1
|
Gebhardt J, Elsässer C. DFT with corrections for an efficient and accurate description of strong electron correlations in NiO. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:205901. [PMID: 36863031 DOI: 10.1088/1361-648x/acc0be] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/02/2023] [Indexed: 06/18/2023]
Abstract
An efficient and accurate description of the electronic structure of a strongly correlated metal-oxide semiconductor like NiO has been notoriously difficult. Here, we study the capabilities and limitations of two frequently employed correction schemes, a DFT+Uon-site correction and a DFT+1/2 self-energy correction. While both methods individually are unable to provide satisfactory results, in combination they provide a very good description of all relevant physical quantities. Since both methods cope with different shortcomings of common density-functional theory (DFT) methods (using local-density or generalized-gradient approximations), their combination is not mutually dependent and remains broadly applicable. The combined approach retains the computational efficiency of DFT calculations while providing significantly improved predictive power.
Collapse
Affiliation(s)
- Julian Gebhardt
- Fraunhofer Institute for Mechanics of Materials IWM, Wöhlerstraße 11, 79108 Freiburg, Germany
- Cluster of Excellence livMatS at FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, Freiburg 79110, Germany
| | - Christian Elsässer
- Fraunhofer Institute for Mechanics of Materials IWM, Wöhlerstraße 11, 79108 Freiburg, Germany
- Cluster of Excellence livMatS at FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, Freiburg 79110, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Straße 21, Freiburg 79104, Germany
| |
Collapse
|
2
|
Bagus PS, Nelin CJ, Brundle CR, Crist BV, Ilton ES, Lahiri N, Rosso KM. Main and Satellite Features in the Ni 2p XPS of NiO. Inorg Chem 2022; 61:18077-18094. [DOI: 10.1021/acs.inorgchem.2c02549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Paul S. Bagus
- Department of Chemistry, University of North Texas, Denton, Texas 76203-5017, United States
| | | | | | | | - Eugene S. Ilton
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Nabajit Lahiri
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Kevin M. Rosso
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| |
Collapse
|
3
|
Higashi K, Yamaguchi T, Takahashi Y, Hariki A. Charge-transfer effect in Fe 2 pcore-level x-ray photoemission spectra of trivalent Fe oxides: LDA + DMFT study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:375602. [PMID: 35793685 DOI: 10.1088/1361-648x/ac7f18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
Motivated by recent hard x-ray photoemission spectroscopy (XPS) experiment for trivalent Fe oxides Sr2FeMoO6(ferrimagnetic correlated metal) and LaFeO3(antiferromagnetic Mott insulator) (Phuyalet al2021J. Phys. Chem.C12511249-56), we present a theoretical analysis of the Fe 2pcore-level spectra using a computational method based on local density approximation combined with dynamical mean-field theory. We find that a nonlocal screening (NLS) effect in the XPS final states is crucial for interpreting the experimental XPS result of both the Fe oxides. A close relationship between the NLS feature in core-level spectra and a long-range magnetic ordering is emphasized.
