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Watanabe J, Tanaka Y, Maeda Y, Harada Y, Hirokawa Y, Kawakita H, Ohto K, Morisada S. Surfactant-Assisted Synthesis of Pt Nanocubes Using Poly( N-isopropylacrylamide) Nanogels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:11859-11868. [PMID: 34583506 DOI: 10.1021/acs.langmuir.1c01873] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Poly(N-isopropylacrylamide) (PNIPAM) nanogels were prepared by emulsion polymerization using sodium dodecyl sulfate (SDS) and employed as a capping agent in platinum nanoparticle (Pt NP) synthesis by liquid-phase reduction with hydrogen gas. When the PNIPAM nanogels were used without removing SDS, that is, a slight amount of SDS was included in the reaction solution, Pt nanocubes (NCs) were predominantly produced (>80%). The proportion of the resultant Pt NCs was much higher than that obtained using the PNIPAM linear polymer (∼60%). To clarify the effects of the three-dimensional polymer network and SDS, we synthesized Pt NPs using the PNIPAM nanogel without SDS (SDS-free PNIPAM nanogel) and found that Pt NCs are rarely formed, and most NPs obtained have an irregular shape. When only SDS was used as a capping agent, NCs were hardly obtained, but other polyhedral NPs were formed. Furthermore, the use of SDS together with the PNIPAM polymer led to the decrease in the proportion of the Pt NCs compared with that obtained using only the linear polymer. These results indicate that the enhancement of the Pt NC proportion using the PNIPAM nanogel with SDS is attributable to not only the three-dimensional polymer network of the PNIPAM nanogel but also the assist of SDS as a capping agent.
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Affiliation(s)
- Jun Watanabe
- Department of Environmental Chemistry and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa 226-8502, Japan
| | - Yoshiaki Tanaka
- Department of Environmental Chemistry and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa 226-8502, Japan
| | - Yuusuke Maeda
- Department of Chemistry and Applied Chemistry, Saga University, 1 Honjo, Saga 840-8502, Japan
| | - Yusuke Harada
- Department of Chemistry and Applied Chemistry, Saga University, 1 Honjo, Saga 840-8502, Japan
| | - Yoshitsugu Hirokawa
- Department of Materials Science, The University of Shiga Prefecture, 2500 Hassaka, Hikone, Shiga 522-8533, Japan
| | - Hidetaka Kawakita
- Department of Chemistry and Applied Chemistry, Saga University, 1 Honjo, Saga 840-8502, Japan
| | - Keisuke Ohto
- Department of Chemistry and Applied Chemistry, Saga University, 1 Honjo, Saga 840-8502, Japan
| | - Shintaro Morisada
- Department of Chemistry and Applied Chemistry, Saga University, 1 Honjo, Saga 840-8502, Japan
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2
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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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3
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Synthesis and applications of anisotropic nanoparticles with precisely defined dimensions. Nat Rev Chem 2020; 5:21-45. [PMID: 37118104 DOI: 10.1038/s41570-020-00232-7] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2020] [Indexed: 02/07/2023]
Abstract
Shape and size play powerful roles in determining the properties of a material; controlling these aspects with precision is therefore an important, fundamental goal of the chemical sciences. In particular, the introduction of shape anisotropy at the nanoscale has emerged as a potent way to access new properties and functionality, enabling the exploration of complex nanomaterials across a range of applications. Recent advances in DNA and protein nanotechnology, inorganic crystallization techniques, and precision polymer self-assembly are now enabling unprecedented control over the synthesis of anisotropic nanoparticles with a variety of shapes, encompassing one-dimensional rods, dumbbells and wires, two-dimensional and three-dimensional platelets, rings, polyhedra, stars, and more. This has, in turn, enabled much progress to be made in our understanding of how anisotropy and particle dimensions can be tuned to produce materials with unique and optimized properties. In this Review, we bring these recent developments together to critically appraise the different methods for the bottom-up synthesis of anisotropic nanoparticles enabling exquisite control over morphology and dimensions. We highlight the unique properties of these materials in arenas as diverse as electron transport and biological processing, illustrating how they can be leveraged to produce devices and materials with otherwise inaccessible functionality. By making size and shape our focus, we aim to identify potential synergies between different disciplines and produce a road map for future research in this crucial area.
