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Mondal P, Rana AK, Saha SK, Subhakumari A, Vasudeva N, Aetukuri NPB, Pandey A. Enhancement of the electrochemical performance of zinc-silver batteries with a gold nano-scaffold. NANOSCALE 2024; 16:13925-13931. [PMID: 38976244 DOI: 10.1039/d4nr02092h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/09/2024]
Abstract
Primary zinc-silver batteries are widely employed in military, aerospace, and marine applications. However, the development of secondary zinc-silver batteries is still a subject of on-going research. For example, these batteries suffer from rapid capacity loss during cycling due to instabilities of the zinc anode and the silver cathode. While there is a large body of work on the Zn anode, there is limited work toward stabilizing the Ag electrode and thereby achieving a long cycle life. In this work, we propose a gold-silver nanostructure where gold acts as a scaffolding material and improves the retention of structural integrity during cell cycling. We show that this nanostructure improves battery capacity as well as capacity retention after 35 cycles. Our work emphasizes the role of nanostructuring in enabling a newer secondary battery chemistry based on existing primary ones.
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Affiliation(s)
- Pritha Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
| | - Ajeet Kumar Rana
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
| | - Subham Kumar Saha
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
| | - Akhila Subhakumari
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
| | - Navyashree Vasudeva
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
| | - Naga Phani B Aetukuri
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
| | - Anshu Pandey
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
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2
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Zhang X, Zhang W, Peng Y. In situinvestigation on melting characteristics of 1D SnCu alloy nanosolder. NANOTECHNOLOGY 2022; 33:305301. [PMID: 35395642 DOI: 10.1088/1361-6528/ac659c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 04/07/2022] [Indexed: 06/14/2023]
Abstract
Nanosoldering can bond various nanomaterials together or connect them with electrodes to form electrical contacts, thus assembling these nanomaterials into functional nanodevices; it is believed to be a promising interconnection technique due to its flexibility, controllability and crucial advantage of avoiding detrimental effects on the nano-objects. In this technique, molten solder as a filler material is introduced between the objects to be joined to form a reliable bond, in which the nanosolder reflow melting is a crucial prerequisite for successful nanosoldering. This work focuses on studying the melting characteristics of one-dimensional 97Sn3Cu nanosolder with low-cost, prominent electrical property and high mechanical reliability, aiming to promote its applications in nanosoldering. The reflow melting of an individual nanosolder has been dynamically observed byin situheating holder in transmission electron microscopy, where the obtained reflow temperature (530 °C) is much higher than its melting temperature (220.4 °C) because of the external oxide layer confinement. Furthermore, the size-dependent melting temperature of nanosolders with various diameters (20-300 nm) has been investigated by both differential scanning calorimetry and theoretical calculation, revealing that the melting temperature decreases as the diameter goes down, especially for the nanosolders in the sub 80 nm range, where the value decreases significantly. The experimental results are in good agreement with the theoretical predictions. These results pointed out here can be readily extended to other nanosolders.
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Affiliation(s)
- Xuan Zhang
- School of Materials and Physics, China University of Mining and Technology, Xuzhou 221116, Jiangsu, People's Republic of China
| | - Wei Zhang
- Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Saclay, CNRS, Orsay F-91405, France
| | - Yong Peng
- School of Materials and Energy, Electron Microscopy Centre of Lanzhou University and Key Laboratory of Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000, People's Republic of China
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3
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Farkaš B, de Leeuw NH. A Perspective on Modelling Metallic Magnetic Nanoparticles in Biomedicine: From Monometals to Nanoalloys and Ligand-Protected Particles. MATERIALS (BASEL, SWITZERLAND) 2021; 14:3611. [PMID: 34203371 PMCID: PMC8269646 DOI: 10.3390/ma14133611] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 12/24/2022]
Abstract
The focus of this review is on the physical and magnetic properties that are related to the efficiency of monometallic magnetic nanoparticles used in biomedical applications, such as magnetic resonance imaging (MRI) or magnetic nanoparticle hyperthermia, and how to model these by theoretical methods, where the discussion is based on the example of cobalt nanoparticles. Different simulation systems (cluster, extended slab, and nanoparticle models) are critically appraised for their efficacy in the determination of reactivity, magnetic behaviour, and ligand-induced modifications of relevant properties. Simulations of the effects of nanoscale alloying with other metallic phases are also briefly reviewed.
