ruiz F, Lobato A, Kaźmierczak M, Moszczyńska I, Olejniczak A, Recio JM. The curious case of proton migration under pressure in the malonic acid and 4,4'-bipyridine cocrystal. IUCRJ 2024; 11:168-181. [PMID: 38275161 PMCID: PMC10916288 DOI: 10.1107/s2052252524000344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 01/09/2024] [Indexed: 01/27/2024]
Abstract
In the search for new active pharmaceutical ingredients, the precise control of the chemistry of cocrystals becomes essential. One crucial step within this chemistry is proton migration between cocrystal coformers to form a salt, usually anticipated by the empirical ΔpKa rule. Due to the effective role it plays in modifying intermolecular distances and interactions, pressure adds a new dimension to the ΔpKa rule. Still, this variable has been scarcely applied to induce proton-transfer reactions within these systems. In our study, high-pressure X-ray diffraction and Raman spectroscopy experiments, supported by DFT calculations, reveal modifications to the protonation states of the 4,4'-bipyridine (BIPY) and malonic acid (MA) cocrystal (BIPYMA) that allow the conversion of the cocrystal phase into ionic salt polymorphs. On compression, neutral BIPYMA and monoprotonated (BIPYH+MA-) species coexist up to 3.1 GPa, where a phase transition to a structure of P21/c symmetry occurs, induced by a double proton-transfer reaction forming BIPYH22+MA2-. The low-pressure C2/c phase is recovered at 2.4 GPa on decompression, leading to a 0.7 GPa hysteresis pressure range. This is one of a few studies on proton transfer in multicomponent crystals that shows how susceptible the interconversion between differently charged species is to even slight pressure changes, and how the proton transfer can be a triggering factor leading to changes in the crystal symmetry. These new data, coupled with information from previous reports on proton-transfer reactions between coformers, extend the applicability of the ΔpKa rule incorporating the pressure required to induce salt formation.
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Affiliation(s)
- Ewa Patyk-Kaźmierczak
- Facuty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, Poznań 61-614, Poland
| | - Fernando Izquierdo-Ruiz
- MALTA-Consolider Team and Departamento de Química Física, University Complutense of Madrid, Avda. de Séneca, 2 Ciudad Universitaria, Madrid 28040, Spain
| | - Alvaro Lobato
- MALTA-Consolider Team and Departamento de Química Física, University Complutense of Madrid, Avda. de Séneca, 2 Ciudad Universitaria, Madrid 28040, Spain
| | - Michał Kaźmierczak
- Facuty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, Poznań 61-614, Poland
| | - Ida Moszczyńska
- Facuty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, Poznań 61-614, Poland
| | - Anna Olejniczak
- Facuty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, Poznań 61-614, Poland
| | - J. Manuel Recio
- MALTA-Consolider Team and Departamento de Química Física y Analítica, University of Oviedo, Julián Clavería n° 8, Oviedo 33006, Spain
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7
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Musfeldt JL, Singh S, Fan S, Gu Y, Xu X, Cheong SW, Liu Z, Vanderbilt D, Rabe KM. Structural phase purification of bulk HfO 2:Y through pressure cycling. Proc Natl Acad Sci U S A 2024; 121:e2312571121. [PMID: 38266049 PMCID: PMC10835063 DOI: 10.1073/pnas.2312571121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 12/05/2023] [Indexed: 01/26/2024] Open
Abstract
We combine synchrotron-based infrared absorption and Raman scattering spectroscopies with diamond anvil cell techniques and first-principles calculations to explore the properties of hafnia under compression. We find that pressure drives HfO[Formula: see text]:7%Y from the mixed monoclinic ([Formula: see text]) [Formula: see text] antipolar orthorhombic ([Formula: see text]) phase to pure antipolar orthorhombic ([Formula: see text]) phase at approximately 6.3 GPa. This transformation is irreversible, meaning that upon release, the material is kinetically trapped in the [Formula: see text] metastable state at 300 K. Compression also drives polar orthorhombic ([Formula: see text]) hafnia into the tetragonal ([Formula: see text]) phase, although the latter is not metastable upon release. These results are unified by an analysis of the energy landscape. The fact that pressure allows us to stabilize targeted metastable structures with less Y stabilizer is important to preserving the flat phonon band physics of pure HfO[Formula: see text].
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Affiliation(s)
- J L Musfeldt
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996
| | - Sobhit Singh
- Department of Mechanical Engineering, University of Rochester, Rochester, NY 14627
- Materials Science Program, University of Rochester, Rochester, NY 14627
| | - Shiyu Fan
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973
| | - Yanhong Gu
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996
| | - Xianghan Xu
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ 08854
| | - S-W Cheong
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ 08854
| | - Z Liu
- Department of Physics, University of Illinois, Chicago, IL 60607-7059
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - Karin M Rabe
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
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8
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Cheng B, Cheng D, Jiang T, Xia W, Song B, Mootz M, Luo L, Perakis IE, Yao Y, Guo Y, Wang J. Chirality manipulation of ultrafast phase switches in a correlated CDW-Weyl semimetal. Nat Commun 2024; 15:785. [PMID: 38278821 PMCID: PMC10817907 DOI: 10.1038/s41467-024-45036-1] [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: 09/07/2023] [Accepted: 01/11/2024] [Indexed: 01/28/2024] Open
Abstract
Light engineering of correlated states in topological materials provides a new avenue of achieving exotic topological phases inaccessible by conventional tuning methods. Here we demonstrate a light control of correlation gaps in a model charge-density-wave (CDW) and polaron insulator (TaSe4)2I recently predicted to be an axion insulator. Our ultrafast terahertz photocurrent spectroscopy reveals a two-step, non-thermal melting of polarons and electronic CDW gap via the fluence dependence of a longitudinal circular photogalvanic current. This helicity-dependent photocurrent reveals continuous ultrafast phase switches from the polaronic state to the CDW (axion) phase, and finally to a hidden Weyl phase as the pump fluence increases. Additional distinctive attributes aligning with the light-induced switches include: the mode-selective coupling of coherent phonons to the polaron and CDW modulation, and the emergence of a non-thermal chiral photocurrent above the pump threshold of CDW-related phonons. The demonstrated ultrafast chirality control of correlated topological states here holds large potentials for realizing axion electrodynamics and advancing quantum-computing applications.
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Affiliation(s)
- Bing Cheng
- Ames National Laboratory, Ames, IA, 50011, USA.
| | - Di Cheng
- Ames National Laboratory, Ames, IA, 50011, USA
| | - Tao Jiang
- Ames National Laboratory, Ames, IA, 50011, USA
| | - Wei Xia
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 201210, China
| | - Boqun Song
- Ames National Laboratory, Ames, IA, 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
| | - Martin Mootz
- Ames National Laboratory, Ames, IA, 50011, USA
- Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
| | - Liang Luo
- Ames National Laboratory, Ames, IA, 50011, USA
| | - Ilias E Perakis
- Department of Physics, University of Alabama at Birmingham, Birmingham, AL, 35294-1170, USA
| | - Yongxin Yao
- Ames National Laboratory, Ames, IA, 50011, USA
| | - Yanfeng Guo
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
- ShanghaiTech Laboratory for Topological Physics, Shanghai, 201210, China
| | - Jigang Wang
- Ames National Laboratory, Ames, IA, 50011, USA.
- Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA.
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9
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Roy AP, Ss J, Dwij V, Khandelwal A, Chattopadhyay MK, Sathe V, Mittal R, Sastry PU, Achary SN, Tyagi AK, Babu PD, Le MD, Bansal D. Evidence of Strong Orbital-Selective Spin-Orbital-Phonon Coupling in CrVO_{4}. PHYSICAL REVIEW LETTERS 2024; 132:026701. [PMID: 38277598 DOI: 10.1103/physrevlett.132.026701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 12/05/2023] [Accepted: 12/14/2023] [Indexed: 01/28/2024]
Abstract
Coupling of orbital degree of freedom with a spin exchange, i.e., Kugel-Khomskii-type interaction (KK), governs a host of material properties, including colossal magnetoresistance, enhanced magnetoelectric response, and photoinduced high-temperature magnetism. In general, KK-type interactions lead to deviation in experimental observables of coupled Hamiltonian near or below the magnetic transition. Using diffraction and spectroscopy experiments, here we report anomalous changes in lattice parameters, electronic states, spin dynamics, and phonons at four times the Néel transition temperature (T_{N}) in CrVO_{4}. The temperature is significantly higher than other d-orbital compounds such as manganites and vanadates, where effects are limited to near or below T_{N}. The experimental observations are rationalized using first-principles and Green's function-based phonon and spin simulations that show unprecedentedly strong KK-type interactions via a superexchange process and an orbital-selective spin-phonon coupling coefficient at least double the magnitude previously reported for strongly coupled spin-phonon systems. Our results present an opportunity to explore the effect of KK-type interactions and spin-phonon coupling well above T_{N} and possibly bring various properties closer to application, for example, strong room-temperature magnetoelectric coupling.
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Affiliation(s)
- Aditya Prasad Roy
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra 400076, India
| | - Jayakrishnan Ss
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra 400076, India
| | - Vivek Dwij
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai, Maharashtra 400076, India
| | - Ashish Khandelwal
- Free Electron Laser Utilization Laboratory, Raja Ramanna Centre for Advanced Technology, Indore, Madhya Pradesh 452013, India
| | - M K Chattopadhyay
- Free Electron Laser Utilization Laboratory, Raja Ramanna Centre for Advanced Technology, Indore, Madhya Pradesh 452013, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | - Vasant Sathe
- UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore, Madhya Pradesh 452001, India
| | - Ranjan Mittal
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India
| | - P U Sastry
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India
| | - Srungarpu N Achary
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
- Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - Avesh K Tyagi
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India
- Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - Peram D Babu
- UGC-DAE Consortium for Scientific Research, Mumbai Centre, R5-Shed, BARC, Trombay, Mumbai, Maharashtra 400085, India
| | - Manh Duc Le
- ISIS facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX Oxfordshire, United Kingdom
| | - Dipanshu Bansal
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra 400076, India
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10
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Marqueño T, Kuzovnikov MA, Osmond I, Dalladay-Simpson P, Hermann A, Howie RT, Peña-Alvarez M. High pressure study of sodium trihydride. Front Chem 2024; 11:1306495. [PMID: 38264124 PMCID: PMC10803492 DOI: 10.3389/fchem.2023.1306495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 12/19/2023] [Indexed: 01/25/2024] Open
Abstract
The reactivity between NaH and H2 has been investigated through a series of high-temperature experiments up to pressures of 78 GPa in diamond anvil cells combined with first principles calculations. Powder X-ray diffraction measurements show that heating NaH in an excess of H2 to temperatures around 2000 K above 27 GPa yields sodium trihydride (NaH3), which adopts an orthorhombic structure (space group Cmcm). Raman spectroscopy measurements indicate that NaH3 hosts quasi-molecular hydrogen (H 2 δ - ) within a NaH lattice, with the H 2 δ - stretching mode downshifted compared to pure H2 (Δν ∼-120 cm-1 at 50 GPa). NaH3 is stable under room temperature compression to at least 78 GPa, and exhibits remarkable P-T stability, decomposing at pressures below 18 GPa. Contrary to previous experimental and theoretical studies, heating NaH (or NaH3) in excess H2 between 27 and 75 GPa does not promote further hydrogenation to form sodium polyhydrides other than NaH3.