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4
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Leteba GM, Mitchell DRG, Levecque PBJ, van Steen E, Lang CI. Topographical and compositional engineering of core-shell Ni@Pt ORR electro-catalysts. RSC Adv 2020; 10:29268-29277. [PMID: 35521089 PMCID: PMC9055937 DOI: 10.1039/d0ra05195k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 07/31/2020] [Indexed: 12/19/2022] Open
Abstract
Complex faceted geometries and compositional anisotropy in alloy nanoparticles (NPs) can enhance catalytic performance. We report on the preparation of binary PtNi NPs via a co-thermolytic approach in which we optimize the synthesis variables, which results in significantly improved catalytic performance. We used scanning transmission electron microscopy to characterise the range of morphologies produced, which included spherical and concave cuboidal core–shell structures. Electrocatalytic activity was evaluated using a rotating disc electrode (1600 rpm) in 0.1 M HClO4; the electrocatalytic performance of these Ni@Pt NPs showed significant (∼11-fold) improvement compared to a commercial Pt/C catalyst. Extended cycling revealed that electrochemical surface area was retained by cuboidal PtNi NPs post 5000 electrochemical cycles (0.05–1.00 V, vs. SHE). This is attributed to the enclosure of Ni atoms by a thick Pt shell, thus limiting Ni dissolution from the alloy structures. The novel synthetic strategy presented here results in a high yield of Ni@Pt NPs which show excellent electro-catalytic activity and useful durability. Complex faceted geometries and compositional anisotropy in alloy nanoparticles (NPs) can enhance catalytic performance.![]()
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Affiliation(s)
- Gerard M Leteba
- Catalysis Institute, Department of Chemical Engineering, University of Cape Town Cape Town 7700 South Africa .,School of Engineering, Macquarie University Sydney NSW 2109 Australia
| | - David R G Mitchell
- Electron Microscopy Centre, Innovation Campus, University of Wollongong Wollongong NSW 2517 Australia
| | - Pieter B J Levecque
- Catalysis Institute, Department of Chemical Engineering, University of Cape Town Cape Town 7700 South Africa
| | - Eric van Steen
- Catalysis Institute, Department of Chemical Engineering, University of Cape Town Cape Town 7700 South Africa
| | - Candace I Lang
- School of Engineering, Macquarie University Sydney NSW 2109 Australia
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5
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Kaiser M, Martinez Y, Schmidt AM, Sánchez PA, Kantorovich SS. Diffusion of single active-dipolar cubes in applied fields. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112688] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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6
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Li Y, Yun KH, Lee H, Goh SH, Suh YG, Choi Y. Porous platinum nanoparticles as a high-Z and oxygen generating nanozyme for enhanced radiotherapy in vivo. Biomaterials 2019; 197:12-19. [DOI: 10.1016/j.biomaterials.2019.01.004] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/03/2019] [Accepted: 01/03/2019] [Indexed: 10/27/2022]
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Leteba GM, Mitchell DRG, Levecque PBJ, Lang CI. Solution-Grown Dendritic Pt-Based Ternary Nanostructures for Enhanced Oxygen Reduction Reaction Functionality. NANOMATERIALS 2018; 8:nano8070462. [PMID: 29949875 PMCID: PMC6070889 DOI: 10.3390/nano8070462] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/16/2018] [Accepted: 06/22/2018] [Indexed: 11/16/2022]
Abstract
Nanoalloys with anisotropic morphologies of branched and porous internal structures show great promise in many applications as high performance materials. Reported synthetic approaches for branched alloy nanostructures are, however, limited by the synthesis using a seed-growth process. Here, we demonstrate a conveniently fast and one-pot solution-phase thermal reduction strategy yielding nanoalloys of Pt with various solute feed ratios, exhibiting hyperbranched morphologies and good dispersity. When Pt was alloyed with transition metals (Ni, Co, Fe), we observed well-defined dendritic nanostructures in PtNi, PtCo and Pt(NiCo), but not in PtFe, Pt(FeNi) or Pt(FeCo) due to the steric hindrance of the trivalent Fe(acac)₃ precursor used during synthesis. In the case of Pt-based nanoalloys containing Ni and Co, the dendritic morphological evolution observed was insensitive to large variations in solute concentration. The functionality of these nanoalloys towards the oxygen reduction reaction (ORR); however, was observed to be dependent on the composition, increasing with increasing solute content. Pt₃(NiCo)₂ exhibited superior catalytic activity, affording about a five- and 10-fold enhancement in area-specific and mass-specific catalytic activities, respectively, compared to the standard Pt/C nanocatalyst. This solution-based synthetic route offers a new approach for constructing dendritic Pt-based nanostructures with excellent product yield, monodispersity and high crystallinity.
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Affiliation(s)
- Gerard M Leteba
- Department of Chemical Engineering, Catalysis Institute, University of Cape Town, Cape Town 7700, South Africa.
- School of Engineering, Macquarie University, Sydney NSW 2109, Australia.
| | - David R G Mitchell
- Electron Microscopy Centre, University of Wollongong, Wollongong NSW 2522, Australia.
| | - Pieter B J Levecque
- Department of Chemical Engineering, Catalysis Institute, University of Cape Town, Cape Town 7700, South Africa.
| | - Candace I Lang
- School of Engineering, Macquarie University, Sydney NSW 2109, Australia.
