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Aleinikava D, Jellinek J. Analysis of Dynamical Peculiarities in Nanoalloys at Subsystems Level: Dynamical Degrees of Freedom, Temperature Differences, and the Chameleon Effect. Chemphyschem 2023; 24:e202300184. [PMID: 37582049 DOI: 10.1002/cphc.202300184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 08/13/2023] [Accepted: 08/14/2023] [Indexed: 08/17/2023]
Abstract
A novel analysis of the dynamical behavior of nanoalloy systems, as represented by model Ni/Al 13-atom clusters, over a broad range of energies that cover the stage-wise transition of the systems from their solid-like to liquid-like state is presented. Conceptually, the analysis is rooted in partitioning the systems into judiciously chosen subsystems and characterizing the latter in terms of subsystem-specific dynamical descriptors that include dynamical degrees of freedom, root-mean-square bond-length fluctuation, and element-specific subsystem temperature. The analysis reveals a host of intriguing new peculiarities in the dynamical behavior of the Ni/Al 13-mers, among which are what we call the chameleon effect and the difference in the temperatures of the Ni and Al subsystems at high energies, a difference that strongly depends on the cluster composition and also changes with energy. These do not have an analog in pure Ni13 and Al13 and are explained in terms of the coupled effects of the difference between the masses of the Ni and Al atoms (the mass effect) and of the difference in the anharmonicity of the overall interaction potential as experienced by the Ni and Al subsystems of the clusters (the potential effect).
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Affiliation(s)
- Darya Aleinikava
- Department of Physical Sciences, Benedictine University Lisle, Illinois, 60532, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory Lemont, Illinois, 60439, USA
| | - Julius Jellinek
- Chemical Sciences and Engineering Division, Argonne National Laboratory Lemont, Illinois, 60439, USA
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2
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Raju RK, Sivakumar S, Wang X, Ulissi ZW. Cluster-MLP: An Active Learning Genetic Algorithm Framework for Accelerated Discovery of Global Minimum Configurations of Pure and Alloyed Nanoclusters. J Chem Inf Model 2023; 63:6192-6197. [PMID: 37824704 PMCID: PMC10598790 DOI: 10.1021/acs.jcim.3c01431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Indexed: 10/14/2023]
Abstract
Structural characterization of nanoclusters is one of the major challenges in nanocluster modeling owing to the multitude of possible configurations of arrangement of cluster atoms. The genetic algorithm (GA), a class of evolutionary algorithms based on the principles of natural evolution, is a commonly employed search method for locating the global minimum configuration of nanoclusters. Although a GA search at the DFT level is required for the accurate description of a potential energy surface to arrive at the correct global minimum configuration of nanoclusters, computationally expensive DFT evaluation of the significantly larger number of cluster geometries limits its practicability. Recently, machine learning potentials (MLP) that are learned from DFT calculations gained significant attention as computationally cheap alternative options that provide DFT level accuracy. As the accuracy of the MLP predictions is dependent on the quality and quantity of the training DFT data, active learning (AL) strategies have gained significant momentum to bypass the need of large and representative training data. In this application note, we present Cluster-MLP, an on-the-fly active learning genetic algorithm framework that employs the Flare++ machine learning potential (MLP) for accelerating the GA search for global minima of pure and alloyed nanoclusters. We have used a modified version the Birmingham parallel genetic algorithm (BPGA) for the nanocluster GA search which is then incorporated into distributed evolutionary algorithms in Python (DEAP), an evolutionary computational framework for fast prototyping or technical experiments. We have shown that the incorporation of the AL framework in the BPGA significantly reduced the computationally expensive DFT calculations. Moreover, we have shown that both the AL-GA and DFT-GA predict the same global minima for all the clusters we tested.
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Affiliation(s)
- Rajesh K. Raju
- Chemical
Engineering Department, Carnegie Mellon
University, Pittsburgh, Pennsylvania 15217, United States
- School
of Chemistry, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Saurabh Sivakumar
- Chemical
Engineering Department, Carnegie Mellon
University, Pittsburgh, Pennsylvania 15217, United States
| | - Xiaoxiao Wang
- Chemical
Engineering Department, Carnegie Mellon
University, Pittsburgh, Pennsylvania 15217, United States
| | - Zachary W. Ulissi
- Chemical
Engineering Department, Carnegie Mellon
University, Pittsburgh, Pennsylvania 15217, United States
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3
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Hizi A, Forster GD, Ferrando R, Garreau Y, Coati A, Andreazza-Vignolle C, Andreazza P. Combined atomistic simulations to explore metastability and substrate effects in Ag-Co nanoalloy systems. Faraday Discuss 2023; 242:35-51. [PMID: 36349781 DOI: 10.1039/d2fd00114d] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The Ag/Co nanoalloy system is a model system situated energetically at the limit of stability of the core-shell chemical ordering with respect to a simple phase separation behavior. This makes the system highly susceptible to effects of the environment, such as interaction with a substrate. However, kinetic effects may also be exploited by careful atom-by-atom particle growth that allows to lock in certain out-of-equilibrium configurations, such as off-center, quasi-Janus and even Janus type particles. In this contribution, we explore to what extent out-of-equilibrium structures are due to kinetic effects and the influence of the interaction of the particles with an amorphous carbon substrate by a joint experimental and molecular dynamics study. The simulation set up performed at 300 K and 600 K mimicks the experimental growth process. The substrate deforms the particles, but has also an ordering effect on particle orientation and particle structure. In the case of growth of Ag on Co seeds, particles assume close to equilibrium quasi-Janus structures, while for the deposition of Co on Ag seeds, highly out-of-equilibrium structures with several subsurface Co clusters are obtained.
