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Pfaff S, Larsson A, Orlov D, Rämisch L, Gericke SM, Lundgren E, Zetterberg J. A Polycrystalline Pd Surface Studied by Two-Dimensional Surface Optical Reflectance during CO Oxidation: Bridging the Materials Gap. ACS APPLIED MATERIALS & INTERFACES 2024; 16:444-453. [PMID: 38109219 PMCID: PMC10788831 DOI: 10.1021/acsami.3c11341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/19/2023] [Accepted: 11/13/2023] [Indexed: 12/20/2023]
Abstract
Industrial catalysts are complex materials systems operating in harsh environments. The active parts of the catalysts are nanoparticles that expose different facets with different surface orientations at which the catalytic reactions occur. However, these facets are close to impossible to study in detail under industrially relevant operating conditions. Instead, simpler model systems, such as single crystals with a well-defined surface orientation, have been successfully used to study gas-surface interactions such as adsorption and desorption, surface oxidation, and oxidation/reduction reactions. To more closely mimic the many facets exhibited by nanoparticles and thereby close the so-called materials gap, there has also been a recent move toward using polycrystalline surfaces and curved crystals. However, these studies are limited either by the pressure or spatial resolution at realistic pressures or by the number of surfaces studied simultaneously. In this work, we demonstrate the use of reflectance microscopy to study a vast number of catalytically active surfaces simultaneously under realistic and identical reaction conditions. As a proof of concept, we have conducted an operando experiment to study CO oxidation over a Pd polycrystal, where the polycrystalline surface acts as a collection of many single-crystal surfaces. Finally, we visualized the resulting data by plotting the reflectivity as a function of surface orientation. We think the techniques and visualization methods introduced in this work will be key toward bridging the materials gap in catalysis.
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Affiliation(s)
- Sebastian Pfaff
- Combustion
Research Facility, Sandia National Laboratories, 7011 East Ave, Livermore, California 94550, United States
| | - Alfred Larsson
- Division
of Synchrotron Radiation Research, Lund
University, Sölvegatan 14, S-22363 Lund, Sweden
| | - Dmytro Orlov
- Division
of Mechanics, Materials and Component Design, Lund University, Ole
Römers väg 1, S-22363 Lund, Sweden
| | - Lisa Rämisch
- Combustion
Physics, Lund University, Sölvegatan 14, S-22363 Lund, Sweden
| | - Sabrina M. Gericke
- Combustion
Physics, Lund University, Sölvegatan 14, S-22363 Lund, Sweden
| | - Edvin Lundgren
- Division
of Synchrotron Radiation Research, Lund
University, Sölvegatan 14, S-22363 Lund, Sweden
| | - Johan Zetterberg
- Combustion
Physics, Lund University, Sölvegatan 14, S-22363 Lund, Sweden
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2
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Teja YN, Sakar M. Comprehensive Insights into the Family of Atomically Thin 2D-Materials for Diverse Photocatalytic Applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2303980. [PMID: 37461252 DOI: 10.1002/smll.202303980] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 07/05/2023] [Indexed: 11/16/2023]
Abstract
2D materials with their fascinating physiochemical, structural, and electronic properties have attracted researchers and have been used for a variety of applications such as electrocatalysis, photocatalysis, energy storage, magnetoresistance, and sensing. In recent times, 2D materials have gained great momentum in the spectrum of photocatalytic applications such as pollutant degradation, water splitting, CO2 reduction, NH3 production, microbial disinfection, and heavy metal reduction, thanks to their superior properties including visible light responsive band gap, improved charge separation and electron mobility, suppressed charge recombination and high surface reactive sites, and thus enhance the photocatalytic properties rationally as compared to 3D and other low-dimensional materials. In this context, this review spot-lights the family of various 2D materials, their properties and their 2D structure-induced photocatalytic mechanisms while giving an overview on their synthesis methods along with a detailed discussion on their diverse photocatalytic applications. Furthermore, the challenges and the future opportunities are also presented related to the future developments and advancements of 2D materials for the large-scale real-time photocatalytic applications.
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Affiliation(s)
- Y N Teja
- Centre for Nano and Material Sciences, Jain (Deemed to be) University, Jain Global Campus, Kanakapura, Bangalore, Karnataka, 562112, India
| | - Mohan Sakar
- Centre for Nano and Material Sciences, Jain (Deemed to be) University, Jain Global Campus, Kanakapura, Bangalore, Karnataka, 562112, India
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3
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Li Z, Haynes BS, Montoya A. Carbon Monoxide Oxidation on Ceria-Supported Nanoclusters. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37883665 DOI: 10.1021/acsami.3c09468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Periodic density functional theory is used to evaluate the minimum energy pathways of CO oxidation on cerium oxide-supported platinum and palladium nanoclusters (Pt/CeO2 and Pd/CeO2). For Pt/CeO2, the oxidation process involves the participation of lattice oxygen from CeO2 at the boundary sites of the cluster-ceria interface, which exhibits an exceptionally low energy barrier. Conversely, on Pd/CeO2, oxidation predominantly occurs through oxygen species bound to the Pd cluster. Experimental analysis using the temperature-programmed reduction of the oxidized Pd/CeO2 catalyst reveals a lower CO oxidation temperature compared to Pt/CeO2. This observation aligns with the anticipated decrease in the energy barrier for CO oxidation due to the oxygen coverage of the Pd cluster.
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Affiliation(s)
- Zuo Li
- Faculty of Engineering, School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Brian S Haynes
- Faculty of Engineering, School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Alejandro Montoya
- Faculty of Engineering, School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
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4
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Roger M, Artiglia L, Boucly A, Buttignol F, Agote-Arán M, van Bokhoven JA, Kröcher O, Ferri D. Improving time-resolution and sensitivity of in situ X-ray photoelectron spectroscopy of a powder catalyst by modulated excitation. Chem Sci 2023; 14:7482-7491. [PMID: 37449079 PMCID: PMC10337771 DOI: 10.1039/d3sc01274c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/29/2023] [Indexed: 07/18/2023] Open
Abstract
Ambient pressure X-ray photoelectron spectroscopy (APXPS) is a powerful tool to characterize the surface structure of heterogeneous catalysts in situ. In order to improve the time resolution and the signal-to-noise (S/N) ratio of photoemission spectra, we collected consecutive APXP spectra during the periodic perturbation of a powder Pd/Al2O3 catalyst away from its equilibrium state according to the modulated excitation approach (ME). Averaging of the spectra along the alternate pulses of O2 and CO improved the S/N ratio demonstrating that the time resolution of the measurement can be limited solely to the acquisition time of one spectrum. Through phase sensitive analysis of the averaged time-resolved spectra, the formation/consumption dynamics of three oxidic species, two metal species, adsorbed CO on Pd0 as well as Pdn+ (n > 2) was followed along the gas switches. Pdn+ and 2-fold surface PdO species were recognised as most reactive to the gas switches. Our approach demonstrates that phase sensitive detection of time-resolved XPS data allows following the dynamics of reactive species at the solid-gas interface under different reaction environments with unprecedented precision.
