1
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Christopoulou G, Di Paola C, Elzinga FE, Jallat A, Muñoz Ramo D, Krompiec M. Quantum hardware calculations of the activation and dissociation of nitrogen on iron clusters and surfaces. Phys Chem Chem Phys 2024; 26:5895-5906. [PMID: 38315092 DOI: 10.1039/d3cp05167f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Catalytic processes are the cornerstone of chemical industry, and catalytic conversion of nitrogen to ammonia remains one of the largest industrial processes implemented. Rational design of catalysts and catalytic reactions largely depends on approximate computational chemistry methods, such as density functional theory, which, however, suffer from limited accuracy, especially for strongly-correlated materials. Rigorous ab initio methods which account for static and dynamic electron correlation, while arbitrarily accurate for small systems, are generally too expensive to be applied to modelling of catalytic cycles, due to prohibitive time and space computational complexity with respect to the size of the active space. Recent advances in quantum computing give hope for enabling access to accurate ab initio methods at scale. Herein, we present a prototype hybrid quantum-classical workflow for modeling chemical reactions on surfaces, applied to proof-of-concept models of activation and dissociation of nitrogen on small Fe clusters and a single-layer (221) iron surface. First, we determined the structures of species present in the catalytic cycle at DFT level and studied their electronic structure using CASSCF. We show that it is possible to decouple the half-filled Fe-3d band from the Fe-N and N-N bond orbitals, thereby reducing the active space significantly. Subsequently, we translated the CASSCF wavefunctions into corresponding qubit quantum states, using the Adaptive Variational Quantum Eigensolver, and estimated their energies using a state vector simulator, H1-1E quantum emulator and (for selected systems) H1-1 quantum computer. We demonstrated that if a sufficiently small active orbital space is chosen, ground state energies obtained with classical methods and with the quantum computer are in reasonable agreement. We argue that once quantum computing methods are scaled up so that larger active spaces are accessible, they can offer a tremendous practical advantage to the computational catalysis community.
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Affiliation(s)
| | - Cono Di Paola
- Quantinuum, Terrington House, 13-15 Hills Road, CB2 1NL, Cambridge, UK.
| | | | | | - David Muñoz Ramo
- Quantinuum, Terrington House, 13-15 Hills Road, CB2 1NL, Cambridge, UK.
| | - Michal Krompiec
- Quantinuum, Terrington House, 13-15 Hills Road, CB2 1NL, Cambridge, UK.
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2
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Koroteev YM, Silkin IV, Silkin VM, Chulkov EV. Quantum-Size Effects in Ultra-Thin Gold Films on Pt(111) Surface. MATERIALS (BASEL, SWITZERLAND) 2023; 17:63. [PMID: 38203917 PMCID: PMC10779727 DOI: 10.3390/ma17010063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 12/15/2023] [Accepted: 12/19/2023] [Indexed: 01/12/2024]
Abstract
We calculate, within the density-functional theory, the atomic and electronic structure of the clean Pt(111) and Au(111) surfaces and the nML-Au/Pt(111) systems with n varying from one to three. The effect of the spin-orbital interaction was taken into account. Several new electronic states with strong localization in the surface region were found and discussed in the case of clean surfaces. The Au adlayers introduce numerous quantum well states in the energy regions corresponding to the projected bulk band continuum of Au(111). Moreover, the presence of states resembling the true Au(111) surface states can be detected at n = 2 and 3. The Au/Pd interface states are found as well. In nML-Au/Pt(111), the calculated work function presents a small variation with a variation of the number of the Au atomic layer. Nevertheless, the effect is significantly smaller in comparison to the s-p metals.
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Affiliation(s)
- Yury M. Koroteev
- Institute of Strength Physics and Materials Science, Siberian Branch of Russian Academy of Sciences, 634055 Tomsk, Russia
- Laboratory of Electronic and Spin Structure of Nanosystems, Saint Petersburg State University, 198504 Saint Petersburg, Russia
| | - Igor V. Silkin
- Faculty of Physics, Tomsk State University, 634050 Tomsk, Russia
| | - Vyacheslav M. Silkin
- Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Ciencias Químicas, Universidad del País Vasco (UPV-EHU), Apdo. 1072, 20080 San Sebastián, Spain
- Donostia International Physics Center (DIPC), P. Manuel Lardizabal 4, 20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Pl. Euskadi 5, 48009 Bilbao, Spain
| | - Evgueni V. Chulkov
- Laboratory of Electronic and Spin Structure of Nanosystems, Saint Petersburg State University, 198504 Saint Petersburg, Russia
- Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Ciencias Químicas, Universidad del País Vasco (UPV-EHU), Apdo. 1072, 20080 San Sebastián, Spain
- Donostia International Physics Center (DIPC), P. Manuel Lardizabal 4, 20018 San Sebastián, Spain
- Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, P. Manuel Lardizabal 5, 20018 San Sebastián, Spain
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3
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Altenburger B, Andersson C, Levin S, Westerlund F, Fritzsche J, Langhammer C. Label-Free Imaging of Catalytic H 2O 2 Decomposition on Single Colloidal Pt Nanoparticles Using Nanofluidic Scattering Microscopy. ACS NANO 2023; 17:21030-21043. [PMID: 37847543 PMCID: PMC10655234 DOI: 10.1021/acsnano.3c03977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 10/09/2023] [Indexed: 10/18/2023]
Abstract
Single-particle catalysis aims at determining factors that dictate the nanoparticle activity and selectivity. Existing methods often use fluorescent model reactions at low reactant concentrations, operate at low pressures, or rely on plasmonic enhancement effects. Hence, methods to measure single-nanoparticle activity under technically relevant conditions and without fluorescence or other enhancement mechanisms are still lacking. Here, we introduce nanofluidic scattering microscopy of catalytic reactions on single colloidal nanoparticles trapped inside nanofluidic channels to fill this gap. By detecting minuscule refractive index changes in a liquid flushed trough a nanochannel, we demonstrate that local H2O2 concentration changes in water can be accurately measured. Applying this principle, we analyze the H2O2 concentration profiles adjacent to single colloidal Pt nanoparticles during catalytic H2O2 decomposition into O2 and H2O and derive the particles' individual turnover frequencies from the growth rate of the O2 gas bubbles formed in their respective nanochannel during reaction.