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8
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Ly N, Al-Shamery K, Chan-Thaw CE, Prati L, Carniti P, Gervasini A. Impact of Support Oxide Acidity in Pt-Catalyzed HMF Hydrogenation in Alcoholic Medium. Catal Letters 2016. [DOI: 10.1007/s10562-016-1945-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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9
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Di Paola C, D'Agosta R, Baletto F. Geometrical Effects on the Magnetic Properties of Nanoparticles. NANO LETTERS 2016; 16:2885-2889. [PMID: 27007172 DOI: 10.1021/acs.nanolett.6b00916] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Elucidating the connection between shape and properties is a challenging but essential task for a rational design of nanoparticles at the atomic level. As a paradigmatic example we investigate how geometry can influence the magnetic properties of nanoparticles, focusing in particular on platinum clusters of 1-2 nm in size. Through first-principle calculations, we have found that the total magnetization depends strongly on the local atomic arrangements. This is due to a contraction of the nearest neighbor distance together with an elongation of the second nearest neighbor distance, resulting in an interatomic partial charge transfer from the atoms lying on the subsurface layer (donors) toward the vertexes (acceptors).
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Affiliation(s)
- Cono Di Paola
- Department of Physics, King's College London , WC2R 2LS, London, United Kingdom
- Department of Earth Sciences, University College London , WC1E 6BT, London, United Kingdom
| | - Roberto D'Agosta
- Department of Physics, King's College London , WC2R 2LS, London, United Kingdom
- Nano-bio Spectroscopy Group and ETSF, Universidad del País Vasco , CFM CSIC-UPV/EHU, E-20018 San Sebastián, Spain
- Ikerbasque, Basque Foundation for Science, E-48013, Bilbao, Spain
| | - Francesca Baletto
- Department of Physics, King's College London , WC2R 2LS, London, United Kingdom
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10
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Hwang ET, Lee YW, Park HC, Kwak DH, Kim DM, Kim SJ, Kim MC, Lee JY, Lee S, Park KW. Synthesis of Pt-Rich@Pt–Ni alloy core–shell nanoparticles using halides. RSC Adv 2015. [DOI: 10.1039/c4ra14095h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We demonstrated the synthesis of Pt–Ni alloy core–shell nanoparticles (NPs) via a one-pot thermal decomposition method, optimized by variation of the concentration of cetyltrimethylammonium chloride (CTAC) and reaction time.
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Affiliation(s)
- Eui-Tak Hwang
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Young-Woo Lee
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Han-Chul Park
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Da-Hee Kwak
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Da-Mi Kim
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Si-Jin Kim
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Min-Cheol Kim
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Jin-Yeon Lee
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Seul Lee
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
| | - Kyung-Won Park
- Department of Chemical Engineering
- Soongsil University
- Seoul 156743
- Republic of Korea
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11
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Barron H, Barnard AS. Using structural diversity to tune the catalytic performance of Pt nanoparticle ensembles. Catal Sci Technol 2015. [DOI: 10.1039/c5cy00123d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
While reducing the size, and restricting shape of nanocatalysts can improve performance, monodispersed samples are not necessarily ideal.
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Affiliation(s)
- Hector Barron
- CSIRO Virtual Nanoscience Laboratory
- Parkville
- Australia
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12
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Ma Y, Xu L, Chen W, Zou C, Yang Y, Zhang L, Huang S. Evolution from small sized Au nanoparticles to hollow Pt/Au nanostructures with Pt nanorods and a mechanistic study. RSC Adv 2015. [DOI: 10.1039/c5ra21807a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
A facile method for synthesizing hollow Au/Pt nanostructures is reported; this strategy involves using small sized Au nanoparticles (NPs) as seeds and KI as growth modifier.
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Affiliation(s)
- Ying Ma
- Nanomaterials and Chemistry Key Laboratory
- Wenzhou University
- Wenzhou
- P. R. China
| | - Li Xu
- Nanomaterials and Chemistry Key Laboratory
- Wenzhou University
- Wenzhou
- P. R. China
| | - Wei Chen
- Nanomaterials and Chemistry Key Laboratory
- Wenzhou University
- Wenzhou
- P. R. China
| | - Chao Zou
- Nanomaterials and Chemistry Key Laboratory
- Wenzhou University
- Wenzhou
- P. R. China
| | - Yun Yang
- Nanomaterials and Chemistry Key Laboratory
- Wenzhou University
- Wenzhou
- P. R. China
| | - Lijie Zhang
- Nanomaterials and Chemistry Key Laboratory
- Wenzhou University
- Wenzhou
- P. R. China
| | - Shaoming Huang
- Nanomaterials and Chemistry Key Laboratory
- Wenzhou University
- Wenzhou
- P. R. China
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13
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Osmić M, Kolny-Olesiak J, Al-Shamery K. Size control and shape evolution of single-twinned platinum nanocrystals in a room temperature colloidal synthesis. CrystEngComm 2014. [DOI: 10.1039/c4ce01342e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Yang S, Luo X. Mesoporous nano/micro noble metal particles: synthesis and applications. NANOSCALE 2014; 6:4438-57. [PMID: 24676151 DOI: 10.1039/c3nr06858g] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The morphology, size and composition often govern the physical and chemical properties of noble metal units with a size in the nano or micro scale. Thus, the controlled growth of noble metal crystals would help to tailor their unique properties and this would be followed by their practical application. Mesoporous nano/micro noble metal units are types of nanostructured material that have fascinating properties that can generate great potential for various applications. This review presents a general view on the growth mechanisms of porous noble metal units and is focused on recent progresses in their synthetic approaches. Then, their potential applications in the field of drug delivery, cell imaging and SERS substrates, as well as fuel cell catalysts are overviewed.
