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Journal ArticleDOI

Preparation and dispersion of Ni–Cu composite nanoparticles

Yu-Guo Guo1, Li-Jun Wan1, Jian Ru Gong1, Chunli Bai1 
01 Jul 2002-Physical Chemistry Chemical Physics (The Royal Society of Chemistry)-Vol. 4, Iss: 14, pp 3422-3424

AbstractFinely dispersed sandwich composite nanoparticles of Cu–Ni–Cu were prepared by a novel method combining template synthesis and an ultrasonic treatment method. The composite nanoparticles have uniform cylinder shape with tunable diameter and length. Transmission electron microscopy (TEM) and electron diffraction (ED) were employed to characterize the nanoparticles. This method can be used to fabricate shape- and size-controlled composite nanoparticles in a wide range of metals and other materials. The so-prepared particles may be suitable candidates as nanoscale blocks for assembling nanodevices.

Topics: Nanoparticle (54%), Electron diffraction (51%)

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Journal ArticleDOI
TL;DR: This review highlights recent advances in the synthesis of multisegmented one-dimensional nanorods and nanowires with metal, semiconductor, polymer, molecular, and even gapped components and discusses the applications of these multicomponent nanomaterials in magnetism, self-assembly, electronics, biology, catalysis, and optics.
Abstract: In the science and engineering communities, the nanoscience revolution is intensifying. As many types of nanomaterials are becoming more reliably synthesized, they are being used for novel applications in all branches of nanoscience and nanotechnology. Since it is sometimes desirable for single nanomaterials to perform multiple functions simultaneously, multicomponent nanomaterials, such as core-shell, alloyed, and striped nanoparticles, are being more extensively researched. Nanoscientists hope to design multicomponent nanostructures and exploit their inherent multiple functionalities for use in many novel applications. This review highlights recent advances in the synthesis of multisegmented one-dimensional nanorods and nanowires with metal, semiconductor, polymer, molecular, and even gapped components. It also discusses the applications of these multicomponent nanomaterials in magnetism, self-assembly, electronics, biology, catalysis, and optics. Particular emphasis is placed on the new materials and devices achievable using these multicomponent, rather than single-component, nanowire structures.

468 citations


Journal ArticleDOI
04 May 2007-Small
TL;DR: This review separates the methods into vapor-phase synthesis, solution- phase synthesis, template-based synthesis, and other approaches, such as lithography, electrospinning, and assembly, used to form a variety of heterojunctions from different combinations of semiconductor, metal, carbon, and polymeric materials.
Abstract: There are a variety of methods for synthesizing or fabricating one-dimensional (1D) nanostructures containing heterojunctions between different materials. Here we review recent developments in the synthesis and fabrication of heterojunctions formed between different materials within the same 1D nanostructure or between different 1D nanostructures composed of different materials. Structures containing 1D nanoscale heterojunctions exhibit interesting chemistry as well as size, shape, and material-dependent properties that are unique when compared to single-component materials. This leads to new or enhanced properties or multifunctionality useful for a variety of applications in electronics, photonics, catalysis, and sensing, for example. This review separates the methods into vapor-phase synthesis, solution-phase synthesis, template-based synthesis, and other approaches, such as lithography, electrospinning, and assembly. These methods are used to form a variety of heterojunctions, including segmented, core/shell, branched, or crossed, from different combinations of semiconductor, metal, carbon, and polymeric materials.

273 citations


Journal ArticleDOI
Abstract: Multisegment PtNi nanorods (Ni−Pt, Ni−Pt−Ni, Ni−Pt−Ni−Pt, and Ni−Pt−Ni−Pt−Ni) with controllable lengths of the individual metals were obtained by sequential electrodeposition of the metals into the...

98 citations


Journal ArticleDOI
TL;DR: Highly ordered Ni-Pt multilayered nanowire arrays have been fabricated using a porous anodic aluminum oxide (AAO) template by pulse electrodeposition and Magnetization measurements revealed that an array of such nanowires with 20-nm diameters has an enhanced coercivity.
Abstract: Highly ordered Ni-Pt multilayered nanowire arrays have been fabricated using a porous anodic aluminum oxide (AAO) template by pulse electrodeposition. The cylindrical Ni nanoparticles with different lengths and diameters in these arrays were characterized by transmission electron microscope (TEM) and alternating-gradient magnetometer (AGM) measurements. Magnetization measurements revealed that an array of such nanowires with 20-nm diameters has an enhanced coercivity (ca. 1169 Oe) and a high remanence ratio (ca. 0.96).

80 citations


Journal ArticleDOI
Abstract: The preparation and characterization of highly dispersed metal nanoparticles in porous anodic aluminum oxide (AAO) films are reported. Cross-linked polyacrylamide (PAM) hydrogel nanowires are prepared within the pores of an AAO template by electropolymerization of acrylamide. Metal nanoparticles are introduced into the polymer nanowires in the channels of AAO by a “breathing” mechanism whereby the shrunken polymer nanowires are allowed to swell in an aqueous solution containing metal nanoparticles, and the structures are then re-shrunk in acetone. The loading amount and distribution of nanoparticles in PAM nanowires can be controlled by varying the number of breathing cycles and modifying the breathing process as clearly seen in TEM images. Upon calcination, the nanoparticle/hydrogel composite results in highly dispersed metal nanoparticles supported in AAO. Au nanoparticles (∼12 nm diam.) and Pt nanoparticles (∼3 nm diam.) have been dispersed in PAM nanowires and the channels of AAO films and characteriz...

54 citations


References
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Journal ArticleDOI
02 Mar 2000-Nature
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4,128 citations


PatentDOI
04 Jun 2001-Science
TL;DR: A method of constructing <30-nanometer structures in close proximity with precise spacings is presented that uses the step-by-step application of organic molecules and metal ions as size-controlled resists on predetermined patterns, such as those formed by electron-beam lithography.
Abstract: The present invention is a method and apparatus relating to manufacturing nanostructure patterns and components using molecular science. The method includes overlaying a multilayer organic molecule resist on at least a portion of a parent structure selectively deposited on a substrate, depositing a layer over the parent structure and in contact with at least a portion of the multilayer organic resist, and removing the multilayer organic molecule resist to leave a residual structure.

2,297 citations