Collapse
Affiliation(s)
- Keisuke Higashi
- Department of Physics and Electronics, Graduate School of Engineering, Osaka Metropolitan University, 1-1 Gakuen-cho, Nakaku, Sakai, Osaka 599-8531, Japan
| | - Tatsuya Yamaguchi
- Department of Physics and Electronics, Graduate School of Engineering, Osaka Metropolitan University, 1-1 Gakuen-cho, Nakaku, Sakai, Osaka 599-8531, Japan
| | - Yoshihiro Takahashi
- Department of Physics and Electronics, Graduate School of Engineering, Osaka Metropolitan University, 1-1 Gakuen-cho, Nakaku, Sakai, Osaka 599-8531, Japan
| | - Atsushi Hariki
- Department of Physics and Electronics, Graduate School of Engineering, Osaka Metropolitan University, 1-1 Gakuen-cho, Nakaku, Sakai, Osaka 599-8531, Japan
| |
Collapse
|
4
|
Jin Y, Yan M, Kremer T, Voloshina E, Dedkov Y. Mott-Hubbard insulating state for the layered van der Waals [Formula: see text] (X: S, Se) as revealed by NEXAFS and resonant photoelectron spectroscopy. Sci Rep 2022; 12:735. [PMID: 35031642 PMCID: PMC8760309 DOI: 10.1038/s41598-021-04557-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 12/22/2021] [Indexed: 12/05/2022] Open
Abstract
A broad family of the nowadays studied low-dimensional systems, including 2D materials, demonstrate many fascinating properties, which however depend on the atomic composition as well as on the system dimensionality. Therefore, the studies of the electronic correlation effects in the new 2D materials is of paramount importance for the understanding of their transport, optical and catalytic properties. Here, by means of electron spectroscopy methods in combination with density functional theory calculations we investigate the electronic structure of a new layered van der Waals [Formula: see text] (X: S, Se) materials. Using systematic resonant photoelectron spectroscopy studies we observed strong resonant behavior for the peaks associated with the [Formula: see text] final state at low binding energies for these materials. Such observations clearly assign [Formula: see text] to the class of Mott-Hubbard type insulators for which the top of the valence band is formed by the hybrid Fe-S/Se electronic states. These observations are important for the deep understanding of this new class of materials and draw perspectives for their further applications in different application areas, like (opto)spintronics and catalysis.
Collapse
Affiliation(s)
- Yichen Jin
- Department of Physics, Shanghai University, 99 Shangda Road, Shanghai, 200444 People’s Republic of China
| | - Mouhui Yan
- Department of Physics, Shanghai University, 99 Shangda Road, Shanghai, 200444 People’s Republic of China
| | - Tomislav Kremer
- Institut für Chemie und Biochemie, Freie Universität Berlin, 14195 Berlin, Germany
| | - Elena Voloshina
- Department of Physics, Shanghai University, 99 Shangda Road, Shanghai, 200444 People’s Republic of China
- Institut für Chemie und Biochemie, Freie Universität Berlin, 14195 Berlin, Germany
- Centre of Excellence ENSEMBLE3 Sp. z o. o., Wolczynska Str. 133, 01-919 Warsaw, Poland
| | - Yuriy Dedkov
- Department of Physics, Shanghai University, 99 Shangda Road, Shanghai, 200444 People’s Republic of China
- Institut für Chemie und Biochemie, Freie Universität Berlin, 14195 Berlin, Germany
- Centre of Excellence ENSEMBLE3 Sp. z o. o., Wolczynska Str. 133, 01-919 Warsaw, Poland
| |
Collapse
|
5
|
Yan M, Jin Y, Wu Z, Tsaturyan A, Makarova A, Smirnov D, Voloshina E, Dedkov Y. Correlations in the Electronic Structure of van der Waals NiPS 3 Crystals: An X-ray Absorption and Resonant Photoelectron Spectroscopy Study. J Phys Chem Lett 2021; 12:2400-2405. [PMID: 33661001 DOI: 10.1021/acs.jpclett.1c00394] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The electronic structure of high-quality van der Waals NiPS3 crystals was studied using near-edge X-ray absorption spectroscopy (NEXAFS) and resonant photoelectron spectroscopy (ResPES) in combination with density functional theory (DFT) approach. The experimental spectroscopic methods, being element specific, allow one to discriminate between atomic contributions in the valence and conduction band density of states and give direct comparison with the results of DFT calculations. Analysis of the NEXAFS and ResPES data allows one to identify the NiPS3 material as a charge-transfer insulator. Obtained spectroscopic and theoretical data are very important for the consideration of possible correlated-electron phenomena in such transition-metal layered materials, where the interplay between different degrees of freedom for electrons defines their electronic properties, allowing one to understand their optical and transport properties and to propose further possible applications in electronics, spintronics, and catalysis.