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Affiliation(s)
- Shengchun Yang
- MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, State Key Laboratory for Mechanical Behavior of Materials, School of Science, Xi'an Jiaotong University, Shann Xi, 710049, People's Republic of China.
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15
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Crespo P, de la Presa P, Marín P, Multigner M, Alonso JM, Rivero G, Yndurain F, González-Calbet JM, Hernando A. Magnetism in nanoparticles: tuning properties with coatings. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:484006. [PMID: 24201075 DOI: 10.1088/0953-8984/25/48/484006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This paper reviews the effect of organic and inorganic coatings on magnetic nanoparticles. The ferromagnetic-like behaviour observed in nanoparticles constituted by materials which are non-magnetic in bulk is analysed for two cases: (a) Pd and Pt nanoparticles, formed by substances close to the onset of ferromagnetism, and (b) Au and ZnO nanoparticles, which were found to be surprisingly magnetic at the nanoscale when coated by organic surfactants. An overview of theories accounting for this unexpected magnetism, induced by the nanosize influence, is presented. In addition, the effect of coating magnetic nanoparticles with biocompatible metals, oxides or organic molecules is also reviewed, focusing on their applications.
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16
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Mourdikoudis S, Collière V, Amiens C, Fau P, Kahn ML. Metal-organic pathways for anisotropic growth of a highly symmetrical crystal structure: example of the fcc Ni. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:13491-13501. [PMID: 23927494 DOI: 10.1021/la402001t] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The control of the metallic nanocrystal shape is of prime importance for a wide variety of applications. We report a detailed research work on metal-organic chemical routes for the synthesis of a highly symmetrical crystal structure. In particular, this study shows the key parameters ensuring the anisotropic growth of nickel nanostructures (fcc crystal). Numerous reaction conditions are investigated (precursors, solvents, temperature, reducing agents, reaction time, and types and ratios of surfactants, such as alkyl amines, carboxylic acids, and phosphine oxides), and their effects on the size and shape of the final product are reported. The role of the growth modifiers and the structuring of the reaction media on the anisotropic growth are demonstrated. This metal-organic approach generates several novel anisotropic nanostructures in a wide size range depending on the reaction conditions. In this way, nanomaterials with reproducible size, shape, and composition are obtained with good yield. Transmission electron microscopy techniques (TEM and HRTEM) are the principal methods for monitoring the morphology.
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Affiliation(s)
- Stefanos Mourdikoudis
- Laboratoire de Chimie de Coordination, CNRS UPR8241, 205 , route de Narbonne, 31077 Toulouse, France
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17
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Two-dimensional self-assembly of hydrophobic nanoparticles at oil/water interfaces via nanoscale phase separation of mixed ligands. J Colloid Interface Sci 2013; 407:243-9. [DOI: 10.1016/j.jcis.2013.06.071] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Revised: 06/24/2013] [Accepted: 06/25/2013] [Indexed: 12/13/2022]
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18
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Wang Y, Tang A, Li K, Yang C, Wang M, Ye H, Hou Y, Teng F. Shape-controlled synthesis of PbS nanocrystals via a simple one-step process. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:16436-16443. [PMID: 23126602 DOI: 10.1021/la303738u] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A one-step colloidal process was adopted to prepare face-centered-cubic PbS nanocrystals with different shapes such as octahedral, starlike, cubic, truncated octahedral, and truncated cubic. The features of this approach avoid the presynthesis of any organometallic precursor and the injection of a toxic phosphine agent. A layered intermediate compound (lead thiolate) forms in the initial stage of the reaction, which effectively acts as the precursor to decompose into the PbS nanocrystals. The size and shape of the PbS nanocrystals can be easily controlled by varying the reaction time, the reactant concentrations, the reaction temperatures, and the amount of surfactants. In particular, additional surfactants other than dodecanethiol, such as oleylamine, oleic acid, and octadecene, play an important role in the shape control of the products. The possible formation mechanism for the PbS nanocrystals with various shapes is presented on the basis of the different growth directions of the nanocrystals with the assistance of the different surfactants. This method provides a facile, low-cost, highly reproducible process for the synthesis of PbS nanocrystals that may have potential applications in the fabrication of photovoltaic devices and photodetectors.
