301
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Gu H, Zheng R, Liu H, Zhang X, Xu B. Direct synthesis of a bimodal nanosponge based on FePt and ZnS. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2005; 1:402-6. [PMID: 17193463 DOI: 10.1002/smll.200400106] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Affiliation(s)
- Hongwei Gu
- Department of Chemistry, The Hong Kong University of Science & Technology, Clear Water Bay, Hong Kong, China
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302
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Love JC, Estroff LA, Kriebel JK, Nuzzo RG, Whitesides GM. Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology. Chem Rev 2005; 105:1103-69. [PMID: 15826011 DOI: 10.1021/cr0300789] [Citation(s) in RCA: 4689] [Impact Index Per Article: 246.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- J Christopher Love
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA
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303
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Bao Y, Beerman M, Pakhomov AB, Krishnan KM. Controlled Crystalline Structure and Surface Stability of Cobalt Nanocrystals. J Phys Chem B 2005; 109:7220-2. [PMID: 16851825 DOI: 10.1021/jp044363n] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of monodispersed 10 nm cobalt nanocrystals with controlled crystal morphology and investigation of the surface stability of these nanocrystals are described. Depending on the surfactants used, single crystalline or multiple grain nanocrystals can be reproducibly produced. The relative surface stability of these nanocrystals is analyzed using the temperature dependences of the dc magnetic susceptibility. The novel method, which allows sensitive monitoring of the surface stability, is based on the observation that, with particle oxidation, an anomalous peak appears at 8 K in zero-field-cooled magnetization measurements. It is found that the surfactant protective layer is more important for long-term stability at room temperature, while the high-temperature oxidation rate is controlled by the crystal morphology of the nanoparticles.
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Affiliation(s)
- Yuping Bao
- Materials Science & Engineering, University of Washington, Seattle, Washington 98195, USA
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304
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Manna L, Wang LW, Cingolani R, Alivisatos AP. First-Principles Modeling of Unpassivated and Surfactant-Passivated Bulk Facets of Wurtzite CdSe: A Model System for Studying the Anisotropic Growth of CdSe Nanocrystals. J Phys Chem B 2005; 109:6183-92. [PMID: 16851684 DOI: 10.1021/jp0445573] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Equilibrium geometries, surface energies, and surfactant binding energies are calculated for selected bulk facets of wurtzite CdSe with a first-principles approach. Passivation of the surface Cd atoms with alkyl phosphonic acids or amines lowers the surface energy of all facets, except for the polar 000 facet. On the nonpolar facets, the most stable configuration corresponds to full coverage of surface Cd atoms with surfactants, while on the polar 0001 facet it corresponds only to a partial coverage. In addition, the passivated surface energies of the nonpolar facets are in general lower than the passivated polar 0001 facet. Therefore, the polar facets are less stable and less efficiently passivated than the nonpolar facets, and this can rationalize the observed anisotropic growth mechanism of wurtzite nanocrystals in the presence of suitable surfactants.
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Affiliation(s)
- Liberato Manna
- National Nanotechnology Lab of INFM, Via Arnesano Km 5, 73100 Lecce, Italy.
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305
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Li LS, Stupp SI. One-Dimensional Assembly of Lipophilic Inorganic Nanoparticles Templated by Peptide-Based Nanofibers with Binding Functionalities. Angew Chem Int Ed Engl 2005; 44:1833-6. [PMID: 15723434 DOI: 10.1002/anie.200462142] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Liang-shi Li
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
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306
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Li LS, Stupp SI. One-Dimensional Assembly of Lipophilic Inorganic Nanoparticles Templated by Peptide-Based Nanofibers with Binding Functionalities. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200462142] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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307
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Song SY, Ma JF, Yang J, Cao MH, Li KC. Selected-Control Synthesis of Metal Phosphonate Nanoparticles and Nanorods. Inorg Chem 2005; 44:2140-2. [PMID: 15792447 DOI: 10.1021/ic048436t] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
By surfactant-assisted methods, nanoscale Co(O3PC6H5).H2O species of different morphologies, namely, nanoparticles and nanorods, have been successfully synthesized and characterized. Upon removal of the organic part of the compound, peculiar Co2P2O7 porous nanorods formed.
