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Qian C, Hedman D, Li P, Kim SY, Ding F. The Reconstruction of Pt(001) Surface and the Shell-Like Reconstruction of the Vicinal Pt(001) Surfaces Revealed by Neural Network Potential. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2404274. [PMID: 38966895 DOI: 10.1002/smll.202404274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Revised: 06/18/2024] [Indexed: 07/06/2024]
Abstract
In this work, a highly accurate neural network potential (NNP) is presented, named PtNNP, and the exploration of the reconstruction of the Pt(001) surface and its vicinal surfaces with it. Contrary to the most accepted understanding of the Pt(001) surface reconstruction, the study reveals that the main driving force behind Pt(001) quasi-hexagonal reconstruction is not the surface stress relaxation but the increased coordination number of the surface atoms resulting in stronger intralayer binding in the reconstructed surface layer. In agreement with experimental observations, the optimized supercell size of the reconstructed Pt(001) surface contains (5 × 20) unit cells. Surprisingly, the reconstruction of the vicinal Pt(001) surfaces leads to a smooth shell-like surface layer covering the whole surface and diminishing sharp step edges.
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Affiliation(s)
- Cheng Qian
- Faculty of Materials Science and Energy Engineering, Shenzhen University of Advanced Technology, Shenzhen, 518055, China
- Institute of Technology for Carbon Neutrality, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Daniel Hedman
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan, 44919, Republic of Korea
| | - Pai Li
- State Key Laboratory of Materials for Integrated Circuits, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Sung Youb Kim
- Department of Mechanical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Feng Ding
- Faculty of Materials Science and Energy Engineering, Shenzhen University of Advanced Technology, Shenzhen, 518055, China
- Institute of Technology for Carbon Neutrality, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
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2
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Vital CA, Buendía F, Beltrán MR. CO oxidation reactions on 3-d single metal atom catalysts/MgO(100). Phys Chem Chem Phys 2024; 26:18173-18181. [PMID: 38899760 DOI: 10.1039/d4cp00160e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
The present work deals with a comprehensive computational theoretical study of the molecular CO and O2 adsorption on 3d single atoms (M/MgO(100)). The study is based on the chemical elements of the 3d row, as they represent an economic advantage compared with the so-called noble metals. The present study has been performed employing density functional theory calculations. Through the representation of the metastable states, we perform a synergetic analysis of the CO oxidation reaction to find trends that suggest the possible use of new candidates such as Ni/MgO(100) or Cu/MgO(100) single-atom catalysts, for this type of redox reaction. We found that Ni and Cu produce energetically viable CO to CO2 reactions. Ni and Cu atoms show the greatest diffusion barrier and are the best candidates due to their low sintering capability. The energetic and electronic properties of the single Cu and Ni atoms on MgO (100) give them the best characteristics to help in the CO oxidation process.
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Affiliation(s)
- C A Vital
- Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apartado Postal 70-360, C.P. 04510, Ciudad de México, Mexico
| | - F Buendía
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore.
| | - M R Beltrán
- Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apartado Postal 70-360, C.P. 04510, Ciudad de México, Mexico
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3
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Inico E, Saetta C, Di Liberto G. Impact of quantum size effects to the band gap of catalytic materials: a computational perspective. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:361501. [PMID: 38830369 DOI: 10.1088/1361-648x/ad53b5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 06/03/2024] [Indexed: 06/05/2024]
Abstract
The evolution of nanotechnology has facilitated the development of catalytic materials with controllable composition and size, reaching the sub-nanometer limit. Nowadays, a viable strategy for tailoring and optimizing the catalytic activity involves controlling the size of the catalyst. This strategy is underpinned by the fact that the properties and reactivity of objects with dimensions on the order of nanometers can differ from those of the corresponding bulk material, due to the emergence of quantum size effects. Quantum size effects have a deep influence on the band gap of semiconducting catalytic materials. Computational studies are valuable for predicting and estimating the impact of quantum size effects. This perspective emphasizes the crucial role of modeling quantum size effects when simulating nanostructured catalytic materials. It provides a comprehensive overview of the fundamental principles governing the physics of quantum confinement in various experimentally observable nanostructures. Furthermore, this work may serve as a tutorial for modeling the electronic gap of simple nanostructures, highlighting that when working at the nanoscale, the finite dimensions of the material lead to an increase of the band gap because of the emergence of quantum confinement. This aspect is sometimes overlooked in computational chemistry studies focused on surfaces and nanostructures.
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Affiliation(s)
- Elisabetta Inico
- Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via R. Cozzi 55, 20125 Milano, Italy
| | - Clara Saetta
- Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via R. Cozzi 55, 20125 Milano, Italy
| | - Giovanni Di Liberto
- Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via R. Cozzi 55, 20125 Milano, Italy
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4
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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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5
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Liao GJ, Hsueh WH, Yen YH, Shih YC, Wang CH, Wang JH, Luo MF. Decomposition of methanol-d 4 on Rh nanoclusters supported by thin-film Al 2O 3/NiAl(100) under near-ambient-pressure conditions. Phys Chem Chem Phys 2024; 26:5059-5069. [PMID: 38258542 DOI: 10.1039/d3cp05303b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The decomposition of methanol-d4 (CD3OD) on Rh nanoclusters grown by the deposition of Rh vapors onto an ordered thin film of Al2O3/NiAl(100) was studied, with various surface-probe techniques and largely under near-ambient-pressure (NAP) conditions. The results showed a superior reactivity of small Rh clusters (diameter < 1.5 nm) exposed to CD3OD at 5 × 10-3-0.1 mbar at 400 K; the gaseous production of CO and D2 from decomposed methanol-d4 per Rh surface site on the small Rh clusters with diameters of ∼1.1 nm was nearly 8 times that on large ones with diameters of ∼3.5 nm. The promotion of reactivity with decreased cluster size under NAP conditions was evidently greater than that under ultrahigh vacuum conditions. Moreover, the concentration of atomic carbon (C*; where * denotes adsorbate)-a key catalyst poisoner-yielded from the dissociation of CO* from dehydrogenated methanol-d4 was significantly smaller on small clusters (diameter < 1.5 nm). The NAP size effect on methanol-d4 decomposition involved the surface hydroxyl (OH*) from the little co-adsorbed water (H2O*) that was dissociated at a probability dependent on the cluster size. H2O* was more likely dissociated into OH* on small Rh clusters, by virtue of their more reactive d-band structure, and the OH* then effectively promoted the O-D cleavage of methanol-d4, as the rate-determining step, and thus the reaction probability; on the other hand, the OH* limited CO* dissociation on small Rh clusters via both adsorbate and lateral effects. These results suggest that the superior properties of small Rh clusters in both reactivity and anti-poisoning would persist and be highly applicable under "real-world" catalysis conditions.
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Affiliation(s)
- Guan-Jr Liao
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan.
| | - Wen-Hao Hsueh
- Department of Chemistry, National Taiwan Normal University, No. 88, Section 4, Ting-Zhou Road, Taipei, Taiwan.
| | - Yu-Hsiang Yen
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan.
| | - Yi-Chan Shih
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan.
| | - Chia-Hsin Wang
- National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan
| | - Jeng-Han Wang
- Department of Chemistry, National Taiwan Normal University, No. 88, Section 4, Ting-Zhou Road, Taipei, Taiwan.
| | - Meng-Fan Luo
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan.
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6
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Liao GJ, Hsueh WH, Yen YH, Shih YC, Wang CH, Wang JH, Luo MF. Decomposition of methanol-d4 on a thin film of Al2O3/NiAl(100) under near-ambient-pressure conditions. J Chem Phys 2023; 158:2887766. [PMID: 37129140 DOI: 10.1063/5.0151135] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 04/17/2023] [Indexed: 05/03/2023] Open
Abstract
We have studied the decomposition of methanol-d4 on thin film Al2O3/NiAl(100) under near-ambient-pressure conditions, with varied surface-probe techniques and calculations based on density-functional theory. Methanol-d4 neither adsorbed nor reacted on Al2O3/NiAl(100) at 400 K under ultrahigh vacuum conditions, whereas they dehydrogenated, largely to methoxy-d3 (CD3O*, * denoting adsorbates) and formaldehyde-d2 (CD2O*), on the surface when the methanol-d4 partial pressure was increased to 10-3 mbar and above. The dehydrogenation was facilitated by hydroxyl (OH* or OD*) from the dissociation of little co-adsorbed water; a small fraction of CD2O* interacted further with OH* (OD*) to form, via intermediate CD2OOH* (CD2OOD*), formic acid (DCOOH* or DCOOD*). A few surface carbonates were also yielded, likely on the defect sites of Al2O3/NiAl(100). The results suggest that alumina not only supports metal clusters but also participates in reactions under realistic catalytic conditions. One may consider accordingly the multiple functions of alumina while designing ideal catalysts.