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Affiliation(s)
- Tomas Marqueño
- Centre for Science at Extreme Conditions (CSEC), The School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
| | - Mikhail A. Kuzovnikov
- Centre for Science at Extreme Conditions (CSEC), The School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
| | - Israel Osmond
- Centre for Science at Extreme Conditions (CSEC), The School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
| | | | - Andreas Hermann
- Centre for Science at Extreme Conditions (CSEC), The School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
| | - Ross T. Howie
- Centre for Science at Extreme Conditions (CSEC), The School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
- Center for High Pressure Science and Technology Advanced Research, Shanghai, China
| | - Miriam Peña-Alvarez
- Centre for Science at Extreme Conditions (CSEC), The School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
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11
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Luo Y, Li C, Zhong C, Li S. A novel 2D intrinsic metal-free ferromagnetic semiconductor Si 3C 8 monolayer. Phys Chem Chem Phys 2024; 26:1086-1093. [PMID: 38098345 DOI: 10.1039/d3cp05005j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Metal-free magnets, a special kind of ferromagnetic (FM) material, have evolved into an important branch of magnetic materials for spintronic applications. We herein propose a silicon carbide (Si3C8) monolayer and investigate its geometric, electronic, and magnetic properties by using first-principles calculations. The thermal and dynamical stability of the Si3C8 monolayer was confirmed by ab initio molecular dynamics and phonon dispersion simulations. Our results show that the Si3C8 monolayer is a FM semiconductor with a band gap of 1.76 eV in the spin-down channel and a Curie temperature of 22 K. We demonstrate that the intrinsic magnetism of the Si3C8 monolayer is derived from pz orbitals of C atoms via superexchange interactions. Furthermore, the half-metallic state in the FM Si3C8 monolayer can be induced by electron doping. Our work not only illustrates that carrier doping could manipulate the magnetic states of the FM Si3C8 monolayer but also provides an idea to design two-dimensional metal-free magnetic materials for spintronic applications.
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Affiliation(s)
- Yangtong Luo
- School of Mechanical Engineering, Chengdu University, Chengdu 610106, P. R. China
- Institute for Advanced Study, Chengdu University, Chengdu 610106, P. R. China.
| | - Chen Li
- School of Mechanical Engineering, Chengdu University, Chengdu 610106, P. R. China
- Institute for Advanced Study, Chengdu University, Chengdu 610106, P. R. China.
| | - Chengyong Zhong
- College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 400047, P. R. China.
| | - Shuo Li
- Institute for Advanced Study, Chengdu University, Chengdu 610106, P. R. China.
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12
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Ta KM, Cooke DJ, Gillie LJ, Parker SC, Seal S, Wilson PB, Phillips RM, Skelton JM, Molinari M. Infrared and Raman Diagnostic Modeling of Phosphate Adsorption on Ceria Nanoparticles. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:20183-20193. [PMID: 37850082 PMCID: PMC10577678 DOI: 10.1021/acs.jpcc.3c05409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/08/2023] [Indexed: 10/19/2023]
Abstract
Cerium dioxide (CeO2; ceria) nanoparticles (CeNPs) are promising nanozymes that show a variety of biological activity. Effective nanozymes need to retain their activity in the face of surface speciation in biological environments, and characterizing surface speciation is therefore critical to understanding and controlling the therapeutic capabilities of CeNPs. In particular, adsorbed phosphates can impact the enzymatic activity exploited to convert phosphate prodrugs into therapeutics in vivo and also define the early stages of the phosphate-scavenging processes that lead to the transformation of active CeO2 into inactive CePO4. In this work, we utilize ab initio lattice-dynamics calculations to study the interaction of phosphates with the three major surfaces of ceria and to predict the infrared (IR) and Raman spectral signatures of adsorbed phosphate species. We find that phosphates adsorb strongly to CeO2 surfaces in a range of stable binding configurations, of which 5-fold coordinated P species in a trigonal bipyramidal coordination may represent a stable intermediate in the early stages of phosphate scavenging. We find that the phosphate species show characteristic spectral fingerprints between 500 and 1500 cm-1, whereas the bare CeO2 surfaces show no active modes above 600 cm-1, and the 5-fold coordinated P species in particular show potential diagnostic P-O stretching modes between 650 and 700 cm-1 in both IR and Raman spectra. This comprehensive exploration of different binding modes for phosphates on CeO2 and the set of reference spectra provides an important step toward the experimental characterization of phosphate speciation and, ultimately, control of its impact on the performance of ceria nanozymes.
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Affiliation(s)
- Khoa Minh Ta
- Department
of Chemistry, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K.
| | - David J. Cooke
- Department
of Chemistry, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K.
| | - Lisa J. Gillie
- Department
of Chemistry, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K.
| | - Stephen C. Parker
- Department
of Chemistry, University of Bath, Claverton
Down, Bath BA2 7AY, U.K.
| | - Sudipta Seal
- Department
of Materials Science & Engineering, Advanced Materials Processing
and Analysis Centre (AMPAC), Nanoscience Technology Centre (NSTC), University of Central Florida, Orlando, Florida 32816, United States
- Bionix
Cluster, College of Medicine, University
of Central Florida, Orlando, Florida 32827, United States
| | - Philippe B. Wilson
- School
of Animal, Rural and Environmental Sciences, Brackenhurst Campus, Nottingham Trent University, Southwell NG25 0QF, U.K.
| | - Roger M. Phillips
- Department
of Pharmacy, School of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH, U.K.
| | | | - Marco Molinari
- Department
of Chemistry, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K.
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13
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Magnera TF, Dron PI, Bozzone JP, Jovanovic M, Rončević I, Tortorici E, Bu W, Miller EM, Rogers CT, Michl J. Porphene and porphite as porphyrin analogs of graphene and graphite. Nat Commun 2023; 14:6308. [PMID: 37813887 PMCID: PMC10562370 DOI: 10.1038/s41467-023-41461-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 09/01/2023] [Indexed: 10/11/2023] Open
Abstract
Two-dimensional materials have unusual properties and promise applications in nanoelectronics, spintronics, photonics, (electro)catalysis, separations, and elsewhere. Most are inorganic and their properties are difficult to tune. Here we report the preparation of Zn porphene, a member of the previously only hypothetical organic metalloporphene family. Similar to graphene, these also are fully conjugated two-dimensional polymers, but are composed of fused metalloporphyrin rings. Zn porphene is synthesized on water surface by two-dimensional oxidative polymerization of a Langmuir layer of Zn porphyrin with K2IrCl6, reminiscent of known one-dimensional polymerization of pyrroles. It is transferable to other substrates and bridges μm-sized pits. Contrary to previous theoretical predictions of metallic conductivity, it is a p-type semiconductor due to a predicted Peierls distortion of its unit cell from square to rectangular, analogous to the appearance of bond-length alternation in antiaromatic molecules. The observed reversible insertion of various metal ions, possibly carrying a fifth or sixth ligand, promises tunability and even patterning of circuits on an atomic canvas without removing any π centers from conjugation.
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Grants
- University of Colorado Boulder Institute of Organic Chemistry and Biochemistry, RVO: 61388963 The Czech Science Foundation grant 20-03691X
- Army Research Laboratory and Army Research Office grant W911NF-15-1-0435 National Science Foundation grant CHE 1900226 DARPA grant HR00111810006 University of Colorado Boulder
- Army Research Laboratory and Army Research Office grant W911NF-15-1-0435 National Science Foundation grant CHE 1900226 University of Colorado Boulder
- University of Colorado Boulder Research Computing Group, funded by National Science Foundation grants ACI-1532235 and ACI-1532236, and Colorado State University Institute of Organic Chemistry and Biochemistry, RVO: 61388963 The Czech Science Foundation grant 20-03691X Czech Ministry of Education, Youth and Sports grant e-INFRA CZ, ID:90140 Wallonia-Brussels International Excellence Grant (IR)
- Department of Energy Office of Science, BES, Division of Chemical Sciences, Geosciences and Biosciences, Solar Photochemistry. The views expressed in the article do not necessarily represent the views of the Department of Energy or the U.S. Government. Alliance for Sustainable Energy, LLC, operating NREL for Department of Energy grant DE-AC36-08GO28308
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Affiliation(s)
- Thomas F Magnera
- Department of Chemistry, University of Colorado, Boulder, CO, 80309, USA
| | - Paul I Dron
- Department of Chemistry, University of Colorado, Boulder, CO, 80309, USA
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Jared P Bozzone
- Department of Chemistry, University of Colorado, Boulder, CO, 80309, USA
| | - Milena Jovanovic
- Department of Chemistry, University of Colorado, Boulder, CO, 80309, USA
| | - Igor Rončević
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Edward Tortorici
- Department of Physics, University of Colorado, Boulder, CO, 80309, USA
| | - Wei Bu
- ChemMatCARS, University of Chicago, Lemont, IL, 60439, USA
| | - Elisa M Miller
- Chemistry and Nanoscience Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Charles T Rogers
- Department of Physics, University of Colorado, Boulder, CO, 80309, USA
- Renewable and Sustainable Energy Institute (RASEI) at the University of Colorado, Boulder, CO, 80303, USA
| | - Josef Michl
- Department of Chemistry, University of Colorado, Boulder, CO, 80309, USA.
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, Czech Republic.