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Affiliation(s)
- M Roger
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
- École Polytechnique Fédérale de Lausanne (EPFL), Institute for Chemical Sciences and Engineering CH-1015 Lausanne Switzerland
| | - L Artiglia
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
| | - A Boucly
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
| | - F Buttignol
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
- École Polytechnique Fédérale de Lausanne (EPFL), Institute for Chemical Sciences and Engineering CH-1015 Lausanne Switzerland
| | - M Agote-Arán
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
| | - J A van Bokhoven
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zurich 8093 Zurich Switzerland
| | - O Kröcher
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
- École Polytechnique Fédérale de Lausanne (EPFL), Institute for Chemical Sciences and Engineering CH-1015 Lausanne Switzerland
| | - D Ferri
- Paul Scherrer Institut Forschungsstrasse 111, CH-5232 Villigen PSI Switzerland
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5
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Springborg M, Zhou M, Kirtman B. The shape effect and its consequences for polar surfaces and for heterogeneous catalysis. Phys Chem Chem Phys 2023; 25:13308-13319. [PMID: 37133928 DOI: 10.1039/d3cp00996c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In this paper we develop the shape effect, which is relevant for crystalline materials whose size is larger than that of the thermodynamic limit. According to this effect the electronic properties of one surface of a crystal depend upon all of its surfaces, i.e. on the overall shape. At first, qualitative mathematical arguments are presented for the existence of this effect based on the conditions for the stability of polar surfaces. Our treatment explains why such surfaces are observed even though earlier theory indicated that they should not exist. Then, models are developed from which it is found computationally that changing the shape of a polar crystal can substantially alter the magnitude of its surface charges. Apart from surface charges, it follows that the crystal shape will also significantly affect bulk properties, most notably polarization and piezoelectric responses. Additional model calculations show a strong shape effect on the activation energy for heterogeneous catalysis primarily through local surface charges rather than a non-local/long range electrostatic potential.
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Affiliation(s)
- Michael Springborg
- Laboratory of Theoretical Chemistry, Department of Chemistry, Namur Institute of Structured Matter (NISM), University of Namur, Rue de Bruxelles 61, 5000 Namur, Belgium.
| | - Meijuan Zhou
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, P. R. China.
| | - Bernard Kirtman
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA.
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6
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Svenum IH, Strømsheim MD, Knudsen J, Venvik HJ. Activity and segregation behavior of Pd75%Ag25%(111) during CO oxidation– an in situ NAP-XPS investigation. J Catal 2022. [DOI: 10.1016/j.jcat.2022.11.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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7
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Gun Oh D, Aleksandrov HA, Kim H, Koleva IZ, Khivantsev K, Vayssilov GN, Hun Kwak J. Key Role of a‐Top CO on Terrace Sites of Metallic Pd Clusters for CO Oxidation. Chemistry 2022; 28:e202200684. [DOI: 10.1002/chem.202200684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Dong Gun Oh
- School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) 50 UNIST-gil Ulsan 44919 Republic of Korea
| | | | - Haneul Kim
- School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) 50 UNIST-gil Ulsan 44919 Republic of Korea
| | - Iskra Z. Koleva
- Faculty of Chemistry and Pharmacy University of Sofia 1126 Sofia Bulgaria
| | - Konstantin Khivantsev
- Institute for Integrated Catalysis Pacific Northwest National Laboratory Richland Washington 99352 USA
| | | | - Ja Hun Kwak
- School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) 50 UNIST-gil Ulsan 44919 Republic of Korea
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8
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Charge transport variation from Bloch-Grüneisen to Mott variable range hopping and transport change due to hydrogenation in Palladium thin films. Sci Rep 2021; 11:22298. [PMID: 34785715 PMCID: PMC8595451 DOI: 10.1038/s41598-021-01787-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/26/2021] [Indexed: 11/17/2022] Open
Abstract
We report a systematic investigation of the differences in charge transport mechanism in ultra-thin nano-island like films of palladium with thickness varying between 5 nm and 3 nm. The thicker films were found to be metallic in a large temperature range with a dominant Bloch-Grüneisen mechanism of charge transport arising due to electron-acoustic phonon scattering. These films were also found to exhibit an additional electron-magnon scattering. At temperatures below 20 K, the two films displayed a metal-insulator transition which was explained using Al'tshuler's model of increased scattering in disordered conductors. The thinner films were insulating and were found to exhibit Mott's variable range hopping mechanism of charge transport. The thinnest film showed a linear decrease of resistance with an increase in temperature in the entire temperature range. The island-like thin films were found to display very different response to hydrogenation at room temperature where the metallic films were found to display a decrease of resistance while the insulating films were found to have an increase of resistance. The decrease of resistance was ascribed to a hydrogen induced lattice expansion in the thin films that were at the percolation threshold while the resistance increase to an increase in work function of the films due to an increased adsorption of the hydrogen atoms at the surface sites of palladium.
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9
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Egle T, O'Connor CR, Friend CM. Regeneration of Active Surface Alloys during Cyclic Oxidation and Reduction: Oxidation of H 2 on Pd/Ag(111). J Phys Chem Lett 2021; 12:6752-6759. [PMID: 34264673 DOI: 10.1021/acs.jpclett.1c01367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The surface morphology and composition of a catalyst during excursions between oxidizing and reducing conditions can change substantially, especially in bimetallic alloys. Both thermodynamic and kinetic factors play a role in determining the properties of alloy surfaces where the active phase may be a metastable state. Previously, Ag oxide reduction was shown to be dramatically enhanced when Pd is on the surface; however, Pd is more stable when dissolved in Ag, raising the question as to whether a highly active Pd surface state will persist over multiple reaction cycles, a requirement for catalytic function. Experiments herein demonstrate that the enhanced chemical functionality due to the presence of Pd on the surface is retained, based on the enhanced rate of silver oxide reduction over multiple oxidation/reduction cycles for a Pd/Ag(111) model. Repeated oxidation and reduction promote PdAg alloying, and reversible structural and compositional changes are detected using X-ray photoelectron spectroscopy. This study establishes that metastable phases can persist in reactive processes on surfaces, indicating their potential in heterogeneous catalysis.
