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Li Y, Wei H, Chen L, Xie C, Ding H, Fang F, Chai Z, Huang Q. Regulating the Electronic Structure of MAX Phases Based on Rare Earth Element Sc to Enhance Electromagnetic Wave Absorption. ACS Nano 2024; 18:10019-10030. [PMID: 38545930 DOI: 10.1021/acsnano.3c11585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
MAX phases are highly promising materials for electromagnetic (EM) wave absorption because of their specific combination of metal and ceramic properties, making them particularly suitable for harsh environments. However, their higher matching thickness and impedance mismatching can limit their ability to attenuate EM waves. To address this issue, researchers have focused on regulating the electronic structure of MAX phases through structural engineering. In this study, we successfully synthesized a ternary MAX phase known as Sc2GaC MAX with the rare earth element Sc incorporated into the M-site sublayer, resulting in exceptional conductivity and impressive stability at high temperatures. The Sc2GaC demonstrates a strong reflection loss (RL) of -47.7 dB (1.3 mm) and an effective absorption bandwidth (EAB) of 5.28 GHz. It also achieves effective absorption of EM wave energy across a wide frequency range, encompassing the X and Ku bands. This exceptional performance is observed within a thickness range of 1.3 to 2.1 mm, making it significantly superior to other Ga-MAX phases. Furthermore, Sc2GaC exhibited excellent absorption performance even at elevated temperatures. After undergoing oxidation at 800 °C, it achieves a minimum RL of -28.3 dB. Conversely, when treated at 1400 °C under an argon atmosphere, Sc2GaC demonstrates even higher performance, with a minimum RL of -46.1 dB. This study highlights the potential of structural engineering to modify the EM wave absorption performance of the MAX phase by controlling its intrinsic electronic structure.
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Affiliation(s)
- Youbing Li
- Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, China
- Qianwan Institute of CNiTECH, Ningbo, Zhejiang 315336, China
| | - Haoshuai Wei
- Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
- Qianwan Institute of CNiTECH, Ningbo, Zhejiang 315336, China
| | - Lu Chen
- Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
- Qianwan Institute of CNiTECH, Ningbo, Zhejiang 315336, China
| | - Chaoyin Xie
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, China
| | - Haoming Ding
- Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
- Qianwan Institute of CNiTECH, Ningbo, Zhejiang 315336, China
| | - Fei Fang
- College of Digital Technology and Engineering, Ningbo University of Finance and Economics, Ningbo, Zhejiang 315201, China
| | - Zhifang Chai
- Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, China
- Qianwan Institute of CNiTECH, Ningbo, Zhejiang 315336, China
| | - Qing Huang
- Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
- Qianwan Institute of CNiTECH, Ningbo, Zhejiang 315336, China
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Fang L, Hu E, Hu X, Jiang Z, Shah MAKY, Wang J, Wang F. Development of a Core-Shell Heterojunction TiO2/SrTiO3 electrolyte with improved ionic conductivity. Chemphyschem 2022; 23:e202200170. [PMID: 35322910 DOI: 10.1002/cphc.202200170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Indexed: 11/07/2022]
Abstract
Lately, semiconductor-membrane fuel cells (SMFCs) have attained significant interest and great attention due to the deliverance of high performance at low operational temperatures, < 550 o C. This work has synthesized the nanocomposite core-shell heterostructure (TiO 2 -SrTiO 3- ) electrolyte powder by employing the simple hydrothermal method for the SMFC. The SrTiO 3 was grown in situ on the surface of TiO 2 to form a core-shell structure. A heterojunction mechanism based on the energy band structure is proposed to explain the ion transport pathway and promote protonic conductivity. The core-shell heterostructure (TiO 2 -SrTiO 3 ) was utilized as an electrolyte to reach the peak power density of 951 mW cm -2 with an open-circuit voltage of 1.075 V at 550 o C. The formation of core-shell heterostructure among TiO 2 and SrTiO 3 causes redistribution of charges and establishes a depletion region at the interface, which confined the protons' transport on the surface layer with accelerated ion transport and lower activation energy. The current work reveals novel insights to understand enhanced proton transport and unique methodology to develop low-temperature ceramic fuel cells with high performance.