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Affiliation(s)
- Shu-Yan Song
- Department of Chemistry, Northeast Normal University, Changchun 130024, PR China
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308
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A new and facile route to ultrafine nanowires, superthin flakes and uniform nanodisks of nickel hydroxide. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.01.121] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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309
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Kudera S, Carbone L, Casula MF, Cingolani R, Falqui A, Snoeck E, Parak WJ, Manna L. Selective growth of PbSe on one or both tips of colloidal semiconductor nanorods. NANO LETTERS 2005; 5:445-449. [PMID: 15755092 DOI: 10.1021/nl048060g] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
PbSe nanocrystals with rock-salt structure are grown on the tips of colloidal CdS and CdSe nanorods. The facets of wurtzite rods provide a substrate with various degrees of reactivity for the growth of PbSe. The presence of dangling Cd bonds may explain subtle differences between nonequivalent facets resulting in the selective nucleation of PbSe only on one of the two tips of each CdS rod. This approach has the potential to facilitate the fabrication of heterostructures with tailored optical and electronic properties.
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Affiliation(s)
- Stefan Kudera
- Center for Nanoscience, Ludwig Maximilians Universität München, Munich, Germany
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310
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Maye MM, Lim IIS, Luo J, Rab Z, Rabinovich D, Liu T, Zhong CJ. Mediator−Template Assembly of Nanoparticles. J Am Chem Soc 2005; 127:1519-29. [PMID: 15686385 DOI: 10.1021/ja044408y] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability to construct size- and shape-controllable architectures using nanoparticles as building blocks is essential for the exploration of nanoparticle-structured properties. This paper reports findings of an investigation of a mediator-template strategy for the size-controllable assembly of nanoparticles. This strategy explores multidentate thioether ligands as molecular mediators and tetraalkylammonium-capped gold nanoparticles (5 nm) as templates toward the preparation of size-controllable and monodispersed spherical assemblies ( approximately 20-300-nm diameters). The combination of the mediation force of the multidentate thioether and the hydrophobic force of the tetraalkylammonium template establishes the interparticle linkage and stability. The morphological properties of the spherical assemblies have been characterized using TEM, AFM, and SAXS techniques. The finding of the soft-hard nature of the nanoparticle assemblies and their interactions with contacting substrates could form the basis of a new strategy for manipulating nanoscale linkages between nanoparticle assemblies, soldering nanoelectronics, and constructing nanosensor devices. The intriguing light scattering and optical absorption properties in response to assembly, disassembly, sizing, and interparticle spacing parameters have been characterized by dynamic light scattering and spectrophotometric measurements. The discovery of the controlled disassembly into individual nanoparticles and the size regulation by a third capping component could form the basis for applications in controlled drug delivery. The fundamental basis for the mediator-template strategy as a versatile assembly technique is further discussed in terms of experimental and theoretical correlations of the morphological and optical properties.
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Affiliation(s)
- Mathew M Maye
- Department of Chemistry, State University of New York at Binghamton, Binghamton, NY 13902, USA
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311
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Zhang W, Xu L, Tang K, Li F, Qian Y. Solvothermal Synthesis of NiS 3D Nanostructures. Eur J Inorg Chem 2005. [DOI: 10.1002/ejic.200400625] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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312
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Abstract
Organometallic strategies normally employed for the production of semiconductor quantum dots have been successfully applied to the synthesis of metal nanoparticles. By controlling parameters such as capping agents, reaction temperature and precursor chemistry, precise nanostructures can be obtained that exhibit highly desirable magnetic, optical and catalytic properties.
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Affiliation(s)
- Mark Green
- Department of Physics, King's College London, Strand, London, UKWC2R 2LS.
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313
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314
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Medda SK, De S, De G. Synthesis of Au nanoparticle doped SiO2–TiO2 films: tuning of Au surface plasmon band position through controlling the refractive index. ACTA ACUST UNITED AC 2005. [DOI: 10.1039/b506399j] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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315
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Pellegrino T, Kudera S, Liedl T, Muñoz Javier A, Manna L, Parak WJ. On the development of colloidal nanoparticles towards multifunctional structures and their possible use for biological applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2005; 1:48-63. [PMID: 17193348 DOI: 10.1002/smll.200400071] [Citation(s) in RCA: 217] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
In this Review, we describe the synthesis of high-quality colloidal nanoparticles in organic solvents, the mechanisms by which they can be transferred into aqueous solution, and some of their applications in biology. In particular, we will place emphasis on the creation of multifunctional nanoparticles or nanoparticle assemblies.