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Affiliation(s)
- Abir Hizi
- Interfaces, Confinement, Matériaux et Nanostructures (ICMN), Université d'Orléans, CNRS, Orléans, France.
| | - Georg Daniel Forster
- Interfaces, Confinement, Matériaux et Nanostructures (ICMN), Université d'Orléans, CNRS, Orléans, France.
| | | | | | | | | | - Pascal Andreazza
- Interfaces, Confinement, Matériaux et Nanostructures (ICMN), Université d'Orléans, CNRS, Orléans, France.
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4
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Ojha A, Megha, Bulusu SS, Banerjee A. Structure and dynamics of 38-atom Ag-Pt nanoalloys using ANN based-interatomic potential. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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5
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Yao CH, Li YD. Evolution of the structural and electronic properties of AlnP13−n (n = 0–13) clusters. Theor Chem Acc 2022. [DOI: 10.1007/s00214-022-02912-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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6
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Sathish K, Manjunatha H, Vidya Y, Sridhar K, Seenappa L, Reddy BC, Raj SAC, Manjunatha S, Gupta PD, Munirathnam R. Investigations on Radiation Shielding properties of Leadaluminoborate nanocomposite. Progress in Nuclear Energy 2022; 150:104310. [DOI: 10.1016/j.pnucene.2022.104310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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7
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Barrionuevo MVF, Andrés J, San-Miguel MA. A Theoretical Study on the Structural, Electronic, and Magnetic Properties of Bimetallic Pt13−nNin (N = 0, 3, 6, 9, 13) Nanoclusters to Unveil the Catalytic Mechanisms for the Water-Gas Shift Reaction. Front Chem 2022; 10:852196. [PMID: 35518715 PMCID: PMC9063635 DOI: 10.3389/fchem.2022.852196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 02/21/2022] [Indexed: 11/13/2022] Open
Abstract
In this work, first-principles calculations by using density functional theory at the GFN-xTB level, are performed to investigate the relative stability and structural, electronic, and magnetic properties of bimetallic Pt13−nNin (n = 0, 3, 6, 9, 13) nanoclusters by using corrected Hammer and Nørskov model. In addition, by employing the reaction path and the energetic span models, the energy profile and the turnover frequency are calculated to disclose the corresponding reaction mechanism of the water-gas shift reaction catalyzed by these nanoclusters. Our findings render that Ni causes an overall shrinking of the nanocluster’s size and misalignment of the spin channels, increasing the magnetic nature of the nanoclusters. Pt7Ni6 nanocluster is the most stable as a result of the better coupling between the Pt and Ni d-states. Pt4Ni9 maintains its structure over the reaction cycle, with a larger turnover frequency value than Pt7Ni6. On the other hand, despite Pt10Ni3 presenting the highest value of turnover frequency, it suffers a strong structural deformation over the completion of a reaction cycle, indicating that the catalytic activity can be altered.
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Affiliation(s)
- Manoel Victor Frutuoso Barrionuevo
- UNICAMP Materials Simulation Lab, Institute of Chemistry, Department of Physical-Chemistry, University of Campinas, Campinas, Brazil
- Química Teórica y Computacional, Department de Química Física i Analítica, Universitat Jaume I, Castellón de la Plana, Spain
| | - Juan Andrés
- Química Teórica y Computacional, Department de Química Física i Analítica, Universitat Jaume I, Castellón de la Plana, Spain
- *Correspondence: Juan Andrés, ; Miguel Angel San-Miguel,
| | - Miguel Angel San-Miguel
- UNICAMP Materials Simulation Lab, Institute of Chemistry, Department of Physical-Chemistry, University of Campinas, Campinas, Brazil
- *Correspondence: Juan Andrés, ; Miguel Angel San-Miguel,
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8
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Geoffrion LD, José-Yacaman M, Lehr A, Yang SZ, Sanchez J, Velazquez-Salazar JJ, Guisbiers G. Substitutional-interstitial structural transition in Cu-Pt nano-alloys. Nanoscale Adv 2021; 3:3746-3751. [PMID: 36133014 PMCID: PMC9418689 DOI: 10.1039/d1na00204j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/27/2021] [Indexed: 06/16/2023]
Abstract
Copper-platinum alloys are important binary alloys in catalysis. In this communication, we demonstrate that it is possible to preserve the thermal properties of platinum with a copper-platinum alloy by converting the substitutional alloy into an interstitial one. This conversion occurs when the size of the copper-platinum system is reduced down to the nanoscale. The size-dependent phase diagram of Cu-Pt for a spherical nanoparticle is calculated at various sizes (50, 10 and 5 nm) demonstrating that Cu-Pt alloyed nanoparticles can be formed all over the composition range. Experimentally, the electron microscopy characterization of copper-platinum alloyed nanoparticles synthesized by wet chemistry supports the predicted structural transition.