Collapse
Affiliation(s)
- Mouhui Yan
- Department of Physics, Shanghai University, 200444 Shanghai, China
| | - Yichen Jin
- Department of Physics, Shanghai University, 200444 Shanghai, China
| | - Zhicheng Wu
- Department of Physics, Shanghai University, 200444 Shanghai, China
| | - Arshak Tsaturyan
- Institute of Physical and Organic Chemistry, Southern Federal University, 344090 Rostov on Don, Russia
| | - Anna Makarova
- Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| | - Dmitry Smirnov
- Institut für Festkörper-und Materialphysik, Technische Universität Dresden, 01069 Dresden, Germany
| | - Elena Voloshina
- Department of Physics, Shanghai University, 200444 Shanghai, China
- Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| | - Yuriy Dedkov
- Department of Physics, Shanghai University, 200444 Shanghai, China
- Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| |
Collapse
|
6
|
Bagus PS, Brundle C, Ilton ES. A rigorous non-empirical theoretical analysis of the 2p XPS of NiO: Is it necessary to invoke nonlocal screening? J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114135] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
7
|
Gillmeister K, Golež D, Chiang CT, Bittner N, Pavlyukh Y, Berakdar J, Werner P, Widdra W. Ultrafast coupled charge and spin dynamics in strongly correlated NiO. Nat Commun 2020; 11:4095. [PMID: 32796844 PMCID: PMC7429846 DOI: 10.1038/s41467-020-17925-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 07/17/2020] [Indexed: 11/30/2022] Open
Abstract
Charge excitations across an electronic band gap play an important role in opto-electronics and light harvesting. In contrast to conventional semiconductors, studies of above-band-gap photoexcitations in strongly correlated materials are still in their infancy. Here we reveal the ultrafast dynamics controlled by Hund’s physics in strongly correlated photoexcited NiO. By combining time-resolved two-photon photoemission experiments with state-of-the-art numerical calculations, an ultrafast (≲10 fs) relaxation due to Hund excitations and related photo-induced in-gap states are identified. Remarkably, the weight of these in-gap states displays long-lived coherent THz oscillations up to 2 ps at low temperature. The frequency of these oscillations corresponds to the strength of the antiferromagnetic superexchange interaction in NiO and their lifetime vanishes slightly above the Néel temperature. Numerical simulations of a two-band t-J model reveal that the THz oscillations originate from the interplay between local many-body excitations and antiferromagnetic spin correlations. Nickel Oxide (NiO) is a strongly correlated insulator with antiferromagnetic (AFM) ordering. Here, using pump-probe photoemission on NiO, the authors observe coherent terahertz oscillations in the photoemission signal, a signature of an in-gap state coupled to the AFM background.
Collapse
Affiliation(s)
- Konrad Gillmeister
- Institute of Physics, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle, Germany
| | - Denis Golež
- Center for Computational Quantum Physics, Flatiron Institute, 162 Fifth Avenue, New York, NY 10010, USA.,Department of Physics, University of Fribourg, 1700, Fribourg, Switzerland
| | - Cheng-Tien Chiang
- Institute of Physics, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle, Germany
| | - Nikolaj Bittner
- Department of Physics, University of Fribourg, 1700, Fribourg, Switzerland
| | - Yaroslav Pavlyukh
- Department of Physics, Technische Universität Kaiserslautern, 67653, Kaiserslautern, Germany
| | - Jamal Berakdar
- Institute of Physics, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle, Germany
| | - Philipp Werner
- Department of Physics, University of Fribourg, 1700, Fribourg, Switzerland.
| | - Wolf Widdra
- Institute of Physics, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle, Germany. .,Max Planck Institute of Microstructure Physics, 06120, Halle, Germany.
| |
Collapse
|
8
|
Woicik JC, Weiland C, Rumaiz AK, Brumbach MT, Ablett JM, Shirley EL, Kas JJ, Rehr JJ. Core hole processes in x-ray absorption and photoemission by resonant Auger-electron spectroscopy and first-principles theory. PHYSICAL REVIEW. B 2020; 101:10.1103/physrevb.101.245105. [PMID: 34409241 PMCID: PMC8370031 DOI: 10.1103/physrevb.101.245105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Electron-core hole interactions are critical for proper interpretation of core-level spectroscopies commonly used as analytical tools in materials science. Here we utilize resonant Auger-electron spectroscopy to uniquely identify exciton, shake, and charge-transfer processes that result from the sudden creation of the core hole in both x-ray-absorption and photoemission spectra. These effects are captured for the transition-metal compounds SrTiO3 and MoS2 by fully ab initio, combined real-time cumulant, and Bethe-Salpeter equation approaches to account for core hole dynamics and screening. Atomic charges and excited-state electron-density fluctuations reflect materials' solid-state electronic structure, loss of translational symmetry around the core hole, and breakdown of the sudden approximation. They also demonstrate competition between long- and short-range screening in a solid.
