1
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Ascrizzi E, Goniakowski J, Yang J, Agnoli S, Ferrari AM. DFT study of the moiré pattern of FeO monolayer on Au(111). Phys Chem Chem Phys 2024; 26:20103-20111. [PMID: 39010758 DOI: 10.1039/d4cp01546k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Metal oxides are a class of material of particular interest for catalytic purposes. Among them the iron oxide as a monolayer supported on gold, FeO/Au, stands out for its capability to promote the CO oxidation and the dissociation of O2 and H2. In this work, we use density functional theory calculations to characterize interfacial properties of this heterostructure. We consider a FeO/Au realistic model system, managing to reproduce the moiré pattern experimentally found. Specific features of the high-symmetry domains of the moiré are identified, providing a robust ground for establishing a structure-activity relationship and guessing how the surface would behave in catalytic conditions. We also describe a strategy to model smaller systems representative of each high-symmetry domains of the moiré, which will be useful in the future to model catalytic reaction mechanisms.
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Affiliation(s)
- Eleonora Ascrizzi
- Dipartimento di Chimica, Università di Torino, via Pietro Giuria 5, I-10125 Turin, Italy.
| | - Jacek Goniakowski
- CNRS, Sorbonne Université, Institut des NanoSciences de Paris, UMR 7588, 4 Place Jussieu, F-75005 Paris, France
| | - Jijin Yang
- Department of Chemical Sciences, University of Padua, via Francesco Marzolo, 1, Padua 35131, Italy
| | - Stefano Agnoli
- Department of Chemical Sciences, University of Padua, via Francesco Marzolo, 1, Padua 35131, Italy
| | - Anna Maria Ferrari
- Dipartimento di Chimica, Università di Torino, via Pietro Giuria 5, I-10125 Turin, Italy.
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2
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Liu D, Li L, Jiang N. Nanoscale Chemical Probing of Metal-Supported Ultrathin Ferrous Oxide via Tip-Enhanced Raman Spectroscopy and Scanning Tunneling Microscopy. CHEMICAL & BIOMEDICAL IMAGING 2024; 2:345-351. [PMID: 38817320 PMCID: PMC11134605 DOI: 10.1021/cbmi.4c00015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Revised: 03/04/2024] [Accepted: 03/11/2024] [Indexed: 06/01/2024]
Abstract
Metal-supported ultrathin ferrous oxide (FeO) has attracted immense interest in academia and industry due to its widespread applications in heterogeneous catalysis. However, chemical insight into the local structural characteristics of FeO, despite its critical importance in elucidating structure-property relationships, remains elusive. In this work, we report the nanoscale chemical probing of gold (Au)-supported ultrathin FeO via ultrahigh-vacuum tip-enhanced Raman spectroscopy (UHV-TERS) and scanning tunneling microscopy (STM). For comparative analysis, single-crystal Au(111) and Au(100) substrates are used to tune the interfacial properties of FeO. Although STM images show distinctly different moiré superstructures on FeO nanoislands on Au(111) and Au(100), TERS demonstrates the same chemical nature of FeO by comparable vibrational features. In addition, combined TERS and STM measurements identify a unique wrinkled FeO structure on Au(100), which is correlated to the reassembly of the intrinsic Au(100) surface reconstruction due to FeO deposition. Beyond revealing the morphologies of ultrathin FeO on Au substrates, our study provides a thorough understanding of the local interfacial properties and interactions of FeO on Au, which could shed light on the rational design of metal-supported FeO catalysts. Furthermore, this work demonstrates the promising utility of combined TERS and STM in chemically probing the structural properties of metal-supported ultrathin oxides on the nanoscale.
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Affiliation(s)
- Dairong Liu
- Department
of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, United States
| | - Linfei Li
- Department
of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, United States
| | - Nan Jiang
- Department
of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, United States
- Department
of Physics, University of Illinois Chicago, Chicago, Illinois 60607, United States
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3
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Liu Y, Lin L, Yu L, Mu R, Fu Q. Spatially Separated Active Sites Enable Selective CO Oxidation Reaction on Oxide Catalyst. J Phys Chem Lett 2023; 14:9780-9786. [PMID: 37882533 DOI: 10.1021/acs.jpclett.3c02247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
The search for efficient non-noble-metal catalysts able to perform selective oxidation reactions is of great importance, with relevance to many catalytic processes. However, this is often hampered because the origin of the selectivity remains controversial, particularly for reactions catalyzed by oxides. Here, combining high-pressure surface imaging techniques and theoretical calculations, we identify that spatially separated active sites for O2 activation and H2 adsorption on an ultrathin Mn3O4 surface enable selective oxidation of CO over H2. Theoretical calculations reveal that Mn-O pairs for H2 dissociation are separated from Mn-Mn pairs for the formation of adsorbed O2* so that H2 has to surmount much higher barriers for both H2 dissociation and H diffusion while CO can directly react with O2* following the Eley-Rideal process. Our study sheds light on the atomic-level understanding of the surface structure-dependent selective oxidation reaction on oxide catalysts.