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Affiliation(s)
- Björn Altenburger
- Department
of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Carl Andersson
- Department
of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Sune Levin
- Department
of Life Sciences, Chalmers University of
Technology, SE-412 96 Gothenburg, Sweden
| | - Fredrik Westerlund
- Department
of Life Sciences, Chalmers University of
Technology, SE-412 96 Gothenburg, Sweden
| | - Joachim Fritzsche
- Department
of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Christoph Langhammer
- Department
of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
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4
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Kaiser S, Plansky J, Krinninger M, Shavorskiy A, Zhu S, Heiz U, Esch F, Lechner BAJ. Does Cluster Encapsulation Inhibit Sintering? Stabilization of Size-Selected Pt Clusters on Fe 3O 4(001) by SMSI. ACS Catal 2023; 13:6203-6213. [PMID: 37180966 PMCID: PMC10167661 DOI: 10.1021/acscatal.3c00448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/08/2023] [Indexed: 05/16/2023]
Abstract
The metastability of supported metal nanoparticles limits their application in heterogeneous catalysis at elevated temperatures due to their tendency to sinter. One strategy to overcome these thermodynamic limits on reducible oxide supports is encapsulation via strong metal-support interaction (SMSI). While annealing-induced encapsulation is a well-explored phenomenon for extended nanoparticles, it is as yet unknown whether the same mechanisms hold for subnanometer clusters, where concomitant sintering and alloying might play a significant role. In this article, we explore the encapsulation and stability of size-selected Pt5, Pt10, and Pt19 clusters deposited on Fe3O4(001). In a multimodal approach using temperature-programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), and scanning tunneling microscopy (STM), we demonstrate that SMSI indeed leads to the formation of a defective, FeO-like conglomerate encapsulating the clusters. By stepwise annealing up to 1023 K, we observe the succession of encapsulation, cluster coalescence, and Ostwald ripening, resulting in square-shaped crystalline Pt particles, independent of the initial cluster size. The respective sintering onset temperatures scale with the cluster footprint and thus size. Remarkably, while small encapsulated clusters can still diffuse as a whole, atom detachment and thus Ostwald ripening are successfully suppressed up to 823 K, i.e., 200 K above the Hüttig temperature that indicates the thermodynamic stability limit.
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Affiliation(s)
- Sebastian Kaiser
- Chair
of Physical Chemistry and Catalysis Research Center, Department of
Chemistry, School of Natural Sciences, Technical
University of Munich, 85748 Garching, Germany
| | - Johanna Plansky
- Functional
Nanomaterials Group and Catalysis Research Center, Department of Chemistry,
School of Natural Sciences, Technical University
of Munich, 85748 Garching, Germany
| | - Matthias Krinninger
- Functional
Nanomaterials Group and Catalysis Research Center, Department of Chemistry,
School of Natural Sciences, Technical University
of Munich, 85748 Garching, Germany
| | | | - Suyun Zhu
- MAX
IV Laboratory, Lund University, Lund 221 00, Sweden
| | - Ueli Heiz
- Chair
of Physical Chemistry and Catalysis Research Center, Department of
Chemistry, School of Natural Sciences, Technical
University of Munich, 85748 Garching, Germany
| | - Friedrich Esch
- Chair
of Physical Chemistry and Catalysis Research Center, Department of
Chemistry, School of Natural Sciences, Technical
University of Munich, 85748 Garching, Germany
| | - Barbara A. J. Lechner
- Functional
Nanomaterials Group and Catalysis Research Center, Department of Chemistry,
School of Natural Sciences, Technical University
of Munich, 85748 Garching, Germany
- Institute
for Advanced Study, Technical University
of Munich, Lichtenbergstraße
2a, 85748 Garching, Germany
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5
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Balciunas D, Plausinaitis D, Ratautaite V, Ramanaviciene A, Ramanavicius A. Towards electrochemical surface plasmon resonance sensor based on the molecularly imprinted polypyrrole for glyphosate sensing. Talanta 2022; 241:123252. [PMID: 35121544 DOI: 10.1016/j.talanta.2022.123252] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 12/24/2021] [Accepted: 01/19/2022] [Indexed: 12/16/2022]
Abstract
In this research the molecular imprinting technology was applied for the formation of glyphosate-sensitive layer. The glyphosate imprinted conducting polymer polypyrrole (MIPpy) was deposited on a gold chip/electrode and used as an electrochemical surface plasmon resonance (ESPR) sensor. The results described in this study disclose some restrictions and challenges, which arise during the development of glyphosate ESPR sensor based on the molecularly imprinted polymer development stage. It was demonstrated, that glyphosate could significantly affect the electrochemical deposition process of molecularly imprinted polymer on the electrode. The results of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and surface plasmon resonance (SPR) have demonstrated that glyphosate molecules tend to interact with bare gold electrode and thus hinder the polypyrrole deposition. As a possible solution, the formation of a self-assembled monolayer (SAM) of 11-(1H-Pyrrol-1-yl)undecane-1-thiol (PUT) before electrochemical deposition of MIPpy and NIPpy was applied. Dissociation constant (KD) and free energy of Gibbs (ΔG0) values of glyphosate on MIPpy and Ppy without glyphosate imprints (NIPpy) were calculated. For the interaction of glyphosate with MIPpy the KD was determined as 38.18 ± 2.33⋅10-5 and ΔG0 as -19.51 ± 0.15 kJ/mol.