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Affiliation(s)
- Guan-Jr Liao
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan
| | - Wen-Hao Hsueh
- Department of Chemistry, National Taiwan Normal University, No. 88, Sec. 4, Ting-Zhou Road, Taipei, Taiwan
| | - Yu-Hsiang Yen
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan
| | - Yi-Chan Shih
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan
| | - Chia-Hsin Wang
- National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan
| | - Jeng-Han Wang
- Department of Chemistry, National Taiwan Normal University, No. 88, Sec. 4, Ting-Zhou Road, Taipei, Taiwan
| | - Meng-Fan Luo
- Department of Physics, National Central University, No. 300 Jhongda Road, Jhongli 32054, Taiwan
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7
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Li R, Jiang X, Zhou C, Topsakal M, Nykypanchuk D, Attenkofer K, Stacchiola DJ, Hybertsen MS, Stavitski E, Qu X, Lu D, Liu M. Deciphering phase evolution in complex metal oxide thin films via high-throughput materials synthesis and characterization. NANOTECHNOLOGY 2023; 34:125701. [PMID: 36538812 DOI: 10.1088/1361-6528/acad09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
Discovery of structure-property relationships in thin film alloys of complex metal oxides enabled by high-throughput materials synthesis and characterization facilities is demonstrated here with a case-study. Thin films of binary transition metal oxides (Ti-Zn) are prepared by pulsed laser deposition with continuously varying Ti:Zn ratio, creating combinatorial samples for exploration of the properties of this material family. The atomic structure and electronic properties are probed by spatially resolved techniques including x-ray absorption near edge structures (XANES) and x-ray fluorescence (XRF) at the Ti and Zn K-edge, x-ray diffraction, and spectroscopic ellipsometry. The observed properties as a function of Ti:Zn ratio are resolved into mixtures of five distinguishable phases by deploying multivariate curve resolution analysis on the XANES spectral series, under constraints set by results from the other characterization techniques. First-principles computations based on density function theory connect the observed properties of each distinct phase with structural and spectral characteristics of crystalline polymorphs of Ti-Zn oxide. Continuous tuning of the optical absorption edge as a function of Ti:Zn ratio, including the unusual observation of negative optical bowing, exemplifies a functional property of the film correlated to the phase evolution.
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Affiliation(s)
- Ruoshui Li
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, United States of America
| | - Xuance Jiang
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
- Department of Physics, Stony Brook University, Stony Brook, NY 11794, United States of America
| | - Chenyu Zhou
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Mehmet Topsakal
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Dmytro Nykypanchuk
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Klaus Attenkofer
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Dario J Stacchiola
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Mark S Hybertsen
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Eli Stavitski
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Xiaohui Qu
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Deyu Lu
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
| | - Mingzhao Liu
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, United States of America
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8
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Sakata K, Amemiya K. Time- and Depth-Resolved Chemical State Analysis of the Surface-to-Subsurface Oxidation of Cu by X-ray Absorption Spectroscopy at Near Ambient Pressure. J Phys Chem Lett 2022; 13:9573-9580. [PMID: 36201653 DOI: 10.1021/acs.jpclett.2c02641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Metal surface oxidation is a well-known phenomenon, but the oxidation states of metal surfaces have not been observed in situ and in real time because most techniques obtaining surface chemical states require high-vacuum conditions. Here, we achieved the real-time, in situ observation of the initial stages of surface Cu oxidation using fluorescence-yield wavelength-dispersive X-ray absorption spectroscopy (XAS) in the soft X-ray region at sub-nanometer depth resolution. Further, the XAS data suggest a unique oxidation mechanism: CuO forms on the top surface, and subsequently, Cu2O forms in the subsurface layers (>1 nm from the surface), accompanied by the interdiffusion of Cu from the inner layer and that of Cu2O to the inner layer. The reported technique has applications for the analysis of surface phenomena at ambient pressure, especially oxidation processes, whose understanding is crucial in many fields, from chemistry to structural engineering.
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Affiliation(s)
- Kaoruho Sakata
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki305-0801, Japan
| | - Kenta Amemiya
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki305-0801, Japan
- Department of Materials Structure Science, SOKENDAI (The Graduate University for Advanced Studies), 1-1 Oho, Tsukuba, Ibaraki305-0801, Japan
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9
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Hara Y, Shigetake R, Nakanishi K, Kanamori K, Sakaushi K. Oxide-on-Oxide Porous Electrodes Revealing Superior Reversible Li +-Coupled Electron-Transfer Properties by Unconventional Heterojunction Effects. ACS APPLIED MATERIALS & INTERFACES 2022; 14:35883-35893. [PMID: 35899419 DOI: 10.1021/acsami.2c06297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Internal spacing of electrodes is a key point for controlling electron-transfer (ET)-related phenomena. However, their disordered porous structures often prevent the observation of microscopic effects. It hampers the development of modern electrochemical theories. The development of model porous electrodes therefore provides an ideal platform to discover intriguing fundamental principles of electrode processes. We developed a new synthetic strategy for all-oxide monolithic ruthenium dioxide (RuO2)/antimony-doped tin oxide (ATO) electrodes with a controlled hierarchically porous structure and oxide-oxide heterojunction. The use of the obtained RuO2/ATO electrodes as model electrodes suppressed influences related to different mass diffusion efficiencies between electrodes with heterojunctions of different types. Then, we showed unconventional oxide-oxide heterojunction effects, improving reversible Li+-coupled electron-transfer properties using model electrodes constituted of various nanostructured (nano-) RuO2 on porous ATO. In addition to the superior electrochemical properties of the nano-RuO2/ATO heterojunction, the quasi-two-dimensional (2D) RuO2/ATO heterojunction led to improved specific capacity at a high rate and longer cycle life. We anticipate that this oxide-oxide heterojunction effect and developed all-oxide model porous electrodes can provide a path to develop advanced reversible energy storage devices.
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Affiliation(s)
- Yosuke Hara
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
- Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Rikuo Shigetake
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kazuki Nakanishi
- Institute of Materials and Systems for Sustainability, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
- Institute for Integrated Cell-Material Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kazuyoshi Kanamori
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Ken Sakaushi
- Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
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Abstract
Two-dimensional (2D) ultrathin silica films have the potential to reach technological importance in electronics and catalysis. Several well-defined 2D-silica structures have been synthesized so far. The silica bilayer represents a 2D material with SiO2 stoichiometry. It consists of precisely two layers of tetrahedral [SiO4] building blocks, corner connected via oxygen bridges, thus forming a self-saturated silicon dioxide sheet with a thickness of ∼0.5 nm. Inspired by recent successful preparations and characterizations of these 2D-silica model systems, scientists now can forge novel concepts for realistic systems, particularly by atomic-scale studies with the most powerful and advanced surface science techniques and density functional theory calculations. This Review provides a solid introduction to these recent developments, breakthroughs, and implications on ultrathin 2D-silica films, including their atomic/electronic structures, chemical modifications, atom/molecule adsorptions, and catalytic reactivity properties, which can help to stimulate further investigations and understandings of these fundamentally important 2D materials.
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Affiliation(s)
- Jian-Qiang Zhong
- School of Physics, Hangzhou Normal University, No. 2318, Yuhangtang Road, Hangzhou, 311121 Zhejiang, China
| | - Hans-Joachim Freund
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
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11
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Kovarik S, Robles R, Schlitz R, Seifert TS, Lorente N, Gambardella P, Stepanow S. Electron Paramagnetic Resonance of Alkali Metal Atoms and Dimers on Ultrathin MgO. NANO LETTERS 2022; 22:4176-4181. [PMID: 35512394 DOI: 10.1021/acs.nanolett.2c00980] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Electron paramagnetic resonance (EPR) can provide unique insight into the chemical structure and magnetic properties of dopants in oxide and semiconducting materials that are of interest for applications in electronics, catalysis, and quantum sensing. Here, we demonstrate that EPR in combination with scanning tunneling microscopy (STM) allows for probing the bonding and charge state of alkali metal atoms on an ultrathin magnesium oxide layer on a Ag substrate. We observe a magnetic moment of 1 μB for Li2, LiNa, and Na2 dimers corresponding to spin radicals with a charge state of +1e. Single alkali atoms have the same charge state and no magnetic moment. The ionization of the adsorbates is attributed to charge transfer through the oxide to the metal substrate. Our work highlights the potential of EPR-STM to provide insight into dopant atoms that are relevant for the control of the electrical properties of surfaces and nanodevices.