Collapse
Affiliation(s)
- J C Woicik
- Material Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - C Weiland
- Material Measurement Science Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - A K Rumaiz
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - M T Brumbach
- Materials Characterization Department, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J M Ablett
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, 91192 Gif-sur-Yvette Cedex, France
| | - E L Shirley
- Sensor Science Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - J J Kas
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - J J Rehr
- Department of Physics, University of Washington, Seattle, Washington 98195, USA
| |
Collapse
|
9
|
Chakrabarti S, Carolan D, Alessi B, Maguire P, Svrcek V, Mariotti D. Microplasma-synthesized ultra-small NiO nanocrystals, a ubiquitous hole transport material. NANOSCALE ADVANCES 2019; 1:4915-4925. [PMID: 36133136 PMCID: PMC9417055 DOI: 10.1039/c9na00299e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 10/21/2019] [Indexed: 05/27/2023]
Abstract
We report on a one-step hybrid atmospheric pressure plasma-liquid synthesis of ultra-small NiO nanocrystals (2 nm mean diameter), which exhibit strong quantum confinement. We show the versatility of the synthesis process and present the superior material characteristics of the nanocrystals (NCs). The band diagram of the NiO NCs, obtained experimentally, highlights ideal features for their implementation as a hole transport layer in a wide range of photovoltaic (PV) device architectures. As a proof of concept, we demonstrate the NiO NCs as a hole transport layer for three different PV device test architectures, which incorporate silicon quantum dots (Si-QDs), nitrogen-doped carbon quantum dots (N-CQDs) and perovskite as absorber layers. Our results clearly show ideal band alignment which could lead to improved carrier extraction into the metal contacts for all three solar cells. In addition, in the case of perovskite solar cells, the NiO NC hole transport layer acted as a protective layer preventing the degradation of halide perovskites from ambient moisture with a stable performance for >70 days. Our results also show unique characteristics that are highly suitable for future developments in all-inorganic 3rd generation solar cells (e.g. based on quantum dots) where quantum confinement can be used effectively to tune the band diagram to fit the energy level alignment requirements of different solar cell architectures.
Collapse
Affiliation(s)
- Supriya Chakrabarti
- Nanotechnology & Integrated Bio-Engineering Centre (NIBEC), Ulster University Jordanstown, Newtownabbey Co. Antrim BT37 0QB UK
- Centre for Carbon Materials, International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI) Balapur P.O. Hyderabad 500005 India
| | - Darragh Carolan
- Nanotechnology & Integrated Bio-Engineering Centre (NIBEC), Ulster University Jordanstown, Newtownabbey Co. Antrim BT37 0QB UK
| | - Bruno Alessi
- Nanotechnology & Integrated Bio-Engineering Centre (NIBEC), Ulster University Jordanstown, Newtownabbey Co. Antrim BT37 0QB UK
| | - Paul Maguire
- Nanotechnology & Integrated Bio-Engineering Centre (NIBEC), Ulster University Jordanstown, Newtownabbey Co. Antrim BT37 0QB UK
| | - Vladimir Svrcek
- National Institute of Advanced Industrial Science and Technology (AIST), Department of Energy and Environment, Research Center of Photovoltaics, Advanced Processing Team Central 2, Umezono 1-1-1 Tsukuba Ibaraki 305-8568 Japan
| | - Davide Mariotti
- Nanotechnology & Integrated Bio-Engineering Centre (NIBEC), Ulster University Jordanstown, Newtownabbey Co. Antrim BT37 0QB UK
| |
Collapse
|
10
|
Hashimoto Y, Taguchi M, Fukami S, Momono H, Matsushita T, Matsuda H, Matsui F, Daimon H. Site-sensitive X-ray photoelectron spectroscopy of Fe3
O4
by photoelectron diffraction. SURF INTERFACE ANAL 2018. [DOI: 10.1002/sia.6568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Yusuke Hashimoto