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Affiliation(s)
- Domas Balciunas
- Department of Physical Chemistry, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT, 03225, Vilnius, Lithuania
| | - Deivis Plausinaitis
- Department of Physical Chemistry, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT, 03225, Vilnius, Lithuania
| | - Vilma Ratautaite
- Department of Physical Chemistry, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT, 03225, Vilnius, Lithuania; Nanotechnology Laboratory, Department of Functional Materials and Electronics, Center for Physical Sciences and Technology (FTMC), Saulėtekio av. 3, LT, 10257, Vilnius, Lithuania
| | - Almira Ramanaviciene
- NanoTechnas - Center for Nanotechnology and Material Science, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT, 03225, Vilnius, Lithuania
| | - Arunas Ramanavicius
- Department of Physical Chemistry, Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT, 03225, Vilnius, Lithuania; Nanotechnology Laboratory, Department of Functional Materials and Electronics, Center for Physical Sciences and Technology (FTMC), Saulėtekio av. 3, LT, 10257, Vilnius, Lithuania.
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6
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Soliman AIA, Sayed M, Elshanawany MM, Younis O, Ahmed M, Kamal El-Dean AM, Abdel-Wahab AMA, Wachtveitl J, Braun M, Fatehi P, Tolba MS. Base-Free Synthesis and Photophysical Properties of New Schiff Bases Containing Indole Moiety. ACS OMEGA 2022; 7:10178-10186. [PMID: 35382296 PMCID: PMC8973100 DOI: 10.1021/acsomega.1c06636] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/17/2022] [Indexed: 05/04/2023]
Abstract
Schiff bases represent an essential class in organic chemistry with antitumor, antiviral, antifungal, and antibacterial activities. The synthesis of Schiff bases requires the presence of an organic base as a catalyst such as piperidine. Base-free synthesis of organic compounds using a heterogeneous catalyst has recently attracted more interest due to the facile procedure, high yield, and reusability of the used catalyst. Herein, we present a comparative study to synthesize new Schiff bases containing indole moieties using piperidine as an organic base catalyst and Au@TiO2 as a heterogeneous catalyst. In both methods, the products were isolated in high yields and fully characterized using different spectral analysis techniques. The catalyst was reusable four times, and the activity was slightly decreased. The presence of Au increases the number of acidic sites of TiO2, resulting in C=O polarization. Yields of the prepared Schiff bases in the presence of Au@TiO2 and piperidine were comparable. However, Au@TiO2 is an easily separable and recyclable catalyst, which would facilitate the synthesis of organic compounds without applying any hazardous materials. Furthermore, the luminescence behavior of the synthesized Schiff bases exhibited spectral shape dependence on the substituent group. Interestingly, the compounds also displayed deep-blue fluorescence with Commission Internationale de l'Éclairage (CIE) coordinates of y < 0.1. Thus, these materials may contribute to decreasing the energy consumption of the emitting devices.