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Affiliation(s)
- Luke D Geoffrion
- Department of Physics & Astronomy, University of Arkansas at Little Rock 2801 South University Avenue Little Rock AR 72204 USA
| | - Miguel José-Yacaman
- Department of Applied Physics & Materials Science, Northern Arizona University 624 S. Knowles Drive Flagstaff AZ 86011 USA
| | - Alexander Lehr
- Department of Applied Physics & Materials Science, Northern Arizona University 624 S. Knowles Drive Flagstaff AZ 86011 USA
| | - Shi-Ze Yang
- Eyring Materials Center, Arizona State University 300 E University Drive Tempe AZ 85287 USA
| | - John Sanchez
- Department of Applied Physics & Materials Science, Northern Arizona University 624 S. Knowles Drive Flagstaff AZ 86011 USA
| | - J Jesus Velazquez-Salazar
- Department of Applied Physics & Materials Science, Northern Arizona University 624 S. Knowles Drive Flagstaff AZ 86011 USA
| | - Grégory Guisbiers
- Department of Physics & Astronomy, University of Arkansas at Little Rock 2801 South University Avenue Little Rock AR 72204 USA
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9
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Rybaltovsky A, Epifanov E, Khmelenin D, Shubny A, Zavorotny Y, Yusupov V, Minaev N. Two Approaches to the Laser-Induced Formation of Au/Ag Bimetallic Nanoparticles in Supercritical Carbon Dioxide. Nanomaterials (Basel) 2021; 11:1553. [PMID: 34208329 DOI: 10.3390/nano11061553] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 01/05/2023]
Abstract
Two approaches are proposed for the synthesis of bimetallic Au/Ag nanoparticles, using the pulsed laser ablation of a target consisting of gold and silver plates in a medium of supercritical carbon dioxide. The differences between the two approaches related to the field of “green chemistry” are in the use of different geometric configurations and different laser sources when carrying out the experiments. In the first configuration, the Ag and Au targets are placed side-by-side vertically on the side wall of a high-pressure reactor and the ablation of the target plates occurs alternately with a stationary “wide” horizontal beam with a laser pulse repetition rate of 50 Hz. In the second configuration, the targets are placed horizontally at the bottom of a reactor and the ablation of their parts is carried out by scanning from above with a vertical “narrow” laser beam with a pulse repetition rate of 60 kHz. The possibility of obtaining Ag/Au alloy nanoparticles is demonstrated using the first configuration, while the possibility of obtaining “core–shell” bimetallic Au/Ag nanoparticles with a gold core and a silver shell is demonstrated using the second configuration. A simple model is proposed to explain the obtained results.
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10
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Andreazza P, Lemoine A, Coati A, Nelli D, Ferrando R, Garreau Y, Creuze J, Andreazza-Vignolle C. From metastability to equilibrium during the sequential growth of Co-Ag supported clusters: a real-time investigation. Nanoscale 2021; 13:6096-6104. [PMID: 33683240 DOI: 10.1039/d0nr08862e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Atomic motions and morphological evolution of growing Co-Ag nanoparticles are followed in situ and in real time, by wide and small angle X-ray scattering obtained simultaneously in grazing incidence geometry (GISAXS and GIWAXS), in single or multi-wavelength anomalous modes. The structural analysis of the experimental data is performed with the aid of equilibrium Monte Carlo simulations and of molecular-dynamics simulations of nanoparticle growth. Growth is performed by depositing Co atoms above preformed Ag nanoparticles. This growth procedure is strongly out of equilibrium, because Ag tends to surface segregation, and generates complex growth sequences. The real time analysis of the growth allows to follow the nanoparticle evolution pathways almost atom-by-atom, determining the key mechanisms during Co deposition: starting with the incorporation of Co atoms in sub-surface positions, to the off-center Co domain formation, then by which the nanoparticles finally approach their equilibrium quasi-Janus then core-shell structures.
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Affiliation(s)
- P Andreazza
- Interfaces, Confinement, Matériaux et Nanostructures, ICMN, Université d'Orléans, CNRS, Orléans, France.
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11
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Zhang H, Pan J, Zhou Q, Xia F. Nanometal Thermocatalysts: Transformations, Deactivation, and Mitigation. Small 2021; 17:e2005771. [PMID: 33458963 DOI: 10.1002/smll.202005771] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/16/2020] [Indexed: 06/12/2023]
Abstract
Nanometals have been proven to be efficient thermocatalysts in the last decades. Their enhanced catalytic activity and tunable functionalities make them intriguing candidates for a wide range of catalytic applications, such as gaseous reactions and compound synthesis/decomposition. On the other hand, the enhanced specific surface energy and reactivity of nanometals can lead to configuration transformation and thus catalytic deactivation during the synthesis and catalysis, which largely undermines the activity and service time, thereby calling for urgent research effort to understand the deactivating mechanisms and develop efficient mitigating methods. Herein, the recent progress in understanding the configuration transformation-induced catalytic deactivation within nanometals is reviewed. The major pathways of configuration transformations, and their kinetics controlled by the environmental factors are presented. The approaches toward mitigating the transformation-induced deactivation are also presented. Finally, a perspective on the future academic approaches toward in-depth understanding of the kinetics of the deactivation of nanometals is proposed.
