Semiconductor nanowires are being actively investigated because of their unique physical properties and potential applications in nanoelectronics and optoelectronic devices. However, current hurdles for device integration include the lack of control over the orientation, location, and packing density of nanowires. This communication presents for the first time the use of a unique, bottom-up approach for the catalyzed growth of semiconductor nanowires via biological templating. High-density, vertically oriented growth of Ge nanowires with monodispersed diameters and spacings was achieved through patterning of very small sized (5-20 nm) Au nanoparticles using bacterial surface-layer proteins as a template. We envision the applicability of this biotemplating approach to a variety of nanowires and substrate materials. 相似文献
The high-bias electrical transport properties of suspended metallic single-walled carbon nanotubes (SWNTs) are investigated at various temperatures in vacuum, in various gases, and when coated with molecular solids. It is revealed that nonequilibrium optical phonon effects in suspended nanotubes decrease as the ambient temperature increases. Gas molecules surrounding suspended SWNTs assist the relaxation of hot phonons and afford enhanced current flow along nanotubes. Molecular solids of carbon dioxide frozen onto suspended SWNTs quench the nonequilibrium phonon effect. The discovery of strong environmental effects on high current transport in nanotubes is important to high performance nanoelectronics applications of 1D nanowires in general. 相似文献
Developing simple, rapid, and environmentally friendly synthetic methodologies for the preparation of functional nanomaterials is of great importance for broadening and improving their potential applications. In comparison with other methods, the microwave-assisted hydrothermal method possesses and combines the merits of microwave and hydrothermal methods, which can achieve the high temperature and high pressure for a short time from several minutes to several hours in a closed reaction system. In this review, the synthesis of various types of functional nanomaterials such as metals oxides, metal composite oxides, inorganic biomaterials (hydroxyapatite and calcium carbonate), and metal sulfides via the microwave-assisted hydrothermal method is summarized. The special properties and applications of functional nanomaterials by the microwave-assisted hydrothermal method are compared with others methods. The future developments of this promising method are put forward. 相似文献
We review recent developments in our group regarding the solution-phase synthesis of one-dimensional nanostructures of metals. The synthetic approaches include solution-liquid-solid growth for nanowires of low-melting-point metals such as Pb; seed-directed growth for Ag nanowires, nanobeams, and nanobelts; kinetically controlled growth for Pt nanorods, nanowires, and multipods; and galvanic replacement for nanotubes of Au, Pt, and Pd. Both characterization and mechanistic studies are presented for each nanostructure. Finally, we highlight the electrical and plasmonic properties of these metal nanostructures and discuss their potential applications in nanoscale devices. 相似文献
The concept of assembling electronic circuits from metal nanowires is discussed. These nanowires are synthesised electrochemically by using porous membranes as templates. High aspect ratio wires, which range from 15 to 350 nm in diameter and contain "stripes" of different metals, semiconductors, colloid/polymer multilayers, and self-assembling monolayers have been made by this technique. By using the distinct surface chemistry of different stripes, the nanowires can be selectively derivatized and positioned on patterned surfaces. This allows the current-voltage properties of single and crossed nanowire devices to be measured. Nanowire conductors, rectifiers, switches, and photoconductors have been characterized. Techniques are still being developed for assembling sublithographic scale nanowires into cross-point arrays for memory and logic applications. 相似文献
With the development of nanotechnology, there is a growing demand for advanced electronics based on functional nanomaterials. In this respect, owing to their unique properties, conducting polymers (CP) synthesized in the form of one‐dimensional (1D) nanostructures are of particular interest. In this feature paper, we first report one of the most powerful techniques, the hard templating synthesis, for elaborating a large number of uniform 1D CP nanotubes or nanowires with precise control over lengths and diameters. Then, recent advances in the preparation, through electrochemical template synthesis, of various multi‐segmented nanowires containing a combination of metallic and polymeric components are discussed. Hybrid metal‐CP nanowires are promising high tech materials as they exhibit enhanced performances compared to their bulk counterparts and are of direct interest for developing novel multifunctional systems for a wide range of applications. Finally, some future directions for research in the area of multi‐segmented nanowires are proposed.
We review recent advances in biosensors based on one‐dimensional (1‐D) nanostructure field‐effect transistors (FET). Specifically, we address the fabrication, functionalization, assembly/alignment and sensing applications of FET based on carbon nanotubes, silicon nanowires and conducting polymer nanowires. The advantages and disadvantages of various fabrication, functionalization, and assembling procedures of these nanosensors are reviewed and discussed. We evaluate how they have been used for detection of various biological molecules and how such devices have enabled the achievement of high sensitivity and selectivity with low detection limits. Finally, we conclude by highlighting some of the challenges researchers face in the 1‐D nanostructures research arena and also predict the direction toward which future research in this area might be directed. 相似文献
Nanoparticles are the focus of much attention due to their astonishing properties and numerous possibilities for applications in nanotechnology. For realising versatile functions, assembly of nanoparticles in regular patterns on surfaces and at interfaces is required. Assembling nanoparticles generates new nanostructures, which have unforeseen collective, intrinsic physical properties. These properties can be exploited for multipurpose applications in nanoelectronics, spintronics, sensors, etc. This review surveys different techniques, currently employed and being developed, for assembling nanoparticles in to ordered nanostructures. In this endeavour, the principles and methods involved in the development of assemblies are discussed. Subsequently, different possibilities of nanoparticle‐based nanostructures, obtained in multi‐dimensions, are presented. 相似文献