- Materials Science; Nara Institute of Science and Technology (NAIST); Nara Japan
| | - Munetaka Taguchi
- Materials Science; Nara Institute of Science and Technology (NAIST); Nara Japan
| | - Shun Fukami
- Materials Science; Nara Institute of Science and Technology (NAIST); Nara Japan
| | - Hiroki Momono
- Materials Science; Nara Institute of Science and Technology (NAIST); Nara Japan
| | - Tomohiro Matsushita
- Japan Synchrotron Radiation Research Institute (JASRI/SPring-8); Hyogo Japan
| | - Hiroyuki Matsuda
- Materials Science; Nara Institute of Science and Technology (NAIST); Nara Japan
| | - Fumihiko Matsui
- Materials Science; Nara Institute of Science and Technology (NAIST); Nara Japan
| | - Hiroshi Daimon
- Materials Science; Nara Institute of Science and Technology (NAIST); Nara Japan
| |
Collapse
|
11
|
Tong L, Wu W, Kuepper K, Scheurer A, Meyer K. Electrochemically Deposited Nickel Oxide from Molecular Complexes for Efficient Water Oxidation Catalysis. CHEMSUSCHEM 2018; 11:2752-2757. [PMID: 29883067 DOI: 10.1002/cssc.201800971] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Indexed: 06/08/2023]
Abstract
A facile method for the electrodeposition of amorphous nickel oxyhydroxide is described and discussed in which well-defined nickel complexes with pyridinedimethanol ligands are employed as single-source molecular precursors. No buffering agent is required to assist the anodic deposition process. The deposited nickel oxyhydroxide shows high robustness and efficiency for electrocatalytic water oxidation.
Collapse
Affiliation(s)
- Lianpeng Tong
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058, Erlangen, Germany
| | - Wenling Wu
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058, Erlangen, Germany
| | - Karsten Kuepper
- Department of Physics, University of Osnabrück, Barbarastraße 7, 49069, Osnabrück, Germany
| | - Andreas Scheurer
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058, Erlangen, Germany
| | - Karsten Meyer
- Department of Chemistry and Pharmacy, Inorganic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Egerlandstraße 1, 91058, Erlangen, Germany
| |
Collapse
|
12
|
Pincelli T, Lollobrigida V, Borgatti F, Regoutz A, Gobaut B, Schlueter C, Lee TL, Payne DJ, Oura M, Tamasaku K, Petrov AY, Graziosi P, Granozio FM, Cavallini M, Vinai G, Ciprian R, Back CH, Rossi G, Taguchi M, Daimon H, van der Laan G, Panaccione G. Quantifying the critical thickness of electron hybridization in spintronics materials. Nat Commun 2017; 8:16051. [PMID: 28714466 PMCID: PMC5520016 DOI: 10.1038/ncomms16051] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 05/15/2017] [Indexed: 11/09/2022] Open
Abstract
In the rapidly growing field of spintronics, simultaneous control of electronic and magnetic properties is essential, and the perspective of building novel phases is directly linked to the control of tuning parameters, for example, thickness and doping. Looking at the relevant effects in interface-driven spintronics, the reduced symmetry at a surface and interface corresponds to a severe modification of the overlap of electron orbitals, that is, to a change of electron hybridization. Here we report a chemically and magnetically sensitive depth-dependent analysis of two paradigmatic systems, namely La1−xSrxMnO3 and (Ga,Mn)As. Supported by cluster calculations, we find a crossover between surface and bulk in the electron hybridization/correlation and we identify a spectroscopic fingerprint of bulk metallic character and ferromagnetism versus depth. The critical thickness and the gradient of hybridization are measured, setting an intrinsic limit of 3 and 10 unit cells from the surface, respectively, for (Ga,Mn)As and La1−xSrxMnO3, for fully restoring bulk properties. Surface versus bulk effects in electronic structure of spintronics materials are crucial to their applications but are yet well understood. Here the authors experimentally determine the critical thickness that defines the crossover of electron hybridization between surface and bulk for two prototype spintronics materials.