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14
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Wang M, Kuzovnikov MA, Binns J, Li X, Peña-Alvarez M, Hermann A, Gregoryanz E, Howie RT. Synthesis and characterization of XeAr2 under high pressure. J Chem Phys 2023; 159:134508. [PMID: 37795788 DOI: 10.1063/5.0158742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 09/13/2023] [Indexed: 10/06/2023] Open
Abstract
The binary Xe-Ar system has been studied in a series of high pressure diamond anvil cell experiments up to 60 GPa at 300 K. In-situ x-ray powder diffraction and Raman spectroscopy indicate the formation of a van der Waals compound, XeAr2, at above 3.5 GPa. Powder x-ray diffraction analysis demonstrates that XeAr2 adopts a Laves MgZn2-type structure with space group P63/mmc and cell parameters a = 6.595 Å and c = 10.716 Å at 4 GPa. Density functional theory calculations support the structure determination, with agreement between experimental and calculated Raman spectra. Our DFT calculations suggest that XeAr2 would remain stable without a structural transformation or decomposition into elemental Xe and Ar up to at least 80 GPa.
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Affiliation(s)
- Mengnan Wang
- Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Mikhail A Kuzovnikov
- Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Jack Binns
- Center for High Pressure Science and Technology Advanced Research, Shanghai, China
| | - Xiaofeng Li
- College of Physics and Electronic Information, Luoyang Normal University, Luoyang, China
| | - Miriam Peña-Alvarez
- Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Andreas Hermann
- Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Eugene Gregoryanz
- Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
- Center for High Pressure Science and Technology Advanced Research, Shanghai, China
- Key Laboratory of Materials Physics, Institute of Solid State Physics, CAS, Hefei, China
| | - Ross T Howie
- Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
- Center for High Pressure Science and Technology Advanced Research, Shanghai, China
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15
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Hao Y, Wang L, Huang LF. Lanthanide-doped MoS 2 with enhanced oxygen reduction activity and biperiodic chemical trends. Nat Commun 2023; 14:3256. [PMID: 37277362 DOI: 10.1038/s41467-023-39100-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 05/30/2023] [Indexed: 06/07/2023] Open
Abstract
Molybdenum disulfide has broad applications in catalysis, optoelectronics, and solid lubrication, where lanthanide (Ln) doping can be used to tune its physicochemical properties. The reduction of oxygen is an electrochemical process important in determining fuel cell efficiency, or a possible environmental-degradation mechanism for nanodevices and coatings consisting of Ln-doped MoS2. Here, by combining density-functional theory calculations and current-potential polarization curve simulations, we show that the dopant-induced high oxygen reduction activity at Ln-MoS2/water interfaces scales as a biperiodic function of Ln type. A defect-state pairing mechanism, which selectively stabilizes the hydroxyl and hydroperoxyl adsorbates on Ln-MoS2, is proposed for the activity enhancement, and the biperiodic chemical trend in activity is found originating from the similar trends in intraatomic 4f-5d6s orbital hybridization and interatomic Ln-S bonding. A generic orbital-chemistry mechanism is described for explaining the simultaneous biperiodic trends observed in many electronic, thermodynamic, and kinetic properties.
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Affiliation(s)
- Yu Hao
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 315201, Ningbo, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Liping Wang
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 315201, Ningbo, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, 100049, Beijing, China.
| | - Liang-Feng Huang
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 315201, Ningbo, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, 100049, Beijing, China.
- Research Center for Advanced Interdisciplinary Sciences, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 315201, Ningbo, China.
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16
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Lin DY, Hsu HP, Liu KH, Wu PH, Shih YT, Wu YF, Wang YP, Lin CF. Enhanced Optical Response of SnS/SnS 2 Layered Heterostructure. SENSORS (BASEL, SWITZERLAND) 2023; 23:4976. [PMID: 37430888 DOI: 10.3390/s23104976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 07/12/2023]
Abstract
The SnS/SnS2 heterostructure was fabricated by the chemical vapor deposition method. The crystal structure properties of SnS2 and SnS were characterized by X-ray diffraction (XRD) pattern, Raman spectroscopy, and field emission scanning electron microscopy (FESEM). The frequency dependence photoconductivity explores its carrier kinetic decay process. The SnS/SnS2 heterostructure shows that the ratio of short time constant decay process reaches 0.729 with a time constant of 4.3 × 10-4 s. The power-dependent photoresponsivity investigates the mechanism of electron-hole pair recombination. The results indicate that the photoresponsivity of the SnS/SnS2 heterostructure has been increased to 7.31 × 10-3 A/W, representing a significant enhancement of approximately 7 times that of the individual films. The results show the optical response speed has been improved by using the SnS/SnS2 heterostructure. These results indicate an application potential of the layered SnS/SnS2 heterostructure for photodetection. This research provides valuable insights into the preparation of the heterostructure composed of SnS and SnS2, and presents an approach for designing high-performance photodetection devices.
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Affiliation(s)
- Der-Yuh Lin
- Department of Electronic Engineering, National Changhua University of Education, No. 2, Shi-Da Rd., Changhua 500, Taiwan
| | - Hung-Pin Hsu
- Department of Electronic Engineering, Ming Chi University of Technology, No. 84, Gongzhuan Rd., Taishan Dist., New Taipei City 243, Taiwan
| | - Kuang-Hsin Liu
- Department of Electronic Engineering, National Changhua University of Education, No. 2, Shi-Da Rd., Changhua 500, Taiwan
| | - Po-Hung Wu
- Department of Electrical Engineering, National Dong Hwa University, No. 1, Sec. 2, Da Hsueh Rd., Shoufeng, Hualien 974, Taiwan
| | - Yu-Tai Shih
- Department of Physics, National Changhua University of Education, No. 1, Jin-De Rd., Changhua 500, Taiwan
| | - Ya-Fen Wu
- Department of Electronic Engineering, Ming Chi University of Technology, No. 84, Gongzhuan Rd., Taishan Dist., New Taipei City 243, Taiwan
| | - Yi-Ping Wang
- Department of Electronic Engineering, Ming Chi University of Technology, No. 84, Gongzhuan Rd., Taishan Dist., New Taipei City 243, Taiwan
| | - Chia-Feng Lin
- Department of Materials Science and Engineering, National Chung Hsing University, No. 145, Xingda Rd., South Dist., Taichung 402, Taiwan
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17
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Heterogeneous intercalated metal-organic framework active materials for fast-charging non-aqueous Li-ion capacitors. Nat Commun 2023; 14:1472. [PMID: 36928582 PMCID: PMC10020440 DOI: 10.1038/s41467-023-37120-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 03/01/2023] [Indexed: 03/18/2023] Open
Abstract
Intercalated metal-organic frameworks (iMOFs) based on aromatic dicarboxylate are appealing negative electrode active materials for Li-based electrochemical energy storage devices. They store Li ions at approximately 0.8 V vs. Li/Li+ and, thus, avoid Li metal plating during cell operation. However, their fast-charging capability is limited. Here, to circumvent this issue, we propose iMOFs with multi-aromatic units selected using machine learning and synthesized via solution spray drying. A naphthalene-based multivariate material with nanometric thickness allows the reversible storage of Li-ions in non-aqueous Li metal cell configuration reaching 85% capacity retention at 400 mA g-1 (i.e., 30 min for full charge) and 20 °C compared to cycling at 20 mA g-1 (i.e., 10 h for full charge). The same material, tested in combination with an activated carbon-based positive electrode, enables a discharge capacity retention of about 91% after 1000 cycles at 0.15 mA cm-2 (i.e., 2 h for full charge) and 20 °C. We elucidate the charge storage mechanism and demonstrate that during Li intercalation, the distorted crystal structure promotes electron delocalization by controlling the frame vibration. As a result, a phase transition suppresses phase separation, thus, benefitting the electrode's fast charging behavior.
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18
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Yang B, Li Y, Lei J, Cai M, Hu Z, Shen Y, Deng X. Dehydration kinetics and mechanism of the stable isonicotinamide hydrate revealed by terahertz spectroscopy and DFT calculation. Int J Pharm 2023; 638:122893. [PMID: 36990167 DOI: 10.1016/j.ijpharm.2023.122893] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 03/13/2023] [Accepted: 03/23/2023] [Indexed: 03/30/2023]
Abstract
The dehydration behavior of pharmaceutical hydrates has a great influence on its physiochemical properties such as stability, dissolution rate and bioavailability. However, how the intermolecular interactions vary during dehydration process remains elusive. In this work, we employed terahertz time-domain spectroscopy (THz-TDS) to probe the low-frequency vibrations and the dehydration process of isonicotinamide hydrate I (INA-H I). Theoretical solid-state DFT calculation was conducted to reveal its mechanism. Vibrational modes which are responsible for the THz absorption peaks were decomposed for better understanding the characters of these low-frequency modes. The result suggests translational motion is the dominant component for water molecules in THz region. Evolution of the THz spectrum of INA-H I during dehydration provides direct evidence of the variations of crystal structure. Based on the THz measurements, a two-step kinetics mode including first-rate reaction and three-dimensional nuclei growth is proposed. And we nure that the low-frequency vibrations of water molecules are the origin of dehydration process of hydrate.
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19
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Smith KA, Ramkumar SP, Du K, Xu X, Cheong SW, Gilbert Corder SN, Bechtel HA, Nowadnick EA, Musfeldt JL. Real-Space Infrared Spectroscopy of Ferroelectric Domain Walls in Multiferroic h-(Lu,Sc)FeO 3. ACS APPLIED MATERIALS & INTERFACES 2023; 15:7562-7571. [PMID: 36715538 DOI: 10.1021/acsami.2c19600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
We employ synchrotron-based near-field infrared spectroscopy to image the phononic properties of ferroelectric domain walls in hexagonal (h) Lu0.6Sc0.4FeO3, and we compare our findings with a detailed symmetry analysis, lattice dynamics calculations, and prior models of domain-wall structure. Rather than metallic and atomically thin as observed in the rare-earth manganites, ferroelectric walls in h-Lu0.6Sc0.4FeO3 are broad and semiconducting, a finding that we attribute to the presence of an A-site substitution-induced intermediate phase that reduces strain and renders the interior of the domain wall nonpolar. Mixed Lu/Sc occupation on the A site also provides compositional heterogeneity over micron-sized length scales, and we leverage the fact that Lu and Sc cluster in different ratios to demonstrate that the spectral characteristics at the wall are robust even in different compositional regimes. This work opens the door to broadband imaging of physical and chemical heterogeneity in ferroics and represents an important step toward revealing the rich properties of these flexible defect states.