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Affiliation(s)
- Yu Wang
- Department of Chemistry, Ministry of Education, School of Science, Beijing JiaoTong University, Beijing 100044, PR China
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19
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LI SIYUE, WANG MIN. BRANCHED METAL NANOPARTICLES: A REVIEW ON WET-CHEMICAL SYNTHESIS AND BIOMEDICAL APPLICATIONS. ACTA ACUST UNITED AC 2012. [DOI: 10.1142/s1793984411000311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Branched metal nanoparticles present a promising new class of materials, which have great potential as sensors, catalysts, drug carriers, and imaging agents, owing to their unique nanostructures, physicochemical properties, optical properties, and other characteristics. Many efforts have recently been devoted to the wet-chemical synthesis of branched metal nanoparticles. Seed-mediated growth and seedless growth are two main routes for producing branched metal nanoparticles. Most particle synthesis methods can be modified for different metal systems. In this review, various synthesis methods for the fabrication of branched monometallic, bimetallic, and multimetallic nanoparticles and also branched polymer core-metal nanoshell composite nanoparticles are summarized, catagorized, and discussed. The relevance and performance of such nanostructured materials with regard to their optical properties which arise from localized surface plasmon resonances are summarized, and their potential as excellent substrates for surface enhanced Raman scattering (SERS) is reviewed. Other applications of branched nanoparticles such as drug delivery vehicle, medical imaging agent, catalysis, and magnetism are briefly introduced.
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Affiliation(s)
- SI YUE LI
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - MIN WANG
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong
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20
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Lacroix LM, Gatel C, Arenal R, Garcia C, Lachaize S, Blon T, Warot-Fonrose B, Snoeck E, Chaudret B, Viau G. Tuning Complex Shapes in Platinum Nanoparticles: From Cubic Dendrites to Fivefold Stars. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201107425] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Lacroix LM, Gatel C, Arenal R, Garcia C, Lachaize S, Blon T, Warot-Fonrose B, Snoeck E, Chaudret B, Viau G. Tuning complex shapes in platinum nanoparticles: from cubic dendrites to fivefold stars. Angew Chem Int Ed Engl 2012; 51:4690-4. [PMID: 22474000 DOI: 10.1002/anie.201107425] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 03/07/2012] [Indexed: 11/08/2022]
Affiliation(s)
- Lise-Marie Lacroix
- LPCNO, Université de Toulouse, INSA, UPS, CNRS, 135 avenue de Rangueil, 31077 Toulouse, France.
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Tong G, Hu Q, Wu W, Li W, Qian H, Liang Y. Submicrometer-sized NiO octahedra: facile one-pot solid synthesis, formation mechanism, and chemical conversion into Ni octahedra with excellent microwave-absorbing properties. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm31790g] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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MA DONGLING, KELL ARNOLD. HOLLOW, BRANCHED AND MULTIFUNCTIONAL NANOPARTICLES: SYNTHESIS, PROPERTIES AND APPLICATIONS. INTERNATIONAL JOURNAL OF NANOSCIENCE 2011. [DOI: 10.1142/s0219581x09006419] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Nanoscale materials with various structures have attracted extensive research interest during the past decade. Among them, hollow, branched and multifunctional nanoparticles comprised of two different nanoparticle components are emerging as new classes of interesting nanomaterials owing to the unique optical, catalytic, electrical, magnetic and mechanical properties associated with their unusual morphologies as well as their potential wide range of applications in various fields such as photothermal therapy, diagnosis, drug delivery, catalysis, optoelectronic, electronics and biodiagnostics. In particular, branched nanoparticles promise to serve as building blocks for more complex materials and advanced devices through self-assembly and self-alignment and heterodimeric nanoparticles show promise for the development of tunable magnetic materials and multimodal biodiagnostic imaging tools.