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Affiliation(s)
- Stepan Kovarik
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
| | - Roberto Robles
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU), Paseo Manuel de Lardizabal 5, San Sebastián 20018, Spain
| | - Richard Schlitz
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
| | - Tom Sebastian Seifert
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
- Department of Physics, Freie Universität Berlin, Berlin 14195, Germany
| | - Nicolas Lorente
- Centro de Física de Materiales CFM/MPC (CSIC-UPV/EHU), Paseo Manuel de Lardizabal 5, San Sebastián 20018, Spain
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, San Sebastián 20018, Spain
| | - Pietro Gambardella
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
| | - Sebastian Stepanow
- Department of Materials, ETH Zurich, Hönggerbergring 64, Zürich CH-8093, Switzerland
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12
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Lee S, Min B, Bang J. Substrate effect on hydrogen evolution reaction in two-dimensional Mo 2C monolayers. Sci Rep 2022; 12:6076. [PMID: 35414153 PMCID: PMC9005693 DOI: 10.1038/s41598-022-09935-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/29/2022] [Indexed: 11/11/2022] Open
Abstract
The physical and chemical properties of atomically thin two-dimensional (2D) materials can be modified by the substrates. In this study, the substrate effect on the electrocatalytic hydrogen evolution reaction (HER) in 2D Mo2C monolayers was investigated using first principles calculations. The isolated Mo2C monolayer shows large variation in HER activity depending on hydrogen coverage: it has relatively low activity at low hydrogen coverage but high activity at high hydrogen coverage. Among Ag, Au, Cu, and graphene substrates, the HER activity is improved on the Ag and Cu substrates especially at low hydrogen coverage, while the effects of the Au and graphene substrates on the HER activity are insignificant. The improvement is caused by the charge redistribution in the Mo2C layer on the substrate, and therefore the HER activity becomes high for any hydrogen coverage on the Ag and Cu substrates. Our results suggest that, in two-dimensional electrocatalysis, the substrate has a degree of freedom to tune the catalytic activity.
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Affiliation(s)
- Sujin Lee
- Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 04620, Korea
| | - Byungjoon Min
- Department of Physics, Chungbuk National University, Cheongju, 28644, Republic of Korea.,Research Institute for Nanoscale Science and Technology, Cheongju, 28644, Republic of Korea
| | - Junhyeok Bang
- Department of Physics, Chungbuk National University, Cheongju, 28644, Republic of Korea. .,Research Institute for Nanoscale Science and Technology, Cheongju, 28644, Republic of Korea.
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13
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Surnev S, Netzer FP. Tungsten and molybdenum oxide nanostructures: two-dimensional layers and nanoclusters. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:233001. [PMID: 35045403 DOI: 10.1088/1361-648x/ac4ceb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
W- and Mo-oxides form an interesting class of materials, featuring structural complexities, stoichiometric flexibility, and versatile physical and chemical properties that render them attractive for many applications in diverse fields of nanotechnologies. In nanostructured form, novel properties and functionalities emerge as a result of quantum size and confinement effects. In this topical review, W- and Mo-oxide nanosystems are examined with particular emphasis on two-dimensional (2D) layers and small molecular-type clusters. We focus on the epitaxial growth of 2D layers on metal single crystal surfaces and investigate their novel geometries and structures by a surface science approach. The coupling between the oxide overlayer and the metal substrate surface is a decisive element in the formation of the oxide structures and interfacial strain and charge transfer are shown to determine the lowest energy structures. Atomic structure models as determined by density functional theory (DFT) simulations are reported and discussed for various interface situations, with strong and weak coupling. Free-standing (quasi-)2D oxide layers, so-called oxide nanosheets, are attracting a growing interest recently in the applied research community because of their easy synthesis via wet-chemical routes. Although they consist typically of several atomic layers thick-not always homogeneous-platelet systems, their quasi-2D character induces a number of features that make them attractive for optoelectronic, sensor or biotechnological device applications. A brief account of recently published preparation procedures of W- and Mo-oxide nanosheets and some prototypical examples of proof of concept applications are reported here. (MO3)3(M = W, Mo) clusters can be generated in the gas phase in nearly monodisperse form by a simple vacuum sublimation technique. These clusters, interesting molecular-type structures by their own account, can be deposited on a solid surface in a controlled way and be condensed into 2D W- and Mo-oxide layers; solid-state chemical reactions with pre-deposited surface oxide layers to form 2D ternary oxide compounds (tungstates, molybdates) have also been reported. The clusters have been proposed as model systems for molecular studies of reactive centres in catalytic reactions. Studies of the catalysis of (MO3)3clusters in unsupported and supported forms, using the conversion of alcohols as model reactions, are discussed. Finally, we close with a brief outlook of future perspectives.
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Affiliation(s)
- Svetlozar Surnev
- Surface and Interface Physics, Institute of Physics, Karl-Franzens University Graz, A-8010 GRAZ, Austria
| | - Falko P Netzer
- Surface and Interface Physics, Institute of Physics, Karl-Franzens University Graz, A-8010 GRAZ, Austria
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14
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Sadakiyo M. Support effects of metal-organic frameworks in heterogeneous catalysis. NANOSCALE 2022; 14:3398-3406. [PMID: 35179154 DOI: 10.1039/d1nr07659k] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Catalytic support effects have been widely studied as a key factor for creating highly active heterogeneous catalysts with limited amounts of rare metal elements. Recently, support effects of metal-organic frameworks (MOFs) started to be investigated using their wide variety in pore size, electronic state, and selective adsorption property. Three types of support effects, namely molecular sieving, charge transfer, and substrate adsorption effects, have been reported on composite catalysts of metal nanoparticles supported on MOFs (M/MOFs). The current reports on heterogeneous catalysis in M/MOFs clearly demonstrated that both catalytic activity and product selectivity can be drastically enhanced and modulated by MOF supports through these support effects, and that application of MOFs as the supports is beneficial for creating novel high performance catalysts with metal nanoparticles. This minireview summarizes the catalytic properties and support effects observed on M/MOFs.
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Affiliation(s)
- Masaaki Sadakiyo
- Department of Applied Chemistry, Faculty of Science Division I, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
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15
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Kuklin MS, Eklund K, Linnera J, Ropponen A, Tolvanen N, Karttunen AJ. Structural Properties and Magnetic Ground States of 100 Binary d-Metal Oxides Studied by Hybrid Density Functional Methods. Molecules 2022; 27:molecules27030874. [PMID: 35164135 PMCID: PMC8838575 DOI: 10.3390/molecules27030874] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/23/2022] [Accepted: 01/24/2022] [Indexed: 02/04/2023] Open
Abstract
d-metal oxides play a crucial role in numerous technological applications and show a great variety of magnetic properties. We have systematically investigated the structural properties, magnetic ground states, and fundamental electronic properties of 100 binary d-metal oxides using hybrid density functional methods and localized basis sets composed of Gaussian-type functions. The calculated properties are compared with experimental information in all cases where experimental data are available. The used PBE0 hybrid density functional method describes the structural properties of the studied d-metal oxides well, except in the case of molecular oxides with weak intermolecular forces between the molecular units. Empirical D3 dispersion correction does not improve the structural description of the molecular oxides. We provide a database of optimized geometries and magnetic ground states to facilitate future studies on the more complex properties of the binary d-metal oxides.
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16
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Padavala SKM, Artyushkova K, Boettcher S, Nemšák S, Stoerzinger KA. Understanding methanol dissociative adsorption and oxidation on amorphous oxide films. Faraday Discuss 2022; 236:58-70. [DOI: 10.1039/d1fd00109d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Interactions between a transition metal (oxide) catalyst and a support can tailor the number and nature of active sites, for instance in the methanol oxidation reaction. We here use ambient...
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17
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Mine S, Toyao T, Hinuma Y, Shimizu KI. Understanding and controlling the formation of surface anion vacancies for catalytic applications. Catal Sci Technol 2022. [DOI: 10.1039/d2cy00014h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Systematic computational efforts aimed at calculating surface anion vacancy formation energies as important descriptors of catalytic performance are summarized.