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10
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Hartwig C, Schweinar K, Nicholls R, Beeg S, Schlögl R, Greiner M. Surface composition of AgPd single-atom alloy catalyst in an oxidative environment. J Chem Phys 2021; 154:174708. [PMID: 34241061 DOI: 10.1063/5.0045999] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Single-atom alloys (SAAs) have recently gained considerable attention in the field of heterogeneous catalysis research due to their potential for novel catalytic properties. While SAAs are often examined in reactions of reductive atmospheres, such as hydrogenation reactions, in the present work, we change the focus to AgPd SAAs in oxidative environments since Pd has the highest catalytic activity of all metals for oxidative reactions. Here, we examine how the chemical reactivity of AgPd SAAs differs from its constituent Pd in an oxidative atmosphere. For this purpose, electronic structure changes in an Ag0.98Pd0.02 SAA foil in 1 mbar of O2 were studied by in situ x-ray photoemission spectroscopy and compared with the electronic structure of a Pd foil under the same conditions. When heated in an oxidative atmosphere, Pd in Ag0.98Pd0.02 partly oxidizes and forms a metastable PdOx surface oxide. By using a peak area modeling procedure, we conclude that PdOx on Ag0.98Pd0.02 is present as thin, possibly monolayer thick, PdOx islands on the surface. In comparison to the PdO formed on the Pd foil, the PdOx formed on AgPd is substantially less thermodynamically stable, decomposing at temperatures about 270 °C lower than the native oxide on Pd. Such behavior is an interesting property of oxides formed on dilute alloys, which could be potentially utilized in catalytic oxidative reactions such as methane oxidation.
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Affiliation(s)
- Caroline Hartwig
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
| | - Kevin Schweinar
- Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany
| | - Rachel Nicholls
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
| | - Sebastian Beeg
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
| | - Robert Schlögl
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
| | - Mark Greiner
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
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11
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Chen L, Medlin JW, Grönbeck H. On the Reaction Mechanism of Direct H2O2 Formation over Pd Catalysts. ACS Catal 2021. [DOI: 10.1021/acscatal.0c05548] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lin Chen
- Department of Physics and Competence Centre for Catalysis, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - J. Will Medlin
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, 80303 Colorado, United States
| | - Henrik Grönbeck
- Department of Physics and Competence Centre for Catalysis, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
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12
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How the anisotropy of surface oxide formation influences the transient activity of a surface reaction. Nat Commun 2021; 12:69. [PMID: 33398022 PMCID: PMC7782819 DOI: 10.1038/s41467-020-20377-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/30/2020] [Indexed: 11/30/2022] Open
Abstract
Scanning photoelectron microscopy (SPEM) and photoemission electron microscopy (PEEM) allow local surface analysis and visualising ongoing reactions on a µm-scale. These two spatio-temporal imaging methods are applied to polycrystalline Rh, representing a library of well-defined high-Miller-index surface structures. The combination of these techniques enables revealing the anisotropy of surface oxidation, as well as its effect on catalytic hydrogen oxidation. In the present work we observe, using locally-resolved SPEM, structure-sensitive surface oxide formation, which is summarised in an oxidation map and quantitatively explained by the novel step density (SDP) and step edge (SEP) parameters. In situ PEEM imaging of ongoing H2 oxidation allows a direct comparison of the local reactivity of metallic and oxidised Rh surfaces for the very same different stepped surface structures, demonstrating the effect of Rh surface oxides. Employing the velocity of propagating reaction fronts as indicator of surface reactivity, we observe a high transient activity of Rh surface oxide in H2 oxidation. The corresponding velocity map reveals the structure-dependence of such activity, representing a direct imaging of a structure-activity relation for plenty of well-defined surface structures within one sample. Surface oxide formation under reaction conditions may change the catalytic activity of a catalyst. Here, the authors explore the effect of atomic structure of Rh surfaces on the surface oxide formation and its influence on catalytic activity in hydrogen oxidation, revealing a high transient activity.
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13
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Timmermann J, Kraushofer F, Resch N, Li P, Wang Y, Mao Z, Riva M, Lee Y, Staacke C, Schmid M, Scheurer C, Parkinson GS, Diebold U, Reuter K. IrO_{2} Surface Complexions Identified through Machine Learning and Surface Investigations. PHYSICAL REVIEW LETTERS 2020; 125:206101. [PMID: 33258623 DOI: 10.1103/physrevlett.125.206101] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 09/22/2020] [Indexed: 06/12/2023]
Abstract
A Gaussian approximation potential was trained using density-functional theory data to enable a global geometry optimization of low-index rutile IrO_{2} facets through simulated annealing. Ab initio thermodynamics identifies (101) and (111) (1×1) terminations competitive with (110) in reducing environments. Experiments on single crystals find that (101) facets dominate and exhibit the theoretically predicted (1×1) periodicity and x-ray photoelectron spectroscopy core-level shifts. The obtained structures are analogous to the complexions discussed in the context of ceramic battery materials.
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Affiliation(s)
- Jakob Timmermann
- Chair for Theoretical Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstrasse 4, D-85747 Garching, Germany
| | - Florian Kraushofer
- Institute of Applied Physics, Technical University of Vienna, Wiedner Hauptstrasse 8-10/134, A-1040 Vienna, Austria
| | - Nikolaus Resch
- Institute of Applied Physics, Technical University of Vienna, Wiedner Hauptstrasse 8-10/134, A-1040 Vienna, Austria
| | - Peigang Li
- Department of Physics and Engineering Physics, Tulane University, New Orleans, Louisiana 70118, USA
| | - Yu Wang
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Zhiqiang Mao
- Department of Physics and Engineering Physics, Tulane University, New Orleans, Louisiana 70118, USA
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Michele Riva
- Institute of Applied Physics, Technical University of Vienna, Wiedner Hauptstrasse 8-10/134, A-1040 Vienna, Austria
| | - Yonghyuk Lee
- Chair for Theoretical Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstrasse 4, D-85747 Garching, Germany
| | - Carsten Staacke
- Chair for Theoretical Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstrasse 4, D-85747 Garching, Germany
| | - Michael Schmid
- Institute of Applied Physics, Technical University of Vienna, Wiedner Hauptstrasse 8-10/134, A-1040 Vienna, Austria
| | - Christoph Scheurer
- Chair for Theoretical Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstrasse 4, D-85747 Garching, Germany
| | - Gareth S Parkinson
- Institute of Applied Physics, Technical University of Vienna, Wiedner Hauptstrasse 8-10/134, A-1040 Vienna, Austria
| | - Ulrike Diebold
- Institute of Applied Physics, Technical University of Vienna, Wiedner Hauptstrasse 8-10/134, A-1040 Vienna, Austria
| | - Karsten Reuter
- Chair for Theoretical Chemistry and Catalysis Research Center, Technical University of Munich, Lichtenbergstrasse 4, D-85747 Garching, Germany
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
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14
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Toyoshima R, Amemiya K, Mase K, Kondoh H. Orientation-Dependent Hindrance to the Oxidation of Pd-Au Alloy Surfaces. J Phys Chem Lett 2020; 11:9249-9254. [PMID: 33073999 DOI: 10.1021/acs.jpclett.0c02645] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Oxidation of monometallic Pd and bimetallic Pd3Au alloy surfaces are observed by in situ ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) at an elevated pressure (100 mTorr O2 ambient). It is directly evidenced that the alloying with Au hinders the surface oxidation of Pd3Au surfaces compared with monometallic Pd surfaces. Remarkably, the oxidation behavior is clearly different between Pd3Au(111) and (100) surfaces. The (100) surface has a relatively Pd-rich surface composition, and the surface oxide layer is formed, whereas the (111) surface has a Au-rich composition, and the surface oxidation is quite limited. A combined approach of experimental and theoretical techniques reveals that Pd/Au surface composition and atomic arrangement are key factors determining the oxidation behavior.