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Affiliation(s)
- Yijing Liu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Le Lin
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Liang Yu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Rentao Mu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Qiang Fu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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4
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Liu C, Lin L, Wu H, Liu Y, Mu R, Fu Q. Activating lattice oxygen of single-layer ZnO for the catalytic oxidation reaction. Phys Chem Chem Phys 2023; 25:20121-20127. [PMID: 37462941 DOI: 10.1039/d3cp02580b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Tuning an oxide/metal interface is of critical importance for the performance enhancement of many heterogeneous catalytic reactions. However, catalytic oxidation occurring at the interface between non-reducible oxide and metal has been challenging, since non-reducible oxides hardly lose their lattice oxygen (OL) or dissociate O2 from the gas phase. In this work, a ZnO monolayer film on Au(111) is used as an inverse catalyst to investigate CO oxidation occurring at the ZnO/Au(111) interface via high pressure scanning tunneling microscopy. Surface science experiments indicate that oxygen intercalation under the ZnO monolayer film, termed ZnO/O/Au(111), can be achieved via a surface reaction with 1 × 10-6 mbar O3. Subsequent exposure of the formed ZnO/O/Au(111) surface to mbar CO at room temperature leads to the recovery of the pristine ZnO/Au(111) surface. Theoretical calculations reveal that OL adjacent to intercalated oxygen (Oint) is activated due to the OL-Zn-Oint bonding and surface corrugation, which can be directly involved in CO oxidation. Subsequently, Oint migrates to the formed oxygen vacancy from the subsurface resuming the pristine ZnO structure. These results thus reveal that oxygen intercalation underneath single-layer ZnO will strongly boost the oxidation reaction via activating adjacent lattice oxygen atoms.
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Affiliation(s)
- Changping Liu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Le Lin
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Hao Wu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Yijing Liu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rentao Mu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Qiang Fu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
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5
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Adamsen KC, Petrik NG, Dononelli W, Kimmel GA, Xu T, Li Z, Lammich L, Hammer B, Lauritsen JV, Wendt S. Origin of hydroxyl pair formation on reduced anatase TiO 2(101). Phys Chem Chem Phys 2023; 25:13645-13653. [PMID: 37145025 DOI: 10.1039/d3cp01051a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The interaction of water with metal oxide surfaces is of key importance to several research fields and applications. Because of its ability to photo-catalyze water splitting, reducible anatase TiO2 (a-TiO2) is of particular interest. Here, we combine experiments and theory to study the dissociation of water on bulk-reduced a-TiO2(101). Following large water exposures at room temperature, point-like protrusions appear on the a-TiO2(101) surface, as shown by scanning tunneling microscopy (STM). These protrusions originate from hydroxyl pairs, consisting of terminal and bridging OH groups, OHt/OHb, as revealed by infrared reflection absorption spectroscopy (IRRAS) and valence band experiments. Utilizing density functional theory (DFT) calculations, we offer a comprehensive model of the water/a-TiO2(101) interaction. This model also explains why the hydroxyl pairs are thermally stable up to ∼480 K.
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Affiliation(s)
- Kræn C Adamsen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark.
| | - Nikolay G Petrik
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
| | - Wilke Dononelli
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
- MAPEX Center for Materials and Processes, Bremen Center for Computational Materials Science and Hybrid Materials Interfaces Group, Bremen University, 28359 Bremen, Germany
| | - Greg A Kimmel
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
| | - Tao Xu
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark.
| | - Zheshen Li
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Lutz Lammich
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark.
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Bjørk Hammer
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Jeppe V Lauritsen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark.
| | - Stefan Wendt
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C, Denmark.
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6
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Yi Z, Lin L, Chang Y, Luo X, Gao J, Mu R, Ning Y, Fu Q, Bao X. Dynamic transformation between bilayer islands and dinuclear clusters of Cr oxide on Au(111) through environment and interface effects. Proc Natl Acad Sci U S A 2022; 119:e2120716119. [PMID: 35605120 PMCID: PMC9295788 DOI: 10.1073/pnas.2120716119] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 04/15/2022] [Indexed: 11/18/2022] Open
Abstract
SignificanceFor oxide catalysts, it is important to elucidate and further control their atomic structures. In this work, well-defined CrO2 bilayer islands and Cr2O7 dinuclear clusters have been grown on Au(111) and unambiguously identified by scanning tunneling microscopy and theoretical calculations. Upon cycled redox treatments, the two kinds of oxide nanostructures can be reversibly transformed. It is interesting to note that both Cr oxides do not exist in bulk but need to be stabilized by the metal surface and the specific environment. Our results suggest that both redox atmosphere and interface confinement effects can be used to construct an oxide nanostructure with the specific chemical state and structure.