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Affiliation(s)
- Ahmed I. A. Soliman
- Chemistry
Department, Faculty of Science, Assiut University, Assiut 71516, Egypt
- Chemical
Engineering Department, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada
| | - Mostafa Sayed
- Chemistry
Department, Faculty of Science, New Valley
University, El-Kharga 72511, Egypt
- Hefei
National Laboratory for Physical Sciences at the Microscale, Department
of Chemistry, University of Science and
Technology of China, Tai Hu Road, Hefei 230026, China
| | - Mahmoud M. Elshanawany
- Institute
of Physical and Theoretical Chemistry, Goethe
University, 60438 Frankfurt am Main, Germany
| | - Osama Younis
- Chemistry
Department, Faculty of Science, New Valley
University, El-Kharga 72511, Egypt
| | - Mostafa Ahmed
- Chemistry
Department, Faculty of Science, New Valley
University, El-Kharga 72511, Egypt
| | | | | | - Josef Wachtveitl
- Institute
of Physical and Theoretical Chemistry, Goethe
University, 60438 Frankfurt am Main, Germany
| | - Markus Braun
- Institute
of Physical and Theoretical Chemistry, Goethe
University, 60438 Frankfurt am Main, Germany
| | - Pedram Fatehi
- Chemical
Engineering Department, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada
| | - Mahmoud S. Tolba
- Chemistry
Department, Faculty of Science, New Valley
University, El-Kharga 72511, Egypt
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7
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First-Principles Study of Pt-Based Bifunctional Oxygen Evolution & Reduction Electrocatalyst: Interplay of Strain and Ligand Effects. ENERGIES 2021. [DOI: 10.3390/en14227814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We examined the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) of Pt-based Pt3M/Pt nanoalloy catalysts (where M represents a 3d transition metal) for bifunctional electrocatalysts using spin-polarized density functional theory calculations. First, the stability of the Pt3M/Pt catalyst was investigated by calculating the bulk formation energy and surface separation energy. Using the calculated adsorption energies for the OER/ORR intermediates in the modeled catalysts, we predicted the OER/ORR overpotentials and potential limiting steps for each catalyst. The origins of the enhanced catalytic reactivity in Pt3M/Pt catalysts caused by strain and ligand effects are explained separately. In addition, compared to Pt(111), the OER and ORR activities in a Pt3Ni/Ptskin catalyst with a Pt skin layer were increased by 13.7% and 18.4%, respectively, due to the strain and ligand effects. It was confirmed that compressive strain and ligand effects are key factors in improving the catalytic performance of OER/ORR bifunctional catalysts.
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8
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Abstract
Enzymes have catalytic turnovers. The field of nanozyme endeavors to engineer nanomaterials as enzyme mimics. However, a discrepancy in the definition of "nanozyme concentration" has led to an unrealistic calculation of nanozyme catalytic turnovers. To date, most of the reported works have considered either the atomic concentration or nanoparticle (NP) concentration as nanozyme concentration. These assumptions can lead to a significant under- or overestimation of the catalytic activity of nanozymes. In this article, we review some classic nanozymes including Fe3O4, CeO2, and gold nanoparticles (AuNPs) with a focus on the reported catalytic activities. We argue that only the surface atoms should be considered as nanozyme active sites, and then the turnover numbers and rates were recalculated based on the surface atoms. According to the calculations, the catalytic turnover of peroxidase Fe3O4 NPs is validated. AuNPs are self-limited when performing glucose-oxidase like activity, but they are also true catalysts. For CeO2 NPs, a self-limited behavior is observed for both oxidase- and phosphatase-like activities due to the adsorption of reaction products. Moreover, the catalytic activity of single-atom nanozymes is discussed. Finally, a few suggestions for future research are proposed.
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Affiliation(s)
- Mohamad Zandieh
- Department of Chemistry, Waterloo Institute for Nanotechnology, Waterloo, Ontario N2L 3G1, Canada
| | - Juewen Liu
- Department of Chemistry, Waterloo Institute for Nanotechnology, Waterloo, Ontario N2L 3G1, Canada
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9
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Li WL, Lininger CN, Chen K, Vaissier Welborn V, Rossomme E, Bell AT, Head-Gordon M, Head-Gordon T. Critical Role of Thermal Fluctuations for CO Binding on Electrocatalytic Metal Surfaces. JACS AU 2021; 1:1708-1718. [PMID: 34723274 PMCID: PMC8549055 DOI: 10.1021/jacsau.1c00300] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Indexed: 06/01/2023]
Abstract
This work considers the evaluation of density functional theory (DFT) when comparing against experimental observations of CO binding trends on the strong binding Pt(111) and intermediate binding Cu(111) and for weak binding Ag(111) and Au(111) surfaces important in electrocatalysis. By introducing thermal fluctuations using appropriate statistical mechanical NVT and NPT ensembles, we find that the RPBE and B97M-rV DFT functionals yield qualitatively better metal surface strain trends and CO enthalpies of binding for Cu(111) and Pt(111) than found at 0 K, thereby correcting the overbinding by 0.2 to 0.3 eV to yield better agreement with the enthalpies determined from experiment. The importance of dispersion effects are manifest for the weak CO binding Ag(111) and Au(111) surfaces at finite temperatures in which the RPBE functional does not bind CO at all, while the B97M-rV functional shows that the CO-metal interactions are a mixture of chemisorbed and physisorbed species with binding enthalpies that are within ∼0.05 eV of experiment. Across all M(111) surfaces, we show that the B97M-rV functional consistently predicts the correct atop site preference for all metals due to thermally induced surface distortions that preferentially favor the undercoordinated site. This study demonstrates the need to fully account for finite temperature fluctuations to make contact with the binding enthalpies from surface science experiments and electrocatalysis applications.