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Affiliation(s)
- Ryo Toyoshima
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Kenta Amemiya
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Tsukuba, Ibaraki 305-0801, Japan
| | - Kazuhiko Mase
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Tsukuba, Ibaraki 305-0801, Japan
| | - Hiroshi Kondoh
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
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15
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Held G, Venturini F, Grinter DC, Ferrer P, Arrigo R, Deacon L, Quevedo Garzon W, Roy K, Large A, Stephens C, Watts A, Larkin P, Hand M, Wang H, Pratt L, Mudd JJ, Richardson T, Patel S, Hillman M, Scott S. Ambient-pressure endstation of the Versatile Soft X-ray (VerSoX) beamline at Diamond Light Source. JOURNAL OF SYNCHROTRON RADIATION 2020; 27:1153-1166. [PMID: 32876589 PMCID: PMC7467337 DOI: 10.1107/s1600577520009157] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 07/05/2020] [Indexed: 05/24/2023]
Abstract
The ambient-pressure endstation and branchline of the Versatile Soft X-ray (VerSoX) beamline B07 at Diamond Light Source serves a very diverse user community studying heterogeneous catalysts, pharmaceuticals and biomaterials under realistic conditions, liquids and ices, and novel electronic, photonic and battery materials. The instrument facilitates studies of the near-surface chemical composition, electronic and geometric structure of a variety of samples using X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy in the photon energy range from 170 eV to 2800 eV. The beamline provides a resolving power hν/Δ(hν) > 5000 at a photon flux > 1010 photons s-1 over most of its energy range. By operating the optical elements in a low-pressure oxygen atmosphere, carbon contamination can be almost completely eliminated, which makes the beamline particularly suitable for carbon K-edge NEXAFS. The endstation can be operated at pressures up to 100 mbar, whereby XPS can be routinely performed up to 30 mbar. A selection of typical data demonstrates the capability of the instrument to analyse details of the surface composition of solid samples under ambient-pressure conditions using XPS and NEXAFS. In addition, it offers a convenient way of analysing the gas phase through X-ray absorption spectroscopy. Short XPS spectra can be measured at a time scale of tens of seconds. The shortest data acquisition times for NEXAFS are around 0.5 s per data point.
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Affiliation(s)
- Georg Held
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
- Department of Chemistry, University of Reading, Reading, United Kingdom
| | | | | | - Pilar Ferrer
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | - Rosa Arrigo
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
- School of Science, Engineering and Environment, University of Salford, Manchester, United Kingdom
| | - Liam Deacon
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | - Wilson Quevedo Garzon
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
- Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, Germany
| | - Kanak Roy
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | - Alex Large
- Department of Chemistry, University of Reading, Reading, United Kingdom
| | | | - Andrew Watts
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | - Paul Larkin
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | - Matthew Hand
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | | | - Linda Pratt
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | - James J. Mudd
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | | | - Suren Patel
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
| | | | - Stewart Scott
- Diamond Light Source Ltd, Oxfordshire, United Kingdom
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16
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Karatok M, Egle T, Mehar V, O’Connor CR, Yu MH, Friend CM, Weaver JF. Reduction of Oxidized Pd/Ag(111) Surfaces by H 2: Sensitivity to PdO Island Size and Dispersion. ACS Catal 2020. [DOI: 10.1021/acscatal.0c03037] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mustafa Karatok
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Tobias Egle
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Vikram Mehar
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Christopher R. O’Connor
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Ming-Hung Yu
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Cynthia M. Friend
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Jason F. Weaver
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, United States
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17
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Song D, Li Y, Liu X, Zhang Z, Shen X. Hot-Atom Mechanism in Syngas Methanation on Precovered Pd(100) Surfaces. J Phys Chem Lett 2020; 11:5312-5317. [PMID: 32538635 DOI: 10.1021/acs.jpclett.0c01469] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The excess energy of subsurface hydrogen species may facilitate overcoming reaction barriers and remarkably alters the reaction pathways. We present an in-depth study on the different reactivity of surface and subsurface hydrogen species in syngas methanation on the O/C-covered Pd(100) by using density functional theory calculations and microkinetic simulations. It is shown that the apparent energy barriers to form H2O and CH4 are reduced by 0.87 and 0.61 eV for the case in which the hot subsurface hydrogen species are involved in the whole hydrogenation process. The activity of O-covered Pd(100) is better than that of the C-covered surface, and the reactivity of subsurface hydrogen species is much higher than that of surface hydrogen species under ambient conditions. Increasing CO partial pressure strongly enhances the reactivity of subsurface hydrogen species in syngas methanation on the O-covered Pd(100). These important results are helpful for understanding the hot-atom mechanism through subsurface heterogeneous catalysis.