Collapse
Affiliation(s)
- T Pincelli
- Istituto Officina dei Materiali-CNR, Laboratorio TASC, Area Science Park, S.S. 14, Km 163.5, Trieste I-34149, Italy.,Dipartimento di Fisica, Università di Milano, Via Celoria 16, Milano I-20133, Italy
| | - V Lollobrigida
- Istituto Officina dei Materiali-CNR, Laboratorio TASC, Area Science Park, S.S. 14, Km 163.5, Trieste I-34149, Italy.,Dipartimento di Scienze, Università degli Studi Roma Tre, Via della Vasca Navale 84, Roma I-00146, Italy
| | - F Borgatti
- Consiglio Nazionale delle Ricerche-Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), via P. Gobetti 101, Bologna I-40129, Italy
| | - A Regoutz
- Department of Materials, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - B Gobaut
- Sincrotrone Trieste S.C.p.A., S.S. 14 Km 163.5, Area Science Park, Trieste 34149, Italy
| | - C Schlueter
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - T-L Lee
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - D J Payne
- Department of Materials, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - M Oura
- RIKEN SPring-8 Center, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - K Tamasaku
- RIKEN SPring-8 Center, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - A Y Petrov
- Istituto Officina dei Materiali-CNR, Laboratorio TASC, Area Science Park, S.S. 14, Km 163.5, Trieste I-34149, Italy
| | - P Graziosi
- Consiglio Nazionale delle Ricerche-Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), via P. Gobetti 101, Bologna I-40129, Italy
| | - F Miletto Granozio
- CNR-SPIN, Complesso Universitario Monte S. Angelo, Napoli 80126, Italy.,Dipartimento di Fisica, Università 'Federico II' di Napoli, Napoli, 80126, Italy
| | - M Cavallini
- Consiglio Nazionale delle Ricerche-Istituto per lo Studio dei Materiali Nanostrutturati (CNR-ISMN), via P. Gobetti 101, Bologna I-40129, Italy
| | - G Vinai
- Istituto Officina dei Materiali-CNR, Laboratorio TASC, Area Science Park, S.S. 14, Km 163.5, Trieste I-34149, Italy
| | - R Ciprian
- Istituto Officina dei Materiali-CNR, Laboratorio TASC, Area Science Park, S.S. 14, Km 163.5, Trieste I-34149, Italy
| | - C H Back
- Institut fur Experimentelle Physik, Universitat Regensburg, Regensburg D-93040, Germany
| | - G Rossi
- Istituto Officina dei Materiali-CNR, Laboratorio TASC, Area Science Park, S.S. 14, Km 163.5, Trieste I-34149, Italy.,Dipartimento di Fisica, Università di Milano, Via Celoria 16, Milano I-20133, Italy
| | - M Taguchi
- RIKEN SPring-8 Center, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.,Nara Institute of Science and Technology, 8-9165 Takayama, Ikoma, Nara 630-0192, Japan
| | - H Daimon
- Nara Institute of Science and Technology, 8-9165 Takayama, Ikoma, Nara 630-0192, Japan
| | - G van der Laan
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - G Panaccione
- Istituto Officina dei Materiali-CNR, Laboratorio TASC, Area Science Park, S.S. 14, Km 163.5, Trieste I-34149, Italy
| |
Collapse
|
13
|
Wang M, Song X, Dai S, Xu W, Yang Q, Liu J, Hu C, Wei D. NiO nanoparticles supported on graphene 3D network current collector for high-performance electrochemical energy storage. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.08.036] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
14
|
Taguchi M, Chainani A, Ueda S, Matsunami M, Ishida Y, Eguchi R, Tsuda S, Takata Y, Yabashi M, Tamasaku K, Nishino Y, Ishikawa T, Daimon H, Todo S, Tanaka H, Oura M, Senba Y, Ohashi H, Shin S. Temperature Dependence of Magnetically Active Charge Excitations in Magnetite across the Verwey Transition. PHYSICAL REVIEW LETTERS 2015; 115:256405. [PMID: 26722935 DOI: 10.1103/physrevlett.115.256405] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Indexed: 05/12/2023]