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Affiliation(s)
- Teresa Pellegrino
- Center for Nanoscience, Ludwig Maximilians Universität München, Munich, Germany
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316
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317
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Xu R, Zeng HC. Self-generation of tiered surfactant superstructures for one-pot synthesis of Co3O4 nanocubes and their close- and non-close-packed organizations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:9780-9790. [PMID: 15491215 DOI: 10.1021/la049164+] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Self-generation of ionic organic capping from nonionic surfactant polyoxyethylene (20) sorbitan trioleate (Tween-85) has been realized for the controlled synthesis of single crystalline Co(3)O(4) quantum dots (3.0-5.7 nm) in cubic morphology from related layered hydroxide precursors at 80-95 degrees C. With chemical modification of hydrophobic functional groups on the surface of Co(3)O(4) nanocubes; furthermore, various nanocube-containing micellar superstructures can be further assembled through hydrophobic interactions between Tween-85 molecules and the surface coating under "one-pot" conditions. In particular, square arrangements, spherical domains, and line-assemblies of the prepared Co(3)O(4) nanocubes and their inter-transformations have been attained for the first time by manipulating intersurfactant-interactions. Hydrolysis of Tween-85 and the resultant tiered surfactant superstructures have been investigated with FTIR/UV-vis/EA/TGA/DTA/XPS methods, and the capping species has been identified to be alkylated oleic carboxylate anions derived from Tween-85. Pronounced quantum confinement effects have been observed with the prepared Co(3)O(4) nanocubes, and the optical band gap energies determined are 3.95 and 2.13 eV, respectively, for O(2-)--> Co(2+) and O(2-)--> Co(3+) charge-transfer processes.
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Affiliation(s)
- Rong Xu
- Institute of Chemical and Engineering Sciences, Block 28, Ayer Rajah Crescent, Singapore 139959
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318
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Abstract
In this paper, we report a colloidal synthesis of high-quality, square, plate-shaped Gd2O3 nanocrystals. These nanoplates are single crystalline with a thickness of the Gd2O3 unit-cell edge length, approaching the lower limit of crystal growth.
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Affiliation(s)
- Y Charles Cao
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
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319
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Li Y, Li X, Yang C, Li Y. Ligand-Controlling Synthesis and Ordered Assembly of ZnS Nanorods and Nanodots. J Phys Chem B 2004. [DOI: 10.1021/jp0489018] [Citation(s) in RCA: 158] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Yunchao Li
- Key Laboratory of Organic Solids, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
| | - Xiaohong Li
- Key Laboratory of Organic Solids, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
| | - Chunhe Yang
- Key Laboratory of Organic Solids, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
| | - Yongfang Li
- Key Laboratory of Organic Solids, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
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320
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A facile route for high-throughput formation of single-crystal α-Fe2O3 nanodisks in aqueous solutions of Tween 80 and triblock copolymer. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.07.102] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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321
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Kang E, Park J, Hwang Y, Kang M, Park JG, Hyeon T. Direct Synthesis of Highly Crystalline and Monodisperse Manganese Ferrite Nanocrystals. J Phys Chem B 2004. [DOI: 10.1021/jp049041y] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eunae Kang
- National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea, Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea, and Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-742, Korea
| | - Jongnam Park
- National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea, Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea, and Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-742, Korea
| | - Yosun Hwang
- National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea, Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea, and Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-742, Korea
| | - Misun Kang
- National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea, Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea, and Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-742, Korea
| | - Je-Geun Park
- National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea, Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea, and Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-742, Korea
| | - Taeghwan Hyeon
- National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea, Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea, and Center for Strongly Correlated Materials Research, Seoul National University, Seoul 151-742, Korea
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322
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Kanehara M, Oumi Y, Sano T, Teranishi T. Syntheses of the Novel Acidic and Basic Ligands and Superlattice Formation from Gold Nanoparticles through Interparticle Acid–Base Interaction. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2004. [DOI: 10.1246/bcsj.77.1589] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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323
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Xu C, Xu K, Gu H, Zheng R, Liu H, Zhang X, Guo Z, Xu B. Dopamine as A Robust Anchor to Immobilize Functional Molecules on the Iron Oxide Shell of Magnetic Nanoparticles. J Am Chem Soc 2004; 126:9938-9. [PMID: 15303865 DOI: 10.1021/ja0464802] [Citation(s) in RCA: 583] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report on the use of dopamine (DA) as a robust molecular anchor to link functional molecules to the iron oxide shell of magnetic nanoparticles. Using nitrilotriacetic acid (NTA) as the functional molecule, we created a system with an M/Fe2O3-DA-NTA (M = Co or SmCo5.2) nanostructure, which possesses high stability and specificity for separating histidine-tagged proteins. The well-established biocompatibility of iron oxide and the robust covalent bonds between DA and Fe2O3 render this strategy attractive for constructing biofunctional magnetic nanoparticles containing iron oxide.