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Affiliation(s)
- Kevin A Smith
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Sriram P Ramkumar
- Department of Materials Science and Engineering, University of California, Merced, California 95343 United States
| | - Kai Du
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854 United States
| | - Xianghan Xu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854 United States
| | - Sang-Wook Cheong
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854 United States
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, New Jersey 08854 United States
| | - Stephanie N Gilbert Corder
- Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 United States
| | - Hans A Bechtel
- Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 United States
| | - Elizabeth A Nowadnick
- Department of Materials Science and Engineering, University of California, Merced, California 95343 United States
| | - Janice L Musfeldt
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States
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20
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Lin D, Ranjbar A, Li X, Huang X, Huang Y, Berger H, Forró L, Watanabe K, Taniguchi T, Belosludov RV, Kühne TD, Ding H, Bahramy MS, Xi X. Axial-Bonding-Driven Dimensionality Effect on the Charge-Density Wave in NbSe 2. NANO LETTERS 2022; 22:9389-9395. [PMID: 36416790 DOI: 10.1021/acs.nanolett.2c03280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
2H-NbSe2 is a prototypical charge-density-wave (CDW) system, exhibiting such a symmetry-breaking quantum ground state in its bulk and down to a single-atomic-layer limit. However, how this state depends on dimensionality and what governs the dimensionality effect remain controversial. Here, we experimentally demonstrate a robust 3 × 3 CDW phase in both freestanding and substrate-supported bilayer NbSe2, far above the bulk transition temperature. We exclude environmental effects and reveal a strong temperature and thickness dependence of Raman intensity from an axially vibrating A1g phonon mode, involving Se ions. Using first-principles calculations, we show that these result from a delicate but profound competition between the intra- and interlayer bonding formed between Se-pz orbitals. Our results suggest the crucial role of Se out-of-plane displacement in driving the CDW distortion, revealing the Se-dominated dimensionality effect and establishing a new perspective on the chemical bonding and mechanical stability in layered CDW materials.
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Affiliation(s)
- Dongjing Lin
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing210093, People's Republic of China
| | - Ahmad Ranjbar
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Theoretical Chemistry, University of Paderborn, Paderborn33098, Germany
| | - Xiaoxia Li
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing210093, People's Republic of China
| | - Xinyu Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing100081, People's Republic of China
| | - Yuan Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing100081, People's Republic of China
| | - Helmuth Berger
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, 1015Lausanne, Switzerland
| | - László Forró
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, 1015Lausanne, Switzerland
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba305-0044, Japan
| | | | - Thomas D Kühne
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Theoretical Chemistry, University of Paderborn, Paderborn33098, Germany
| | - Haifeng Ding
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing210093, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing210093, People's Republic of China
| | - Mohammad Saeed Bahramy
- Department of Physics and Astronomy, The University of Manchester, Oxford Road, ManchesterM13 9PL, United Kingdom
| | - Xiaoxiang Xi
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing210093, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing210093, People's Republic of China
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21
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Yang R, Ren X, Sun M. Optical spectra of bilayer borophene synthesized on Ag(111) film. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 282:121711. [PMID: 35940069 DOI: 10.1016/j.saa.2022.121711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/24/2022] [Accepted: 08/01/2022] [Indexed: 06/15/2023]
Abstract
In this paper, we theoretically investigated electronic structures, density of states (DOS), optical absorption, dielectric function of bilayer borophene synthesized on Ag(111) film, stimulated by the recent experimental report [Nature materials 2022, 21:35]. The results show that there is strong coupling between the Ag film and borophene layers. In the absorption spectra of BL borophene on Ag(111) substrate, there are strong absorption peaks in visible and infrared (IR) regions, which reveals strong plexciton peaks in visible and IR regions, which is contributed from the plasmonic and excitonic coupling interaction by the hybrid between Ag film and BL borophene. Raman modes of strongest vibration directly reflects the interlayer interaction of interlayer chemical bond. Our results not only provide physical insight into BL borophene synthesized on Ag(111) film, but also propose the potential applications of BL borophene in optoelectronic devices.
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Affiliation(s)
- Rui Yang
- School of Mathematics and Physics, Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Xin Ren
- Beijing No. 12 High School, Beijing 100071, China
| | - Mengtao Sun
- School of Mathematics and Physics, Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing 100083, China.
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22
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Radtke M, Hess C. Operando spectroelectrochemistry of bulk-exfoliated 2D SnS2 for anodes within alkali metal ion batteries reveals unusual tin (III) states. Front Chem 2022; 10:1038327. [DOI: 10.3389/fchem.2022.1038327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 10/04/2022] [Indexed: 11/13/2022] Open
Abstract
In this study we report an affordable synthesis and preparation of an electrochemically exfoliated few-layer 2-dimensional (2D) SnS2 anode material of high cycling durability and demonstrate its performance on the example of alkali metal batteries. The metalation mechanism consists of highly unusual and previously only speculated Sn (III)-state grasped by operando Raman spectroelectrochemistry aided by symmetry analysis. The prepared 2D material flakes were characterized by high resolution transmission electron microscopy, X-ray photoelectron and Raman spectroscopies. The operando Raman spectroelectrochemistry was chosen as a dedicated tool for the investigation of alkali-metal-ion intercalation (Li, Na, K), whereby the distortion of the A1g Raman active mode (out-of-plane S-Sn-S vibration) during battery charging exhibited a substantial dependence on the electrochemically applied potential. As a result of the structural dynamics a considerable Raman red-shift of 17.6 cm−1 was observed during metalation. Linewidth changes were used to evaluate the expansion caused by metalation, which in case of sodium and potassium were found to be minimal compared to lithium. Based on the spectroscopic and electrochemical results, a mechanism for the de-/intercalation of lithium, sodium and potassium is proposed which includes alloying in few-layer 2D SnS2 materials and the generation of point-defects.
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23
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Structural Dynamics, Phonon Spectra and Thermal Transport in the Silicon Clathrates. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27196431. [PMID: 36234968 PMCID: PMC9572326 DOI: 10.3390/molecules27196431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 01/26/2023]
Abstract
The potential of thermoelectric power to reduce energy waste and mitigate climate change has led to renewed interest in "phonon-glass electron-crystal" materials, of which the inorganic clathrates are an archetypal example. In this work we present a detailed first-principles modelling study of the structural dynamics and thermal transport in bulk diamond Si and five framework structures, including the reported Si Clathrate I and II structures and the recently-synthesised oC24 phase, with a view to understanding the relationship between the structure, lattice dynamics, energetic stability and thermal transport. We predict the IR and Raman spectra, including ab initio linewidths, and identify spectral signatures that could be used to confirm the presence of the different phases in material samples. Comparison of the energetics, including the contribution of the phonons to the finite-temperature Helmholtz free energy, shows that the framework structures are metastable, with the energy differences to bulk Si dominated by differences in the lattice energy. Thermal-conductivity calculations within the single-mode relaxation-time approximation show that the framework structures have significantly lower κlatt than bulk Si, which we attribute quantitatively to differences in the phonon group velocities and lifetimes. The lifetimes vary considerably between systems, which can be largely accounted for by differences in the three-phonon interaction strengths. Notably, we predict a very low κlatt for the Clathrate-II structure, in line with previous experiments but contrary to other recent modelling studies, which motivates further exploration of this system.
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24
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The Crystal Structure of Carbonic Acid. INORGANICS 2022. [DOI: 10.3390/inorganics10090132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Ubiquitous carbonic acid, H2CO3, a key molecule in biochemistry, geochemistry, and also extraterrestrial chemistry, is known from a plethora of physicochemical studies. Its crystal structure has now been determined from neutron-diffraction data on a deuterated sample in a specially built hybrid clamped cell. At 1.85 GPa, D2CO3 crystallizes in the monoclinic space group P21/c with a = 5.392(2), b = 6.661(4), c = 5.690(1) Å, β = 92.66(3)°, Z = 4, with one symmetry-inequivalent anti-anti shaped D2CO3 molecule forming dimers, as previously predicted. Quantum chemistry evidences π bonding within the CO3 molecular core, very strong hydrogen bonding between the molecules, and a massive influence of the crystal field on all bonds; phonon calculations emphasize the locality of the vibrations, being rather insensitive to the extended structure.
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25
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Medvedeva JE, Sharma K, Bhattarai B, Bertoni MI. Hydrogen Behavior at Crystalline/Amorphous Interface of Transparent Oxide Semiconductor and Its Effects on Carrier Transport and Crystallization. ACS APPLIED MATERIALS & INTERFACES 2022; 14:39535-39547. [PMID: 35984223 DOI: 10.1021/acsami.2c09604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The role of disorder and particularly of the interfacial region between crystalline and amorphous phases of indium oxide in the formation of hydrogen defects with covalent (In-OH) or ionic (In-H-In) bonding are investigated using ab initio molecular dynamics and hybrid density-functional approaches. The results reveal that disorder stabilizes In-H-In defects even in the stoichiometric amorphous oxide and also promotes the formation of deep electron traps adjacent to In-OH defects. Furthermore, below-room-temperature fluctuations help switch interfacial In-H-In into In-OH, creating a new deep state in the process. This H-defect transformation limits not only the number of free carriers but also the grain size, as observed experimentally in heavily H-doped sputtered In2Ox. On the other hand, the presence of In-OH helps break O2 defects, abundant in the disordered indium oxide, and thus contributes to faster crystallization rates. The divergent electronic properties of the ionic vs covalent H defects─passivation of undercoordinated In atoms vs creation of new deep electron traps, respectively─and the different behavior of the two types of H defects during crystallization suggest that the resulting macroscopic properties of H-doped indium oxide are governed by the relative concentrations of the In-H-In and In-OH defects. The microscopic understanding of the H defect formation and properties developed in this work serves as a foundation for future research efforts to find ways to control H species during deposition.