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Affiliation(s)
- Zhiyu Yi
- State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Le Lin
- State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yuan Chang
- Key Laboratory of Material Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116024, China
| | - Xuda Luo
- State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junfeng Gao
- Key Laboratory of Material Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116024, China
| | - Rentao Mu
- State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Yanxiao Ning
- State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Qiang Fu
- State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xinhe Bao
- State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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7
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Sainju R, Rathnayake D, Tan H, Bollas G, Dongare AM, Suib SL, Zhu Y. In Situ Studies of Single-Nanoparticle-Level Nickel Thermal Oxidation: From Early Oxide Nucleation to Diffusion-Balanced Oxide Thickening. ACS NANO 2022; 16:6468-6479. [PMID: 35413193 DOI: 10.1021/acsnano.2c00742] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
High-temperature oxidation mechanisms of metallic nanoparticles have been extensively investigated; however, it is challenging to determine whether the kinetic modeling is applicable at the nanoscale and how the differences in nanoparticle size influence the oxidation mechanisms. In this work, we study thermal oxidation of pristine Ni nanoparticles ranging from 4 to 50 nm in 1 bar 1%O2/N2 at 600 °C using in situ gas-cell environmental transmission electron microscopy. Real-space in situ oxidation videos revealed an unexpected nanoparticle surface refacetting before oxidation and a strong Ni nanoparticle size dependence, leading to distinct structural development during the oxidation and different final NiO morphology. By quantifying the NiO thickness/volume change in real space, individual nanoparticle-level oxidation kinetics was established and directly correlated with nanoparticle microstructural evolution with specified fast and slow oxidation directions. Thus, for the size-dependent Ni nanoparticle oxidation, we propose a unified oxidation theory with a two-stage oxidation process: stage 1: dominated by the early NiO nucleation (Avrami-Erofeev model) and stage 2: the Wagner diffusion-balanced NiO shell thickening (Wanger model). In particular, to what extent the oxidation would proceed into stage 2 dictates the final NiO morphology, which depends on the Ni starting radius with respect to the critical thickness under given oxidation conditions. The overall oxidation duration is controlled by both the diffusivity of Ni2+ in NiO and the Ni in Ni self-diffusion. We also compare the single-particle kinetic curve with the collective one and discuss the effects of nanoparticle size differences on kinetic model analysis.
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8
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Li Y, Zhang Y, Qian K, Huang W. Metal–Support Interactions in Metal/Oxide Catalysts and Oxide–Metal Interactions in Oxide/Metal Inverse Catalysts. ACS Catal 2022. [DOI: 10.1021/acscatal.1c04854] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Yangyang Li
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
- School of Pharmacy, Anhui University of Chinese Medicine, Anhui Academy of Chinese Medicine, Hefei 230012, China
| | - Yunshang Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Kun Qian
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
| | - Weixin Huang
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
- Dalian National Laboratory for Clean Energy, Dalian 116023, China
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9
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Zhao S, Lin L, Huang W, Zhang R, Wang D, Mu R, Fu Q, Bao X. Design of Lewis Pairs via Interface Engineering of Oxide-Metal Composite Catalyst for Water Activation. J Phys Chem Lett 2021; 12:1443-1452. [PMID: 33523659 DOI: 10.1021/acs.jpclett.0c03760] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The rational design and controlled construction of active centers remain grand challenges in heterogeneous catalysis, in particular for oxide catalysts with complex surface and interface structures. This work describes a facile way in the design of highly active Ni-O Lewis pairs for water activation where Ni and O sites act as Lewis acid and base, respectively. Surface science experiments indicate that dissociative adsorption of water occurs at edges of NiOx nanoislands grown on Au(111) and NiOx-Ni interfaces formed by further depositing metallic Ni layers along the edges of NiOx nanoislands. Enhanced activity of Ni-O Lewis pairs at the NiOx-Ni interface has been demonstrated by theoretical calculations, which are attributed to the higher Lewis acidity of metallic Ni sites and synergy of the metal and oxide components. Moreover, proton can migrate away from the NiOx-Ni interface and refresh the O base sites, leading to further hydroxylation of the neighboring Ni acid sites.