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Affiliation(s)
- DONGLING MA
- Institut national de la recherche scientifique, University of Quebec, Varennes, Quebec, J3X 1S2, Canada
| | - ARNOLD KELL
- Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada
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24
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Buonsanti R, Carlino E, Giannini C, Altamura D, De Marco L, Giannuzzi R, Manca M, Gigli G, Cozzoli PD. Hyperbranched Anatase TiO2 Nanocrystals: Nonaqueous Synthesis, Growth Mechanism, and Exploitation in Dye-Sensitized Solar Cells. J Am Chem Soc 2011; 133:19216-39. [DOI: 10.1021/ja208418z] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Raffaella Buonsanti
- National Nanotechnology Laboratory (NNL), Istituto Nanoscienze CNR, c/o Distretto Tecnologico, via per Arnesano km 5, 73100 Lecce, Italy
| | - Elvio Carlino
- TASC National Laboratory, IOM-CNR, Area Science Park - Basovizza, Building MM, SS 14, Km 163.5, 34149 Trieste, Italy
| | - Cinzia Giannini
- Istituto di Crystallografia (IC−CNR), via Amendola 122/O, I-70126 bari, Italy
| | - Davide Altamura
- Istituto di Crystallografia (IC−CNR), via Amendola 122/O, I-70126 bari, Italy
| | - Luisa De Marco
- Center for Biomolecular Nanotechnologies - Italian Institute of Technology (IIT), c/o Stamms, via Barsanti, 73010 Arnesano (Lecce), Italy
| | - Roberto Giannuzzi
- Center for Biomolecular Nanotechnologies - Italian Institute of Technology (IIT), c/o Stamms, via Barsanti, 73010 Arnesano (Lecce), Italy
| | - Michele Manca
- Center for Biomolecular Nanotechnologies - Italian Institute of Technology (IIT), c/o Stamms, via Barsanti, 73010 Arnesano (Lecce), Italy
| | - Giuseppe Gigli
- National Nanotechnology Laboratory (NNL), Istituto Nanoscienze CNR, c/o Distretto Tecnologico, via per Arnesano km 5, 73100 Lecce, Italy
- Dipartimento di Ingegneria dell’Innovazione, Università del Salento, via per Arnesano, 73100 Lecce, Italy
| | - P. Davide Cozzoli
- National Nanotechnology Laboratory (NNL), Istituto Nanoscienze CNR, c/o Distretto Tecnologico, via per Arnesano km 5, 73100 Lecce, Italy
- Dipartimento di Ingegneria dell’Innovazione, Università del Salento, via per Arnesano, 73100 Lecce, Italy
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25
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Sonström P, Bäumer M. Supported colloidal nanoparticles in heterogeneous gas phase catalysis: on the way to tailored catalysts. Phys Chem Chem Phys 2011; 13:19270-84. [PMID: 21960322 DOI: 10.1039/c1cp22048a] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using colloidally synthesized nanoparticles for the preparation of supported catalysts offers several advantages (e.g. precise control of particle size and morphology) when compared to traditional preparation techniques. Although such nanoparticles have already been very successfully used for catalytic applications in the liquid phase, applications in heterogeneous gas phase catalysis are still scarce. One aspect, usually considered as a problem, is organic stabilizers typically employed during the nanoparticle synthesis since they or their decomposition products are supposed to block catalytically active sites on the nanoparticle surface. Thus, in many studies so far, the removal of the organic ligands prior to use in gas phase catalysis has been proposed. In this perspective article, however, we will discuss a number of benefits such ligand shells may have for heterogeneous gas phase catalysis, including the protection against chemical modification, prevention of sintering and tuning of SMSI effects.
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Affiliation(s)
- P Sonström
- Institute of Applied and Physical Chemistry, University of Bremen, Leobener Str. NW 2, 28359 Bremen, Germany
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26
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Kowlgi KNK, Koper GJM, Picken SJ, Lafont U, Zhang L, Norder B. Synthesis of magnetic noble metal (nano)particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:7783-7787. [PMID: 21598929 DOI: 10.1021/la105051v] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Noble metal particles can be made strongly ferromagnetic or diamagnetic provided that they are synthesized in a sufficiently strong magnetic field. Here we outline two synthesis methods that are fast, reproducible, and allow broad control over particle sizes ranging from nanometers to millimeters. From magnetometry and light spectroscopy, it appears that the cause of this anomalous magnetism is the surface anisotropy in the noble metal particles induced by the applied magnetic field. This work offers an elegant alternative to composite materials of noble metals and magnetic impurities.
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Affiliation(s)
- Krishna N K Kowlgi
- Self-Assembling Systems, Department of Chemical Engineering, Delft University of Technology, Julianalaan 136 , 2628 BL Delft, The Netherlands
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27
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Guerrero-Martínez A, Barbosa S, Pastoriza-Santos I, Liz-Marzán LM. Nanostars shine bright for you. Curr Opin Colloid Interface Sci 2011. [DOI: 10.1016/j.cocis.2010.12.007] [Citation(s) in RCA: 318] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Gong X, Yang Y, Huang S. Mn3O4catalyzed growth of polycrystalline Pt nanoparticles and single crystalline Pt nanorods with high index facets. Chem Commun (Camb) 2011; 47:1009-11. [DOI: 10.1039/c0cc03656k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Gong X, Yang Y, Zhang L, Zou C, Cai P, Chen G, Huang S. Controlled synthesis of Pt nanoparticles via seeding growth and their shape-dependent catalytic activity. J Colloid Interface Sci 2010; 352:379-85. [DOI: 10.1016/j.jcis.2010.08.069] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 08/25/2010] [Accepted: 08/26/2010] [Indexed: 11/29/2022]
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30
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31
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Cheong S, Watt JD, Tilley RD. Shape control of platinum and palladium nanoparticles for catalysis. NANOSCALE 2010; 2:2045-53. [PMID: 20694209 DOI: 10.1039/c0nr00276c] [Citation(s) in RCA: 191] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Platinum and palladium are important catalysts for a wide variety of industrial processes. With the increasing demands of these materials, the development of high-performance catalysts is an important area of research, and as a result, shape control synthesis has become one of the leading research focuses. This minireview surveys the different approaches in solution-phase synthesis that have been successfully adopted for achieving shaped platinum and palladium nanoparticles that are enclosed with specific crystallographic facets. In addition, catalytic studies of the shaped nanoparticles are highlighted, in which promising results have been reported in terms of enhanced activity and selectivity. The future outlook discusses the aspects in synthesis and catalysis to be considered for the development of highly efficient and effective catalysts.