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Affiliation(s)
- Wan-Lu Li
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kenneth
S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
| | - Christianna N. Lininger
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kenneth
S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
| | - Kaixuan Chen
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kenneth
S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
| | - Valerie Vaissier Welborn
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kenneth
S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 26067, United States
| | - Elliot Rossomme
- Kenneth
S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
| | - Alexis T. Bell
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
| | - Martin Head-Gordon
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kenneth
S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
| | - Teresa Head-Gordon
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Kenneth
S. Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720, United States
- Department of Chemistry, Department of Chemical
and Biomolecular Engineering, and Department of
Bioengineering, University of California, Berkeley, California 94720, United States
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10
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Paul N, Huang J, Liu C, Lin T, Ouyang C, Liu Z, Chen C, Chen Z, Weng Z, Schwartzkopf M, Roth SV, Müller-Buschbaum P, Paul A. Real-time observation of nucleation and growth of Au on CdSe quantum dot templates. Sci Rep 2021; 11:18777. [PMID: 34548512 PMCID: PMC8455570 DOI: 10.1038/s41598-021-97485-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/20/2021] [Indexed: 11/30/2022] Open
Abstract
Semiconductor quantum dot (QD) arrays can be useful for optical devices such as lasers, solar cells and light-emitting diodes. As the size distribution influences the band-gap, it is worthwhile to investigate QDs prepared using different solvents because each of them could influence the overall morphology differently, depending on the ligand network around individual QDs. Here, we follow the nucleation and growth of gold (Au) on CdSe QD arrays to investigate the influence of surface ligands and thereby realized interparticle distance between QDs on Au growth behaviour. We particularly emphasize on the monolayer stage as the Au decoration on individual QDs is expected at this stage. Therefore, we sputter-deposit Au on each QD array to investigate the morphological evolution in real-time using time-resolved grazing-incidence small-angle X-ray scattering (GISAXS). The growth kinetics - independent of the template - signifies that the observed template-mediated nucleation is limited only to the very first few monolayers. Delicate changes in the Au growth morphology are seen in the immediate steps following the initial replicated decoration of the QD arrays. This is followed by a subsequent clustering and finally a complete Au coverage of the QD arrays.
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Affiliation(s)
- Neelima Paul
- Technische Universität München, Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenbergstr. 1, 85748, Garching, Germany
| | - Junyu Huang
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | - Chang Liu
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | - Taidong Lin
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | - Chenghao Ouyang
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | - Zhaoyu Liu
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | - Chunfeng Chen
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | - Zhongyi Chen
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | - Zhiyin Weng
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China
| | | | - Stephan V Roth
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22603, Hamburg, Germany.,Department of Fiber and Polymer Technology, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44, Stockholm, Sweden
| | - Peter Müller-Buschbaum
- Technische Universität München, Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenbergstr. 1, 85748, Garching, Germany.,Physik-Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Str. 1, 85748, Garching, Germany
| | - Amitesh Paul
- Guangdong Technion-Israel Institute of Technology, Shantou, 515063, Guangdong, China.
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11
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Shih AJ, Arulmozhi N, Koper MTM. Electrocatalysis under Cover: Enhanced Hydrogen Evolution via Defective Graphene-Covered Pt(111). ACS Catal 2021. [DOI: 10.1021/acscatal.1c02145] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Arthur J. Shih
- Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Nakkiran Arulmozhi
- Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Marc T. M. Koper
- Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
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12
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Haid RW, Kluge RM, Liang Y, Bandarenka AS. In Situ Quantification of the Local Electrocatalytic Activity via Electrochemical Scanning Tunneling Microscopy. SMALL METHODS 2021; 5:e2000710. [PMID: 34927879 DOI: 10.1002/smtd.202000710] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/10/2020] [Indexed: 06/14/2023]
Abstract
Identification of catalytically active sites at solid/liquid interfaces under reaction conditions is an essential task to improve the catalyst design for sustainable energy devices. Electrochemical scanning tunneling microscopy (EC-STM) combines the control of the surface reactions with imaging on a nanoscale. When performing EC-STM under reaction conditions, the recorded analytical signal shows higher fluctuations (noise) at active sites compared to non-active sites (noise-EC-STM or n-EC-STM). In the past, this approach has been proven as a valid tool to identify the location of active sites. In this work, the authors show that this method can be extended to obtain quantitative information of the local activity. For the platinum(111) surface under oxygen reduction reaction conditions, a linear relationship between the STM noise level and a measure of reactivity, the turn-over frequency is found. Since it is known that the most active sites for this system are located at concave sites, the method has been applied to quantify the activity at steps. The obtained activity enhancement factors appeared to be in good agreement with the literature. Thus, n-EC-STM is a powerful method not only to in situ identify the location of active sites but also to determine and compare local reactivity.
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Affiliation(s)
- Richard W Haid
- Department of Physics (ECS), Technical University of Munich, James-Franck-Straße 1, Garching, 85748, Germany
| | - Regina M Kluge
- Department of Physics (ECS), Technical University of Munich, James-Franck-Straße 1, Garching, 85748, Germany
| | - Yunchang Liang
- Department of Physics (ECS), Technical University of Munich, James-Franck-Straße 1, Garching, 85748, Germany
| | - Aliaksandr S Bandarenka
- Department of Physics (ECS), Technical University of Munich, James-Franck-Straße 1, Garching, 85748, Germany
- Catalysis Research Center TUM, Ernst-Otto-Fischer-Straße 1, Garching, 85748, Germany
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13
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Lininger CN, Gauthier JA, Li WL, Rossomme E, Welborn VV, Lin Z, Head-Gordon T, Head-Gordon M, Bell AT. Challenges for density functional theory: calculation of CO adsorption on electrocatalytically relevant metals. Phys Chem Chem Phys 2021; 23:9394-9406. [DOI: 10.1039/d0cp03821k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We assess four DFT functionals, RTPSS, RPBE, SCAN and B97M-rV, for surface interactions. We find that B97M-rV predicts the correct site preference for CO binding on Ag and Au while RTPSS performs well for surface relaxations and binding of CO on Pt and Cu.