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Affiliation(s)
- Hanlei Zhang
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, No. 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei, 430078, P. R. China
| | - Jing Pan
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, No. 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei, 430078, P. R. China
| | - Qitao Zhou
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, No. 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei, 430078, P. R. China
| | - Fan Xia
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, No. 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, Hubei, 430078, P. R. China
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12
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SÜMER A. Effects of composition on catalytic activities of molybdenum doped platinum nanoparticles. Turk J Chem 2020; 44:1016-1030. [PMID: 33488209 PMCID: PMC7751935 DOI: 10.3906/kim-2001-63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 05/31/2020] [Indexed: 11/03/2022] Open
Abstract
The physical and chemical properties of bimetallic nanoparticles can be optimized by tuning the particle composition. In this study, we identified CO adsorption and dissociation energetics on five Pt-Mo nanoparticles at different concentrations, the lowest energy Pt7, Pt6Mo, Pt5Mo2, Pt4Mo3, and Mo7 clusters. We have shown that the CO adsorption and dissociation energies and preferred CO adsorption sites are largely dependent on the composition of the nanoparticles. As the Mo concentration increases, the strength of the C-O internal bond in the adsorption complex decreases, as indicated by a decrease in the C-O stretching frequency. Also, more Mo sites in the nanoparticle become available for CO adsorption, and the preferred CO adsorption site switches from Pt to Mo. For these reasons, dissociation of CO is energetically favorable on Pt4Mo3 and Mo7. On both compositions, we have shown that the dissociation paths begin with CO adsorbed on a Mo site in a multifold configuration, in particular in a tilted configuration. These findings provide insight on the effects of the composition on the chemical and catalytical properties of Pt-Mo nanoparticles, thereby guiding future experiments on the synthesis of nanoparticles, especially those that may be suitable for various desired applications containing CO.
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Affiliation(s)
- Aslıhan SÜMER
- Faculty of Pharmacy, University of Health Sciences Turkey, İstanbulTurkey
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13
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Abstract
The nickel-cobalt system is an important alloy in nanotechnology because of its ferromagnetic properties, high thermal stability and shape memory effect. At the nanoscale, its physico-chemical properties become size-, shape- and composition- dependent. However, those properties are still mostly unknown at the nanoscale. Therefore, this manuscript fills this gap in knowledge. Indeed, when the size of the alloy is reduced, the entire phase diagram undergoes a vertical shift downward to lower temperatures, and a tilt caused by a larger size effect affecting cobalt than nickel. Among the most commonly observed shapes, the thermal stability of nickel-cobalt nanoparticles was determined as a function of their size and composition. Furthermore, the ferromagnetic-paramagnetic phase transition and martensitic transformation for those shapes were calculated as a function of the nickel-cobalt alloy composition. As expected, the ferromagnetic and martensitic regions shrunk at the nanoscale; but the martensitic transformation was less affected by size effects compared to magnetic and thermal (melting) transitions.
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Affiliation(s)
- Grégory Guisbiers
- Department of Physics and Astronomy, University of Arkansas at Little Rock, 2801 South University Avenue, Little Rock, AR 72204, United States of America
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14
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Christensen DB, Mortensen RL, Kramer S, Kegnæs S. Study of CoCu Alloy Nanoparticles Supported on MOF-Derived Carbon for Hydrosilylation of Ketones. Catal Letters 2019. [DOI: 10.1007/s10562-019-03065-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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15
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Soleimani Zohr Shiri M, Henderson W, Mucalo MR. A Review of The Lesser-Studied Microemulsion-Based Synthesis Methodologies Used for Preparing Nanoparticle Systems of The Noble Metals, Os, Re, Ir and Rh. Materials (Basel) 2019; 12:E1896. [PMID: 31212850 PMCID: PMC6631116 DOI: 10.3390/ma12121896] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/10/2019] [Accepted: 06/10/2019] [Indexed: 12/21/2022]
Abstract
This review focuses on the recent advances in the lesser-studied microemulsion synthesis methodologies of the following noble metal colloid systems (i.e., Os, Re, Ir, and Rh) using either a normal or reverse micelle templating system. The aim is to demonstrate the utility and potential of using this microemulsion-based approach to synthesize these noble metal nanoparticle systems. Firstly, some fundamentals and important factors of the microemulsion synthesis methodology are introduced. Afterward, a review of the investigations on the microemulsion syntheses of Os, Re, Ir, and Rh nanoparticle (NP) systems (in all forms, viz., metallic, oxide, mixed-metal, and discrete molecular complexes) is presented for work published in the last ten years. The chosen noble metals are traditionally very reactive in nanosized dimensions and have a strong tendency to aggregate when prepared via other methods. Also, the particle size and particle size distribution of these colloids can have a significant impact on their catalytic performance. It is shown that the microemulsion approach has the capability to better stabilize these metal colloids and can control the size of the synthesized NPs. This generally leads to smaller particles and higher catalytic activity when they are tested in applications.
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Affiliation(s)
| | - William Henderson
- School of Science, University of Waikato, Hamilton 3240, New Zealand.
| | - Michael R Mucalo
- School of Science, University of Waikato, Hamilton 3240, New Zealand.
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16
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Pavlov J, Attygalle AB. Gold Nanoparticles (AuNPs) as Reactive Matrix for Detection of Trace Levels of HCN in Air by Laser Desorption/Ionization Mass Spectrometry (LDI-MS). J Am Soc Mass Spectrom 2019; 30:806-813. [PMID: 30847834 DOI: 10.1007/s13361-018-02131-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 12/28/2018] [Indexed: 06/09/2023]
Abstract
Under direct laser desorption/ionization mass spectrometric conditions, the irradiation of target spots made of gold nanoparticle residues generates a series of peaks at m/z 197, 394, 591… representing Aun- ions (n = 1-3). In contrast, spectra recorded from gold nanoparticles directly mixed with an alkali cyanide exhibited an additional peak at m/z 249, indicating an abundant generation of gaseous [Au(CN)2]- ions upon irradiation. The relative intensity of the m/z 249 peak surged when the amount of cyanide in the mixture was increased. Most remarkably, a peak at m/z 249 was observed even from neat AuNPs upon irradiation, if a nearby spot, which was not irradiated, happened to bear a cyanide sample. We postulated that traces of HCN emanating from the headspace of aqueous cyanide solution during the sample-plate preparation is sufficient to convert gold to AuCN, which is subsequently detected as [Au(CN)2]-. Further experiments demonstrated that the relative intensity of the m/z 249 peak diminishes exponentially as the AuNP spot becomes more distant from the putative HCN source. Eventually, the method was developed as an efficient procedure to detect HCN or alkali cyanides. Using KCN, the detection limits were determined to be below 10 pg of CN- per spot. The method also demonstrated that, upon crushing, the seeds or roots of certain fruits and vegetables such as apple, peach, radish, and cassava, but not carrot, release HCN in amounts detectable by this method. Graphical Abstract.