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Affiliation(s)
- Julia E Medvedeva
- Department of Physics, Missouri University of Science & Technology, Rolla, Missouri 65409, United States
| | - Kapil Sharma
- Department of Physics, Missouri University of Science & Technology, Rolla, Missouri 65409, United States
| | - Bishal Bhattarai
- Department of Physics, Missouri University of Science & Technology, Rolla, Missouri 65409, United States
| | - Mariana I Bertoni
- Ira A. Fulton School of Engineering, Arizona State University, Tempe, Arizona 85281, United States
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26
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Rundle J, Leoni S. Layered Tin Chalcogenides SnS and SnSe: Lattice Thermal Conductivity Benchmarks and Thermoelectric Figure of Merit. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:14036-14046. [PMID: 36051253 PMCID: PMC9421910 DOI: 10.1021/acs.jpcc.2c02401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Tin sulfide (SnS) and tin selenide (SnSe) are attractive materials for thermoelectric conversion applications. Favorable small band gap, high carrier mobility, large Seebeck coefficient, and remarkably low lattice thermal conductivity are a consequence of their anisotropic crystal structure of symmetry Pnma , made of corrugated, black phosphorus-like layers. Their internal lattice dynamics combined with chemical bond softening in going from SnS to SnSe make for subtle effects on lattice thermal conductivity. Reliable prediction of phonon transport for these materials must therefore include many-body effects. Using first principles methods and a transferable tight-binding potential for frozen phonon calculations, here, we investigate the evolution of thermal lattice conductivity and thermoelectric figure of merit in Pnma -SnS and -SnSe, also including the high-temperature Cmcm -SnS phase. We show how thermal conductivity lowering in SnS at higher temperatures is largely due to dynamic phonon softening ahead of the Pnma - Cmcm structural phase transition. SnS becomes more similar to SnSe in its lifetime and mean free path profiles as it approaches its high-temperature Cmcm phase. The latter nonetheless intrinsically constraints phonon group velocity modules, preventing SnS to overtake SnSe. Our analysis provides important insights and computational benchmarks for optimization of thermoelectric materials via a more efficient computational strategy compared to previous ab initio attempts, one that can be easily transferred to larger systems for further thermoelectric materials nanoengineering. The good description of anharmonicity at higher temperatures inherent to the tight-binding potential yields calculated lattice conductivity values that are in very good agreement with experiments.
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27
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Morita K, Kumagai Y, Oba F, Walsh A. Switchable Electric Dipole from Polaron Localization in Dielectric Crystals. PHYSICAL REVIEW LETTERS 2022; 129:017601. [PMID: 35841557 DOI: 10.1103/physrevlett.129.017601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 06/05/2022] [Indexed: 06/15/2023]
Abstract
Ferroelectricity in crystals is associated with the displacement of ions or rotations of polar units. Here we consider the dipole created by donor doping (D^{+}) and the corresponding bound polaron (e^{-}). A dipole of 6.15 Debye is predicted, from Berry phase analysis, in the Ruddlesden-Popper phase of Sr_{3}Ti_{2}O_{7}. A characteristic double-well potential is formed, which persists for high doping densities. The effective Hubbard U interaction can vary the defect state from metallic, a two-dimensional polaron, through to a zero-dimensional polaron. The ferroelectriclike behavior reported here is localized and distinct from conventional spontaneous lattice polarization.
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Affiliation(s)
- Kazuki Morita
- Department of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Yu Kumagai
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Fumiyasu Oba
- Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
- Materials Research Center for Element Strategy, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Aron Walsh
- Department of Materials, Imperial College London, London SW7 2AZ, United Kingdom
- Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Korea
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28
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Brenner T, Grumet M, Till P, Asher M, Zeier WG, Egger DA, Yaffe O. Anharmonic Lattice Dynamics in Sodium Ion Conductors. J Phys Chem Lett 2022; 13:5938-5945. [PMID: 35731950 PMCID: PMC9251760 DOI: 10.1021/acs.jpclett.2c00904] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
We employ terahertz-range temperature-dependent Raman spectroscopy and first-principles lattice dynamical calculations to show that the undoped sodium ion conductors Na3PS4 and isostructural Na3PSe4 both exhibit anharmonic lattice dynamics. The anharmonic effects in the compounds involve coupled host lattice-Na+ ion dynamics that drive the tetragonal-to-cubic phase transition in both cases, but with a qualitative difference in the anharmonic character of the transition. Na3PSe4 shows an almost purely displacive character with the soft modes disappearing in the cubic phase as the change in symmetry shifts these modes to the Raman-inactive Brillouin zone boundary. Na3PS4 instead shows an order-disorder character in the cubic phase, with the soft modes persisting through the phase transition and remaining Raman active in the cubic phase, violating Raman selection rules for that phase. Our findings highlight the important role of coupled host lattice-mobile ion dynamics in vibrational instabilities that are coincident with the exceptional conductivity of these Na+ ion conductors.
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Affiliation(s)
- Thomas
M. Brenner
- Department
of Chemical and Biological Physics, Weizmann
Institute of Science, Rehovot 76100, Israel
| | - Manuel Grumet
- Department
of Physics, Technical University of Munich, 85748 Garching, Germany
| | - Paul Till
- Institute
for Inorganic and Analytical Chemistry, University of Muenster, 48149 Münster, Germany
| | - Maor Asher
- Department
of Chemical and Biological Physics, Weizmann
Institute of Science, Rehovot 76100, Israel
| | - Wolfgang G. Zeier
- Institute
for Inorganic and Analytical Chemistry, University of Muenster, 48149 Münster, Germany
| | - David A. Egger
- Department
of Physics, Technical University of Munich, 85748 Garching, Germany
| | - Omer Yaffe
- Department
of Chemical and Biological Physics, Weizmann
Institute of Science, Rehovot 76100, Israel
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29
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Kashyap S, Batra K. Structural, electronic, thermodynamic and optical properties of SnlSemSn clusters: A DFT study. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2022.111501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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30
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Johnson D, Lai HE, Hansen K, Balbuena PB, Djire A. Hydrogen evolution reaction mechanism on Ti 3C 2 MXene revealed by in situ/operando Raman spectroelectrochemistry. NANOSCALE 2022; 14:5068-5078. [PMID: 35293922 DOI: 10.1039/d2nr00222a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
MXenes have shown great promise as electrocatalysts for the hydrogen evolution reaction (HER), but their mechanism is still poorly understood. Currently, the benchmark Ti3C2 MXene suffers from a large overpotential. In order to reduce this overpotential, modifications must be made to the structure to increase the reaction rate of the H+/e- coupled transfer steps. These modifications heavily depend on understanding the HER mechanism. To remedy this, in situ/operando Raman spectroelectrochemistry combined with density functional theory (DFT) calculations are utilized to probe the HER mechanism of the Ti3C2 MXene catalyst in aqueous media. In acidic electrolytes, the -O- termination groups are protonated to form Ti-OH bonds, followed by protonation of the adjacent Ti site, leading to H2 formation. DFT calculations show that the large overpotential is due to the lack of an optimum balance between O and Ti sites. In neutral electrolytes, H2O reduction occurs on the surface and leads to surface protonation, followed by H2 formation. This results in an overcharging of the structure that leads to the observed large HER overpotential. This study provides new insights into the HER mechanisms of MXene catalysts and a pathway forward to design efficient and cost-effective catalysts for HER and related electrochemical energy conversion systems.
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Affiliation(s)
- Denis Johnson
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Hao-En Lai
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Kyle Hansen
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Perla B Balbuena
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, USA.
- Department of Chemistry, Texas A&M University, Texas A&M University, College Station, TX 77843, USA
- Department of Material Science and Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Abdoulaye Djire
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, USA.
- Department of Material Science and Engineering, Texas A&M University, College Station, TX 77843, USA
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31
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Park D, Kim M, Kim J. Strongly Coupled Tin(IV) Sulfide-MultiWalled Carbon Nanotube Hybrid Composites and Their Enhanced Thermoelectric Properties. Inorg Chem 2022; 61:3723-3729. [PMID: 35179362 DOI: 10.1021/acs.inorgchem.1c03953] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Herein, tin(IV) sulfide (SnS2) and multiwalled carbon nanotube (MWCNT) composites are fabricated via a simple solution-mixing method in a hydrothermal reactor. SnS2 is closely coupled to the MWCNT surface, thus forming a coaxial nanostructure. Examination by X-ray photoelectron spectroscopy and scanning transmission electron microscopy indicates that the strong interface between SnS2 and the MWCNTs in the composite material is due to the formation of Sn-O and Sn-S bonds. In addition, an examination of the temperature-dependent thermoelectric (TE) properties demonstrates that the SnS2-MWCNT hybrid composite with 3 wt % MWCNTs exhibits the maximum power factor of ∼91.34 μW/(m·K2) at 500 K, which is ∼50 times larger than that of the pristine SnS2. These results highlight the fabrication and enhanced TE properties of hybrid composites via the coupling of SnS2 and MWCNTs.
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Affiliation(s)
- Dabin Park
- School of Chemical Engineering & Materials Science, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Minsu Kim
- School of Chemical Engineering & Materials Science, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Jooheon Kim
- School of Chemical Engineering & Materials Science, Chung-Ang University, Seoul 06974, Republic of Korea.,Department of Advance Materials Engineering, Chung-Ang University, Anseong 17546, Republic of Korea.,Department of Intelligent Energy and Industry, Graduate School, Chung-Ang University, Seoul 06974, Republic of Korea
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32
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Li Y, Sun Y, Li Q, Lei J, Yang B, Shen Y, Cai Y, Deng X. Study of temperature-dependent terahertz spectra of isonicotinamide in the form I using the quasi-harmonic approximation. Chemphyschem 2022; 23:e202100849. [PMID: 35098625 DOI: 10.1002/cphc.202100849] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/20/2022] [Indexed: 11/08/2022]
Abstract
Anharmonicity of molecular vibrational motions is closely associated with the thermal property of crystals. However, the origin of anharmonicity is still not fully understood. Low-frequency vibrations, which are usually defined in the terahertz (THz) range, show excellent sensitivity to anharmonicity. In this work, anharmonicity of isonicotinamide in the form I was investigated by using temperature-dependent terahertz time-domain spectroscopy and quasi-harmonic approximation (QHA) approach at PBE-D3 and PBE-MBD levels. Both DFT calculations suggest the variation of p-p stacking conformation dominates in the thermal expansion of unit cell. The frequency shifts of the modes in THz range obtained by QHA approach are found to be qualitatively consistent with the observation, demonstrating QHA approach is a useful tool for the interpretation of frequency shifts of modes induced by temperature.