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Affiliation(s)
- Christianna N. Lininger
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemical and Biomolecular Engineering
| | - Joseph A. Gauthier
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemical and Biomolecular Engineering
| | - Wan-Lu Li
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Kenneth S. Pitzer Center for Theoretical Chemistry
| | - Elliot Rossomme
- Kenneth S. Pitzer Center for Theoretical Chemistry
- Department of Chemistry
- University of California
- Berkeley
- USA
| | - Valerie Vaissier Welborn
- Kenneth S. Pitzer Center for Theoretical Chemistry
- Department of Chemistry
- University of California
- Berkeley
- USA
| | - Zhou Lin
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Kenneth S. Pitzer Center for Theoretical Chemistry
| | - Teresa Head-Gordon
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemical and Biomolecular Engineering
| | - Martin Head-Gordon
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Kenneth S. Pitzer Center for Theoretical Chemistry
| | - Alexis T. Bell
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemical and Biomolecular Engineering
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14
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Piwowar J, Lewera A. Formic acid catalytic electrooxidation on Pt covered by Au adstructures – role of electronic surface properties. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.137099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Streibel V, Choksi TS, Abild-Pedersen F. Predicting metal-metal interactions. I. The influence of strain on nanoparticle and metal adlayer stabilities. J Chem Phys 2020; 152:094701. [PMID: 33480713 DOI: 10.1063/1.5130566] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Strain-engineering of bimetallic nanomaterials is an important design strategy for developing new catalysts. Herein, we introduce an approach for including strain effects into a recently introduced, density functional theory (DFT)-based alloy stability model. The model predicts adsorption site stabilities in nanoparticles and connects these site stabilities with catalytic reactivity and selectivity. Strain-based dependencies will increase the model's accuracy for nanoparticles affected by finite-size effects. In addition to the stability of small nanoparticles, strain also influences the heat of adsorption of epitaxially grown metal-on-metal adlayers. In this respect, we successfully benchmark the strain-including alloy stability model with previous experimentally determined trends in the heats of adsorption of Au and Cu adlayers on Pt (111). For these systems, our model predicts stronger bimetallic interactions in the first monolayer than monometallic interactions in the second monolayer. We explicitly quantify the interplay between destabilizing strain effects and the energy gained by forming new metal-metal bonds. While tensile strain in the first Cu monolayer significantly destabilizes the adsorption strength, compressive strain in the first Au monolayer has a minimal impact on the heat of adsorption. Hence, this study introduces and, by comparison with previous experiments, validates an efficient DFT-based approach for strain-engineering the stability, and, in turn, the catalytic performance, of active sites in bimetallic alloys with atomic level resolution.
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Affiliation(s)
- Verena Streibel
- SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University, 443 Via Ortega, Stanford, California 94305, USA
| | - Tej S Choksi
- SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University, 443 Via Ortega, Stanford, California 94305, USA
| | - Frank Abild-Pedersen
- SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
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16
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Wang W, Wen Z, Hu S, Li Z, Wu X, Zhu J, Shao X. An ultrathin cuprite film on Pt(111) with high reactivity to CO. Chem Commun (Camb) 2019; 55:5825-5828. [PMID: 31041937 DOI: 10.1039/c9cc01002e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A highly ordered copper(i) oxide film grown on a Pt(111) substrate exhibits extremely high reactivity to CO molecules. Systematic scanning tunneling microscopy experiments in combination with density-functional theory calculations demonstrate that the reaction occurs at the peripheries of the Cu2O islands where low-coordinated oxygen atoms are located.
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Affiliation(s)
- Wenyuan Wang
- Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.
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17
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Liang Y, Csoklich C, McLaughlin D, Schneider O, Bandarenka AS. Revealing Active Sites for Hydrogen Evolution at Pt and Pd Atomic Layers on Au Surfaces. ACS APPLIED MATERIALS & INTERFACES 2019; 11:12476-12480. [PMID: 30864772 DOI: 10.1021/acsami.8b22146] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Identification of the most active surface sites is one of the key tasks in the development of new electrocatalytic materials. This is in many cases both time and resource consuming due to methodological difficulties of in situ detection of centers of this kind. In this work, we use the recently developed approach based on the analysis of the tunneling current noise recorded by electrochemical scanning tunneling microscopy (n-ECSTM) to compare the nature of the most active hydrogen evolution catalytic sites in a system consisting of sub-monolayers of platinum on a Au substrate to the one of palladium on Au. Our n-ECSTM measurements performed under reaction conditions show that in striking contrast to Pd islands on gold, where the most active centers are located close to the boundary between Au and palladium atoms, all Pt ad-atoms contribute to the overall activity rather equally at pH 1. Methodological aspects related to the use of n-ECSTM in electrocatalytic research are also discussed.