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Affiliation(s)
- Julius Pavlov
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Athula B Attygalle
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.
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17
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Machado T, Macedo NG, Assis M, Doñate-Buendia C, Mínguez-Vega G, Teixeira MM, Foggi CC, Vergani CE, Beltrán-Mir H, Andrés J, Cordoncillo E, Longo E. From Complex Inorganic Oxides to Ag-Bi Nanoalloy: Synthesis by Femtosecond Laser Irradiation. ACS Omega 2018; 3:9880-9887. [PMID: 31459116 PMCID: PMC6644639 DOI: 10.1021/acsomega.8b01264] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/13/2018] [Indexed: 05/17/2023]
Abstract
Bimetallic nanoalloys with a wide variety of structures and compositions have been fabricated through many diverse techniques. Generally, various steps and chemicals are involved in their fabrication. In this study, the synthesis of Ag-Bi nanoalloys by femtosecond laser irradiation of an inorganic oxide Ag2WO4/NaBiO3 target without any chemicals like reducing agents or solvent is presented. The interaction between these materials and the ultrashort pulse of light allows the migration of Ag and Bi atoms from the crystal lattice to the particles surfaces and then to the plasma plume, where the reduction of the positively charged Ag and Bi species in their respective metallic species takes place. Subsequently, the controlled nucleation and growth of the Ag-Bi alloyed nanoparticles occurs in situ during the irradiation process in air. Although at the bulk level, these elements are highly immiscible, it was experimentally demonstrated that at nanoscale, the Ag-Bi nanoalloy can assume a randomly mixed structure with up to 6 ± 1 atom % of Bi solubilized into the face-centered cubic structure of Ag. Furthermore, the Ag-Bi binary system possesses high antibacterial activity against Staphylococcus aureus (methicillin-resistant and methicilin-susceptible), which is interesting for potential antimicrobial applications, consequently increasing their range of applicability. The present results provide potential insights into the structures formed by the Ag-Bi systems at the nanoscale and reveal a new processing method where complex inorganic oxides can be used as precursors for the controlled synthesis of alloyed bimetallic nanoparticles.
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Affiliation(s)
- Thales
R. Machado
- Departamento
de Química, CDMF, Universidade Federal
de São Carlos (UFSCar), São Carlos 13565-905, São Paulo, Brazil
| | - Nadia G. Macedo
- Departamento
de Química, CDMF, Universidade Federal
de São Carlos (UFSCar), São Carlos 13565-905, São Paulo, Brazil
| | - Marcelo Assis
- Departamento
de Química, CDMF, Universidade Federal
de São Carlos (UFSCar), São Carlos 13565-905, São Paulo, Brazil
| | - Carlos Doñate-Buendia
- Institut de Noves Tecnologies de la Imatge (INIT),
GROC, Departament
de Química
Inorgànica i Orgànica, and Departament de Química Física
i Analítica, Universitat Jaume I
(UJI), Castellón de la Plana 12071, Castelló, Spain
| | - Gladys Mínguez-Vega
- Institut de Noves Tecnologies de la Imatge (INIT),
GROC, Departament
de Química
Inorgànica i Orgànica, and Departament de Química Física
i Analítica, Universitat Jaume I
(UJI), Castellón de la Plana 12071, Castelló, Spain
| | - Mayara M. Teixeira
- Departamento
de Química, CDMF, Universidade Federal
de São Carlos (UFSCar), São Carlos 13565-905, São Paulo, Brazil
| | - Camila C. Foggi
- Departamento
de Química, CDMF, Universidade Federal
de São Carlos (UFSCar), São Carlos 13565-905, São Paulo, Brazil
| | - Carlos E. Vergani
- Faculdade
de Odontologia, Universidade Estadual Paulista
(UNESP), Araraquara 14801-385, São Paulo, Brazil
| | - Héctor Beltrán-Mir
- Institut de Noves Tecnologies de la Imatge (INIT),
GROC, Departament
de Química
Inorgànica i Orgànica, and Departament de Química Física
i Analítica, Universitat Jaume I
(UJI), Castellón de la Plana 12071, Castelló, Spain
| | - Juan Andrés
- Institut de Noves Tecnologies de la Imatge (INIT),
GROC, Departament
de Química
Inorgànica i Orgànica, and Departament de Química Física
i Analítica, Universitat Jaume I
(UJI), Castellón de la Plana 12071, Castelló, Spain
| | - Eloisa Cordoncillo
- Institut de Noves Tecnologies de la Imatge (INIT),
GROC, Departament
de Química
Inorgànica i Orgànica, and Departament de Química Física
i Analítica, Universitat Jaume I
(UJI), Castellón de la Plana 12071, Castelló, Spain
| | - Elson Longo
- Departamento
de Química, CDMF, Universidade Federal
de São Carlos (UFSCar), São Carlos 13565-905, São Paulo, Brazil
- E-mail:
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De Souza DG, Cezar HM, Rondina GG, de Oliveira MF, Da Silva JLF. A basin-hopping Monte Carlo investigation of the structural and energetic properties of 55- and 561-atom bimetallic nanoclusters: the examples of the ZrCu, ZrAl, and CuAl systems. J Phys Condens Matter 2016; 28:175302. [PMID: 27045947 DOI: 10.1088/0953-8984/28/17/175302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report a basin-hopping Monte Carlo investigation within the embedded-atom method of the structural and energetic properties of bimetallic ZrCu, ZrAl, and CuAl nanoclusters with 55 and 561 atoms. We found that unary Zr55, Zr561, Cu55, Cu561, Al55, and Al561 systems adopt the well known compact icosahedron (ICO) structure. The excess energy is negative for all systems and compositions, which indicates an energetic preference for the mixing of both chemical species. The ICO structure is preserved if a few atoms of the host system are replaced by different species, however, the composition limit in which the ICO structure is preserved depends on both the host and new chemical species. Using several structural analyses, three classes of structures, namely ideal