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Affiliation(s)
- Chenjie Xu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
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324
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Pradhan N, Efrima S. Supercrystals of Uniform Nanorods and Nanowires, and the Nanorod-to-Nanowire Oriented Transition. J Phys Chem B 2004. [DOI: 10.1021/jp0496708] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Narayan Pradhan
- Department of Chemistry and the Ilse Katz Center for Meso and Nanoscale Science and Technology, Ben Gurion University of the Negev, Beer-Sheva, Israel 84105
| | - Shlomo Efrima
- Department of Chemistry and the Ilse Katz Center for Meso and Nanoscale Science and Technology, Ben Gurion University of the Negev, Beer-Sheva, Israel 84105
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325
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Yin Y, Rioux RM, Erdonmez CK, Hughes S, Somorjai GA, Alivisatos AP. Formation of Hollow Nanocrystals Through the Nanoscale Kirkendall Effect. Science 2004; 304:711-4. [PMID: 15118156 DOI: 10.1126/science.1096566] [Citation(s) in RCA: 1757] [Impact Index Per Article: 87.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Hollow nanocrystals can be synthesized through a mechanism analogous to the Kirkendall Effect, in which pores form because of the difference in diffusion rates between two components in a diffusion couple. Starting with cobalt nanocrystals, we show that their reaction in solution with oxygen and either sulfur or selenium leads to the formation of hollow nanocrystals of the resulting oxide and chalcogenides. This process provides a general route to the synthesis of hollow nanostructures of a large number of compounds. A simple extension of the process yielded platinum-cobalt oxide yolk-shell nanostructures, which may serve as nanoscale reactors in catalytic applications.
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Affiliation(s)
- Yadong Yin
- Department of Chemistry, University of California at Berkeley, and Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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326
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Chen S, Carroll DL. Silver Nanoplates: Size Control in Two Dimensions and Formation Mechanisms. J Phys Chem B 2004. [DOI: 10.1021/jp031077n] [Citation(s) in RCA: 218] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Sihai Chen
- School of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634-0971, and Center for Nanotechnology, Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27109-7507
| | - David L. Carroll
- School of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634-0971, and Center for Nanotechnology, Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27109-7507
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327
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Puntes VF, Gorostiza P, Aruguete DM, Bastus NG, Alivisatos AP. Collective behaviour in two-dimensional cobalt nanoparticle assemblies observed by magnetic force microscopy. NATURE MATERIALS 2004; 3:263-8. [PMID: 15048109 DOI: 10.1038/nmat1094] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2003] [Accepted: 02/10/2004] [Indexed: 05/13/2023]
Abstract
The use of magnetic nanoparticles in the development of ultra-high-density recording media is the subject of intense research. Much of the attention of this research is devoted to the stability of magnetic moments, often neglecting the influence of dipolar interactions. Here, we explore the magnetic microstructure of different assemblies of monodisperse cobalt single-domain nanoparticles by magnetic force microscopy and magnetometric measurements. We observe that when the density of particles per unit area is higher than a determined threshold, the two-dimensional self-assemblies behave as a continuous ferromagnetic thin film. Correlated areas (similar to domains) of parallel magnetization roughly ten particles in diameter appear. As this magnetic percolation is mediated by dipolar interactions, the magnetic microstructure, its distribution and stability, is strongly dependent on the topological distribution of the dipoles. Thus, the magnetic structures of three-dimensional assemblies are magnetically soft, and an evolution of the magnetic microstructure is observed with consecutive scans of the microscope tip.