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Affiliation(s)
- Soshan Cheong
- School of Chemical and Physical Sciences and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington 6012, New Zealand
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32
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Yuan J, Choo ESG, Tang X, Sheng Y, Ding J, Xue J. Synthesis of ZnO-Pt nanoflowers and their photocatalytic applications. NANOTECHNOLOGY 2010; 21:185606. [PMID: 20388976 DOI: 10.1088/0957-4484/21/18/185606] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The photocatalytic behaviors of ZnO nanoparticles have been intensively studied recently. However, the photocatalytic efficiency of pure ZnO nanoparticles always suffers from the quick recombination of photoexcited electrons and holes. In order to suppress the electron-hole recombination and then raise the photocatalytic efficiency of ZnO, metal nanoparticles have been combined with ZnO to form ZnO-metal heterostructures. In this work, the feasibility of synthesizing ZnO-Pt composite nanoflowers for optimized catalytic properties was studied. Three different Pt nanocrystals, i.e. cubic Pt nanocrystals enclosed by {100} facets, octahedral Pt nanocrystals enclosed by {111} facets, and truncated octahedral Pt nanocrystals enclosed by both {111} and {100} facets, were selected as seeds for epitaxial growth of ZnO. A ZnO-Pt flowerlike nanostructure was formed by selective growth of ZnO nanolobes at {111} facets of the truncated octahedral Pt nanocrystals. The resultant nanoflowers had well defined ZnO-Pt interfaces and exposed Pt {100} facets, as confirmed by transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) measurements. The photocatalytic behaviors of the resultant ZnO-Pt nanoflowers were demonstrated in the photodegradation of ethyl violet. In comparison with the commercial TiO(2) photocatalyst P25, the ZnO-Pt flowerlike nanostructures showed improved catalytic efficiency. Notable ferromagnetism of the obtained ZnO-Pt flowerlike nanostructures was also observed. It is believed that the ZnO-Pt interface played an important role in the enlarged magnetic coercivity of the ZnO-Pt nanoflowers.
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Affiliation(s)
- Jiaquan Yuan
- Department of Materials Science and Engineering, National University of Singapore, 7 Engineering Drive 1, 117574, Singapore
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33
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Lim SI, Ojea-Jiménez I, Varon M, Casals E, Arbiol J, Puntes V. Synthesis of platinum cubes, polypods, cuboctahedrons, and raspberries assisted by cobalt nanocrystals. NANO LETTERS 2010; 10:964-73. [PMID: 20143792 DOI: 10.1021/nl100032c] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The introduction of metallic traces into the synthesis of platinum nanocrystals (Pt NCs) has been investigated as a surfactant-independent means of controlling shape. Various nanocrystal morphologies have been produced without modification of the reaction conditions, composition, and concentration other than the presence of cobalt traces (<5%). In the presence of metallic cobalt (a strong reducer for Pt cations) cubic Pt NCs are obtained, while cobalt ions or gold NCs have no effect on the synthesis, and as a result, polypods are obtained. Intermediate shapes such as cemented cubes or cuboctahedron NCs are also obtained under similar conditions. Thus, various NC shapes can be obtained with subtle changes, which illustrates the high susceptibility and mutability of the NC shape to modification of the reaction kinetics during the early reduction process. Our studies help progress toward a general mechanism for nanocrystal shape control.
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34
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Chen A, Holt-Hindle P. Platinum-Based Nanostructured Materials: Synthesis, Properties, and Applications. Chem Rev 2010; 110:3767-804. [DOI: 10.1021/cr9003902] [Citation(s) in RCA: 1154] [Impact Index Per Article: 82.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Aicheng Chen
- Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada
| | - Peter Holt-Hindle
- Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada
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35
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Watt J, Cheong S, Toney MF, Ingham B, Cookson J, Bishop PT, Tilley RD. Ultrafast growth of highly branched palladium nanostructures for catalysis. ACS NANO 2010; 4:396-402. [PMID: 20028103 DOI: 10.1021/nn901277k] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Palladium is widely used as a catalyst in pharmaceutical and chemical syntheses as well as in the reduction of harmful exhaust emissions. Therefore, the development of high performance palladium catalysts is an area of major concern. In this paper, we present the synthesis of highly branched palladium nanostructures in a simple solution phase reaction at room temperature. By varying the nature of the organic stabilizer system we demonstrate control over the reaction kinetics and hence the shape of the nanostructures. Investigations into the structural evolution of the nanostructures show that they form from multiply twinned face centered cubic (fcc) nanoparticle nuclei. Reaction kinetics then determine the resulting shape where ultrafast growth is shown to lead to the highly branched nanostructures. These results will contribute greatly to the understanding of complex nanoparticle growth from all fcc metals. The nanostructures then show excellent catalytic activity for the hydrogenation of nitrobenzene to aniline.