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Affiliation(s)
- Yin Li
- Nanchang University, Department of Physics, Nanchang, CHINA
| | - Yiwen Sun
- Shenzhen University, School of Biomedical Engineering, Shenzhen, CHINA
| | - Qiqi Li
- Shenzhen University, School of Biomedical Engineering, Shenzhen, CHINA
| | - Jiangtao Lei
- Nanchang University, Institute of Space Science and Technology, Nanchang, CHINA
| | - Bo Yang
- Nanchang University, Department of Materials and Chemicals, Nanchang, CHINA
| | - Yun Shen
- Nanchang University, Department of Physics, Nanchang, CHINA
| | - Yingxiang Cai
- Nanchang University, Department of Physics, Nanchang, CHINA
| | - Xiaohua Deng
- Nanchang University, department of physics, Xuefu Avenue 999, Nanchang City, Jiangxi Province, 330031, Nanchang, CHINA
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33
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Li T, Zhang X, Zeng Z. Factors affecting the electron-phonon coupling in FeSe under pressure. Phys Chem Chem Phys 2021; 23:25107-25113. [PMID: 34752592 DOI: 10.1039/d1cp02749b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydrostatic pressure on superconductor FeSe increases the Wyckoff position, zSe, and decreases lattice constants. However, previously only the increasing of zSe was emphasized to be important in determining the electron-phonon coupling. We explicitly study each of the two factors individually to understand its influence on the electron-phonon coupling, band structure and Raman frequencies. We find that the increasing of zSe enhances the states around the Fermi level more, while the decreasing of the lattice constants enhances the phonon frequencies more, which together increase the electron-phonon coupling under pressure. Based on the above facts, we predict and prove that the in-plane biaxial strain on FeSe increases the electron-phonon coupling due to the increasing zSe value and the decreasing in-plane lattice constant. Our results uncover the factors affecting the increase of the electron-phonon coupling and provide information on how to enhance the electron-phonon coupling in FeSe.
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Affiliation(s)
- Tingting Li
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China. .,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
| | - Xiaoli Zhang
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China. .,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
| | - Zhi Zeng
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China. .,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
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34
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Pallavolu MR, Anil Kumar Y, Mani G, Alshgari RA, Ouladsmane M, Joo SW. Facile fabrication of novel heterostructured tin disulfide (SnS2)/tin sulfide (SnS)/N-CNO composite with improved energy storage capacity for high-performance supercapacitors. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2021.115695] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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35
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Rahim W, Skelton JM, Scanlon DO. Ca 4Sb 2O and Ca 4Bi 2O: two promising mixed-anion thermoelectrics. JOURNAL OF MATERIALS CHEMISTRY. A 2021; 9:20417-20435. [PMID: 34671477 PMCID: PMC8454491 DOI: 10.1039/d1ta03649a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
The environmental burden of fossil fuels and the rising impact of global warming have created an urgent need for sustainable clean energy sources. This has led to widespread interest in thermoelectric (TE) materials to recover part of the ∼60% of global energy currently wasted as heat as usable electricity. Oxides are particularly attractive as they are thermally stable, chemically inert, and formed of earth-abundant elements, but despite intensive efforts there have been no reports of oxide TEs matching the performance of flagship chalcogenide materials such as PbTe, Bi2Te3 and SnSe. A number of ternary X4Y2Z mixed-anion systems, including oxides, have predicted band gaps in the useful range for several renewable-energy applications, including as TEs, and some also show the complex crystal structures indicative of low lattice thermal conductivity. In this study, we use ab initio calculations to investigate the TE performance of two structurally-similar mixed-anion oxypnictides, Ca4Sb2O and Ca4Bi2O. Electronic-structure and band-alignment calculations using hybrid density-functional theory (DFT), including spin-orbit coupling, suggest that both materials are likely to be p-type dopable with large charge-carrier mobilities. Lattice-dynamics calculations using third-order perturbation theory predict ultra-low lattice thermal conductivities of ∼0.8 and ∼0.5 W m-1 K-1 above 750 K. Nanostructuring to a crystal grain size of 20 nm is predicted to further reduce the room temperature thermal conductivity by around 40%. Finally, we use the electronic- and thermal-transport calculations to estimate the thermoelectric figure of merit ZT, and show that with p-type doping both oxides could potentially serve as promising earth-abundant oxide TEs for high-temperature applications.
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Affiliation(s)
- Warda Rahim
- Department of Chemistry, University College London 20 Gordon Street London WC1H 0AJ UK
- Thomas Young Centre, University College London Gower Street London WC1E 6BT UK
| | - Jonathan M Skelton
- Department of Chemistry, University of Manchester Oxford Road Manchester M13 9PL UK
| | - David O Scanlon
- Department of Chemistry, University College London 20 Gordon Street London WC1H 0AJ UK
- Thomas Young Centre, University College London Gower Street London WC1E 6BT UK
- Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus Didcot Oxfordshire OX11 0DE UK
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36
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Cole-Filipiak NC, Knepper R, Wood M, Ramasesha K. Mode-Selective Vibrational Energy Transfer Dynamics in 1,3,5-Trinitroperhydro-1,3,5-triazine (RDX) Thin Films. J Phys Chem A 2021; 125:7788-7802. [PMID: 34464533 DOI: 10.1021/acs.jpca.1c04800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The coupling of inter- and intramolecular vibrations plays a critical role in initiating chemistry during the shock-to-detonation transition in energetic materials. Herein, we report on the subpicosecond to subnanosecond vibrational energy transfer (VET) dynamics of the solid energetic material 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) by using broadband, ultrafast infrared transient absorption spectroscopy. Experiments reveal VET occurring on three distinct time scales: subpicosecond, 5 ps, and 200 ps. The ultrafast appearance of signal at all probed modes in the mid-infrared suggests strong anharmonic coupling of all vibrations in the solid, whereas the long-lived evolution demonstrates that VET is incomplete, and thus thermal equilibrium is not attained, even on the 100 ps time scale. Density functional theory and classical molecular dynamics simulations provide valuable insights into the experimental observations, revealing compression-insensitive time scales for the initial VET dynamics of high-frequency vibrations and drastically extended relaxation times for low-frequency phonon modes under lattice compression. Mode selectivity of the longest dynamics suggests coupling of the N-N and axial NO2 stretching modes with the long-lived, excited phonon bath.
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Affiliation(s)
- Neil C Cole-Filipiak
- Combustion Research Facility, Sandia National Laboratories, Livermore, California 94550, United States
| | - Robert Knepper
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Mitchell Wood
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Krupa Ramasesha
- Combustion Research Facility, Sandia National Laboratories, Livermore, California 94550, United States
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Fundamental Aspects and Comprehensive Review on Physical Properties of Chemically Grown Tin-Based Binary Sulfides. NANOMATERIALS 2021; 11:nano11081955. [PMID: 34443785 PMCID: PMC8402085 DOI: 10.3390/nano11081955] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 07/21/2021] [Accepted: 07/26/2021] [Indexed: 11/17/2022]
Abstract
The rapid research progress in tin-based binary sulfides (SnxSy = o-SnS, c-SnS, SnS2, and Sn2S3) by the solution process has opened a new path not only for photovoltaics to generate clean energy at ultra-low costs but also for photocatalytic and thermoelectric applications. Fascinated by their prosperous developments, a fundamental understanding of the SnxSy thin film growth with respect to the deposition parameters is necessary to enhance the film quality and device performance. Therefore, the present review article initially delivers all-inclusive information such as structural characteristics, optical characteristics, and electrical characteristics of SnxSy. Next, an overview of the chemical bath deposition of SnxSy thin films and the influence of each deposition parameter on the growth and physical properties of SnxSy are interestingly outlined.
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New Insights into the Crystal Chemistry of Elpidite, Na 2Zr[Si 6O 15]·3H 2O and (Na 1+YCa x□ 1-X-Y) Σ=2Zr[Si 6O 15]·(3-X)H 2O, and Ab Initio Modeling of IR Spectra. MATERIALS 2021; 14:ma14092160. [PMID: 33922768 PMCID: PMC8122974 DOI: 10.3390/ma14092160] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 11/16/2022]
Abstract
Elpidite belongs to a special group of microporous zirconosilicates, which are of great interest due to their capability to uptake various molecules and ions, e.g., some radioactive species, in their structural voids. The results of a combined electron probe microanalysis and single-crystal X-ray diffraction study of the crystals of elpidite from Burpala (Russia) and Khan-Bogdo (Mongolia) deposits are reported. Some differences in the chemical compositions are observed and substitution at several structural positions within the structure of the compounds are noted. Based on the obtained results, a detailed crystal–chemical characterization of the elpidites under study was carried out. Three different structure models of elpidite were simulated: Na2ZrSi6O15·3H2O (related to the structure of Russian elpidite), partly Ca-replaced Na1.5Ca0.25ZrSi6O15·2.75H2O (close to elpidite from Mongolia), and a hypothetical CaZrSi6O15·2H2O. The vibration spectra of the models were obtained and compared with the experimental one, taken from the literature. The strong influence of water molecule vibrations on the shape of IR spectra of studied structural models of elpidite is discussed in the paper.
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Yan W, Fuh HR, Lv Y, Chen KQ, Tsai TY, Wu YR, Shieh TH, Hung KM, Li J, Zhang D, Ó Coileáin C, Arora SK, Wang Z, Jiang Z, Chang CR, Wu HC. Giant gauge factor of Van der Waals material based strain sensors. Nat Commun 2021; 12:2018. [PMID: 33795697 PMCID: PMC8016834 DOI: 10.1038/s41467-021-22316-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
There is an emergent demand for high-flexibility, high-sensitivity and low-power strain gauges capable of sensing small deformations and vibrations in extreme conditions. Enhancing the gauge factor remains one of the greatest challenges for strain sensors. This is typically limited to below 300 and set when the sensor is fabricated. We report a strategy to tune and enhance the gauge factor of strain sensors based on Van der Waals materials by tuning the carrier mobility and concentration through an interplay of piezoelectric and photoelectric effects. For a SnS2 sensor we report a gauge factor up to 3933, and the ability to tune it over a large range, from 23 to 3933. Results from SnS2, GaSe, GeSe, monolayer WSe2, and monolayer MoSe2 sensors suggest that this is a universal phenomenon for Van der Waals semiconductors. We also provide proof of concept demonstrations by detecting vibrations caused by sound and capturing body movements.