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Affiliation(s)
- Victor F Puntes
- Physics Department, University of Barcelona, 08028 Barcelona, Spain.
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328
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Jun YW, Casula MF, Sim JH, Kim SY, Cheon J, Alivisatos AP. Surfactant-assisted elimination of a high energy facet as a means of controlling the shapes of TiO2 nanocrystals. J Am Chem Soc 2004; 125:15981-5. [PMID: 14677990 DOI: 10.1021/ja0369515] [Citation(s) in RCA: 284] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The surfactant-mediated shape evolution of titanium dioxide anatase nanocrystals in nonaqueous media was studied. The shape evolves from bullet and diamond structures to rods and branched rods. The modulation of surface energies of the different crystallographic faces through the use of a surface selective surfactant is the key parameter for the shape control.
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Affiliation(s)
- Young-Wook Jun
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, , USA
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329
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Niu H, Chen Q, Ning M, Jia Y, Wang X. Synthesis and One-Dimensional Self-Assembly of Acicular Nickel Nanocrystallites under Magnetic Fields. J Phys Chem B 2004. [DOI: 10.1021/jp0361172] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Helin Niu
- The Structure Research Laboratory and Department of Materials Science & Engineering, University of Science & Technology of China, Hefei 230026, China
| | - Qianwang Chen
- The Structure Research Laboratory and Department of Materials Science & Engineering, University of Science & Technology of China, Hefei 230026, China
| | - Min Ning
- The Structure Research Laboratory and Department of Materials Science & Engineering, University of Science & Technology of China, Hefei 230026, China
| | - Yaoshun Jia
- The Structure Research Laboratory and Department of Materials Science & Engineering, University of Science & Technology of China, Hefei 230026, China
| | - Xiaojuan Wang
- The Structure Research Laboratory and Department of Materials Science & Engineering, University of Science & Technology of China, Hefei 230026, China
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330
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Dumestre F, Chaudret B, Amiens C, Renaud P, Fejes P. Superlattices of iron nanocubes synthesized from Fe[N(SiMe3)2]2. Science 2004; 303:821-3. [PMID: 14764874 DOI: 10.1126/science.1092641] [Citation(s) in RCA: 488] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The reaction of the metal-organic precursor Fe[N(SiMe3)2]2 with H2 in the presence of a long-chain acid and a long-chain amine in various proportions produces monodisperse zerovalent iron nanoparticles. These Fe particles display magnetic properties that match those of bulk iron as evidenced by magnetic and Mössbauer measurements. The nanoparticles adopt a cubic shape with edges of 7 nanometers and are incorporated into extended crystalline superlattices containing nanocubes in close proximity and with their crystallographic axes aligned. These superlattices are formed in solution, precipitate in high yield, and may be redissolved and redeposited as two-dimensional arrays.
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Affiliation(s)
- Frédéric Dumestre
- Laboratoire de Chimie de Coordination du CNRS, 205, route de Narbonne, 31077 Toulouse Cédex 04, France
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331
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Xu C, Xu K, Gu H, Zhong X, Guo Z, Zheng R, Zhang X, Xu B. Nitrilotriacetic Acid-Modified Magnetic Nanoparticles as a General Agent to Bind Histidine-Tagged Proteins. J Am Chem Soc 2004; 126:3392-3. [PMID: 15025444 DOI: 10.1021/ja031776d] [Citation(s) in RCA: 299] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Using Nalpha,Nalpha-bis(carboxymethyl)lysine to react with FePt magnetic nanoparticles, we synthesized the FePt-NTA conjugate, which immobilizes Ni2+ ions and selectively binds to histidine-tagged proteins at concentration as low as 0.5 pM. This simple system serves as a useful alternative to existing protocols for protein separation and also acts as a versatile agent for transporting and anchoring proteins.