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Affiliation(s)
- Barbara Farkaš
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK;
| | - Nora H. de Leeuw
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK;
- School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
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4
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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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5
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Mavrantzas VG, Pratsinis SE. The impact of molecular simulations in gas-phase manufacture of nanomaterials. Curr Opin Chem Eng 2019. [DOI: 10.1016/j.coche.2019.04.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Fernández-Navarro C, Mejía-Rosales S, Tlahuice-Flores A. Structural Diagram of AuxCu1−x Nanoparticles: Dependency of Geometry on Composition and Size. J CLUST SCI 2018. [DOI: 10.1007/s10876-018-1399-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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7
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Ryu MS, Kim HG, Kim HY, Min KS, Kim HJ, Lee HM. Prediction of the glass transition temperature and design of phase diagrams of butadiene rubber and styrene-butadiene rubber via molecular dynamics simulations. Phys Chem Chem Phys 2018; 19:16498-16506. [PMID: 28608873 DOI: 10.1039/c7cp00080d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To prevent car accidents, it is important to evaluate the thermal stability of tire rubbers, such as natural rubber (NR), butadiene rubber (BR), and styrene-butadiene rubber (SBR). Controlling the glass transition temperature (Tg) is the main factor for obtaining desirable thermal stability. Here, we developed an optimized equation for the prediction of the Tg of the various rubber systems using molecular dynamics (MD) simulations. We modeled a random copolymer system, blended monomers, and calculated the Tg of butadiene isomers in each composition. From these results, we designed the Tg contour of ternary cis-trans-vinyl butadiene and derived an equation of Tg for the ternary system. Moreover, we developed an equation to evaluate the pseudo-ternary Tg of quaternary SBR and plotted it. Our results present a novel way of predicting the Tg of ternary BR and quaternary SBR, which is critical for rational tire design with optimized thermal and mechanical stability.
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Affiliation(s)
- Myung Shin Ryu
- Department of Materials Science and Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
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Akbarzadeh H, Shamkhali AN, Mehrjouei E. Ag-Au bimetallic nanoclusters formed from a homogeneous gas phase: a new thermodynamic expression confirmed by molecular dynamics simulation. Phys Chem Chem Phys 2018; 19:3763-3769. [PMID: 28098288 DOI: 10.1039/c6cp08508c] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In this work, two probabilistic and thermodynamic limits for formation of a bimetallic nanocluster from a homogeneous gas phase were obtained in order to investigate the related phenomena using molecular dynamics simulation. Therefore, by application of some simple assumptions from thermodynamics and statistical mechanics, a new expression for composition of the nanocluster was derived which depends only on the initial conditions of the system and one adjustable parameter. This expression can be easily fitted to the results of molecular dynamics and can be used as a measure of the thermodynamic contribution in the cluster formation process. Then, molecular dynamics simulations were performed for several systems containing the same total number of metallic atoms and different concentrations of Ag and Au atoms. The results of this study exhibited that depending on different initial compositions of Ag and Au types, fcc and icosahedral structures are formed. Moreover, increase of the initial Ag concentration leads to products whose compositions are more controlled by probability limits. However, longer simulation times indicated that creation of more thermodynamically favoured nanoclusters depends on the formation of more probable ones in the early stages of the simulation.
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Affiliation(s)
- H Akbarzadeh
- Department of Chemistry, Faculty of Basic Sciences, Hakim Sabzevari University, 96179-76487 Sabzevar, Iran.
| | - A N Shamkhali
- Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, 56199-11367 Ardabil, Iran.
| | - E Mehrjouei
- Department of Chemistry, Faculty of Basic Sciences, Hakim Sabzevari University, 96179-76487 Sabzevar, Iran.
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9
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Akbarzadeh H, Abbaspour M, Mehrjouei E. Phase transition in crown-jewel structured Au-Ir nanoalloys with different shapes: a molecular dynamics study. Phys Chem Chem Phys 2018; 18:25676-25686. [PMID: 27711431 DOI: 10.1039/c6cp04218j] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have studied the melting process for crown-jewel structured Ir55, Ir54Au, Ir43Au12, Ir25Au30, Ir13Au42, and Au55 nanoclusters in the icosahedral, Ir55, Ir54Au, Ir43Au12, Ir19Au36, Ir13Au42, and Au55 nanoclusters in the cuboctahedral, and Ir54, Ir53Au, Ir47Au7, Ir17Au37, Ir7Au47, and Au54 nanoclusters in the decahedral morphologies. We have investigated the different thermodynamic, structural, and dynamical properties for the different nanoclusters in the different structures. Our thermodynamic results indicated that as the concentration of Au atoms in the nanoclusters increases, the absolute value of internal energy, and so the melting points, of the nanoclusters decrease. It is also shown that the Au atoms decrease the melting temperature of the pure cuboctahedral cluster more than that of the other structures. We have also found that the Au atoms were located in favorable positions at the surface sites of nanoalloys. Also, the doping of the Ir nanocluster by Au atoms makes the cluster more stable. It is also found that nanoclusters with different morphologies have almost the same stability. Our structural results indicated that after the melting process, the Au atoms generally tend to lie in the outer shell of the cluster, but the Ir atoms generally tend to lie in the core of the cluster (see the Ir13Au42 and Ir7Au47 nanoclusters, for example). We have also found the interesting result that the Ir7Au47 nanocluster shows a solid-solid transition from a decahedral structure to an icosahedral structure before melting. The Ir43Au12 nanocluster also shows a transformation from a cuboctahedral structure to an icosahedral-like structure before melting. Our dynamical results showed that doping of the Ir55 cluster with an Au atom sharply increases the self-diffusion coefficient in the initial state in the solid phase, especially in icosahedral and cuboctahedral structures. It is also shown that the Ir13Au42 cluster in icosahedral and cuboctahedral and the Ir7Au47 and Ir17Au37 clusters in decahedral morphologies have smaller values of self-diffusion coefficients than other clusters after the melting point and that this could be due to the formation of core-shell structures.