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Affiliation(s)
- Wenjie Yan
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Huei-Ru Fuh
- Department of Physics, National Taiwan University, Taipei, Taiwan
- Department of Chemical Engineering & Materials Science, Yuan Ze University, Taoyuan City, Taiwan
| | - Yanhui Lv
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Ke-Qiu Chen
- Department of Applied Physics, School of Physics and Electronics, Hunan University, Changsha, P. R. China
| | - Tsung-Yin Tsai
- Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
| | - Yuh-Renn Wu
- Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
| | - Tung-Ho Shieh
- Department of Intelligent Robotics Engineering, Kun-Shan University, Tainan, Taiwan
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan.
| | - Juncheng Li
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Duan Zhang
- Elementary Educational College, Beijing key Laboratory for Nano-Photonics and Nano-Structure, Capital Normal University, Beijing, P. R. China
| | - Cormac Ó Coileáin
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER), School Chemistry, Trinity College Dublin, Dublin, Ireland
| | - Sunil K Arora
- Centre for Nanoscience and Nanotechnology, Panjab University, Chandigarh, India
| | - Zhi Wang
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Zhaotan Jiang
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University, Taipei, Taiwan
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China.
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40
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Bi T, Shamp A, Terpstra T, Hemley RJ, Zurek E. The Li-F-H ternary system at high pressures. J Chem Phys 2021; 154:124709. [PMID: 33810644 DOI: 10.1063/5.0041490] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Evolutionary crystal structure prediction searches have been employed to explore the ternary Li-F-H system at 300 GPa. Metastable phases were uncovered within the static lattice approximation, with LiF3H2, LiF2H, Li3F4H, LiF4H4, Li2F3H, and LiF3H lying within 50 meV/atom of the 0 K convex hull. All of these phases contain HnFn+1 - (n = 1, 2) anions and Li+ cations. Other structural motifs such as LiF slabs, H3 + molecules, and Fδ- ions are present in some of the low enthalpy Li-F-H structures. The bonding within the HnFn+1 - molecules, which may be bent or linear, symmetric or asymmetric, is analyzed. The five phases closest to the hull are insulators, while LiF3H is metallic and predicted to have a vanishingly small superconducting critical temperature. Li3F4H is predicted to be stable at zero pressure. This study lays the foundation for future investigations of the role of temperature and anharmonicity on the stability and properties of compounds and alloys in the Li-F-H ternary system.
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Affiliation(s)
- Tiange Bi
- Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260-3000, USA
| | - Andrew Shamp
- Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260-3000, USA
| | - Tyson Terpstra
- Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260-3000, USA
| | - Russell J Hemley
- Departments of Physics and Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, USA
| | - Eva Zurek
- Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260-3000, USA
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Synthesis and Characterization of π-SnS Nanoparticles and Corresponding Thin Films. NANOMATERIALS 2021; 11:nano11030767. [PMID: 33803574 PMCID: PMC8002930 DOI: 10.3390/nano11030767] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 12/05/2022]
Abstract
Tin sulfide polymorph (π-SnS) nanoparticles exhibit promising optoelectrical characteristics for photovoltaic and hydrogen production performance, mainly because of the possibility of tuning their properties by adjusting the synthesis conditions. This study demonstrates a chemical approach to synthesize π-SnS nanoparticles and the engineering of their properties by altering the Sn precursor concentration (from 0.04 M to 0.20 M). X-ray diffraction and Raman studies confirmed the presence of pure cubic SnS phase nanoparticles with good crystallinity. SEM images indicated the group of cloudy shaped grains, and XPS results confirmed the presence of Sn and S in the synthesized nanoparticles. Optical studies revealed that the estimated energy bandgap values of the as-synthesized π-SnS nanoparticles varied from 1.52 to 1.68 eV. This work highlights the effects of the Sn precursor concentration on the properties of the π-SnS nanoparticles and describes the bandgap engineering process. Optimized π-SnS nanoparticles were used to deposit nanocrystalline π-SnS thin films using the drop-casting technique, and their physical properties were improved by annealing (300 °C for 2 h).
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42
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Xu L, Li Y, Jing P, Xu G, Zhou Q, Cai Y, Deng X. Terahertz spectroscopic characterizations and DFT calculations of indomethacin cocrystals with nicotinamide and saccharin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 249:119309. [PMID: 33341744 DOI: 10.1016/j.saa.2020.119309] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 06/12/2023]
Abstract
Co-crystallization is an effective strategy to improve the drug properties such as solubility and stability. However, its thermodynamic backgrounds, especially lattice vibration, haven't been fully understood. In this work, indomethacin (IND) cocrystals formed with nicotinamide (NIC) and saccharin (SAC) are successfully characterized by using terahertz spectroscopy. DFT calculations at PBE-D3 level with and without constrained unit cell are performed to predict the absorption peaks at spectral range. The results suggest that the DFT calculations with constrained unit cell achieve a better agreement with experimental observations. Based on the optimized geometries and calculated phonons, the thermodynamic contributions from lattice vibrations to cocrystal formations are further evaluated. The findings reveal that the vibrational energy plays a comparable role with electronic energy, but has an opposite impact on these two cocrystal formations.
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Affiliation(s)
- Li Xu
- Department of Chemical Engineering and Technology, School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Yin Li
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China.
| | - Peixin Jing
- Department of Chemical Engineering and Technology, School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Guohao Xu
- Department of Chemical Engineering and Technology, School of Chemistry, Biology and Materials Science, East China University of Technology, Guanglan Avenue 418, Nanchang City 330013, China
| | - Qi Zhou
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Yingxiang Cai
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
| | - Xiaohua Deng
- Department of Physics, School of Sciences, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China; Institute of Space Science and Technology, Nanchang University, Xuefu Avenue 999, Nanchang City 330031, China
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43
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Huang H, Yang G, Yu J, Zhang J, Xia Y, Wang K, Liang C, Gan Y, He X, Zhang W. One-pot synthesis of nanocrystalline SnS@tremella-like porous carbon by supercritical CO2 method for excellent sodium storage performance. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.137933] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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44
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Bajaj N, Roy AP, Khandelwal A, Chattopadhyay MK, Sathe V, Mishra SK, Mittal R, Babu PD, Le MD, Niedziela JL, Bansal D. Magnetoelastic coupling and spin contributions to entropy and thermal transport in biferroic yttrium orthochromite . JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:125702. [PMID: 33378273 DOI: 10.1088/1361-648x/abd781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
Direct engineering of material properties through exploitation of spin, phonon, and charge-coupled degrees of freedom is an active area of development in materials science. However, the relative contribution of the competing orders to controlling the desired behavior is challenging to decipher. In particular, the independent role of phonons, magnons, and electrons, quasiparticle coupling, and relative contributions to the phase transition free energy largely remain unexplored, especially for magnetic phase transitions. Here, we study the lattice and magnetic dynamics of biferroic yttrium orthochromite using Raman, infrared, and inelastic neutron spectroscopy techniques, supporting our experimental results with first-principles lattice dynamics and spin-wave simulations across the antiferromagnetic transition atTN∼ 138 K. Spectroscopy data and simulations together with the heat capacity (Cp) measurements, allow us to quantify individual entropic contributions from phonons (0.01 ± 0.01kBatom-1), dilational (0.03 ± 0.01kBatom-1), and magnons (0.11 ± 0.01kBatom-1) acrossTN. High-resolution phonon measurements conducted in a magnetic field show that anomalousT-dependence of phonon energies acrossTNoriginates from magnetoelastic coupling. Phonon scattering is primarily governed by the phonon-phonon coupling, with little contribution from magnon-phonon coupling, short-range spin correlations, or magnetostriction effects; a conclusion further supported by our thermal conductivity measurements conducted up to 14 T, and phenomenological modeling.
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Affiliation(s)
- Naini Bajaj
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
| | - Aditya Prasad Roy
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
| | - Ashish Khandelwal
- Free Electron Laser Utilization Laboratory, Raja Ramanna Centre for Advanced Technology, Indore, MP 452013, India
| | - M K Chattopadhyay
- Free Electron Laser Utilization Laboratory, Raja Ramanna Centre for Advanced Technology, Indore, MP 452013, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, MH 400094, India
| | - Vasant Sathe
- UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore, MP 452001, India
| | - Sanjay K Mishra
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, MH 400085, India
| | - Ranjan Mittal
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, MH 400085, India
| | - Peram Delli Babu
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, MH 400085, India
| | - Manh Duc Le
- ISIS facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, Oxfordshire, United Kingdom
| | - Jennifer L Niedziela
- Nuclear Nonproliferation Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
| | - Dipanshu Bansal
- Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai, MH 400076, India
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45
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Varadwaj PR. A 2AgCrCl 6 (A = Li, Na, K, Rb, Cs) halide double perovskites: a transition metal-based semiconducting material series with appreciable optical characteristics. Phys Chem Chem Phys 2020; 22:24337-24350. [PMID: 33063074 DOI: 10.1039/d0cp01896a] [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
We have theoretically examined the geometries, electronic density of states and band structures of cubic and hexagonal A2AgCrCl6 (A = Cs, Rb, K, Na, Li) using meta-GGA SCAN-rVV10. The optimized lattice density was found to vary between 2.68 and 4.08 g cm-3 for cubic-A2AgCrCl6, with the fundamental electronic bandgap (direct) in the range of 0.66-0.69 eV. The cell density of hexagonal A2AgCrCl6 was between 2.97 and 3.93 g cm-3, but with an indirect bandgap of 0.93-1.02 eV. The valence band maximum and the conduction band minimum of A2AgCrCl6 were confirmed to be essentially of Cr(3d) character, but the contributions from the orbital states of Cl(3p) to the VBM were also appreciable. Cubic A2AgCrCl6 (A = Cs, Rb, K) was identified to possess genuine perovskite stoichiometry, evaluated using various geometry-based indices (viz. octahedral factor, tolerance factor, and global instability index). This was not so for A2AgCrCl6 (A = Na, Li), and was due to the small size of Na and Li cations that caused the critical strain of CrCl6 octahedra and a significant decrease in the cell volume. However, all the five A2AgCrCl6 displayed nearly similar optical properties, including the nature of the oscillator peaks in the dielectric function, absorption coefficient, photoconductivity, reflectivity, and Tauc spectra. The zero-limit of the refractive index was calculated around 2.25 and 2.00 for cubic and hexagonal A2AgCrCl6, respectively, and the extinction coefficient was very small for all cases. The nature of the optical bandgap and transition peaks discussed in this study of cubic and hexagonal Cs2AgCrCl6 agreed well with the experiment. The examination of phonon band dispersion led to the conclusion that cubic-A2AgCrCl6 (A = Cs, Rb) are the only halide double perovskites of the entire series that are dynamically stable.
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Affiliation(s)
- Pradeep R Varadwaj
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo 7-3-1, Tokyo 113-8656, Japan.