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Affiliation(s)
- Dandan Song
- Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education, Zhengzhou University, Zhengzhou 450001, China
| | - Yuanjie Li
- Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education, Zhengzhou University, Zhengzhou 450001, China
| | - Xiaojing Liu
- Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education, Zhengzhou University, Zhengzhou 450001, China
| | - Zhaojun Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China
| | - Xiangjian Shen
- Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education, Zhengzhou University, Zhengzhou 450001, China
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18
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Li X, Wang X, Roy K, van Bokhoven JA, Artiglia L. Role of Water on the Structure of Palladium for Complete Oxidation of Methane. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01069] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Xiansheng Li
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Xing Wang
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Kanak Roy
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Jeroen A. van Bokhoven
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Luca Artiglia
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Laboratory of Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
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19
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Inverse temperature hysteresis and self-sustained oscillations in CO oxidation over Pd at elevated pressures of reaction mixture: Experiment and mathematical modeling. Chem Eng Sci 2020. [DOI: 10.1016/j.ces.2019.115312] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Luneau M, Shirman T, Foucher AC, Duanmu K, Verbart DM, Sautet P, Stach EA, Aizenberg J, Madix RJ, Friend CM. Achieving High Selectivity for Alkyne Hydrogenation at High Conversions with Compositionally Optimized PdAu Nanoparticle Catalysts in Raspberry Colloid-Templated SiO2. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04243] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | - Alexandre C. Foucher
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | | | - David M.A. Verbart
- Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | | | - Eric A. Stach
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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21
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Wang Z, Hu P. Identifying the general trend of activity of non-stoichiometric metal oxide phases for CO oxidation on Pd(111). Sci China Chem 2019. [DOI: 10.1007/s11426-018-9445-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Saint-Lager MC, Languille MA, Aires FJCS, Bailly A, Garaudée S, Ehret E, Robach O. Carbon Monoxide Oxidation Promoted by a Highly Active Strained PdO Layer at the Surface of Au30Pd70(110). ACS Catal 2019. [DOI: 10.1021/acscatal.8b04190] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Marie-Angélique Languille
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON − UMR 5256, 69626 Villeurbanne, France
| | - Francisco J. Cadete Santos Aires
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON − UMR 5256, 69626 Villeurbanne, France
- Laboratory for Catalytic Research, National Research Tomsk State University, 634050 Tomsk, Russia
| | - Aude Bailly
- CNRS Institut Néel and Université Grenoble Alpes, 38000 Grenoble, France
| | - Stéphanie Garaudée
- CNRS Institut Néel and Université Grenoble Alpes, 38000 Grenoble, France
| | - Eric Ehret
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON − UMR 5256, 69626 Villeurbanne, France
| | - Odile Robach
- Université Grenoble Alpes, CEA, INAC-MEM, 38000 Grenoble, France
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23
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Cheng X, Wang Z, Mao Y, Hu P. Evidence of the O–Pd–O and Pd–O4 structure units as oxide seeds and their origin on Pd(211): revealing the mechanism of surface oxide formation. Phys Chem Chem Phys 2019; 21:6499-6505. [DOI: 10.1039/c8cp06224b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The formation of surface oxides on metal surfaces is not only important in materials science, but also of significance in heterogeneous catalysis due to the fact that during most oxidation reactions the metal catalysts are inevitably oxidized, which may cause dramatic consequences in the reactions.
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Affiliation(s)
- Xiran Cheng
- School of Chemistry and Chemical Engineering
- The Queen's University Belfast
- UK
| | - Ziyun Wang
- School of Chemistry and Chemical Engineering
- The Queen's University Belfast
- UK
| | - Yu Mao
- School of Chemistry and Chemical Engineering
- The Queen's University Belfast
- UK
| | - P. Hu
- School of Chemistry and Chemical Engineering
- The Queen's University Belfast
- UK
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24
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Tamaoka T, Yoshida H, Takeda S. Oxidation and hydrogenation of Pd: suppression of oxidation by prolonged H 2exposure. RSC Adv 2019; 9:9113-9116. [PMID: 35517653 PMCID: PMC9062043 DOI: 10.1039/c9ra00436j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 03/11/2019] [Indexed: 01/01/2023] Open
Abstract
We investigate the phase transition of a Pd surface in both oxidizing and reducing environments by environmental transmission electron microscopy (ETEM). ETEM allows us to study sequential exposure of Pd to O2 and H2 in the same TEM conditions. First, under ETEM observation, oxidation occurs at step edges but it can also occur at terraces. Second, as the most important result, we observed a novel process where previous exposure to H2 suppresses new oxidation of the Pd surface. Third, we show by electron energy loss spectroscopy (EELS) that this process, suppression of oxidation by previous exposure to H2, is not due to the formation of bulk β-phase Pd hydride. We also demonstrate that this process is not present in Pt. Finally, we discuss the hypothesis to explain this phenomenon: formation of surface–Pd–hydride suppresses the new oxidation. This observation, suppression of oxidation by H2 exposure, may eventually lead to new breakthroughs. Oxidation of the Pd surface exhibits dependence on the history of pre-exposure to H2.![]()
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Affiliation(s)
- Takehiro Tamaoka
- The Institute of Scientific and Industrial Research
- Osaka University
- Ibaraki
- Japan
- Department of Materials and Manufacturing Science
| | - Hideto Yoshida
- The Institute of Scientific and Industrial Research
- Osaka University
- Ibaraki
- Japan
| | - Seiji Takeda
- The Institute of Scientific and Industrial Research
- Osaka University
- Ibaraki
- Japan
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25
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Kondoh H, Toyoshima R, Shirahata N, Hoda A, Yoshida M, Amemiya K, Mase K, Mun BS. Element selective oxidation on Rh-Pd bimetallic alloy surfaces. Phys Chem Chem Phys 2018; 20:28419-28424. [PMID: 30403236 DOI: 10.1039/c8cp05998e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The interactions between oxygen and Rh-Pd bimetallic alloy surfaces were investigated using surface sensitive experimental techniques and density functional theory calculations. The alloy surfaces were oxidized under 10-5 Torr and 100 mTorr oxygen upon heating above 250 °C. A thin Rh oxide layer was preferentially formed on a Rh1Pd9(100) surface, while a thin Pd oxide layer was formed on a Rh1Pd9(111) surface, though the Rh oxide is thermodynamically more stable irrespective of the surface orientation. Chemical analyses revealed that the initial Rh fraction for the (111) surface was significantly lower than that for the (100) surface, which suggests that the oxidized element on the surface is kinetically selected depending on the near surface initial composition.
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Affiliation(s)
- Hiroshi Kondoh
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-Ku, Yokohama, 223-8522, Japan.
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26
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Kerger P, Vogel D, Rohwerder M. Electrochemistry in ultra-high vacuum: The fully transferrable ultra-high vacuum compatible electrochemical cell. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:113102. [PMID: 30501323 DOI: 10.1063/1.5046389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/16/2018] [Indexed: 06/09/2023]
Abstract
A new experimental setup for in situ/operando investigations of redox reactions is introduced. This setup, in combination with ultra-high vacuum (UHV) methods from the field of surface science, provides completely new possibilities to investigate electrochemical redox reactions. Two types of cells are distinguished conceptionally: in the permeation configuration, the working electrode is electrochemically polarised on one side of a membrane (entry side), leading to atomic hydrogen uptake, and allowing proton and electron exchange between the entry and the other side (exit side) of the membrane. Here it is found that the applied potential on the entry side shows a 1:1 correlation with the measured potential on the exit side. The concept of the "window" cell requires ultra-thin, electron transparent "windows," such as single layer graphene, for X-ray photoelectron spectroscopy or X-ray transparent silicon nitride "windows" for X-ray absorption spectroscopy. In this case, the solid/liquid interface can be directly probed under applied potentials. In both configurations, the applied potential is measured with a palladium hydride reference electrode, with so far unseen precision and long-term stability. The cell design is constructed with regard to transferability within a UHV system, allowing sample preparation, and a modular construction, allowing a straightforward changeover between these two configurations. As a first application, an approach based on atomic hydrogen is presented. Further application concepts are discussed. The setup functionality is demonstrated by the example of in situ/operando investigation of the palladium oxide reduction.