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Affiliation(s)
- Shinya Mine
- Institute for Catalysis, Hokkaido University, N-21, W-10, 1-5, Sapporo 001-0021, Japan
| | - Takashi Toyao
- Institute for Catalysis, Hokkaido University, N-21, W-10, 1-5, Sapporo 001-0021, Japan
- Elements Strategy Initiative for Catalysts and Batteries, Kyoto University, Katsura, Nishigyo, Kyoto 615-8520, Japan
| | - Yoyo Hinuma
- Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda 563-8577, Japan
| | - Ken-ichi Shimizu
- Institute for Catalysis, Hokkaido University, N-21, W-10, 1-5, Sapporo 001-0021, Japan
- Elements Strategy Initiative for Catalysts and Batteries, Kyoto University, Katsura, Nishigyo, Kyoto 615-8520, Japan
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18
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Pacchioni G. From Li clusters to nanocatalysis: A brief tour of 40 years of cluster chemistry. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2021.120680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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19
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Jašik J, Fortunelli A, Vajda S. Exploring the materials space in the smallest particle size range: From heterogeneous catalysis to electrocatalysis and photocatalysis. Phys Chem Chem Phys 2022; 24:12083-12115. [DOI: 10.1039/d1cp05677h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrasmall clusters of subnanometer size can possess unique and even unexpected physical and chemical propensities which make them interesting in various fields of basic science and for potential applications, such...
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20
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Affiliation(s)
- Zhenhua Zhang
- Department, Institution, Address 1 Hefei National Laboratory for Physical Sciences at the Microscale Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes and Department of Chemical Physics, University of Science and Technology of China Hefei 230026 People's Republic of China
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University Jinhua 321004 People's Republic of China
| | - Rui You
- Department, Institution, Address 1 Hefei National Laboratory for Physical Sciences at the Microscale Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes and Department of Chemical Physics, University of Science and Technology of China Hefei 230026 People's Republic of China
| | - Weixin Huang
- Department, Institution, Address 1 Hefei National Laboratory for Physical Sciences at the Microscale Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes and Department of Chemical Physics, University of Science and Technology of China Hefei 230026 People's Republic of China
- Dalian National Laboratory for Clean Energy Dalian 116023 People's Republic of China
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21
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Wang M, Feng Z. Interfacial processes in electrochemical energy systems. Chem Commun (Camb) 2021; 57:10453-10468. [PMID: 34494049 DOI: 10.1039/d1cc01703a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Electrochemical energy systems such as batteries, water electrolyzers, and fuel cells are considered as promising and sustainable energy storage and conversion devices due to their high energy densities and zero or negative carbon dioxide emission. However, their widespread applications are hindered by many technical challenges, such as the low efficiency and poor long-term cyclability, which are mostly affected by the changes at the reactant/electrode/electrolyte interfaces. These interfacial processes involve ion/electron transfer, molecular/ion adsorption/desorption, and complex interface restructuring, which lead to irreversible modifications to the electrodes and the electrolyte. The understanding of these interfacial processes is thus crucial to provide strategies for solving those problems. In this review, we will discuss different interfacial processes at three representative interfaces, namely, solid-gas, solid-liquid, and solid-solid, in various electrochemical energy systems, and how they could influence the performance of electrochemical systems.
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Affiliation(s)
- Maoyu Wang
- School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon, USA.
| | - Zhenxing Feng
- School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon, USA.
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22
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Salcedo A, Lustemberg PG, Rui N, Palomino RM, Liu Z, Nemsak S, Senanayake SD, Rodriguez JA, Ganduglia-Pirovano MV, Irigoyen B. Reaction Pathway for Coke-Free Methane Steam Reforming on a Ni/CeO 2 Catalyst: Active Sites and the Role of Metal-Support Interactions. ACS Catal 2021; 11:8327-8337. [PMID: 34306812 PMCID: PMC8294006 DOI: 10.1021/acscatal.1c01604] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/28/2021] [Indexed: 11/28/2022]
Abstract
![]()
Methane steam reforming
(MSR) plays a key role in the production
of syngas and hydrogen from natural gas. The increasing interest in
the use of hydrogen for fuel cell applications demands development
of catalysts with high activity at reduced operating temperatures.
Ni-based catalysts are promising systems because of their high activity
and low cost, but coke formation generally poses a severe problem.
Studies of ambient-pressure X-ray photoelectron spectroscopy (AP-XPS)
indicate that CH4/H2O gas mixtures react with
Ni/CeO2(111) surfaces to form OH, CHx, and CHxO at 300 K. All of these
species are easy to form and desorb at temperatures below 700 K when
the rate of the MSR process is accelerated. Density functional theory
(DFT) modeling of the reaction over ceria-supported small Ni nanoparticles
predicts relatively low activation barriers between 0.3 and 0.7 eV
for complete dehydrogenation of methane to carbon and the barrierless
activation of water at interfacial Ni sites. Hydroxyls resulting from
water activation allow for CO formation via a COH intermediate with
a barrier of about 0.9 eV, which is much lower than that through a
pathway involving lattice oxygen from ceria. Neither methane nor water
activation is a rate-determining step, and the OH-assisted CO formation
through the COH intermediate constitutes a low-barrier pathway that
prevents carbon accumulation. The interactions between Ni and the
ceria support and the low metal loading are crucial for the reaction
to proceed in a coke-free and efficient way. These results pave the
way for further advances in the design of stable and highly active
Ni-based catalysts for hydrogen production.
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Affiliation(s)
- Agustín Salcedo
- Departamento de Ingeniería Química, Facultad de Ingeniería, Universidad de Buenos Aires (UBA), Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
- Instituto de Tecnologías del Hidrógeno y Energías Sostenibles (ITHES, CONICET-UBA), Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
| | - Pablo G. Lustemberg
- Instituto de Catálisis y Petroleoquímica (ICP, CSIC), 28049 Madrid, Spain
- Instituto de Física Rosario (IFIR, CONICET-UNR), S2000EKF Rosario, Santa Fe, Argentina
| | - Ning Rui
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Robert M. Palomino
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Zongyuan Liu
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Slavomir Nemsak
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Sanjaya D. Senanayake
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - José A. Rodriguez
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | | | - Beatriz Irigoyen
- Departamento de Ingeniería Química, Facultad de Ingeniería, Universidad de Buenos Aires (UBA), Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
- Instituto de Tecnologías del Hidrógeno y Energías Sostenibles (ITHES, CONICET-UBA), Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
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23
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Rupprechter G. Operando Surface Spectroscopy and Microscopy during Catalytic Reactions: From Clusters via Nanoparticles to Meso-Scale Aggregates. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2004289. [PMID: 33694320 DOI: 10.1002/smll.202004289] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 02/16/2021] [Indexed: 05/16/2023]
Abstract
Operando characterization of working catalysts, requiring per definitionem the simultaneous measurement of catalytic performance, is crucial to identify the relevant catalyst structure, composition and adsorbed species. Frequently applied operando techniques are discussed, including X-ray absorption spectroscopy, near ambient pressure X-ray photoelectron spectroscopy and infrared spectroscopy. In contrast to these area-averaging spectroscopies, operando surface microscopy by photoemission electron microscopy delivers spatially-resolved data, directly visualizing catalyst heterogeneity. For thorough interpretation, the experimental results should be complemented by density functional theory. The operando approach enables to identify changes of cluster/nanoparticle structure and composition during ongoing catalytic reactions and reveal how molecules interact with surfaces and interfaces. The case studies cover the length-scales from clusters via nanoparticles to meso-scale aggregates, and demonstrate the benefits of specific operando methods. Restructuring, ligand/atom mobility, and surface composition alterations during the reaction may have pronounced effects on activity and selectivity. The nanoscale metal/oxide interface steers catalytic performance via a long ranging effect. Combining operando spectroscopy with switching gas feeds or concentration-modulation provides further mechanistic insights. The obtained fundamental understanding is a prerequisite for improving catalytic performance and for rational design.
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Affiliation(s)
- Günther Rupprechter
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, Vienna, 1060, Austria
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24
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Ma J, Kim JH, Na J, Min J, Lee GH, Jo S, Kim CS. Enhanced Polymerization and Surface Hardness of Colloidal Siloxane Films via Electron Beam Irradiation. ACS OMEGA 2021; 6:13384-13390. [PMID: 34056485 PMCID: PMC8158831 DOI: 10.1021/acsomega.1c01429] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
Electron beam (EB) curing is a foldable hard coating process and has attracted significant research attention in the field of flexible electronic devices. In this study, we report a method for enhancing material surface hardness with low-energy EB curing in a short time. The low-energy EB improved the coating hardness of films by inducing cross-linking polymerization of the silicon-containing monomer. The hardness of the cured coating layer was measured as 3 H using a pencil hardness tester, and the transparency of the coating was higher than 90%. Owing to a series of cross-linking reactions between Si-O-C and Si-OH groups under EB curing and the formation of Si-Si bonds, the cured layer exhibited remarkable durability in the 100000-flexible cycle test. Additionally, the natural oxidation of the C-O groups on the surface of the coating formed carboxyl groups that improved the hydrophilic properties of the coating layer. To the best of our knowledge, this is the first study to propose that the hardness of polyethylene terephthalate films can be improved using low-energy EBs to rapidly cure silicon-containing coatings. Our results provide a novel and commercially viable approach for improving the hardness of touch screens and foldable displays.