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Crovetto A, Xing Z, Fischer M, Nielsen R, Savory CN, Rindzevicius T, Stenger N, Scanlon DO, Chorkendorff I, Vesborg PCK. Experimental and First-Principles Spectroscopy of Cu 2SrSnS 4 and Cu 2BaSnS 4 Photoabsorbers. ACS APPLIED MATERIALS & INTERFACES 2020; 12:50446-50454. [PMID: 33108169 DOI: 10.1021/acsami.0c14578] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Cu2BaSnS4 (CBTS) and Cu2SrSnS4 (CSTS) semiconductors have been recently proposed as potential wide band gap photovoltaic absorbers. Although several measurements indicate that they are less affected by band tailing than their parent compound Cu2ZnSnS4, their photovoltaic efficiencies are still low. To identify possible issues, we characterize CBTS and CSTS in parallel by a variety of spectroscopic methods complemented by first-principles calculations. Two main problems are identified in both materials. The first is the existence of deep defect transitions in low-temperature photoluminescence, pointing to a high density of bulk recombination centers. The second is their low electron affinity, which emphasizes the need for an alternative heterojunction partner and electron contact. We also find a tendency for downward band bending at the surface of both materials. In CBTS, this effect is sufficiently large to cause carrier-type inversion, which may enhance carrier separation and mitigate interface recombination. Optical absorption at room temperature is exciton-enhanced in both CBTS and CSTS. Deconvolution of excitonic effects yields band gaps that are about 100 meV higher than previous estimates based on Tauc plots. Although the two investigated materials are remarkably similar in an idealized, defect-free picture, the present work points to CBTS as a more promising absorber than CSTS for tandem photovoltaics.
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Affiliation(s)
- Andrea Crovetto
- SurfCat, DTU Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
- Department of Structure and Dynamics of Energy Materials, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin, Germany
| | - Zongda Xing
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
- Thomas Young Centre, University College London, Gower Street, London WC1E 6BT, U.K
| | - Moritz Fischer
- DTU Fotonik, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
- Center for Nanostructured Graphene (CNG), Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Rasmus Nielsen
- SurfCat, DTU Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Christopher N Savory
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
- Thomas Young Centre, University College London, Gower Street, London WC1E 6BT, U.K
| | - Tomas Rindzevicius
- DTU Health Technology, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Nicolas Stenger
- DTU Fotonik, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
- Center for Nanostructured Graphene (CNG), Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - David O Scanlon
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
- Thomas Young Centre, University College London, Gower Street, London WC1E 6BT, U.K
- Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K
| | - Ib Chorkendorff
- SurfCat, DTU Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Peter C K Vesborg
- SurfCat, DTU Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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Abstract
Agrellite, NaCa2Si4O10F, is a tubular silicate mineral which crystal structure is characterized by extended [Si8O20]8– tubes and has a two-dimensional channel system. The mineral is a representative of a complex silicate family which contains some structural voids but cannot be considered as microporous because of small channel widths. However, the channel system of such minerals is able to host single guest atoms, molecules or radicals which can affect their physical properties. Presently, the exact mechanism of such hosting is undetermined. However, such information could be quite useful for materials’ application as zeolites as well as for a better understanding of their formation mechanisms. In this work we couple X-ray diffraction, infrared (IR) spectroscopy and ab initio calculations to identify structural features in agrellite from Malyy Murun massif (Russia) caused by incorporation of either H2O or OH− into the channel system. We construct structural models of water-containing NaCa2Si4O10F and identified H2O positions. The derivation of H2O sites is based on simulation of IR-spectra. Infrared spectroscopy in combination with the ab initio calculation has proven to be an effective tool for the identification of the structural positions of hydroxyl anions (OH−) and neutral water groups (H2O) in minerals.
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48
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Kwon SH, Kim BH, Kim DW, Yoon H, Yoon YJ. Vastly enhanced photoresponsivities of phase-controlled tin sulfide thin films. NANOTECHNOLOGY 2020; 31:375702. [PMID: 32492662 DOI: 10.1088/1361-6528/ab991b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Herein, we reveal extraordinary enhancements in the photoresponsivities of tin sulfide (SnxSy) grown on SiO2/Si wafers through post-phase transformations induced by electron beam irradiation (EBI) and crystallization. Amorphous SnxSy thin films were formed by room-temperature sputtering, and as-deposited films were subsequently transformed into hexagonal SnS2 and orthorhombic SnS phases by EBI at 600 and 800 V respectively, for only one minute. The use of a low-energy electron beam was sufficient to fabricate a SnxSy photodetector, with no additional heating required. Less than 10 nm thick SnxSy films with well-defined layer structures and stable surface morphologies were obtained through EBI at 600 and 800 V. The resulting phase-controlled SnS thin-film photodetector prepared using 800 V-EBI exhibited a 40 000-fold increase in photoresponsivity; when illuminated by a 450 nm light source, the active SnS-layer-containing photodetector demonstrated a photoresponsivity of 33.2 mA W-1.
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Affiliation(s)
- Soon Hyeong Kwon
- Nanomaterials and Nanotechnology Center, Korea Institute of Ceramic Engineering and Technology (KICET), Jinju 52851, Republic of Korea
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49
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Lanigan-Atkins T, Yang S, Niedziela JL, Bansal D, May AF, Puretzky AA, Lin JYY, Pajerowski DM, Hong T, Chi S, Ehlers G, Delaire O. Extended anharmonic collapse of phonon dispersions in SnS and SnSe. Nat Commun 2020; 11:4430. [PMID: 32887880 PMCID: PMC7474096 DOI: 10.1038/s41467-020-18121-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 08/09/2020] [Indexed: 11/12/2022] Open
Abstract
The lattice dynamics and high-temperature structural transition in SnS and SnSe are investigated via inelastic neutron scattering, high-resolution Raman spectroscopy and anharmonic first-principles simulations. We uncover a spectacular, extreme softening and reconstruction of an entire manifold of low-energy acoustic and optic branches across a structural transition, reflecting strong directionality in bonding strength and anharmonicity. Further, our results solve a prior controversy by revealing the soft-mode mechanism of the phase transition that impacts thermal transport and thermoelectric efficiency. Our simulations of anharmonic phonon renormalization go beyond low-order perturbation theory and capture these striking effects, showing that the large phonon shifts directly affect the thermal conductivity by altering both the phonon scattering phase space and the group velocities. These results provide a detailed microscopic understanding of phase stability and thermal transport in technologically important materials, providing further insights on ways to control phonon propagation in thermoelectrics, photovoltaics, and other materials requiring thermal management.
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Affiliation(s)
- T Lanigan-Atkins
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - S Yang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - J L Niedziela
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - D Bansal
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - A F May
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - A A Puretzky
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - J Y Y Lin
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - D M Pajerowski
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - T Hong
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - S Chi
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - G Ehlers
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - O Delaire
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA.
- Department of Physics, Duke University, Durham, NC, USA.
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Vázquez-Fernández I, Mariotti S, Hutter OS, Birkett M, Veal TD, Hobson TDC, Phillips LJ, Danos L, Nayak PK, Snaith HJ, Xie W, Sherburne MP, Asta M, Durose K. Vacancy-Ordered Double Perovskite Cs 2TeI 6 Thin Films for Optoelectronics. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2020; 32:6676-6684. [PMID: 32952296 PMCID: PMC7497706 DOI: 10.1021/acs.chemmater.0c02150] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/09/2020] [Indexed: 05/29/2023]
Abstract
Alternatives to lead- and tin-based perovskites for photovoltaics and optoelectronics are sought that do not suffer from the disadvantages of toxicity and low device efficiency of present-day materials. Here we report a study of the double perovskite Cs2TeI6, which we have synthesized in the thin film form for the first time. Exhaustive trials concluded that spin coating CsI and TeI4 using an antisolvent method produced uniform films, confirmed as Cs2TeI6 by XRD with Rietveld analysis. They were stable up to 250 °C and had an optical band gap of ∼1.5 eV, absorption coefficients of ∼6 × 104 cm-1, carrier lifetimes of ∼2.6 ns (unpassivated 200 nm film), a work function of 4.95 eV, and a p-type surface conductivity. Vibrational modes probed by Raman and FTIR spectroscopy showed resonances qualitatively consistent with DFT Phonopy-calculated spectra, offering another route for phase confirmation. It was concluded that the material is a candidate for further study as a potential optoelectronic or photovoltaic material.
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Affiliation(s)
- Isabel Vázquez-Fernández
- Stephenson
Institute for Renewable Energy, Deptartment of Physics, University of Liverpool, Chadwick Building, Peach Street, Liverpool L69 7ZF, United Kingdom
| | - Silvia Mariotti
- Stephenson
Institute for Renewable Energy, Deptartment of Physics, University of Liverpool, Chadwick Building, Peach Street, Liverpool L69 7ZF, United Kingdom
| | - Oliver S. Hutter
- Department
of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle
upon Tyne NE1 8ST, United
Kingdom
| | - Max Birkett
- Stephenson
Institute for Renewable Energy, Deptartment of Physics, University of Liverpool, Chadwick Building, Peach Street, Liverpool L69 7ZF, United Kingdom
| | - Tim D. Veal
- Stephenson
Institute for Renewable Energy, Deptartment of Physics, University of Liverpool, Chadwick Building, Peach Street, Liverpool L69 7ZF, United Kingdom
| | - Theodore D. C. Hobson
- Stephenson
Institute for Renewable Energy, Deptartment of Physics, University of Liverpool, Chadwick Building, Peach Street, Liverpool L69 7ZF, United Kingdom
| | - Laurie J. Phillips
- Stephenson
Institute for Renewable Energy, Deptartment of Physics, University of Liverpool, Chadwick Building, Peach Street, Liverpool L69 7ZF, United Kingdom
| | - Lefteris Danos
- Department
of Chemistry, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - Pabitra K. Nayak
- Department
of Physics, Clarendon Laboratory, University
of Oxford, Oxford OX1 3PU, United Kingdom
- TIFR
Centre
for Interdisciplinary Sciences, Tata Institute
of Fundamental Research, Hyderabad 500107, India
| | - Henry J. Snaith
- Department
of Physics, Clarendon Laboratory, University
of Oxford, Oxford OX1 3PU, United Kingdom
| | - Wei Xie
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
| | - Matthew P. Sherburne
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
| | - Mark Asta
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
| | - Ken Durose
- Stephenson
Institute for Renewable Energy, Deptartment of Physics, University of Liverpool, Chadwick Building, Peach Street, Liverpool L69 7ZF, United Kingdom
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