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Affiliation(s)
- John Watt
- Victoria University of Wellington MacDiarmid Institute of Advanced Materials and Nanotechnology, Kelburn Pde, Wellington, New Zealand
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36
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Cheong S, Watt J, Ingham B, Toney MF, Tilley RD. In Situ and Ex Situ Studies of Platinum Nanocrystals: Growth and Evolution in Solution. J Am Chem Soc 2009; 131:14590-5. [DOI: 10.1021/ja9065688] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Soshan Cheong
- School of Chemical and Physical Sciences and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington 6012, New Zealand, Industrial Research Limited, P.O. Box 31-310, Lower Hutt 5040, New Zealand, and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025
| | - John Watt
- School of Chemical and Physical Sciences and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington 6012, New Zealand, Industrial Research Limited, P.O. Box 31-310, Lower Hutt 5040, New Zealand, and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025
| | - Bridget Ingham
- School of Chemical and Physical Sciences and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington 6012, New Zealand, Industrial Research Limited, P.O. Box 31-310, Lower Hutt 5040, New Zealand, and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025
| | - Michael F. Toney
- School of Chemical and Physical Sciences and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington 6012, New Zealand, Industrial Research Limited, P.O. Box 31-310, Lower Hutt 5040, New Zealand, and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025
| | - Richard D. Tilley
- School of Chemical and Physical Sciences and The MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, Wellington 6012, New Zealand, Industrial Research Limited, P.O. Box 31-310, Lower Hutt 5040, New Zealand, and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025
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37
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Wang S, Kristian N, Jiang S, Wang X. Controlled synthesis of dendritic Au@Pt core-shell nanomaterials for use as an effective fuel cell electrocatalyst. NANOTECHNOLOGY 2009; 20:025605. [PMID: 19417274 DOI: 10.1088/0957-4484/20/2/025605] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report the controlled synthesis of dendritic Au@Pt core-shell nanomaterials. The size and morphology of the Au cores and the Pt shell thickness of the Au@Pt core-shell nanostructures could be easily tuned. It was found that the directing agent and the reducing agent play critical roles in the synthesis of dendritic Au@Pt core-shell nanomaterials. For comparison purposes, conventional Au@Pt core-shell nanoparticles and monometallic Pt nanoparticles were also synthesized by the successive reduction method. Transmission electron microscopy (TEM) observations demonstrated the dendritic surface of the products obtained. The UV-visible (UV-vis) spectroscopy results and a comparison of the average diameter between the dendritic Au@Pt and conventional Au@Pt confirmed the relatively loose Pt shells around Au cores for the dendritic Au@Pt. The as-prepared dendritic Au@Pt showed enhanced electrocatalytic activity for methanol oxidation in acid medium, compared to the conventional Au@Pt and monometallic Pt.
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Affiliation(s)
- Shuangyin Wang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore
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38
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Zhang HT, Ding J, Chow GM, Dong ZL. Engineering inorganic hybrid nanoparticles: tuning combination fashions of gold, platinum, and iron oxide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:13197-13202. [PMID: 18925758 DOI: 10.1021/la802805w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Multistep colloidal chemical routes were employed to synthesize Pt/Au, Pt/iron oxide (IO), and Au/Pt/IO hybrid nanoparticles (NPs). The starting templates, Pt NPs, were synthesized by controlling the decomposition kinetics of platinum acetylacetonate in oleylamine. The morphologies of binary metal Pt/Au hybrid NPs were modulated by controllable attachment of Au nanoscale domains to Pt templates. Similarly, Pt/IO and Au/Pt/IO hybrid NPs were fabricated by the controllable attachment of Fe to the Pt or Pt/Au template NPs. The noble metal domains of as-prepared hybrid NPs had face center cubic crystal structures and did not alloy, as verified by high resolution transmission electron microscopy and X-ray diffraction spectrometry. X-ray diffraction spectrometry study indicates that the IO domains in the as-prepared NPs have a spinel structure. UV-vis study of binary metal Pt/Au hybrid NPs revealed that they have a characteristic plasmon resonance around 525 nm, while dumbbell-like Au/Pt/IO NPs had a plasmon resonance around 600 nm. Furthermore, magnetism study of the binary Pt-IO NPs clearly indicated that the interfacial interactions between Pt and IO domains could result in a shift of the blocking temperature.
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Affiliation(s)
- Hai-Tao Zhang
- Department of Materials Science and Engineering, Faculty of Engineering, National University of Singapore, Singapore 117574.
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