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Affiliation(s)
- Junfei Ma
- Department
of Nano-Bio Convergence, Korea Institute
of Materials Science (KIMS), Changwon 51508, South Korea
- School
of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, Daegu 41566, South Korea
| | - Ji-Hyeon Kim
- Department
of Nano-Bio Convergence, Korea Institute
of Materials Science (KIMS), Changwon 51508, South Korea
| | - Jaehun Na
- Gimhae
Industry Promotion & Bio-medical Foundation, 701 Biomedical Techno Town, Goldenroot St. 80-59, Gimhae 50969, Gyeongnam, South Korea
| | - Junki Min
- Gimhae
Industry Promotion & Bio-medical Foundation, 701 Biomedical Techno Town, Goldenroot St. 80-59, Gimhae 50969, Gyeongnam, South Korea
| | - Ga-Hyun Lee
- Department
of Nano-Bio Convergence, Korea Institute
of Materials Science (KIMS), Changwon 51508, South Korea
- School
of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, Daegu 41566, South Korea
| | - Sungjin Jo
- School
of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, Daegu 41566, South Korea
| | - Chang Su Kim
- Department
of Nano-Bio Convergence, Korea Institute
of Materials Science (KIMS), Changwon 51508, South Korea
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25
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Das T, Tosoni S, Pacchioni G. Role of support in tuning the properties of single atom catalysts: Cu, Ag, Au, Ni, Pd, and Pt adsorption on SiO 2/Ru, SiO 2/Pt, and SiO 2/Si ultrathin films. J Chem Phys 2021; 154:134706. [PMID: 33832274 DOI: 10.1063/5.0048104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The role of the support in tuning the properties of transition metal (TM) atoms is studied by means of density functional theory calculations. We have considered the adsorption of Cu, Ag, Au, Ni, Pd, and Pt atoms on crystalline silica bilayers, either free-standing or supported on Ru(0001) and Pt(111) metal surfaces. These systems have been compared with an hydroxylated SiO2/Si(100) film simulating the native oxide formed on a silicon wafer. The properties of the TM atoms change significantly on the various supports. While the unsupported silica bilayer weakly binds some of the TM atoms studied, the SiO2/Ru(0001) or SiO2/Pt(111) supports exhibit enhanced reactivity, sometimes resulting in a net electron transfer with the formation of charged species. Differences in the behavior of SiO2/Ru(0001) and SiO2/Pt(111) are rationalized in terms of different work functions and metal/oxide interfacial distances. No electron transfer is observed on the SiO2/Si(100) films. Here, the presence of hydroxyl groups on the surface provides relatively strong binding sites for the TM atoms that can be stabilized by the interaction with one or two OH groups. The final aspect that has been investigated is the porosity of the silica bilayer, at variance with the dense SiO2/Si(100) film. Depending on the atomic size, some TM atoms can penetrate spontaneously through the six-membered silica rings and become stabilized in the pores of the bilayer or at the SiO2/metal interface. This study shows how very different chemical properties can be obtained by depositing the same TM atom on different silica supports.
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Affiliation(s)
- Tilak Das
- Dipartimento di Scienza dei Materiali, Università degli Studi Milano-Bicocca, via R. Cozzi, 55-20125 Milano, Italy
| | - Sergio Tosoni
- Dipartimento di Scienza dei Materiali, Università degli Studi Milano-Bicocca, via R. Cozzi, 55-20125 Milano, Italy
| | - Gianfranco Pacchioni
- Dipartimento di Scienza dei Materiali, Università degli Studi Milano-Bicocca, via R. Cozzi, 55-20125 Milano, Italy
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26
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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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27
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Miyazaki R, Jin X, Yoshii D, Yatabe T, Yabe T, Mizuno N, Yamaguchi K, Hasegawa JY. Mechanistic study of C–H bond activation by O2 on negatively charged Au clusters: α,β-dehydrogenation of 1-methyl-4-piperidone by supported Au catalysts. Catal Sci Technol 2021. [DOI: 10.1039/d1cy00178g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aerobic C–H activation by Au/OMS-2 catalyst is driven by charge transfer from OMS-2 to adsorbed O2via Au cluster.
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Affiliation(s)
- Ray Miyazaki
- Institute for Catalysis
- Hokkaido University
- Sapporo
- Japan
| | - Xiongjie Jin
- Department of Chemistry and Biotechnology
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
| | - Daichi Yoshii
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
| | - Takafumi Yatabe
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
| | - Tomohiro Yabe
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
| | - Noritaka Mizuno
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
| | - Kazuya Yamaguchi
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
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28
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Hinuma Y, Mine S, Toyao T, Maeno Z, Shimizu KI. Surface activation by electron scavenger metal nanorod adsorption on TiH 2, TiC, TiN, and Ti 2O 3. Phys Chem Chem Phys 2021; 23:16577-16593. [PMID: 34320045 DOI: 10.1039/d1cp02068d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metal/oxide support perimeter sites are known to provide unique properties because the nearby metal changes the local environment on the support surface. In particular, the electron scavenger effect reduces the energy necessary for surface anion desorption, and thereby contributes to activation of the (reverse) Mars-van Krevelen mechanism. This study investigated the possibility of such activation in hydrides, carbides, nitrides, and sulfides. The work functions (WFs) of known hydrides, carbides, nitrides, oxides, and sulfides with group 3, 4, or 5 cations (Sc, Y, La, Ti, Zr, Hf, V, Nb, and Ta) were calculated. The WFs of most hydrides, carbides, and nitrides are smaller than the WF of Ag, implying that the electron scavenger effect may occur when late transition metal nanoparticles are adsorbed on the surface. The WF of oxides and sulfides decreases when reduced. The surface anion vacancy formation energy correlates well with the bulk formation energy in carbides and nitrides, while almost no correlation is found in hydrides because of the small range of surface hydrogen vacancy formation energy values. The electron scavenger effect is explicitly observed in nanorods adsorbed on TiH2 and Ti2O3; the surface vacancy formation energy decreases at anion sites near the nanorod, and charge transfer to the nanorod happens when an anion is removed at such sites. Activation of hydrides, carbides, and nitrides by nanorod adsorption and screening support materials through WF calculation are expected to open up a new category of supported catalysts.
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Affiliation(s)
- Yoyo Hinuma
- Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8502, Japan
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29
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Lei X, Zhang H, Jia Y, Luo Z. Gas-phase preparation and the stability of superatomic Nb 11O 15. Phys Chem Chem Phys 2021; 23:15766-15773. [PMID: 34286767 DOI: 10.1039/d1cp02128a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report a study of the reactions of pure metal clusters Nbn- with dioxygen in the gas phase. It is found that the presence of low-concentration dioxygen reactants results in oxygen-addition products, whereas sufficient high-concentration dioxygen enables oxygen-etching reactions giving rise to molecular niobium oxides. Interestingly, in the presence of a suitable gas flow rate of an intermediate dioxygen concentration, a highly selective product Nb11O15- shows up in the mass spectra. Utilizing density functional theory (DFT) calculations, we have discussed the reactivities of Nbn- (3 ≤ n ≤ 14) clusters with oxygen, and unveiled the reasonable stability of Nb11O15- pertaining to its unique geometric structure with a D5h Nb@Nb10 core fully protected by 15 bridge-oxygen atoms. The oxygen-passivated Nb@Nb10O15- cluster exhibits a large HOMO-LUMO gap (1.46 eV) and effective multicenter bonds with remarkable superatom orbitals for all the 26 valence electrons of the Nb@Nb10 core corresponding to well-staggered energy levels. We illustrate the superatomic features in the Nb@Nb10 metallic core for which the adaptive natural density partitioning (AdNDP) analysis unveils thirteen 11c-2e bonds. Among them, one of the 11c-2e bonds accounts for the superatomic S orbital, three bonds correspond to superatomic P orbitals, another five display vivid D orbital characteristics, and the remaining four 11c-2e bonds are assigned to F orbital features. In addition, the net atomic charge of the center Nb atom is as high as -0.804 |e| rendering core-shell electrostatic interactions and the shielding effect of the Nb10O15 shell.