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Affiliation(s)
- Li Fang
- Southeast University, School of Energy & Environment, CHINA
| | - Enyi Hu
- Southeast University, School of Energy & Environment, CHINA
| | - Xiaojian Hu
- PowerChina Huadong Engineering Corporation Limited, Power China, CHINA
| | - Zheng Jiang
- Southeast University, School of Energy & Environment, CHINA
| | | | - Jun Wang
- Southeast University, School of Energy & Environment, CHINA
| | - Faze Wang
- Southeast University, School of Energy & Environment, No.2 Sipailou, Nanjing, Jiangsu Province, 210096, Nanjing, CHINA
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Sakurai A, Ando K, Ashihara S. Ultrafast proton/deuteron dynamics in KTaO 3 observed with infrared pump-probe spectroscopy: Toward understanding of proton conduction mechanism in solid oxides. J Chem Phys 2018; 149:104502. [DOI: 10.1063/1.5040063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Atsunori Sakurai
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan
| | - Koji Ando
- Department of Information and Sciences, Tokyo Woman’s Christian University, 2-6-1 Zenpukuji, Suginami, Tokyo 167-8585, Japan
| | - Satoshi Ashihara
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan
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Iqbal AM, Jaffari GH, Saleemi M, Ceylan A. Relaxation dynamics and polydispersivity associated with defects and ferroelectric correlations in Ba-doped EuTiO 3. J Phys Condens Matter 2017; 29:465402. [PMID: 29053467 DOI: 10.1088/1361-648x/aa8b95] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We present the frequency- and temperature-dependent dielectric response of Eu1-x Ba x TiO3 (0 ⩽ x ⩽ 0.5) in detail. Excluding grain boundary effects, four relaxation mechanisms were observed. Relaxation dynamics were observed to arise due to hopping conduction associated with defects, namely oxygen vacancies as well as Eu3+ and Ti3+ ions. Dielectric relaxation analysis led to the identification of Ti ions in two different environments with different relaxation rates in the overall EuTiO3 perovskite structure. The emergence of another relaxation mechanism associated with ferroelectric order as a consequence of the formation of polar regions was also observed for higher Ba concentrations. The addition of Ba led to the identification of relaxation dynamics associated with hopping conduction between Eu ions, Ti ions (in the regions with and without oxygen vacancies) and with the formation of ferroelectric polar regions. Furthermore, the polydispersivity and relaxation times were extracted within the framework of the modified Debye model. Relaxation times have been observed to increase with a decrease in temperature while larger values of polydispersivity reveal a wide distribution of relaxation times due to the presence of lattice parameter and energy barrier distributions.
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Affiliation(s)
- Asad M Iqbal
- Department of Physics, Quaid-i-Azam University, Islamabad, Pakistan
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Canu G, Buscaglia V. Hydrothermal synthesis of strontium titanate: thermodynamic considerations, morphology control and crystallisation mechanisms. CrystEngComm 2017. [DOI: 10.1039/c7ce00834a] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The hydrothermal/solvothermal method is one of the most versatile synthetic routes for producing a large number of compounds. The thermodynamic aspects, the control of morphology and the crystallisation mechanisms are reviewed and discussed in this highlight, with special emphasis on the synthesis of SrTiO3, as a model system.
