Nanostructures one-dimensional

The second class of nanoscale building blocks, referred to as ID nanostructures, is reserved for those materials that have nanoscale dimensions that are equivalent in all but one direction. For instance, let us consider the 2D architecture of this page. Recall that a OD nanostructure is analogous to the period following this sentence (length = width) a ID nanostructure is analogous to the number 1 (length width). 

Hlgh-resolution transmission declron microscopy (HRTEM) 

The tunable electronic properties of CNTs are being explored for next-generation IC architectures. As you may recall from Chapter 4, traditional Si-based microelectronic devices will likely reach a fundamental limit within the next decade or so, necessitating the active search for replacement materials. Accordingly, an area of intense investigation is molecular electronics - in which the electronic device is built from the placement of individual molecules.Not surprisingly, the interconnects of these devices will likely be comprised of CNTs and other (semi)conductive ID nanostructures such as nanowires. 

Nanoscale Building Blocks and Applications Armchair nanotube (5,5) 

The desirable mechanical properties of CNTs have been exploited in recent years for the structural reinforcement of polymers.This is a natural extension of traditional composite materials used for applications that require both high-strength 

A nanotube is a 1-D structure that contains a hollow core, whereas the other three nanoarchitectures are solid throughout. The term nanofiber should be reserved for 1-D nanostructures that are amorphous (and usually nonconductive) such as polymers and other non-graphitized carbonaceous structures. By contrast, a nanowire designates a structure that is crystalline, with either metallic or semiconductive electrical properties. 

A nanorod is typically a crystalline 1-D nanostructure, with an overall length comparable to its width (i.e., both dimensions are 100 nm). As their name implies, another feature of nanorods is their rigid sidewall structures. However, since crystalline nanorods exhibit the same overall shape as needle-like bulk crystals, the term nanocrystal is probably more appropriate for these structures (or, more explicitly rod-like nanocrystals ). Whereas nanowires, nanofibers, and nanotubes exhibit an interwoven array, nanorods are completely linear in morphology. As such, nanorods are capable of stacking onto each other to yield interesting 2-D and 3-D arrays - not usually as easy to perform with the spaghetti-like morphology of the other 1-D nanostrucmres. 

In addition to the above tunable conductive properties, CNTs are the strongest and stiffest materials known to date (Table 6.6). The hollow, closed morphology of 

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Lieber CM (1998) One-dimensional nanostructures chemistry, physics and applications. Solid State Commun 107 607... 

Huang, J., Xia, C., Cao, L. and Zeng, X. (2008) Facile microwave hydrothermal synthesis of zinc oxide one-dimensional nanostructure with three-dimensional morphology. Materials Science and Engineering B, 150, 187-193. 

Zhou, Y. and Shimizu, T. (2008) Lipid nanotubes a unique template to create diverse one-dimensional nanostructures. Chemistry of Materials, 20 (3), 625-633. Nogawa, K., Tagawa, Y., Nakajima, M., Arai, F., Shimizu, T., Kamiya, S. and Fukuda, T. (2007) Development of novel nanopipette with a lipid nanotube as nanochannel. Journal of Robotics and Mechatronics, 19 (5), 528-534. 

We use the same approach to classify the different nanostructures for Titania. The term one-dimensional (ID) nanostructures indicate nanocrystals in which elongation only in one direction is above this threshold (about 10 nm). This class of ID nanostructures comprises different types of nano-ordered materials, such as nanorods, -wires, -coils, -fibers, -pillars (or -columns) and -tubes. We prefer to use the term quasi one-dimensional nanostructures, because often the dimensions are larger than the indicated threshold, although elongation along one main axis still exists. When the diameter of the nanorod, nanowire or nanotube becomes smaller, there is often a significant change in the properties with respect to crystalline solids or even two-dimensional systems. A bismuth nanowire is an excellent example, which transforms into a semiconductor, as the wire diameter becomes smaller.145... 

One-dimensional nanostructures of chalcogens and chalcogenides. An overview of solution-phase methods for generating one-dimensional nanostructures of chalcogens and chalcogenides has been presented by Mayers et al. (2004). Attention was especially focused on Se and Te because of their characteristic crystal structures and their catenation tendency. Basically, reactions were considered such as ... 

Poudel, P. Qiao, Q., One dimensional nanostructure/nanoparticle composites as photoanodes for dye-sensitized solar cells. Nanoscale 2012,4 2826-2838. 

Recently, carbon nanotubes, an important class of one-dimensional nanostructures, have been fabricated within the pores of anodic alumina via CVD (Davydov et al, 1999 Li et al, 1999 Iwasaki et al., 1999 Suh et al, 1999). A small amount of metal (e.g., Co) is first electrochemically deposited on the bottom of the pores as a catalyst for the carbon nanotube growth, and the template is heated to 700 to 800°C in a flowing gas mixture of N2 and acetylene or ethylene. The hydrocarbon molecules are then pyrolyzed to... 

Centi G, Passalacqua R, Perathoner S, Su DS, Weinberg G, Schlogl R. Oxide thin films based on ordered arrays of one-dimensional nanostructure. A possible approach toward bridging material gap in catalysis. Phys Chem Chem Phys. 2007 9 4930-8. 

PbSe and cubic ZnS nanowires as well as complex one-dimensional nanostructures can be obtained in solution through oriented attachment of na ocryslals. "U4, In Fig. 23, star-shaped PbSe uanocrystals and branched nanowircs are shown. 

The chemical methods for the preparation of nanomaterial could be categorized as either template-directed or template-free. The template synthesis methods commonly used for the production of one-dimensional nanostructured PANI are further subdivided into hard template (physical template) synthesis and soft template (chemical template) synthesis approach according to the solubility of the templates in the reaction media. Non-template routes for the synthesis of one-dimensional nanostructured PANI such as rapid-mixing reaction method, radiolytic synthesis, interfacial polymerization, and sonochemical synthesis have also been reported [56], Other approaches like combined soft and hard template synthesis are also known. An overview of hard-template, soft-template, and template-free procedures are presented in the following paragraphs. 

Over the past two decades, enormous progress has been achieved in the synthesis, characterization and device applications of nanostructured Ti02. Among the various types of nanostructured Ti02, the quasi-one-dimensional nanostructure has attracted particular attention. This chapter will give a comprehensive review on the synthesis of this quasi-one-dimensional Ti02 nanostructure by electrochemical anodization method, the characterization of its properties, and its potential for applications. 

There exist a variety of methods to synthesize quasi-one-dimensional nanostructured materials, which include but not limited to vapor phase growth, template-assisted synthesis, sol-gel deposition, surfactant-assisted growth, sonochemical method, hydrothermal method, and electrochemical deposition [21], Among the various methods, the electrochemical anodization method is one of the simplest and cheapest methods to synthesize ordered quasi-one-dimensional nanostructure. 

Yang PD, Rim F (2002) Langmuir-Blodgett assembly of one-dimensional nanostructures. Chemphyschem 3 503-506... 

T. Sako, G.H.F. Diercksen, Understanding the spectra of a few electrons confined in a quasi-one-dimensional nanostructure, J. Phys. Condens. Matter 20 (2008) 155202 (13p). 

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