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Affiliation(s)
- Siqin Zhao
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Le Lin
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Wugen Huang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rankun Zhang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Zhang Dayu School of Chemistry, Dalian University of Technology, Dalian 116024, China
| | - Dongqing Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rentao Mu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Qiang Fu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xinhe Bao
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
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10
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Abstract
Abstract
Scanning tunneling microscopy (STM) has gained increasing attention in the field of electrocatalysis due to its ability to reveal electrocatalyst surface structures down to the atomic level in either ultra-high-vacuum (UHV) or harsh electrochemical conditions. The detailed knowledge of surface structures, surface electronic structures, surface active sites as well as the interaction between surface adsorbates and electrocatalysts is highly beneficial in the study of electrocatalytic mechanisms and for the rational design of electrocatalysts. Based on this, this review will discuss the application of STM in the characterization of electrocatalyst surfaces and the investigation of electrochemical interfaces between electrocatalyst surfaces and reactants. Based on different operating conditions, UHV-STM and STM in electrochemical environments (EC-STM) are discussed separately. This review will also present emerging techniques including high-speed EC-STM, scanning noise microscopy and tip-enhanced Raman spectroscopy.
Graphic Abstract
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11
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Merte LR, Olsson PAT, Shipilin M, Gustafson J, Bertram F, Zhang C, Grönbeck H, Lundgren E. Structure of two-dimensional Fe 3O 4. J Chem Phys 2020; 152:114705. [PMID: 32199440 DOI: 10.1063/1.5142558] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
We have investigated the structure of an ultrathin iron oxide phase grown on Ag(100) using surface x-ray diffraction in combination with Hubbard-corrected density functional theory (DFT+U) calculations. The film exhibits a novel structure composed of one close-packed layer of octahedrally coordinated Fe2+ sandwiched between two close-packed layers of tetrahedrally coordinated Fe3+ and an overall stoichiometry of Fe3O4. As the structure is distinct from bulk iron oxide phases and the coupling with the silver substrate is weak, we propose that the phase should be classified as a metastable two-dimensional oxide. The chemical and physical properties are potentially interesting, thanks to the predicted charge ordering between atomic layers, and analogy with bulk ferrite spinels suggests the possibility of synthesis of a whole class of two-dimensional ternary oxides with varying electronic, optical, and chemical properties.
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Affiliation(s)
- Lindsay R Merte
- Materials Science and Applied Mathematics, Malmö University, 20506 Malmö, Sweden
| | - Pär A T Olsson
- Materials Science and Applied Mathematics, Malmö University, 20506 Malmö, Sweden
| | - Mikhail Shipilin
- Department of Physics, Stockholm University, AlbaNova University Center, 10691 Stockholm, Sweden
| | - Johan Gustafson
- Division of Synchrotron Radiation Research, Lund University, 22100 Lund, Sweden
| | | | - Chu Zhang
- Division of Synchrotron Radiation Research, Lund University, 22100 Lund, Sweden
| | - Henrik Grönbeck
- Department of Physics and Competence Centre for Catalysis, Chalmers University of Technology, 41296 Göteborg, Sweden
| | - Edvin Lundgren
- Division of Synchrotron Radiation Research, Lund University, 22100 Lund, Sweden
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12
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Jiang Y, Zhu Y, Zhou D, Jiang Z, Si N, Stacchiola D, Niu T. Reversible oxidation and reduction of gold-supported iron oxide islands at room temperature. J Chem Phys 2020; 152:074710. [PMID: 32087652 DOI: 10.1063/1.5136279] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Monolayer iron oxides grown on metal substrates have widely been used as model systems in heterogeneous catalysis. By means of ambient-pressure scanning tunneling microscopy (AP-STM), we studied the in situ oxidation and reduction of FeO(111) grown on Au(111) by oxygen (O2) and carbon monoxide (CO), respectively. Oxygen dislocation lines present on FeO islands are highly active for O2 dissociation. X-ray photoelectron spectroscopy measurements distinctly reveal the reversible oxidation and reduction of FeO islands after sequential exposure to O2 and CO. Our AP-STM results show that excess O atoms can be further incorporated on dislocation lines and react with CO, whereas the CO is not strong enough to reduce the FeO supported on Au(111) that is essential to retain the activity of oxygen dislocation lines.
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Affiliation(s)
- Yixuan Jiang
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, No. 200, Xiaolingwei 210094, China
| | - Yaguang Zhu
- Center for Functional Nanomaterials, Brookhaven National Laboratory, P.O. Box 5000, Upton, New York 11973-5000, USA
| | - Dechun Zhou
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, No. 200, Xiaolingwei 210094, China
| | - Zhao Jiang
- Department of Chemical Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Nan Si
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, No. 200, Xiaolingwei 210094, China
| | - Dario Stacchiola
- Center for Functional Nanomaterials, Brookhaven National Laboratory, P.O. Box 5000, Upton, New York 11973-5000, USA
| | - Tianchao Niu
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, No. 200, Xiaolingwei 210094, China
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