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Affiliation(s)
- Giovanna Canu
- Institute of Condensed Matter Chemistry and Technologies for Energy
- National Research Council
- I-16149 Genoa
- Italy
| | - Vincenzo Buscaglia
- Institute of Condensed Matter Chemistry and Technologies for Energy
- National Research Council
- I-16149 Genoa
- Italy
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Cheng S, Wang Y, Zhuang L, Xue J, Wei Y, Feldhoff A, Caro J, Wang H. A Dual-Phase Ceramic Membrane with Extremely High H2
Permeation Flux Prepared by Autoseparation of a Ceramic Precursor. Angew Chem Int Ed Engl 2016; 55:10895-8. [DOI: 10.1002/anie.201604035] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Shunfan Cheng
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
| | - Yanjie Wang
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
| | - Libin Zhuang
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
| | - Jian Xue
- Institute of Physical Chemistry and Electrochemistry; Leibniz University of Hannover; Callinstrasse 3A 30167 Hannover Germany
| | - Yanying Wei
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
- Institute of Physical Chemistry and Electrochemistry; Leibniz University of Hannover; Callinstrasse 3A 30167 Hannover Germany
| | - Armin Feldhoff
- Institute of Physical Chemistry and Electrochemistry; Leibniz University of Hannover; Callinstrasse 3A 30167 Hannover Germany
| | - Jürgen Caro
- Institute of Physical Chemistry and Electrochemistry; Leibniz University of Hannover; Callinstrasse 3A 30167 Hannover Germany
| | - Haihui Wang
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
- School of Chemical Engineering; The University of Adelaide; Adelaide SA 5005 Australia
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Cheng S, Wang Y, Zhuang L, Xue J, Wei Y, Feldhoff A, Caro J, Wang H. Eine zweiphasige Keramikmembran mit extrem hohem Wasserstoff-Fluss durch Entmischung einer keramischen Vorstufe. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Shunfan Cheng
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
| | - Yanjie Wang
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
| | - Libin Zhuang
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
| | - Jian Xue
- Institut für Physikalische Chemie und Elektrochemie; Gottfried Wilhelm Leibniz Universität Hannover; Callinstraße 3A 30167 Hannover Deutschland
| | - Yanying Wei
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
- Institut für Physikalische Chemie und Elektrochemie; Gottfried Wilhelm Leibniz Universität Hannover; Callinstraße 3A 30167 Hannover Deutschland
| | - Armin Feldhoff
- Institut für Physikalische Chemie und Elektrochemie; Gottfried Wilhelm Leibniz Universität Hannover; Callinstraße 3A 30167 Hannover Deutschland
| | - Jürgen Caro
- Institut für Physikalische Chemie und Elektrochemie; Gottfried Wilhelm Leibniz Universität Hannover; Callinstraße 3A 30167 Hannover Deutschland
| | - Haihui Wang
- School of Chemistry and Chemical Engineering; South China University of Technology; 510640 Guangzhou China
- School of Chemical Engineering; The University of Adelaide; Adelaide SA 5005 Australien
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Masuda N, Kobayashi Y, Hernandez O, Bataille T, Paofai S, Suzuki H, Ritter C, Ichijo N, Noda Y, Takegoshi K, Tassel C, Yamamoto T, Kageyama H. Hydride in BaTiO2.5H0.5: A Labile Ligand in Solid State Chemistry. J Am Chem Soc 2015; 137:15315-21. [PMID: 26575595 DOI: 10.1021/jacs.5b10255] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In synthesizing mixed anion oxides, direct syntheses have often been employed, usually involving high temperature and occasionally high pressure. Compared with these methods, here we show how the use of a titanium perovskite oxyhydride (BaTiO2.5H0.5) as a starting material enables new multistep low temperature topochemical routes to access mixed anion compounds. Similar to labile ligands in inorganic complexes, the lability of H(-) provides the necessary reactivity for syntheses, leading to reactions and products previously difficult to obtain. For example, BaTiO2.5N0.2 can be prepared with the otherwise inert N2 gas at 400-600 °C, in marked contrast with currently available oxynitride synthetic routes. F(-)/H(-) exchange can also be accomplished at 150 °C, yielding the oxyhydride-fluoride BaTi(O, H, F)3. For BaTiO2.4D0.3F0.3, we find evidence that further anionic exchange with OD(-) yields BaTiO2.4(D(-))0.26(OD(-))0.34, which implies stable coexistence of H(+) and H(-) at ambient conditions. Such an arrangement is thermodynamically unstable and would be difficult to realize otherwise. These results show that the labile nature of hydride imparts reactivity to oxide hosts, enabling it to participate in new multistep reactions and form new materials.