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Affiliation(s)
- Xin Lei
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Hanyu Zhang
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Yuhan Jia
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China. and University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhixun Luo
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China. and University of Chinese Academy of Sciences, Beijing 100049, China
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30
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Li X, Rupprechter G. Sum frequency generation spectroscopy in heterogeneous model catalysis: a minireview of CO-related processes. Catal Sci Technol 2021. [DOI: 10.1039/d0cy01736a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sum frequency generation (SFG) vibrational spectroscopy is applied to ambient pressure surface science studies of adsorption and catalytic reactions at solid/gas interfaces.
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Affiliation(s)
- Xia Li
- Institute of Materials Chemistry
- Technische Universität Wien
- 1060 Vienna
- Austria
| | - Günther Rupprechter
- Institute of Materials Chemistry
- Technische Universität Wien
- 1060 Vienna
- Austria
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31
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Pramhaas V, Roiaz M, Bosio N, Corva M, Rameshan C, Vesselli E, Grönbeck H, Rupprechter G. Interplay between CO Disproportionation and Oxidation: On the Origin of the CO Reaction Onset on Atomic Layer Deposition-Grown Pt/ZrO 2 Model Catalysts. ACS Catal 2021; 11:208-214. [PMID: 33425478 PMCID: PMC7783867 DOI: 10.1021/acscatal.0c03974] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/04/2020] [Indexed: 11/29/2022]
Abstract
![]()
Pt/ZrO2 model catalysts were prepared by atomic layer
deposition (ALD) and examined at mbar pressure by operando sum frequency generation (SFG) spectroscopy and near-ambient pressure
X-ray photoelectron spectroscopy (NAP-XPS) combined with differentially
pumped mass spectrometry (MS). ALD enables creating model systems
ranging from Pt nanoparticles to bulk-like thin films. Polarization-dependent
SFG of CO adsorption reveals both the adsorption configuration and
the Pt particle morphology. By combining experimental data with ab initio density functional theory (DFT) calculations,
we show that the CO reaction onset is determined by a delicate balance
between CO disproportionation (Boudouard reaction) and oxidation.
CO disproportionation occurs on low-coordinated Pt sites, but only
at high CO coverages and when the remaining C atom is stabilized by
a favorable coordination. Thus, under the current conditions, initial
CO oxidation is found to be strongly influenced by the removal of
carbon deposits formed through disproportionation mechanisms rather
than being determined by the CO and oxygen inherent activity. Accordingly,
at variance with the general expectation, rough Pt nanoparticles are
seemingly less active than smoother Pt films. The applied approach
enables bridging both the “materials and pressure gaps”.
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Affiliation(s)
- Verena Pramhaas
- Institute of Materials Chemistry, Technische Universität Wien, Vienna 1060, Austria
| | - Matteo Roiaz
- Institute of Materials Chemistry, Technische Universität Wien, Vienna 1060, Austria
| | - Noemi Bosio
- Department of Physics and Competence Centre for Catalysis, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Manuel Corva
- Department of Physics, University of Trieste, Via Valerio 2, 34127 Trieste, Italy
- IOM-CNR Laboratorio TASC, Area Science Park, SS 14 km 163.5, Basovizza, 34149 Trieste, Italy
| | - Christoph Rameshan
- Institute of Materials Chemistry, Technische Universität Wien, Vienna 1060, Austria
| | - Erik Vesselli
- Department of Physics, University of Trieste, Via Valerio 2, 34127 Trieste, Italy
- IOM-CNR Laboratorio TASC, Area Science Park, SS 14 km 163.5, Basovizza, 34149 Trieste, Italy
| | - Henrik Grönbeck
- Department of Physics and Competence Centre for Catalysis, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Günther Rupprechter
- Institute of Materials Chemistry, Technische Universität Wien, Vienna 1060, Austria
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32
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Abstract
The unprecedented ability of computations to probe atomic-level details of catalytic systems holds immense promise for the fundamentals-based bottom-up design of novel heterogeneous catalysts, which are at the heart of the chemical and energy sectors of industry. Here, we critically analyze recent advances in computational heterogeneous catalysis. First, we will survey the progress in electronic structure methods and atomistic catalyst models employed, which have enabled the catalysis community to build increasingly intricate, realistic, and accurate models of the active sites of supported transition-metal catalysts. We then review developments in microkinetic modeling, specifically mean-field microkinetic models and kinetic Monte Carlo simulations, which bridge the gap between nanoscale computational insights and macroscale experimental kinetics data with increasing fidelity. We finally review the advancements in theoretical methods for accelerating catalyst design and discovery. Throughout the review, we provide ample examples of applications, discuss remaining challenges, and provide our outlook for the near future.
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Affiliation(s)
- Benjamin W J Chen
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Lang Xu
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Manos Mavrikakis
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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33
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Haunold T, Rameshan C, Bukhtiyarov AV, Rupprechter G. An ultrahigh vacuum-compatible reaction cell for model catalysis under atmospheric pressure flow conditions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:125101. [PMID: 33379966 DOI: 10.1063/5.0026171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 11/06/2020] [Indexed: 06/12/2023]
Abstract
Atmospheric pressure reactions on model catalysts are typically performed in so-called high-pressure cells, with product analysis performed by gas chromatography (GC) or mass spectrometry (MS). However, in most cases, these cells have a large volume (liters) so that the reactions on catalysts with only cm2 surface area can be carried out only in the (recirculated) batch mode to accumulate sufficient product amounts. Herein, we describe a novel small-volume (milliliters) catalytic reactor that enables kinetic studies under atmospheric pressure flow conditions. The cell is located inside an ultrahigh vacuum chamber that is deliberately limited to basic functions. Model catalyst samples are mounted inside the reactor cell, which is locked to an oven for external heating and closed by using an extendable/retractable gas dosing tube. Reactant and product analyses are performed by both micro-GC and MS. The functionality of the new design is demonstrated by catalytic ethylene (C2H4) hydrogenation on polycrystalline Pt and Pd foils.
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Affiliation(s)
- Thomas Haunold
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
| | - Christoph Rameshan
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
| | - Andrey V Bukhtiyarov
- Boreskov Institute of Catalysis SB RAS, Lavrentieva Ave. 5, 630090 Novosibirsk, Russia
| | - Günther Rupprechter
- Institute of Materials Chemistry, Technische Universität Wien, Getreidemarkt 9/BC/01, 1060 Vienna, Austria
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34
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Schultz JF, Mahapatra S, Li L, Jiang N. The Expanding Frontiers of Tip-Enhanced Raman Spectroscopy. APPLIED SPECTROSCOPY 2020; 74:1313-1340. [PMID: 32419485 DOI: 10.1177/0003702820932229] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Fundamental understanding of chemistry and physical properties at the nanoscale enables the rational design of interface-based systems. Surface interactions underlie numerous technologies ranging from catalysis to organic thin films to biological systems. Since surface environments are especially prone to heterogeneity, it becomes crucial to characterize these systems with spatial resolution sufficient to localize individual active sites or defects. Spectroscopy presents as a powerful means to understand these interactions, but typical light-based techniques lack sufficient spatial resolution. This review describes the growing number of applications for the nanoscale spectroscopic technique, tip-enhanced Raman spectroscopy (TERS), with a focus on developments in areas that involve measurements in new environmental conditions, such as liquid, electrochemical, and ultrahigh vacuum. The expansion into unique environments enables the ability to spectroscopically define chemistry at the spatial limit. Through the confinement and enhancement of light at the apex of a plasmonic scanning probe microscopy tip, TERS is able to yield vibrational fingerprint information of molecules and materials with nanoscale resolution, providing insight into highly localized chemical effects.