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Affiliation(s)
- Hamed Akbarzadeh
- Department of Chemistry, Faculty of Basic Sciences, Hakim Sabzevari University, 96179-76487 Sabzevar, Iran.
| | - Mohsen Abbaspour
- Department of Chemistry, Faculty of Basic Sciences, Hakim Sabzevari University, 96179-76487 Sabzevar, Iran.
| | - Esmat Mehrjouei
- Department of Chemistry, Faculty of Basic Sciences, Hakim Sabzevari University, 96179-76487 Sabzevar, Iran.
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10
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Chiriki S, Jindal S, Bulusu SS. c-T phase diagram and Landau free energies of (AgAu)55 nanoalloy via neural-network molecular dynamic simulations. J Chem Phys 2017; 147:154303. [DOI: 10.1063/1.4998319] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Siva Chiriki
- Discipline of Chemistry, Indian Institute of Technology (IIT) Indore, Indore, Madhya Pradesh 453552, India
| | - Shweta Jindal
- Discipline of Chemistry, Indian Institute of Technology (IIT) Indore, Indore, Madhya Pradesh 453552, India
| | - Satya S. Bulusu
- Discipline of Chemistry, Indian Institute of Technology (IIT) Indore, Indore, Madhya Pradesh 453552, India
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11
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Akbarzadeh H, Abbaspour M, Mehrjouei E. Au@Pt and Pt@Au nanoalloys in the icosahedral and cuboctahedral structures: Which is more stable? J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.07.096] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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12
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Akbarzadeh H, Abbaspour M. Investigation of melting and freezing of Ag–Au alloy nanoclusters supported on carbon nanotube using molecular dynamics simulations. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.02.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Zhao Z, Fisher A, Cheng D. Phase diagram and segregation of Ag-Co nanoalloys: insights from theory and simulation. NANOTECHNOLOGY 2016; 27:115702. [PMID: 26876185 DOI: 10.1088/0957-4484/27/11/115702] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Understanding the phase diagram is the first step to identifying the structure-performance relationship of a material at the nanoscale. In this work, a modified nanothermodynamical model has been developed to predict the phase diagrams of Ag-Co nanoalloys with the size of 1 ∼ 100 nm, which also overcomes the difference in the predicted results between theory and simulation for the first time. Based on this modified model, the phase diagrams of Ag-Co nanoalloys with various polyhedral morphologies (tetrahedron, cube, octahedron, decahedron, dodecahedron, rhombic dodecahedron, truncated octahedron, cuboctahedron, and icosahedron) have been predicted, showing good agreement with molecular dynamics simulations at the nanoscale of 1 ∼ 4 nm. In addition, the surface segregation of Ag-Co nanoalloys has been predicted with a Co-rich core/Ag-rich surface, which is also consistent with the simulation results. Our results highlight a useful roadmap for bridging the difference between theory and simulation in the prediction of the phase diagram at the nanoscale, which will help both theorists and experimentalists.
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Affiliation(s)
- Zheng Zhao
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
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14
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Akbarzadeh H, Abbaspour M, Salemi S. Carbon monoxide adsorption on the single-walled carbon nanotube supported gold–silver nanoalloys. NEW J CHEM 2016. [DOI: 10.1039/c5nj01382h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The carbon nanotube diameter and chirality have significant influences on CO adsorption.
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Affiliation(s)
- Hamed Akbarzadeh
- Department of Chemistry
- Faculty of Basic Sciences
- Hakim Sabzevari University
- 96179-76487 Sabzevar
- Iran
| | - Mohsen Abbaspour
- Department of Chemistry
- Faculty of Basic Sciences
- Hakim Sabzevari University
- 96179-76487 Sabzevar
- Iran
| | - Sirous Salemi
- Department of Chemistry
- Faculty of Basic Sciences
- Hakim Sabzevari University
- 96179-76487 Sabzevar
- Iran
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15
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Akbarzadeh H, Abbaspour M, Mehrjouei E. Investigation of thermal, structural and dynamical properties of (Aux–Cuy–Niy)N=32,108,256 ternary nanosystems: effect of Au addition to Cu–Ni bimetallic nanoclusters via MD simulation. RSC Adv 2016. [DOI: 10.1039/c6ra13057g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this work, we have investigated the heating and cooling processes for ternary metallic nanoclusters with different Au mole fractions using molecular dynamics simulation.