ICO, nearly ICO, and distorted ICO structures, were identified. As the amounts of both chemical species change towards a more balanced composition, configurations far from the ICO structure arise and the dominant structures are nearly spherical, which indicates a strong minimization of the surface energy by decreasing the number of atoms with lower coordination on the surface. The average bond lengths follow Vegard's law almost exactly for ZrCu and ZrAl, however, this is not the case for CuAl. Furthermore, the radial distribution allowed us to identify the presence of an onion-like behavior in the surface of the 561-atom CuAl nanocluster with the Al atoms located in the outermost surface shell, which can be explained by the lower surface energies of the Al surfaces compared with the Cu surfaces. In ZrCu and ZrAl the radial distribution indicates a nearly homogeneous distribution for the chemical species, however, with a slightly higher concentration of Al atoms on the ZrAl surface, which can also be explained by the lower surface energy.
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Affiliation(s)
- Douglas G De Souza
- Department of Materials Engineering, São Carlos School of Engineering, University of São Paulo, PO Box 1100, 13563-120, São Carlos, SP, Brazil
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Guisbiers G, Mendoza-Cruz R, Bazán-Díaz L, Velázquez-Salazar JJ, Mendoza-Perez R, Robledo-Torres JA, Rodriguez-Lopez JL, Montejano-Carrizales JM, Whetten RL, José-Yacamán M. Electrum, the Gold-Silver Alloy, from the Bulk Scale to the Nanoscale: Synthesis, Properties, and Segregation Rules. ACS Nano 2016; 10:188-98. [PMID: 26605557 PMCID: PMC4734609 DOI: 10.1021/acsnano.5b05755] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 11/20/2015] [Indexed: 05/26/2023]
Abstract
The alloy Au-Ag system is an important noble bimetallic phase, both historically (as "Electrum") and now especially in nanotechnology, as it is applied in catalysis and nanomedicine. To comprehend the structural characteristics and the thermodynamic stability of this alloy, a knowledge of its phase diagram is required that considers explicitly its size and shape (morphology) dependence. However, as the experimental determination remains quite challenging at the nanoscale, theoretical guidance can provide significant advantages. Using a regular solution model within a nanothermodynamic approach to evaluate the size effect on all the parameters (melting temperature, melting enthalpy, and interaction parameters in both phases), the nanophase diagram is predicted. Besides an overall shift downward, there is a "tilting" effect on the solidus-liquidus curves for some particular shapes exposing the (100) and (110) facets (cube, rhombic dodecahedron, and cuboctahedron). The segregation calculation reveals the preferential presence of silver at the surface for all the polyhedral shapes considered, in excellent agreement with the latest transmission electron microscopy observations and energy dispersive spectroscopy analysis. By reviewing the nature of the surface segregated element of different bimetallic nanoalloys, two surface segregation rules, based on the melting temperatures and surface energies, are deduced. Finally, the optical properties of Au-Ag nanoparticles, calculated within the discrete dipole approximation, show the control that can be achieved in the tuning of the local surface plasmon resonance, depending of the alloy content, the chemical ordering, the morphology, the size of the nanoparticle, and the nature of the surrounding environment.
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Affiliation(s)
- Grégory Guisbiers
- Department
of Physics & Astronomy, University of
Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United
States
| | - Rubén Mendoza-Cruz
- Department
of Physics & Astronomy, University of
Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United
States
- Institute
of Physics, Universidad Nacional Autónoma
de Mexico, A. P. 20-364
Distrito Federal C.P. 01000 Mexico City, Mexico
| | - Lourdes Bazán-Díaz
- Department
of Physics & Astronomy, University of
Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United
States
- Institute
of Physics, Universidad Nacional Autónoma
de Mexico, A. P. 20-364
Distrito Federal C.P. 01000 Mexico City, Mexico
| | - J. Jesús Velázquez-Salazar
- Department
of Physics & Astronomy, University of
Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United
States
| | - Rafael Mendoza-Perez
- Department
of Physics & Astronomy, University of
Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United
States
| | - José Antonio Robledo-Torres
- Advanced Materials
Department, IPICYT, A.C., Camino Presa San José 2055, Lomas 4a Secc. 78216 San Luis Potosi, Mexico
| | - José-Luis Rodriguez-Lopez
- Advanced Materials
Department, IPICYT, A.C., Camino Presa San José 2055, Lomas 4a Secc. 78216 San Luis Potosi, Mexico
| | | | - Robert L. Whetten
- Department
of Physics & Astronomy, University of
Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United
States
| | - Miguel José-Yacamán
- Department
of Physics & Astronomy, University of
Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United
States
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Ferrando R. Introduction. Structure and Properties of Nanoalloys. Elsevier; 2016. pp. 1-11. [DOI: 10.1016/b978-0-08-100212-4.00001-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Aslan M, Davis JBA, Johnston RL. Global optimization of small bimetallic Pd–Co binary nanoalloy clusters: a genetic algorithm approach at the DFT level. Phys Chem Chem Phys 2016; 18:6676-82. [DOI: 10.1039/c6cp00342g] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The global optimisation of small bimetallic PdCo binary nanoalloys are systematically investigated using the Birmingham Cluster Genetic Algorithm (BCGA).