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Affiliation(s)
- P Kerger
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
| | - D Vogel
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
| | - M Rohwerder
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
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27
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Möller C, Fedderwitz H, Noguera C, Goniakowski J, Nilius N. Temperature-dependent phase evolution of copper-oxide thin-films on Au(111). Phys Chem Chem Phys 2018; 20:5636-5643. [DOI: 10.1039/c7cp08387d] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
STM and DFT calculations are employed to explore structural phase transitions in thin copper-oxide films grown on Au(111).
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Affiliation(s)
- Christoph Möller
- Carl von Ossietzky Universität Oldenburg
- Institut für Physik
- Oldenburg D-26111
- Germany
| | - Hanna Fedderwitz
- Carl von Ossietzky Universität Oldenburg
- Institut für Physik
- Oldenburg D-26111
- Germany
| | - Claudine Noguera
- CNRS
- Institut des Nanosciences de Paris
- UMR 7588
- Paris F-75005
- France
| | | | - Niklas Nilius
- Carl von Ossietzky Universität Oldenburg
- Institut für Physik
- Oldenburg D-26111
- Germany
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28
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Weaver JF, Choi J, Mehar V, Wu C. Kinetic Coupling among Metal and Oxide Phases during CO Oxidation on Partially Reduced PdO(101): Influence of Gas-Phase Composition. ACS Catal 2017. [DOI: 10.1021/acscatal.7b02570] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jason F. Weaver
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Juhee Choi
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Vikram Mehar
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Chengjun Wu
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, United States
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29
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Suprun EA, Salanov AN. Dissolution of oxygen in polycrystalline palladium at $${P_{{O_2}}}$$ P O 2 = 100 Pa and temperatures of 500 to 950 K. KINETICS AND CATALYSIS 2017. [DOI: 10.1134/s0023158417010116] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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30
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Boes JR, Kitchin JR. Neural network predictions of oxygen interactions on a dynamic Pd surface. MOLECULAR SIMULATION 2017. [DOI: 10.1080/08927022.2016.1274984] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Jacob R. Boes
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - John R. Kitchin
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
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31
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van Spronsen MA, Frenken JWM, Groot IMN. Surface science under reaction conditions: CO oxidation on Pt and Pd model catalysts. Chem Soc Rev 2017; 46:4347-4374. [DOI: 10.1039/c7cs00045f] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Application of surface-science techniques, such as XPS, SXRD, STM, and IR spectroscopy under catalytic reactions conditions yield new structural and chemical information. Recent experiments focusing on CO oxidation over Pt and Pd model catalysts were reviewed.
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Affiliation(s)
| | - Joost W. M. Frenken
- Advanced Research Center for Nanolithography
- 1090 BA Amsterdam
- The Netherlands
| | - Irene M. N. Groot
- Leiden Institute of Chemistry
- Leiden University
- 2300 RA Leiden
- The Netherlands
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32
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Shipilin M, Gustafson J, Zhang C, Merte LR, Lundgren E. Step dynamics and oxide formation during CO oxidation over a vicinal Pd surface. Phys Chem Chem Phys 2016; 18:20312-20. [PMID: 26805438 DOI: 10.1039/c5cp07488f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In an attempt to bridge the material and pressure gaps - two major challenges for an atomic scale understanding of heterogeneous catalysis - we employed high-energy surface X-ray diffraction as a tool to study the Pd(553) surface in situ under changing reaction conditions during CO oxidation. The diffraction patterns recorded under CO rich reaction conditions are characteristic for the metallic state of the surface. In an environment with low excess of O2 over the reaction stoichiometry, the surface seems to accommodate oxygen atoms along the steps forming one or several subsequent adsorbate structures and rapidly transforms into a combination of (332), (111) and (331) facets likely providing the room for the formation of a surface oxide. For the case of large excess of O2, the diffraction data show the presence of a multilayer PdO with the [101] crystallographic direction parallel to the [111] and the [331] directions of the substrate. The reconstructions in O2 excess are to a large extent similar to those previously reported for pure O2 exposures by Westerström et al. [R. Westerström et al., Phys. Rev. B: Condens. Matter Mater. Phys., 2007, 76, 155410].
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Affiliation(s)
- Mikhail Shipilin
- Division of Synchrotron Radiation Research, Lund University, SE-22100 Lund, Sweden.
| | - Johan Gustafson
- Division of Synchrotron Radiation Research, Lund University, SE-22100 Lund, Sweden.
| | - Chu Zhang
- Division of Synchrotron Radiation Research, Lund University, SE-22100 Lund, Sweden.
| | | | - Edvin Lundgren
- Division of Synchrotron Radiation Research, Lund University, SE-22100 Lund, Sweden.