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Affiliation(s)
- Chenjie Xu
- Department of Chemistry, Department of Physics, and Bioengineering Program, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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332
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Banerjee IA, Yu L, Matsui H. Cu nanocrystal growth on peptide nanotubes by biomineralization: size control of Cu nanocrystals by tuning peptide conformation. Proc Natl Acad Sci U S A 2003; 100:14678-82. [PMID: 14645717 PMCID: PMC299758 DOI: 10.1073/pnas.2433456100] [Citation(s) in RCA: 225] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2003] [Indexed: 11/18/2022] Open
Abstract
With recent interest in seeking new biologically inspired device-fabrication methods in nanotechnology, a new biological approach was examined to fabricate Cu nanotubes by using sequenced histidine-rich peptide nanotubes as templates. The sequenced histidine-rich peptide molecules were assembled as nanotubes, and the biological recognition of the specific sequence toward Cu lead to efficient Cu coating on the nanotubes. Cu nanocrystals were uniformly coated on the histidine-incorporated nanotubes with high packing density. In addition, the diameter of Cu nanocrystal was controlled between 10 and 30 nm on the nanotube by controlling the conformation of histidine-rich peptide by means of pH changes. Those nanotubes showed significant change in electronic structure by varying the nanocrystal diameter; therefore, this system may be developed to a conductivity-tunable building block for microelectronics and biological sensors. This simple biomineralization method can be applied to fabricate various metallic and semiconductor nanotubes with peptides whose sequences are known to mineralize specific ions.
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Affiliation(s)
- Ipsita A Banerjee
- Department of Chemistry and Biochemistry, Hunter College and the Graduate Center, The City University of New York, 695 Park Avenue, New York, NY 10021, USA
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333
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Sigman MB, Ghezelbash A, Hanrath T, Saunders AE, Lee F, Korgel BA. Solventless Synthesis of Monodisperse Cu2S Nanorods, Nanodisks, and Nanoplatelets. J Am Chem Soc 2003; 125:16050-7. [PMID: 14677997 DOI: 10.1021/ja037688a] [Citation(s) in RCA: 224] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cu(2)S nanocrystals with disklike morphologies were synthesized by the solventless thermolysis of a copper alkylthiolate molecular precursor. The nanodisks ranged from circular to hexagonal prisms from 3 to 150 nm in diameter and 3 to 12 nm in thickness depending on the growth conditions. High resolution transmission electron microscopy (HRTEM) revealed the high chalcocite (hexagonal) crystal structure oriented with the c-axis ([001] direction) orthogonal to the favored growth direction. This disk morphology is thermodynamically favored as it allows the extension of the higher energy [100] and [110] surfaces with respect to the [001] planes. The hexagonal prism morphology also appears to relate to increased C-S bond cleavage of adsorbed dodecanethiol along the more energetic [100] facets relative to [001] facets. Monodisperse Cu(2)S nanodisks self-assemble into ribbons of stacked platelets. This solventless approach provides a new technique to synthesize anisotropic metal chalcogenide nanostructures with shapes that depend on both the face-sensitive thermodynamic surface energy and the surface reactivity.
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Affiliation(s)
- Michael B Sigman
- Department of Chemical Engineering, Texas Materials Institute, Center for Nano- and Molecular Science and Technology, The University of Texas at Austin, Austin, Texas 78712-1062, USA
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334
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De G, Rao CNR. Two-Dimensional Au and Au−Cu Alloy Nanocrystals with Orientation in (111) Plane Embedded in Glassy Silica Films. J Phys Chem B 2003. [DOI: 10.1021/jp0310091] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Goutam De
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560 064, India
| | - C. N. R. Rao
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560 064, India
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335
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Parviz B, Ryan D, Whitesides G. Using self-assembly for the fabrication of nano-scale electronic and photonic devices. ACTA ACUST UNITED AC 2003. [DOI: 10.1109/tadvp.2003.817971] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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336
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Gross AF, Diehl MR, Beverly KC, Richman EK, Tolbert SH. Controlling Magnetic Coupling between Cobalt Nanoparticles through Nanoscale Confinement in Hexagonal Mesoporous Silica. J Phys Chem B 2003. [DOI: 10.1021/jp034240n] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Adam F. Gross
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, California 90095-1569
| | - Michael R. Diehl
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, California 90095-1569
| | - Kristen C. Beverly
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, California 90095-1569
| | - Erik K. Richman
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, California 90095-1569
| | - Sarah H. Tolbert
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, California 90095-1569
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