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Affiliation(s)
- Jeremy F Schultz
- Department of Chemistry, 14681University of Illinois at Chicago, Chicago, USA
| | - Sayantan Mahapatra
- Department of Chemistry, 14681University of Illinois at Chicago, Chicago, USA
| | - Linfei Li
- Department of Chemistry, 14681University of Illinois at Chicago, Chicago, USA
| | - Nan Jiang
- Department of Chemistry, 14681University of Illinois at Chicago, Chicago, USA
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35
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Bagus PS, Brundle C, Ilton ES. A rigorous non-empirical theoretical analysis of the 2p XPS of NiO: Is it necessary to invoke nonlocal screening? J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114135] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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36
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Schultz JF, Li S, Jiang S, Jiang N. Optical scanning tunneling microscopy based chemical imaging and spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:463001. [PMID: 32702674 DOI: 10.1088/1361-648x/aba8c7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/23/2020] [Indexed: 06/11/2023]
Abstract
Through coupling optical processes with the scanning tunneling microscope (STM), single-molecule chemistry and physics have been investigated at the ultimate spatial and temporal limit. Electrons and photons can be used to drive interactions and reactions in chemical systems and simultaneously probe their characteristics and consequences. In this review we introduce and review methods to couple optical imaging and spectroscopy with scanning tunneling microscopy. The integration of the STM and optical spectroscopy provides new insights into individual molecular adsorbates, surface-supported molecular assemblies, and two-dimensional materials with subnanoscale resolution, enabling the fundamental study of chemistry at the spatial and temporal limit. The inelastic scattering of photons by molecules and materials, that results in unique and sensitive vibrational fingerprints, will be considered with tip-enhanced Raman spectroscopy. STM-induced luminescence examines the intrinsic luminescence of organic adsorbates and their energy transfer and charge transfer processes with their surroundings. We also provide a survey of recent efforts to probe the dynamics of optical excitation at the molecular level with scanning tunneling microscopy in the context of light-induced photophysical and photochemical transformations.
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Affiliation(s)
- Jeremy F Schultz
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60607, United States of America
| | - Shaowei Li
- Department of Chemistry and Biochemistry, University of California, San Diego, CA 92093, United States of America
- Kavli Energy NanoScience Institute, University of California, Berkeley, CA 94720, United States of America
| | - Song Jiang
- Université de Strasbourg, CNRS, IPCMS, UMR 7504, F-67000 Strasbourg, France
| | - Nan Jiang
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60607, United States of America
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37
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Howard-Fabretto L, Andersson GG. Metal Clusters on Semiconductor Surfaces and Application in Catalysis with a Focus on Au and Ru. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1904122. [PMID: 31854037 DOI: 10.1002/adma.201904122] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 09/13/2019] [Indexed: 06/10/2023]
Abstract
Metal clusters typically consist of two to a few hundred atoms and have unique properties that change with the type and number of atoms that form the cluster. Metal clusters can be generated with a precise number of atoms, and therefore have specific size, shape, and electronic structures. When metal clusters are deposited onto a substrate, their shape and electronic structure depend on the interaction with the substrate surface and thus depend on the properties of both the clusters and those of the substrate. Deposited metal clusters have discrete, individual electron energy levels that differ from the electron energy levels in the constituting individual atoms, isolated clusters, and the respective bulk material. The properties of clusters with a focus on Au and Ru, the methods to generate metal clusters, and the methods of deposition of clusters onto substrate surfaces are covered. The properties of cluster-modified surfaces are important for their application. The main application covered here is catalysis, and the methods for characterization of the cluster-modified surfaces are described.
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Affiliation(s)
- Liam Howard-Fabretto
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, SA, 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA, 5042, Australia
| | - Gunther G Andersson
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, SA, 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA, 5042, Australia
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38
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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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39
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Ruiz-Gómez S, Mandziak A, Prieto JE, Aristu M, Trapero EM, Soria GD, Quesada A, Foerster M, Aballe L, de la Figuera J. A real-time XAS PEEM study of the growth of cobalt iron oxide on Ru(0001). J Chem Phys 2020; 152:074704. [PMID: 32087633 DOI: 10.1063/1.5140886] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The growth of mixed cobalt-iron oxides on Ru(0001) by high-temperature oxygen-assisted molecular beam epitaxy has been monitored in real time and real space by x-ray absorption photoemission microscopy. The initial composition is a mixed Fe-Co(II) oxide wetting layer, reflecting the ratio of the deposited materials. However, as subsequent growth of three dimensional spinel islands nucleating on this wetting layer takes place, the composition of the oxide in the wetting layer changes as iron is transferred into the spinel islands. The composition of the islands themselves also changes during growth.
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Affiliation(s)
- S Ruiz-Gómez
- Dpto. de Física de Materiales, Univ. Complutense de Madrid, Madrid E-28040, Spain
| | - A Mandziak
- Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain
| | - J E Prieto
- Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain
| | - M Aristu
- Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain
| | - E M Trapero
- Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain
| | - G D Soria
- Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain
| | - A Quesada
- Instituto de Cerámica y Vidrio, CSIC, Madrid E-28049, Spain
| | - M Foerster
- ALBA Synchrotron Light Facility, CELLS, Cerdanyola del Vallés E-08290, Spain
| | - L Aballe
- ALBA Synchrotron Light Facility, CELLS, Cerdanyola del Vallés E-08290, Spain
| | - J de la Figuera
- Instituto de Química Física "Rocasolano," CSIC, Madrid E-28006, Spain
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40
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Buendía F, Anzaldo AT, Vital C, Beltrán MR. O 2 activation by AuAg clusters on a defective (100)MgO surface. J Chem Phys 2020; 152:024303. [PMID: 31941299 DOI: 10.1063/1.5129462] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In the present work, we discuss the electronic properties of supported dispersed bimetallic clusters with respect to their size, geometry, and Aun/Agm (n + m = 6) composition. We have studied with supercell-density functional theory calculations the role of the charge transfer from the MgO defective support toward the cluster in the activation of O2 by AunAgm clusters. We first considered gas-phase clusters with different atomic compositions; then, we deposited all of them on a pristine (100)MgO surface and finally on a more realistic (100)MgO F-center. We performed a global and unrestricted search of the (cluster + surface) geometry. The Mexican enhanced genetic algorithm has been used to exhaustively explore the potential energy surface. Our results show that O2 activation depends on the Aun/Agm ratio. It has been found that both metals involved play different and important roles toward (a) the actual O2 dissociation and (b) weakening of the oxygen-cluster bond, which, in turn, may promote the possibility of a catalytic process to take place, such as the oxidation process of CO and NOx among others.
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Affiliation(s)
- F Buendía
- Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, 01000 CDMX, Mexico
| | - A T Anzaldo
- Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apdo. 70-360, C. P. 04510, Coyoacán, Ciudad de México, Mexico
| | - Carlos Vital
- Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apdo. 70-360, C. P. 04510, Coyoacán, Ciudad de México, Mexico
| | - M R Beltrán
- Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apdo. 70-360, C. P. 04510, Coyoacán, Ciudad de México, Mexico
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41
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Sakaushi K, Kumeda T, Hammes-Schiffer S, Melander MM, Sugino O. Advances and challenges for experiment and theory for multi-electron multi-proton transfer at electrified solid–liquid interfaces. Phys Chem Chem Phys 2020; 22:19401-19442. [DOI: 10.1039/d0cp02741c] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Understanding microscopic mechanism of multi-electron multi-proton transfer reactions at complexed systems is important for advancing electrochemistry-oriented science in the 21st century.
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Affiliation(s)
- Ken Sakaushi
- Center for Green Research on Energy and Environmental Materials
- National Institute for Materials Science
- Ibaraki 305-0044
- Japan
| | - Tomoaki Kumeda
- Center for Green Research on Energy and Environmental Materials
- National Institute for Materials Science
- Ibaraki 305-0044
- Japan
| | | | - Marko M. Melander
- Nanoscience Center
- Department of Chemistry
- University of Jyväskylä
- Jyväskylä
- Finland
| | - Osamu Sugino
- The Institute of Solid State Physics
- the University of Tokyo
- Chiba 277-8581
- Japan
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42
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Rötzer MD, Krause M, Crampton AS, Heiz U, Yoon B, Landman U. Nanotuning via Local Work Function Control: Ethylene Hydrogenation on Supported Pt Nanoclusters. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03890] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marian D. Rötzer
- Lehrstuhl für Physikalische Chemie, Catalysis Research Center & Chemistry Department, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Maximilian Krause
- Lehrstuhl für Physikalische Chemie, Catalysis Research Center & Chemistry Department, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Andrew S. Crampton
- Lehrstuhl für Physikalische Chemie, Catalysis Research Center & Chemistry Department, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Ueli Heiz
- Lehrstuhl für Physikalische Chemie, Catalysis Research Center & Chemistry Department, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Bokwon Yoon
- 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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Wöll C. Structure and Chemical Properties of Oxide Nanoparticles Determined by Surface-Ligand IR Spectroscopy. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04016] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christof Wöll
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
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44
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Wu P, Wu Z, Mullins DR, Yang SZ, Han X, Zhang Y, Foo GS, Li H, Zhu W, Dai S, Zhu H. Promoting Pt catalysis for CO oxidation via the Mott-Schottky effect. NANOSCALE 2019; 11:18568-18574. [PMID: 31287484 DOI: 10.1039/c9nr04055b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
CO oxidation is an important reaction both experimentally and industrially, and its performance is usually dominated by the charge states of catalysts. For example, CO oxidation on the platinum (Pt) surface requires a properly charged state for the balance of adsorption and activation of CO and O2. Here, we present "Mott-Schottky modulated catalysis" on Pt nanoparticles (NPs) via an electron-donating carbon nitride (CN) support with a tunable Fermi level. We demonstrate that properly-charged Pt presents an excellent catalytic CO oxidation activity with an initial conversion temperature as low as 25 °C and total CO conversion below 85 °C. The tunable electronic structure of Pt NPs, which is regulated by the Fermi level of CN, is a key factor in dominating the catalytic performance. This "Mott-Schottky modulated catalysis" concept may be extended to maneuver the charge state on other metal catalysts for targeted catalytic reactions.
