Synthesis, template-based

Template-Based Synthesis Template directed synthesis represents a convenient and versatile method for generating ID nanostructures. In this technique, the... 

Huczko A (2000) Template-based synthesis of nanomateiials. Appl Phys A 70 365-376... 

One-dimensional (1-D) nanosbuctures (b) are composed mainly of nanowires, nanorods and nanobelts. Spontaneous growth, template-based synthesis and electrospinning are considered bottom-up approaches, while lithography is a top-down technique [7, 84]. Two-dimensional (2-D) nanostructures (c) involve thin films, which have been the object of intensive study for almost a century and for which many methods have been developed and improved. 

A variety of solution methods such as seed-assisted growth, template-based synthesis, polyol method, solvothermal method and oriented attachment have also been developed for the synthesis of one-dimensional nanostructures. Here we will present various examples of the nanowires including metals, oxides, chalcogenides and pnictides with different synthetic methods. 

However, a much simpler and more efficient approach to the fabrication of three-dimensionally conductive matrices would be coating of materials in the desired geometry either electrochemically or chemically. Martin et al. [58,59] at Colorado State University have utilized the coating approach to achieve a template-based synthesis of hollow polypyrrole tubules and fibers with enhanced ionic and electronic conductivities. A high-density array of microcapsules 50... 

Template-based synthesis involves the fabrication of the desired material within the pores or channels of a nanoporous template. A template may be defined as a central structure within which a network forms in such a way that removal of the template creates a filled cavity with morphological and/or stereochemical features related to those of the template. Track-etch membranes, porous alumina, and other nanoporous structures have been characterized as templates. Electrochemical and electroless depositions, chemical polymerization, sol-gel deposition, and chemical vapor deposition have been presented as major template synthetic strategies. Template-based synthesis can be used to prepare nanostructures of conductive polymers, metals, metal oxides, semiconductors, carbons, and other solid matter... 

Huczko A (2000) Template-based synthesis of nanomaterials. Appl Phys A 70 365-376 Ihokura K, Watson J (1994) The stannic oxide Gas sensor principle and application. CRC, Boca Raton, EL Ivanovskaya M (2000) Ceramic and film metal oxide sensors obtained by sol-gel method structural features and gas-sensitive properties. Electron Technol 33(1/2) 108-112 Janata J (1989) Principle of chemical sensors. Plenum, New York, NY... 

Figure 1 Template-based synthesis of a macrocycle, showing the formation of the intermediate supramolecular complex between the template and an interacting fragment—in the key equilibrium process—followed by its covalent capture giving the prodnct-tonplate complex, which in this hypothetical case can be dissociated. Note that the template favors the formation of a cyclic tetramo- ovct any other oligomer, cyclic, or linear.

Covalent functionalization is accomplished by chemically attaching molecules to the CNT surface. In general, CNTs that lack defect sites need to undergo processes, such as sonication, add treatment, electrochanical oxidation, or plasma treatment to actually activate their surface aud provide hydrophilic surface functional groups for covalent attachment. CNTs and CNFs that have defect sites, such as those grown from template-based synthesis methods, will have some binding sites but will often require a degree of surface activation. 

One may find many examples and detailed descriptions of template-based synthesis of nanomaterials including photonic crystals in some review papers (Martin, 1996 Hulteen, 1997 Huezko, 2000 Stein, 2001). 

Zhang, H. Zhang, X. Wu, T. Zhang, Z. Zheng, 1. Sun, H. Template-based synthesis and discontinuous hysteresis loops of cobalt nanotube arrays. J. Mater. Sci. 2013, 48, 7392-7398. 

Cao G, Liu D (2008) Template-based synthesis of nanorod, nanowire, and nanotube arrays. Adv Colloid Interface Sci 136 45-64... 

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