Abstract
We study the electronic structure of bulk single crystals and epitaxial films of Fe_{3}O_{4}. Fe 2p core level spectra show clear differences between hard x-ray (HAX) and soft x-ray photoemission spectroscopy (PES). The bulk-sensitive spectra exhibit temperature (T) dependence across the Verwey transition, which is missing in the surface-sensitive spectra. By using an extended impurity Anderson full-multiplet model-and in contrast to an earlier peak assignment-we show that the two distinct Fe species (A and B site) and the charge modulation at the B site are responsible for the newly found double peaks in the main peak above T_{V} and its T-dependent evolution. The Fe 2p HAXPES spectra show a clear magnetic circular dichroism (MCD) in the metallic phase of magnetized 100-nm-thick films. The model calculations also reproduce the MCD and identify the contributions from magnetically distinct A and B sites. Valence band HAXPES shows a finite density of states at E_{F} for the polaronic half metal with a remnant order above T_{V} and a clear gap formation below T_{V}. The results indicate that the Verwey transition is driven by changes in the strongly correlated and magnetically active B-site electronic states, consistent with resistivity and optical spectra.
Collapse
Affiliation(s)
- M Taguchi
- Material Science, Nara Institute of Science and Technology (NAIST), Ikoma, Nara 630-0192, Japan
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - A Chainani
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - S Ueda
- National Institute for Materials Science (NIMS), SPring-8, Sayo, Hyogo 679-5148, Japan
| | - M Matsunami
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Y Ishida
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - R Eguchi
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - S Tsuda
- National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0003, Japan
| | - Y Takata
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - M Yabashi
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - K Tamasaku
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - Y Nishino
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - T Ishikawa
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - H Daimon
- Material Science, Nara Institute of Science and Technology (NAIST), Ikoma, Nara 630-0192, Japan
| | - S Todo
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - H Tanaka
- ISIR-Sanken, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - M Oura
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - Y Senba
- JASRI/SPring-8, Sayo, Sayo, Hyogo 679-5198, Japan
| | - H Ohashi
- JASRI/SPring-8, Sayo, Sayo, Hyogo 679-5198, Japan
| | - S Shin
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| |
Collapse
|
15
|
Scheurer A, Korzekwa J, Nakajima T, Hampel F, Buling A, Derks C, Neumann M, Joly L, Petukhov K, Gieb K, Müller P, Kuepper K, Meyer K. Synthesis, Magnetic Properties, and X-ray Spectroscopy of Divalent Cobalt(II) and Nickel(II) Cubanes [MII4(HL2)4(OAc)4]. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201402988] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
16
|
Li G, Li L, Jiang D, Shi J. Design of a meso-structured Pd/NiO catalyst for highly efficient low temperature CO oxidation under ambient conditions. RSC Adv 2015. [DOI: 10.1039/c5ra05591a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A meso-structured Pd/NiO catalyst, fabricated through a controlled pyrolysis and in situ reduction protocol, showed much higher catalytic activity and stability for CO oxidation under ambient conditions.