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Affiliation(s)
- Naoya Masuda
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan
| | - Yoji Kobayashi
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan.,PRESTO, Japan Science and Technology Agency (JST) , Kawaguchi-shi, Saitama 332-0012, Japan
| | - Olivier Hernandez
- Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 1 , Bâtiment 10B, Campus de Beaulieu, Rennes F-35042, France
| | - Thierry Bataille
- Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 1 , Bâtiment 10B, Campus de Beaulieu, Rennes F-35042, France
| | - Serge Paofai
- Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 1 , Bâtiment 10B, Campus de Beaulieu, Rennes F-35042, France
| | - Hajime Suzuki
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan
| | - Clemens Ritter
- Institut Laue-Langevin , 6, rue Jules Horowitz, Grenoble 38000, France
| | - Naoki Ichijo
- Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Yasuto Noda
- Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Kiyonori Takegoshi
- Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Cédric Tassel
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan
| | - Takafumi Yamamoto
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan
| | - Hiroshi Kageyama
- Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Nishikyo-ku, Kyoto 615-8510, Japan.,CREST, Japan Science and Technology Agency (JST) , Kawaguchi-shi, Saitama 332-0012, Japan
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Salman Z, Prokscha T, Amato A, Morenzoni E, Scheuermann R, Sedlak K, Suter A. Direct spectroscopic observation of a shallow hydrogenlike donor state in insulating SrTiO3. Phys Rev Lett 2014; 113:156801. [PMID: 25375730 DOI: 10.1103/physrevlett.113.156801] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Indexed: 06/04/2023]
Abstract
We present a direct spectroscopic observation of a shallow hydrogenlike muonium state in SrTiO(3) which confirms the theoretical prediction that interstitial hydrogen may act as a shallow donor in this material. The formation of this muonium state is temperature dependent and appears below ∼ 70K. From the temperature dependence we estimate an activation energy of ∼ 50 meV in the bulk and ∼ 23 meV near the free surface. The field and directional dependence of the muonium precession frequencies further supports the shallow impurity state with a rare example of a fully anisotropic hyperfine tensor. From these measurements we determine the strength of the hyperfine interaction and propose that the muon occupies an interstitial site near the face of the oxygen octahedron in SrTiO(3). The observed shallow donor state provides new insight for tailoring the electronic and optical properties of SrTiO(3)-based oxide interface systems.
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Affiliation(s)
- Z Salman
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - T Prokscha
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - A Amato
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - E Morenzoni
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - R Scheuermann
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - K Sedlak
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - A Suter
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
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Abstract
Understanding the fundamental properties of materials of relevance for alternative energy technologies is crucial in addressing the global challenge of cleaner sources of energy. This Perspective article aims to demonstrate the important role that neutron scattering now plays in advancing the state of the art of the basic understanding of proton conducting oxides, which show potential as electrolytes in next-generation intermediate temperature fuel cells. In particular, the breadth of neutron scattering work on perovskite structured oxides, which continue to be the most promising class of electrolytes for intermediate-temperature applications, is reviewed. Key fundamental properties that are addressed include structures, proton sites, hydrogen-bonding interactions, proton dynamics, and concentration of protons in materials. Furthermore, the perspectives for future neutron studies within this field of research are discussed.