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33
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Salanov AN, Suprun EA. Mechanism of the decomposition of the surface oxide film on polycrystalline palladium. KINETICS AND CATALYSIS 2016. [DOI: 10.1134/s0023158416020129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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35
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Kondoh H, Toyoshima R, Monya Y, Yoshida M, Mase K, Amemiya K, Mun BS. In situ analysis of catalytically active Pd surfaces for CO oxidation with near ambient pressure XPS. Catal Today 2016. [DOI: 10.1016/j.cattod.2015.05.016] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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36
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Price R, Eralp-Erden T, Crumlin E, Rani S, Garcia S, Smith R, Deacon L, Euaruksakul C, Held G. The Partial Oxidation of Methane Over Pd/Al2O3 Catalyst Nanoparticles Studied In-Situ by Near Ambient-Pressure X-ray Photoelectron Spectroscopy. Top Catal 2016. [DOI: 10.1007/s11244-015-0520-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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37
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38
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Schauermann S, Freund HJ. Model Approach in Heterogeneous Catalysis: Kinetics and Thermodynamics of Surface Reactions. Acc Chem Res 2015; 48:2775-82. [PMID: 26366783 DOI: 10.1021/acs.accounts.5b00237] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Heterogeneous catalysts are widely employed in technological applications, such as chemical manufacturing, energy harvesting, conversion and storage, and environmental technology. Often they consist of disperse metal nanoparticles anchored onto a morphologically complex oxide support. The compositional and structural complexity of such nanosized systems offers many degrees of freedom for tuning their catalytic performance. However, a rational design of heterogeneous catalysts based on an atomistic-level understanding of underlying surface processes has not been fully achieved so far and remains one of the primary goals for catalysis research. In our group, we developed concepts for replacing highly complex real supported catalysts by simplified model systems, which complexity can be gradually increased in order to mimic certain structural aspects of practically relevant catalysts in a controlled way. Well-defined model systems consisting of metal-nanoparticle ensembles supported on planar oxide substrates have proven to provide a successful approach to achieve fundamental insights into heterogeneous catalysis. In this Account, two mechanistic case studies focusing on an atomistic-level understanding of surface chemistry are presented in which we investigate how the nanoscopic nature of metal clusters affects their interaction with the adsorbates and the reactive processes. Particularly, we investigate the effects of the particle size and the flexibility of the atoms constituting metal clusters on the binding energy of gas-phase adsorbates, such as CO and oxygen. We identified two major structural factors determining the binding energy of gas phase adsorbates on metal nanoparticles: the local configuration of the adsorption site and the particle size. While the effect of the local configuration of the adsorption site was found to be adsorbate specific, the reduction of the cluster size results in a pronounced decrease of binding energy for both adsorbates and appears to be a general trend. In the second case study, we address the role of the surface modifiers, such as carbon, on the process of hydrogen diffusion into volume of Pd nanoparticles that was previously identified is an important step in hydrogenation chemistry. We provide for the first time direct experimental evidence that, inline with the recent theoretical predictions, the atomically flexible low-coordinated surface sites on Pd particles play a crucial role in the diffusion process and that their selective modification with carbon results in marked facilitation of subsurface hydrogen diffusion. By virtue of these examples, we demonstrate how model studies on complex nanostructured materials may provide an atomistic view of processes at the gas-solid interface related to heterogeneous catalysis.
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Affiliation(s)
- Swetlana Schauermann
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
- Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Strasse 1, 24118 Kiel, Germany
| | - Hans-Joachim Freund
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
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39
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Sezen H, Alemán B, Amati M, Dalmiglio M, Gregoratti L. Spatially Resolved Chemical Characterization with Scanning Photoemission Spectromicroscopy: Towards Near-Ambient-Pressure Experiments. ChemCatChem 2015. [DOI: 10.1002/cctc.201500637] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Hikmet Sezen
- Elettra-Sincrotrone Trieste SCpA; SS14-Km163.5 in Area Science Park 34149 Trieste Italy
| | - Belén Alemán
- IMDEA Materials Institute; c/Eric Kandel 2, Getafe 28960 Madrid Spain
| | - Matteo Amati
- Elettra-Sincrotrone Trieste SCpA; SS14-Km163.5 in Area Science Park 34149 Trieste Italy
| | - Matteo Dalmiglio
- Joint Research Centre, Institute for Health and Consumer Protection, Nanobiosciences Unit; Via Enrico Fermi 2749 Ispra (VA) Italy
| | - Luca Gregoratti
- Elettra-Sincrotrone Trieste SCpA; SS14-Km163.5 in Area Science Park 34149 Trieste Italy
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40
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Jürgensen A, Heutz N, Raschke H, Merz K, Hergenröder R. Behavior of Supported Palladium Oxide Nanoparticles under Reaction Conditions, Studied with near Ambient Pressure XPS. Anal Chem 2015; 87:7848-56. [DOI: 10.1021/acs.analchem.5b01531] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Astrid Jürgensen
- Leibniz Institut für Analytische Wissenschaften − ISAS − e.V., Bunsen-Kirchhoff-Straße
11, 44139 Dortmund, Germany
| | - Niels Heutz
- Lehrstuhl
für Anorganische Chemie I, Fakultät für Chemie
und Biochemie, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum, Germany
| | - Hannes Raschke
- Leibniz Institut für Analytische Wissenschaften − ISAS − e.V., Bunsen-Kirchhoff-Straße
11, 44139 Dortmund, Germany
| | - Klaus Merz
- Lehrstuhl
für Anorganische Chemie I, Fakultät für Chemie
und Biochemie, Ruhr-Universität Bochum, Universitätsstraße 150, D-44801 Bochum, Germany
| | - Roland Hergenröder
- Leibniz Institut für Analytische Wissenschaften − ISAS − e.V., Bunsen-Kirchhoff-Straße
11, 44139 Dortmund, Germany
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41
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Hjort M, Knutsson JV, Mandl B, Deppert K, Lundgren E, Timm R, Mikkelsen A. Surface morphology of Au-free grown nanowires after native oxide removal. NANOSCALE 2015; 7:9998-10004. [PMID: 25981415 DOI: 10.1039/c5nr01874a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Using scanning tunneling microscopy, we evaluate the surface structure and morphology down to the atomic scale for micrometers along Au-free grown InAs nanowires (NWs) free from native oxide. We find that removal of the native oxide (which covers the NWs upon exposure to the ambient air) using atomic hydrogen does not alter the underlying step structure. Imaging with sub-nanometer resolution along the NWs, we find an extremely low tapering (diameter change along the NW) of 1.7 ± 0.5 Åμm(-1). A surface morphology with monolayer high islands, whose shape was influenced by stacking faults, was found to cover the NWs and was attributed to the decomposed native oxide. The appearance of point defects in the form of As-vacancies at the surface is analyzed and we set limits to the amount of carbon impurities in the NWs.
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Affiliation(s)
- Martin Hjort
- Department of Physics and the Nanometer Structure Consortium, Lund University, P.O. Box 118, 22 100 Lund, Sweden.