Collapse
Affiliation(s)
- Gengnan Li
- Key Laboratory for Ultrafine Materials of Ministry of Education
- School of Materials Science and Engineering
- East China University of Science and Technology
- Shanghai
- China
| | - Liang Li
- Key Laboratory for Ultrafine Materials of Ministry of Education
- School of Materials Science and Engineering
- East China University of Science and Technology
- Shanghai
- China
| | - Dong Jiang
- Research Center of Analysis and Test
- East China University of Science and Technology
- Shanghai
- China
| | - Jianlin Shi
- Key Laboratory for Ultrafine Materials of Ministry of Education
- School of Materials Science and Engineering
- East China University of Science and Technology
- Shanghai
- China
| |
Collapse
|
17
|
Kumara LSR, Sakata O, Yang A, Yamauchi R, Taguchi M, Matsuda A, Yoshimoto M. Hard X-ray photoelectron spectroscopy of LixNi1-xO epitaxial thin films with a high lithium content. J Chem Phys 2014; 141:044718. [PMID: 25084948 DOI: 10.1063/1.4891366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The core-level and valence-band electronic structures of LixNi1-xO epitaxial thin films with x = 0, 0.27, and 0.48 were studied by hard X-ray photoelectron spectroscopy. A double peak structure, consisting of a main peak and a shoulder peak, and a satellite structure were observed in the Ni 2p3/2 core-level spectra. The intensity ratio of the shoulder to main peak in this double peak structure increased with increasing lithium content in LixNi1-xO. This lithium doping dependence of the Ni 2p3/2 core-level spectra was investigated using an extended cluster model, which included the Zhang-Rice (ZR) doublet bound states arising from a competition between O 2p - Ni 3d hybridization and the Ni on-site Coulomb interaction. The results indicated that the change in the intensity ratio in the main peak is because of a reduction in the ZR doublet bound states from lithium substitutions. This strongly suggests that holes compensating Li doping in LixNi1-xO are of primarily ZR character.
Collapse
Affiliation(s)
- L S R Kumara
- Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS), 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Osami Sakata
- Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS), 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Anli Yang
- Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS), 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Ryosuke Yamauchi
- Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259-J3-16, Nagatsuta, Midori, Yokohama 226-8502, Japan
| | - Munetaka Taguchi
- Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), Ikoma, Nara 630-0192, Japan
| | - Akifumi Matsuda
- Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259-J3-16, Nagatsuta, Midori, Yokohama 226-8502, Japan
| | - Mamoru Yoshimoto
- Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259-J3-16, Nagatsuta, Midori, Yokohama 226-8502, Japan
| |
Collapse
|
18
|
Visible light-induced reduction of carbon dioxide sensitized by a porphyrin–rhenium dyad metal complex on p-type semiconducting NiO as the reduction terminal end of an artificial photosynthetic system. J Catal 2014. [DOI: 10.1016/j.jcat.2013.03.025] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
19
|
Investigation of surface and non-local screening effects in the Ni 2p core level photoemission spectra of NiO. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2010.11.050] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
20
|
Taguchi M, Chainani A, Matsunami M, Eguchi R, Takata Y, Yabashi M, Tamasaku K, Nishino Y, Ishikawa T, Tsuda S, Watanabe S, Chen CT, Senba Y, Ohashi H, Fujiwara K, Nakamura Y, Takagi H, Shin S. Anomalous state sandwiched between Fermi liquid and charge ordered Mott-insulating phases of Ti4O7. PHYSICAL REVIEW LETTERS 2010; 104:106401. [PMID: 20366439 DOI: 10.1103/physrevlett.104.106401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Indexed: 05/29/2023]
Abstract
The Magnéli phase Ti(4)O(7) exhibits two sharp jumps in resistivity with coupled structural transitions as a function of temperature at T(c1) approximately 142 K and T(c2) = 154 K. We have studied electronic structure changes across the two transitions using 7 eV laser, soft x-ray, and hard x-ray (HX) photoemission spectroscopy (PES). Ti 2p-3d resonant PES and HX PES show a clear metallic Fermi edge and mixed valency above T(c2). The low temperature phase below T(c1) shows a clear insulating gap of approximately 100 meV. The intermediate phase between T(c1) and T(c2) indicates a pseudogap coexisting with remnant coherent states. HX PES and complementary calculations have confirmed the coherent screening in the strongly correlated intermediate phase. The results suggest the existence of a highly anomalous state sandwiched between the mixed-valent Fermi liquid and charge ordered Mott-insulating phase in Ti(4)O(7).
Collapse
Affiliation(s)
- M Taguchi
- Soft X-ray Spectroscopy Lab, RIKEN SPring-8 Center, Sayo, Sayo, Hyogo 679-5148, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Bagus P, Nelin C, Ilton E, Baron M, Abbott H, Primorac E, Kuhlenbeck H, Shaikhutdinov S, Freund HJ. The complex core level spectra of CeO2: An analysis in terms of atomic and charge transfer effects. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.01.041] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|