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Affiliation(s)
- Yunchang Liang
- Physik-Department ECS , Technische Universität München , James-Franck-Str. 1 , 85748 Garching , Germany
| | - Christoph Csoklich
- Physik-Department ECS , Technische Universität München , James-Franck-Str. 1 , 85748 Garching , Germany
| | - David McLaughlin
- Physik-Department ECS , Technische Universität München , James-Franck-Str. 1 , 85748 Garching , Germany
| | - Oliver Schneider
- Institut für Informatik VI , Technische Universität München , Schleißheimer Straße 90a , 85748 Garching , Germany
| | - Aliaksandr S Bandarenka
- Physik-Department ECS , Technische Universität München , James-Franck-Str. 1 , 85748 Garching , Germany
- Nanosystems Initiative Munich (NIM) , Schellingstraße 4 , 80799 Munich , Germany
- Catalysis Research Center TUM , Ernst-Otto-Fischer-Straße 1 , 85748 Garching , Germany
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18
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Modification of a Shockley-Type Surface State on Pt(111) upon Deposition of Gold Thin Layers. MATERIALS 2018; 11:ma11122569. [PMID: 30562975 PMCID: PMC6316031 DOI: 10.3390/ma11122569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 12/12/2018] [Accepted: 12/13/2018] [Indexed: 11/28/2022]
Abstract
We present a first-principles fully-relativistic study of surface and interface states in the n one monolayer (ML) Au/Pt(111) heterostructures. The modification of an unoccupied s−p-type surface state existing on a Pt(111) surface at the surface Brillouin zone center upon deposition of a few atomic Au layers is investigated. In particular, we find that the transformation process of such a surface state upon variation of the Au adlayer thickness crucially depends on the nature of the relevant quantum state in the adsorbate. When the Au adlayer consists of one or two monolayers and this relevant state has energy above the Pt(111) surface state position, the latter shifts downward upon approaching the Au adlayer. As a result, in the 1 ML Au/Pt(111) and 2 ML Au/Pt(111) heterostructures at the equilibrium adlayer position, the Pt-derived surface state experiences strong hybridization with the bulk electronic states and becomes a strong occupied resonance. In contrast, when the number n of atomic layers in the Au films increases to three or more, the Pt(111) surface state shifts upward upon reduction of the distance between the Pt(111) surface and the Au adlayer. At equilibrium, the Pt-derived surface state transforms into an unoccupied quantum-well state of the Au adlayer. This change is explained by the fact that the relevant electronic state in free-standing Au films with n≥3 has lower energy in comparison to the Pt(111) surface state.
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19
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Formation of Surface and Quantum-Well States in Ultra Thin Pt Films on the Au(111) Surface. MATERIALS 2017; 10:ma10121409. [PMID: 29232833 PMCID: PMC5744344 DOI: 10.3390/ma10121409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 12/05/2017] [Accepted: 12/07/2017] [Indexed: 12/22/2022]
Abstract
The electronic structure of the Pt/Au(111) heterostructures with a number of Pt monolayers n ranging from one to three is studied in the density-functional-theory framework. The calculations demonstrate that the deposition of the Pt atomic thin films on gold substrate results in strong modifications of the electronic structure at the surface. In particular, the Au(111) s-p-type Shockley surface state becomes completely unoccupied at deposition of any number of Pt monolayers. The Pt adlayer generates numerous quantum-well states in various energy gaps of Au(111) with strong spatial confinement at the surface. As a result, strong enhancement in the local density of state at the surface Pt atomic layer in comparison with clean Pt surface is obtained. The excess in the density of states has maximal magnitude in the case of one monolayer Pt adlayer and gradually reduces with increasing number of Pt atomic layers. The spin-orbit coupling produces strong modification of the energy dispersion of the electronic states generated by the Pt adlayer and gives rise to certain quantum states with a characteristic Dirac-cone shape.
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20
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Mishra P, Qi ZK, Oka H, Nakamura K, Komeda T. Spatially Resolved Magnetic Anisotropy of Cobalt Nanostructures on the Au(111) Surface. NANO LETTERS 2017; 17:5843-5847. [PMID: 28806089 DOI: 10.1021/acs.nanolett.7b03114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Understanding the origin of perpendicular magnetic anisotropy in surface-supported nanoclusters is crucial for fundamental research as well as data storage applications. Here, we investigate the perpendicular magnetic anisotropy energy (MAE) of bilayer cobalt islands on Au(111) substrate using spin-polarized scanning tunneling microscopy at 4.6 K and first-principles theoretical calculations. Au(111) substrate serves as an excellent model system to study the effect of nucleation site and stacking sequence on MAE. Our measurements reveal that the MAE of bilayer islands depends strongly on the crystallographic stacking of the two Co layers and nucleation of the third layer. Moreover, the MAE of Co atoms on Au(111) is enhanced by a factor of 1.75 as compared to that reported on Cu(111). Our first-principles calculations attribute this enhancement to the large spin-orbit coupling of the Au atoms. Our results highlight the strong impact of nanometer-scale structural changes in Co islands on MAE and emphasize the importance of spatially resolved measurements for the magnetic characterization of surface-supported nanostructures.