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Affiliation(s)
- Peiwen Wu
- School of Chemistry and Chemical Engineering; Institute for Energy Research, Jiangsu University, Zhenjiang, 212013, China. and Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
| | - Zili Wu
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
| | - David R Mullins
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
| | - Shi-Ze Yang
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - Xue Han
- Chemical Engineering, Virginia Tech, Blacksburg, VA 24061, USA.
| | - Yafen Zhang
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
| | - Guo Shiou Foo
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
| | - Huaming Li
- School of Chemistry and Chemical Engineering; Institute for Energy Research, Jiangsu University, Zhenjiang, 212013, China.
| | - Wenshuai Zhu
- School of Chemistry and Chemical Engineering; Institute for Energy Research, Jiangsu University, Zhenjiang, 212013, China.
| | - Sheng Dai
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
| | - Huiyuan Zhu
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA. and Chemical Engineering, Virginia Tech, Blacksburg, VA 24061, USA.
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45
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Rossi K, Asara GG, Baletto F. Correlating Oxygen Reduction Reaction Activity and Structural Rearrangements in MgO-Supported Platinum Nanoparticles. Chemphyschem 2019; 20:3037-3044. [PMID: 31386241 PMCID: PMC6916278 DOI: 10.1002/cphc.201900564] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/26/2019] [Indexed: 12/25/2022]
Abstract
We develop a multi‐scale approach towards the design of metallic nanoparticles with applications as catalysts in electrochemical reactions. The here discussed method exploits the relationship between nanoparticle architecture and electrochemical activity and is applied to study the catalytic properties of MgO(100)‐supported Pt nanosystems undergoing solid‐solid and solid‐liquid transitions. We observe that a major increment in the activity is associated to the reconstruction of the interface layers, supporting the need for a full geometrical characterisation of such structures also when in‐operando.
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Affiliation(s)
- Kevin Rossi
- Physics Department, King's College London, London, WC2R 2LS, UK.,Laboratory of Computational Science and Modeling, Institute des Materiaux, Ecole Polytechnique Federale de Lausanne, CH-1015, Lausanne, Switzerland
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46
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Khaniya A, Kaden WE. Epitaxial Growth of Ultrathin δ-Like ΜοΝ Films on Ru(0001). Top Catal 2019. [DOI: 10.1007/s11244-019-01198-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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47
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Cai Z, Shi J, Li W, Wu Y, Zhang Y, Zhang S, Jiang Z. Mussel-Inspired pH-Switched Assembly of Capsules with an Ultrathin and Robust Nanoshell. ACS APPLIED MATERIALS & INTERFACES 2019; 11:28228-28235. [PMID: 31310494 DOI: 10.1021/acsami.9b11445] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Enclosed films, also called capsules, bearing an ultrathin and robust nanoshell have sparked much interest for use in many applications, for which facile preparation methods are urgently pursued. Inspired by the pH-programmed adhesion/cohesion of mussel-secreted foot proteins, polyphenol/polyamine capsules with an ultrathin and robust nanoshell are fabricated through a pH-switched assembly on sacrificial calcium carbonate (CaCO3) templates. Polyphenols adhere to the templates at pH 6.0 and rapidly cohere with polyamines at pH 8.0. The pH-switched assembly process is accomplished in only a few minutes where multiple instances of electrostatic interactions and chemical conjugation between polyphenols and polyamines occur. As a result, the capsules exhibit a nanoshell thickness of ∼10 nm and a superior mechanical strength of ∼1.575 GPa (elasticity modulus). Cell mimics are prepared through encasing enzymes in the lumen and present an activity recovery of ∼70% along with little activity decline during reuse. Amine or phenolic groups on the nanoshell of capsules are then applied to induce the generation of titania or silver nanoparticles, which may expand the applications of the capsules to the photo- and biorelated realms. Our study not only deepens the understanding of the adhering process of mussels but also offers a generic method toward functional materials for diverse applications.
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Affiliation(s)
- Ziyi Cai
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , 92 Weijin Road , Nankai District, Tianjin 300072 , P. R. China
| | - Jiafu Shi
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , 92 Weijin Road , Nankai District, Tianjin 300072 , P. R. China
| | | | - Yizhou Wu
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , 92 Weijin Road , Nankai District, Tianjin 300072 , P. R. China
| | - Yishan Zhang
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , 92 Weijin Road , Nankai District, Tianjin 300072 , P. R. China
| | - Shaohua Zhang
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , 92 Weijin Road , Nankai District, Tianjin 300072 , P. R. China
| | - Zhongyi Jiang
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , 130 Meilong Road , Shanghai 200237 , P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , 92 Weijin Road , Nankai District, Tianjin 300072 , P. R. China
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48
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Recent In Situ/Operando Spectroscopy Studies of Heterogeneous Catalysis with Reducible Metal Oxides as Supports. Catalysts 2019. [DOI: 10.3390/catal9050477] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
For heterogeneous catalysis, the metal catalysts supported on reducible metal oxides, especially CeO2 and TiO2, have long been a research focus because of their excellent catalytic performance in a variety of catalytic reactions. Detailed understanding of the promotion effect of reducible metal oxides on catalytic reactions is beneficial to the rational design of new catalysts. The important catalytic roles of reducible metal oxides are attributed to their intimate interactions with the supported metals (e.g., strong metal-support interaction, electronic metal-support interaction) and unique support structures (e.g., oxygen vacancy, reversible valence change, surface hydroxyl). However, the structures of the catalysts and reaction mechanisms are strongly affected by environmental conditions. For this reason, in situ/operando spectroscopy studies under working conditions are necessary to obtain accurate information about the structure-activity relationship. In this review, the recent applications of the in situ/operando spectroscopy methodology on metal catalysts with reducible metal oxides as supports are summarized.
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49
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Lee T, Lee YJ, Palotás K, Lee G, Stampfl C, Soon A. Polymorphic expressions of ultrathin oxidic layers of Mo on Au(111). NANOSCALE 2019; 11:6023-6035. [PMID: 30869099 DOI: 10.1039/c8nr10278c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Ultrathin oxidic layers of Mo (i.e. O/Mo) on the Au(111) substrate are investigated using first-principles density-functional theory calculations. Various polymorphic structural models of these O/Mo layers are proposed and compared with previous experimental results - covering both spectroscopic and microscopic approaches of characterization. We find that, through the control of metal-oxygen coordination in these ultrathin oxidic O/Mo films on Au(111), the oxidation state of Mo atoms in the O/Mo layers can be modulated and reduced without intentional creation of oxygen vacancies. This is also assisted by a charge transfer mechanism from the Au substrate to these oxidic films, providing a direct means to tune the surface electronic properties of ultrathinoxide films on metal substrates.
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Affiliation(s)
- Taehun Lee
- Department of Materials Science & Engineering and Center for Artificial Synesthesia Materials Discovery, Yonsei University, Seoul 03722, Republic of Korea.
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50
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Baletto F. Structural properties of sub-nanometer metallic clusters. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:113001. [PMID: 30562724 DOI: 10.1088/1361-648x/aaf989] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
At the nanoscale, the investigation of structural features becomes fundamental as we can establish relationships between cluster geometries and their physicochemical properties. The peculiarity lies in the variety of shapes often unusual and far from any geometrical and crystallographic intuition clusters can assume. In this respect, we should treat and consider nanoparticles as a new form of matter. Nanoparticle structures depend on their size, chemical composition, ordering, as well as external conditions e.g. synthesis method, pressure, temperature, support. On top of that, at finite temperatures nanoparticles can fluctuate among different structures, opening new and exciting horizons for the design of optimal nanoparticles for advanced applications. This article aims to overview geometrical features of transition metal clusters and of their various rearrangements.
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Affiliation(s)
- Francesca Baletto
- Physics Department, King's College London, WC2R 2LS, London, United Kingdom
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