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42
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Lang SM, Fleischer I, Bernhardt TM, Barnett RN, Landman U. Low-Temperature CO Oxidation Catalyzed by Free Palladium Clusters: Similarities and Differences to Pd Surfaces and Supported Particles. ACS Catal 2015. [DOI: 10.1021/cs5016222] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Sandra M. Lang
- Institute
of Surface Chemistry and Catalysis, University of Ulm, Albert-Einstein-Allee
47, 89069 Ulm, Germany
| | - Irene Fleischer
- Institute
of Surface Chemistry and Catalysis, University of Ulm, Albert-Einstein-Allee
47, 89069 Ulm, Germany
| | - Thorsten M. Bernhardt
- Institute
of Surface Chemistry and Catalysis, University of Ulm, Albert-Einstein-Allee
47, 89069 Ulm, Germany
| | - Robert N. Barnett
- School
of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, United States
| | - Uzi Landman
- School
of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, United States
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43
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Toyoshima R, Kondoh H. In-situ observations of catalytic surface reactions with soft x-rays under working conditions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:083003. [PMID: 25667354 DOI: 10.1088/0953-8984/27/8/083003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Catalytic chemical reactions proceeding on solid surfaces are an important topic in fundamental science and industrial technologies such as energy conversion, pollution control and chemical synthesis. Complete understanding of the heterogeneous catalysis and improving its efficiency to an ultimate level are the eventual goals for many surface scientists. Soft x-ray is one of the prime probes to observe electronic and structural information of the target materials. Most studies in surface science using soft x-rays have been performed under ultra-high vacuum conditions due to the technical limitation, though the practical catalytic reactions proceed under ambient pressure conditions. However, recent developments of soft x-ray based techniques operating under ambient pressure conditions have opened a door to the in-situ observation of materials under realistic environments. The near-ambient-pressure x-ray photoelectron spectroscopy (NAP-XPS) using synchrotron radiation enables us to observe the chemical states of surfaces of condensed matters under the presence of gas(es) at elevated pressures, which has been hardly conducted with the conventional XPS technique. Furthermore, not only the NAP-XPS but also ambient-pressure compatible soft x-ray core-level spectroscopies, such as near-edge absorption fine structure (NEXAFS) and x-ray emission spectroscopy (XES), have been significantly contributing to the in-situ observations. In this review, first we introduce recent developments of in-situ observations using soft x-ray techniques and current status. Then we present recent new findings on catalytically active surfaces using soft x-ray techniques, particularly focusing on the NAP-XPS technique. Finally we give a perspective on the future direction of this emerging technique.
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44
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Li J, Li L, Zhou G. The onset of sub-surface oxidation induced by defects in a chemisorbed oxygen layer. J Chem Phys 2015; 142:084701. [DOI: 10.1063/1.4913237] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jonathan Li
- Department of Physics, Applied Physics and Astronomy and Multidisciplinary Program in Materials Science and Engineering, State University of New York, Binghamton, New York 13902, USA
| | - Liang Li
- Department of Mechanical Engineering and Multidisciplinary Program in Materials Science and Engineering, State University of New York, Binghamton, New York 13902, USA
| | - Guangwen Zhou
- Department of Mechanical Engineering and Multidisciplinary Program in Materials Science and Engineering, State University of New York, Binghamton, New York 13902, USA
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45
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Popa C, Zhu T, Tranca I, Kaghazchi P, Jacob T, Hensen EJM. Structure of palladium nanoparticles under oxidative conditions. Phys Chem Chem Phys 2015; 17:2268-73. [PMID: 25486336 DOI: 10.1039/c4cp01761g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using density functional theory (DFT) and thermodynamic considerations we study the shape and stability of Pd nanoparticles in oxygen-lean and oxygen-rich atmospheres. We find that at very high oxygen coverage cubes exposing (100) faces will form, which are stabilized due to the formation of a O/(√5 × √5)R27° overlayer. The shape of oxygen-covered Pd and Pt nanoparticles is compared in this study.
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Affiliation(s)
- Cristina Popa
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Den Dolech 2, 5612 AZ Eindhoven, The Netherlands.
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46
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Liu H, Tao K, Xiong C, Zhou S. Controlled synthesis of Pd–NiO@SiO2 mesoporous core–shell nanoparticles and their enhanced catalytic performance for p-chloronitrobenzene hydrogenation with H2. Catal Sci Technol 2015. [DOI: 10.1039/c4cy00996g] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pd–NiO@SiO2 nanocatalysts illustrated a superior catalytic performance for catalytic p-chloronitrobenzene hydrogenation to PdNi@SiO2 and Pd@SiO2 nanocatalysts.
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Affiliation(s)
- Hongmei Liu
- College of Materials and Chemical Engineering
- Hainan University
- Haikou
- PR China
- Ningbo Institute of Materials Technology and Engineering
| | - Kai Tao
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
- PR China
| | - Chunrong Xiong
- College of Materials and Chemical Engineering
- Hainan University
- Haikou
- PR China
| | - Shenghu Zhou
- Ningbo Institute of Materials Technology and Engineering
- Chinese Academy of Sciences
- Ningbo
- PR China
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47
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Affiliation(s)
- Zhiyao Duan
- Department
of Chemistry and
the Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas 78712-0165, United States
| | - Graeme Henkelman
- Department
of Chemistry and
the Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas 78712-0165, United States
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48
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Schauermann S, Silbaugh TL, Campbell CT. Single-Crystal Adsorption Calorimetry on Well-Defined Surfaces: From Single Crystals to Supported Nanoparticles. CHEM REC 2014; 14:759-74. [DOI: 10.1002/tcr.201402022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Swetlana Schauermann
- Fritz-Haber-Institut der Max-Planck-Gesellschaft; Faradayweg 4-6 14195 Berlin Germany
| | - Trent L. Silbaugh
- Department of Chemical Engineering; University of Washington; Seattle Washington 98195-1750 USA
| | - Charles T. Campbell
- Department of Chemical Engineering; University of Washington; Seattle Washington 98195-1750 USA
- Department of Chemistry; University of Washington; Seattle Washington 98195-1700 USA
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49
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Yoshida M, Kondoh H. In Situ Observation of Model Catalysts under Reaction Conditions Using X-ray Core-Level Spectroscopy. CHEM REC 2014; 14:806-18. [DOI: 10.1002/tcr.201402025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Masaaki Yoshida
- Department of Chemistry; Keio University; 3-14-1 Hiyoshi Yokohama 223-8522 Japan
| | - Hiroshi Kondoh
- Department of Chemistry; Keio University; 3-14-1 Hiyoshi Yokohama 223-8522 Japan
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50
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Van den Bossche M, Martin NM, Gustafson J, Hakanoglu C, Weaver JF, Lundgren E, Grönbeck H. Effects of non-local exchange on core level shifts for gas-phase and adsorbed molecules. J Chem Phys 2014; 141:034706. [DOI: 10.1063/1.4889919] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- M. Van den Bossche
- Department of Applied Physics and Competence Centre for Catalysis, Chalmers University of Technology, Göteborg, Sweden
| | - N. M. Martin
- Division of Synchrotron Radiation Research, Lund University, Lund, Sweden
| | - J. Gustafson
- Division of Synchrotron Radiation Research, Lund University, Lund, Sweden
| | - C. Hakanoglu
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, USA
| | - J. F. Weaver
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, USA
| | - E. Lundgren
- Division of Synchrotron Radiation Research, Lund University, Lund, Sweden
| | - H. Grönbeck
- Department of Applied Physics and Competence Centre for Catalysis, Chalmers University of Technology, Göteborg, Sweden
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