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Affiliation(s)
- Maths Karlsson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
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Spahr EJ, Wen L, Stavola M, Boatner LA, Feldman LC, Tolk NH, Lüpke G. Proton tunneling: a decay channel of the O-H stretch mode in KTaO3. Phys Rev Lett 2009; 102:075506. [PMID: 19257689 DOI: 10.1103/physrevlett.102.075506] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Indexed: 05/27/2023]
Abstract
The vibrational lifetimes of the O-H and O-D stretch modes in the perovskite oxide KTaO3 are measured by pump-probe infrared spectroscopy. Both stretch modes are exceptionally long lived and exhibit a large "reverse" isotope effect, due to a phonon-assisted proton-tunneling process, which involves the O-Ta-O bending motion. The excited-state tunneling rate is found to be 7 orders of magnitude larger than from the ground state in the proton conducting oxide, BaCeO3 [Phys. Rev. B 60, R3713 (1999)].
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Affiliation(s)
- E J Spahr
- Department of Applied Science, College of William and Mary, Williamsburg, Virginia 23187, USA
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De Souza RA. The formation of equilibrium space-charge zones at grain boundaries in the perovskite oxide SrTiO3. Phys Chem Chem Phys 2009; 11:9939-69. [DOI: 10.1039/b904100a] [Citation(s) in RCA: 170] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Azad AK, Savaniu C, Tao S, Duval S, Holtappels P, Ibberson RM, Irvine JTS. Structural origins of the differing grain conductivity values in BaZr0.9Y0.1O2.95 and indication of novel approach to counter defect association. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b806190d] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Björketun ME, Sundell PG, Wahnström G. Structure and thermodynamic stability of hydrogen interstitials in BaZrO3perovskite oxide from density functional calculations. Faraday Discuss 2007; 134:247-65; discussion 315-29, 415-9. [PMID: 17326572 DOI: 10.1039/b602081j] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Density functional calculations have been used to study the electronic structure, preferred sites in the lattice, formation energies and vibrational frequencies for hydrogen interstitials in different charge states in the cubic phase of perovskite-structured BaZrO3. By combining ab initio results with thermodynamic modeling, defect formation at finite temperature and pressure has been investigated. We demonstrate how the site selectivity and spatial distribution of dopant atoms in the lattice can be affected by changes in the environmental conditions (atomic chemical potentials, oxygen partial pressure and temperature) used during processing of the material. In addition, we have calculated the thermodynamic parameters of the water uptake reaction for an acceptor-doped BaZrO3 crystal in equilibrium with a humid atmosphere. The interaction energies between a protonic defect and the investigated Ga, Gd, In, Nd, Sc, and Y dopants were found to be attractive, and we show that a simple model of defect association may reproduce an experimentally observed trend in the hydration enthalpy.
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Affiliation(s)
- Mårten E Björketun
- Department of Applied Physics, Chalmers University of Technology, S-412 96, Göteborg, Sweden.
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Kreuer KD, Paddison SJ, Spohr E, Schuster M. Transport in Proton Conductors for Fuel-Cell Applications: Simulations, Elementary Reactions, and Phenomenology. Chem Rev 2004; 104:4637-78. [PMID: 15669165 DOI: 10.1021/cr020715f] [Citation(s) in RCA: 1104] [Impact Index Per Article: 55.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Klaus-Dieter Kreuer
- Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, D-70569 Stuttgart, Germany.
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Affiliation(s)
- Gin-ya Adachi
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Osaka 565-0871, Japan
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SODA K, IIZUKA E, TSUCHIYA B, MORITA K, IWAHARA H. Isotope Effects in Diffusions of H and D in Hydrogen Isotope Exchange in Oxide Ceramics. J NUCL SCI TECHNOL 2002. [DOI: 10.1080/18811248.2002.9715203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Affiliation(s)
| | | | | | - Hiroyasu IWAHARA
- Center for Integrated Research in Science and Engineering, Nagoya University
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Affiliation(s)
- Hiroyasu IWAHARA
- Center for Integrated Research in Science and Engineering, Nagoya University
| | - Tetsuo SHIMURA
- Center for Integrated Research in Science and Engineering, Nagoya University
| | - Hiroshige MATSUMOTO
- Center for Integrated Research in Science and Engineering, Nagoya University
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