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Affiliation(s)
- Hamed Akbarzadeh
- Department of Chemistry
- Faculty of Basic Sciences
- Hakim Sabzevari University
- 96179-76487 Sabzevar
- Iran
| | - Mohsen Abbaspour
- Department of Chemistry
- Faculty of Basic Sciences
- Hakim Sabzevari University
- 96179-76487 Sabzevar
- Iran
| | - Esmat Mehrjouei
- Department of Chemistry
- Faculty of Basic Sciences
- Hakim Sabzevari University
- 96179-76487 Sabzevar
- Iran
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Abstract
This article presents a perspective on thermodynamic characterization of metal nanoparticles by computational chemistry. Topics emphasized include structural stability, phases, phase changes, and free energy functions of aluminum nanoparticles.
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Affiliation(s)
- Zhen Hua Li
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials
- Fudan University
- Shanghai 200433, China
| | - Donald G. Truhlar
- Department of Chemistry
- Chemical Theory Center, and Supercomputing Institute
- University of Minnesota
- Minneapolis, USA
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17
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Shin K, Kim DH, Lee HM. Catalytic characteristics of AgCu bimetallic nanoparticles in the oxygen reduction reaction. CHEMSUSCHEM 2013; 6:1044-1049. [PMID: 23650210 DOI: 10.1002/cssc.201201001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 02/28/2013] [Indexed: 06/02/2023]
Abstract
Intensive research on oxygen reduction reaction (ORR) catalysts has been undertaken to find a Pt substitute or reduce the amount of Pt. Ag nanoparticles are potential Pt substitutes; however, the weak oxygen adsorption energy of Ag prompted investigation of other catalysts. Herein, we prepared AgCu bimetallic nanoparticle (NP) systems to improve the catalytic performance and compared the catalytic performance of Ag, Cu, AgCu (core-shell), and AgCu (alloy) NP systems as new catalyst by investigating the adsorption energy of oxygen and the activation energy of oxygen dissociation, which is known to be the rate-determining step of ORR. By analyzing HOMO-level isosurfaces of metal NPs and oxygen, we found that the adsorption sites and the oxygen adsorption energies varied with different configurations of NPs. We then plotted the oxygen adsorption energies against the energy barrier of oxygen dissociation to determine the catalytic performance. AgCu (alloy) and Cu NPs exhibited strong adsorption energies and low activation-energy barriers. However, the overly strong oxygen adsorption energy of Cu NPs hindered the ORR.
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Affiliation(s)
- Kihyun Shin
- Department of Materials Science & Engineering, Korea Advanced Institute of Science & Technology (KAIST), 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea
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Ouyang G, Yang G, Zhou G. A comprehensive understanding of melting temperature of nanowire, nanotube and bulk counterpart. NANOSCALE 2012; 4:2748-2753. [PMID: 22422101 DOI: 10.1039/c2nr30095h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Surface energies of nanostructures are of considerable interest, and thermodynamic methods have provided valuable insight into the physics and chemistry of these systems. Although the effect of surface energy on melting behaviors of nanostructures has been widely investigated in theoretical calculations and simulations, from the thermodynamics at the nanometer scale point of view, the comprehensive understanding of the fundamental physical and chemical issues involved in nanostructures' melting is still lacking. For instance, nanostructures with negative curvature, such as nanotubes, show different melting behaviors compared with the nanostructures with positive curvature such as nanowires, and both nanotubes and nanowires exhibit abnormal melting temperature compared with that of the bulk counterparts. Herein, we put forward a general model to elucidate the melting temperature of the nanostructures with positive and negative curvatures based on the surface energy at the nanometer. Further, the surface mean square relative atomic displacement (MSRD) of these nanostructures has been studied from the perspective of the size-dependent cohesive energy consideration, which can provide the atomic understanding of the nanostructures' melting. Theoretical analyses indicate that both melting temperatures of the nanostructures with the positive and negative curvatures decrease with decreasing dimensionality, and the surface MSRDs show different size effects in the systems with the positive and negative curvatures, respectively. The melting temperature of the surface with the negative curvature is higher than that of the surface with the positive curvature, and both melting temperatures are smaller than that of the bulk counterpart when the size of nanostructures is less than a threshold value. The unique melting behaviors of nanostructures are attributed to the size- and curvature-dependent surface energy of nanostructures. These results provide new insight into the fundamental understanding of the melting temperature of nanostructures.
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Affiliation(s)
- Gang Ouyang
- Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Department of Physics, Hunan Normal University, Changsha 410081, Hunan, P. R. China.
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