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Affiliation(s)
- Mikail Aslan
- Department of Metallurgical and Materials Engineering
- Gaziantep University
- Gaziantep
- Turkey
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23
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Chaves AS, Piotrowski MJ, Guedes-Sobrinho D, Da Silva JLF. Theoretical Investigation of the Adsorption Properties of CO, NO, and OH on Monometallic and Bimetallic 13-Atom Clusters: The Example of Cu13, Pt7Cu6, and Pt13. J Phys Chem A 2015; 119:11565-73. [DOI: 10.1021/acs.jpca.5b08330] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anderson S. Chaves
- São
Carlos Institute of Chemistry, University of São Paulo, P.O. Box 780, 13560-970, São Carlos, SP, Brazil
| | - Maurício J. Piotrowski
- Physics
Department, Federal University of Pelotas, P.O. Box 354, 96010-900, Pelotas, RS, Brazil
| | - Diego Guedes-Sobrinho
- São
Carlos Institute of Chemistry, University of São Paulo, P.O. Box 780, 13560-970, São Carlos, SP, Brazil
| | - Juarez L. F. Da Silva
- São
Carlos Institute of Chemistry, University of São Paulo, P.O. Box 780, 13560-970, São Carlos, SP, Brazil
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Zhang M, Wang N, Yang Y, Huang S. Insight into the relationship between structure and magnetic properties in icosahedral Fe n Pt 55−n ( n = 0–55) nanoparticles: DFT approach. J Mol Graph Model 2015; 62:294-302. [DOI: 10.1016/j.jmgm.2015.10.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 10/17/2015] [Accepted: 10/19/2015] [Indexed: 10/22/2022]
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Nasrabadi HT, Abbasi E, Davaran S, Kouhi M, Akbarzadeh A. Bimetallic nanoparticles: Preparation, properties, and biomedical applications. Artificial Cells, Nanomedicine, and Biotechnology 2014; 44:376-80. [DOI: 10.3109/21691401.2014.953632] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Dietrich PJ, Wu T, Sumer A, Dumesic JA, Jellinek J, Delgass WN, Ribeiro FH, Miller JT. Aqueous Phase Glycerol Reforming with Pt and PtMo Bimetallic Nanoparticle Catalysts: The Role of the Mo Promoter. Top Catal 2013. [DOI: 10.1007/s11244-013-0115-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abazari R, Heshmatpour F, Balalaie S. Pt/Pd/Fe Trimetallic Nanoparticle Produced via Reverse Micelle Technique: Synthesis, Characterization, and Its Use as an Efficient Catalyst for Reductive Hydrodehalogenation of Aryl and Aliphatic Halides under Mild Conditions. ACS Catal 2012. [DOI: 10.1021/cs300507a] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Reza Abazari
- Department of chemistry, Faculty of Science, K.N.Toosi University of Technology, P.O. Box 16315-1618,
Tehran, 15418, Islamic Republic of Iran
| | - Felora Heshmatpour
- Department of chemistry, Faculty of Science, K.N.Toosi University of Technology, P.O. Box 16315-1618,
Tehran, 15418, Islamic Republic of Iran
| | - Saeed Balalaie
- Department of chemistry, Faculty of Science, K.N.Toosi University of Technology, P.O. Box 16315-1618,
Tehran, 15418, Islamic Republic of Iran
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Negreiros FR, Taherkhani F, Parsafar G, Caro A, Fortunelli A. Kinetics of chemical ordering in a Ag-Pt nanoalloy particle via first-principles simulations. J Chem Phys 2012. [DOI: 10.1063/1.4759507] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Baletto F. Modelling Janus Nanoparticles. Metal Clusters and Nanoalloys. New York: Springer; 2013. pp. 243-73. [DOI: 10.1007/978-1-4614-3643-0_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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32
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Dietrich PJ, Lobo-lapidus RJ, Wu T, Sumer A, Akatay MC, Fingland BR, Guo N, Dumesic JA, Marshall CL, Stach E, Jellinek J, Delgass WN, Ribeiro FH, Miller JT. Aqueous Phase Glycerol Reforming by PtMo Bimetallic Nano-Particle Catalyst: Product Selectivity and Structural Characterization. Top Catal 2012; 55:53-69. [DOI: 10.1007/s11244-012-9775-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Li PY, Cao ZH, Meng XK. Facile synthesis of superparamagnetic Ni–Fe ultrafine nanoalloy nanoparticles with equilibrium ordered phase structure via a sol–gel process. Dalton Trans 2012; 41:12101-5. [DOI: 10.1039/c2dt31484c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Affiliation(s)
- Habib ur Rehman
- Physical and Theoretical Chemistry, University of Saarland, 66123 Saarbrücken, Germany
| | - Michael Springborg
- Physical and Theoretical Chemistry, University of Saarland, 66123 Saarbrücken, Germany
| | - Yi Dong
- Physical and Theoretical Chemistry, University of Saarland, 66123 Saarbrücken, Germany
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Yamauchi M, Tsukuda T. Production of an ordered (B2) CuPd nanoalloy by low-temperature annealing under hydrogen atmosphere. Dalton Trans 2011; 40:4842-5. [DOI: 10.1039/c0dt01632b] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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37
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Yu R, Chen W, Cheng ZY, Li YD, Zhu J. Multishell intermetallic onions by symmetrical configuration of ordered domains. Phys Rev Lett 2010; 105:225501. [PMID: 21231394 DOI: 10.1103/physrevlett.105.225501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Indexed: 05/30/2023]
Abstract
Ordered domains are utilized to construct new nanostructures, i.e., multishell intermetallic onions, which are formed by symmetrical configuration of ordered domains. Through density-functional theory calculations, we have shown that the energy penalties for introducing antiphase boundaries into the nanoparticles are small in some alloy systems compared to typical surface energies, making it feasible to prepare intermetallic onions by tuning surface energies. The unique surface atomic arrangements would provide opportunities for developing novel materials like efficient catalysts.