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Affiliation(s)
- Puneet Mishra
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University , Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Zhi Kun Qi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University , Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Hirofumi Oka
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University , Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Kohji Nakamura
- Department of Physics Engineering, Mie University , Tsu, Mie 514-8507, Japan
| | - Tadahiro Komeda
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University , Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
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21
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Electron transfer kinetics of the ferrous/ferric redox system on the platinum deposits on gold. J Electroanal Chem (Lausanne) 2017. [DOI: 10.1016/j.jelechem.2016.11.054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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22
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Wong RJ, Scott J, Kappen P, Low GKC, Hart JN, Amal R. Enhancing bimetallic synergy with light: the effect of UV light pre-treatment on catalytic oxygen activation by bimetallic Au–Pt nanoparticles on a TiO2 support. Catal Sci Technol 2017. [DOI: 10.1039/c7cy01326d] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
UV pre-illumination-enhanced bimetallic synergy work-function-driven electron transfer pathway. Au; Pt; oxygen; electron.
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Affiliation(s)
- Roong Jien Wong
- Particles and Catalysis Research Group
- School of Chemical Engineering
- The University of New South Wales
- Sydney
- Australia
| | - Jason Scott
- Particles and Catalysis Research Group
- School of Chemical Engineering
- The University of New South Wales
- Sydney
- Australia
| | | | - Gary K.-C. Low
- Particles and Catalysis Research Group
- School of Chemical Engineering
- The University of New South Wales
- Sydney
- Australia
| | - Judy N. Hart
- School of Materials Science and Engineering
- The University of New South Wales
- Sydney
- Australia
| | - Rose Amal
- Particles and Catalysis Research Group
- School of Chemical Engineering
- The University of New South Wales
- Sydney
- Australia
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23
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Streller F, Qi Y, Yang J, Mangolini F, Rappe AM, Carpick RW. Valence Band Control of Metal Silicide Films via Stoichiometry. J Phys Chem Lett 2016; 7:2573-2578. [PMID: 27322019 DOI: 10.1021/acs.jpclett.6b00799] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The unique electronic and mechanical properties of metal silicide films render them interesting for advanced materials in plasmonic devices, batteries, field-emitters, thermoelectric devices, transistors, and nanoelectromechanical switches. However, enabling their use requires precisely controlling their electronic structure. Using platinum silicide (PtxSi) as a model silicide, we demonstrate that the electronic structure of PtxSi thin films (1 ≤ x ≤ 3) can be tuned between metallic and semimetallic by changing the stoichiometry. Increasing the silicon content in PtxSi decreases the carrier density according to valence band X-ray photoelectron spectroscopy and theoretical density of states (DOS) calculations. Among all PtxSi phases, Pt3Si offers the highest DOS due to the modest shift of the Pt5d manifold away from the Fermi edge by only 0.5 eV compared to Pt, rendering it promising for applications. These results, demonstrating tunability of the electronic structure of thin metal silicide films, suggest that metal silicides can be designed to achieve application-specific electronic properties.
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Affiliation(s)
- Frank Streller
- Department of Materials Science and Engineering, ‡Makineni Theoretical Laboratories, Department of Chemistry, and ¶Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
| | - Yubo Qi
- Department of Materials Science and Engineering, ‡Makineni Theoretical Laboratories, Department of Chemistry, and ¶Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
| | - Jing Yang
- Department of Materials Science and Engineering, ‡Makineni Theoretical Laboratories, Department of Chemistry, and ¶Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
| | - Filippo Mangolini
- Department of Materials Science and Engineering, ‡Makineni Theoretical Laboratories, Department of Chemistry, and ¶Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
| | - Andrew M Rappe
- Department of Materials Science and Engineering, ‡Makineni Theoretical Laboratories, Department of Chemistry, and ¶Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
| | - Robert W Carpick
- Department of Materials Science and Engineering, ‡Makineni Theoretical Laboratories, Department of Chemistry, and ¶Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
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24
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Griffin MB, Ferguson GA, Ruddy DA, Biddy MJ, Beckham GT, Schaidle JA. Role of the Support and Reaction Conditions on the Vapor-Phase Deoxygenation of m-Cresol over Pt/C and Pt/TiO2 Catalysts. ACS Catal 2016. [DOI: 10.1021/acscatal.5b02868] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Michael B. Griffin
- National Bioenergy Center, National Renewable Energy Laboratory, 15013
Denver West Parkway, Golden, Colorado 80401, United States
| | - Glen A. Ferguson
- National Bioenergy Center, National Renewable Energy Laboratory, 15013
Denver West Parkway, Golden, Colorado 80401, United States
| | - Daniel A. Ruddy
- National Bioenergy Center, National Renewable Energy Laboratory, 15013
Denver West Parkway, Golden, Colorado 80401, United States
| | - Mary J. Biddy
- National Bioenergy Center, National Renewable Energy Laboratory, 15013
Denver West Parkway, Golden, Colorado 80401, United States
| | - Gregg T. Beckham
- National Bioenergy Center, National Renewable Energy Laboratory, 15013
Denver West Parkway, Golden, Colorado 80401, United States
| | - Joshua A. Schaidle
- National Bioenergy Center, National Renewable Energy Laboratory, 15013
Denver West Parkway, Golden, Colorado 80401, United States
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