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Affiliation(s)
- R Yu
- Beijing National Center for Electron Microscopy, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
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Abstract
Photo-ionization mass spectrometry and electric beam deflection experiments were used to study isolated Sn(M)Pb(N) clusters (7 <or=N + M<or= 13 for tin-rich clusters, 7 <or=N + M<or= 15 for lead-rich clusters) in a molecular beam apparatus. The observed mass spectra reveal a broad abundance distribution of the bimetallic clusters in which all possible cluster compositions can be identified within the investigated size ranges. Comparison of the relative cluster intensities between pure tin or lead clusters (Sn(N+M) and Pb(N+M)) and mixed Sn(M)Pb(N) clusters indicate quite similar relative abundance distributions which can be smoothly shifted from one to the other extreme by changing the composition. The mass spectroscopic findings could be explained by assuming a substitution "alloy" formation in the Sn(M)Pb(N) cluster system. In combination, the dielectric properties were determined by passing the bimetallic clusters through an inhomogeneous electric field. The observed polarizabilities are significantly increased for most of the bimetallic clusters. This can be explained in an adiabatic polarization model by the presence of permanent electric dipole moments. These observations demonstrate how the electronic properties are not only crucially influenced by the cluster size but also by the composition of this nanoalloy model system. In addition to the enhanced polarizability, most of the measured beam profiles for tin-rich clusters show detectable beam broadenings due to the permanent dipole moments, in contrast to lead-rich clusters which possess considerable smaller dipole moments. Molecular dynamic simulations of the measured beam profile for Sn(6)Pb(1) taking theoretically calculated isomeric structures and dipole moments into account yields no completely satisfying outcome. Therefore we discuss possible reasons for the discrepancy between experimental and theoretical results.
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Affiliation(s)
- S Heiles
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 20, 64287 Darmstadt, Germany.
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Affiliation(s)
- R. S. Berry
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, and Joint Institute for High Temperatures, Izhorskaya 13/19, Moscow 127412, Russia
| | - B. M. Smirnov
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, and Joint Institute for High Temperatures, Izhorskaya 13/19, Moscow 127412, Russia
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Wang M, Qiu G, Huang X, Du Z, Li Y. Study of the size-dependent properties of Sc(n)Al (n = 1-14) clusters by density-functional theory. J Phys Condens Matter 2009; 21:046004. [PMID: 21715831 DOI: 10.1088/0953-8984/21/4/046004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The geometries, stabilities, and electronic and magnetic properties of Sc(n)Al (n = 1-14) clusters with different spin configurations have been investigated systematically within the framework of the gradient-corrected density-functional theory. Our resulting geometries show that the aluminum atom remains on the surface of clusters with n<9, while it takes up the center of Sc-cage clusters with n≥9. Besides, the doping of Al improves the stability of the host clusters. Maximum peaks are observed for Sc(n)Al clusters at n = 3, 6, 10 and 12 with the size dependent on the second-order energy differences and fragmentation energies, implying that these clusters are relatively more stable. For all the Sc(n)Al clusters studied, we find the charge transfer from Sc to Al sites and the coexistence of ionic and covalent bonding characteristics. The doping of the Al atom induces the magnetic moments of the host clusters decrease except for n = 8 and 14 and the total magnetic moments are quenched at n = 5, 7, 9 and 11.
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Affiliation(s)
- Mei Wang
- Key Laboratory for Special Functional Materials, Ministry of Education, Henan University, Kaifeng 475001, People's Republic of China
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41
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Cao B, Starace AK, Neal CM, Jarrold MF, Núñez S, López JM, Aguado A. Substituting a copper atom modifies the melting of aluminum clusters. J Chem Phys 2008; 129:124709. [DOI: 10.1063/1.2977874] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Li ZH, Truhlar DG. Nanosolids, Slushes, and Nanoliquids: Characterization of Nanophases in Metal Clusters and Nanoparticles. J Am Chem Soc 2008; 130:12698-711. [DOI: 10.1021/ja802389d] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Zhen Hua Li
- Department of Chemistry, Fudan University, Shanghai, 200433, China and Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431
| | - Donald G. Truhlar
- Department of Chemistry, Fudan University, Shanghai, 200433, China and Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431
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