Nanoscale metals

Since nanoscale metal nanoparticles are applicable to a number of areas of technological importance, the nano-structured materials chemistry will occupy much attention of scientists. It is certain that controlling the primary structures of metal nanoparticles, that is, size, shape, crystal structure, composition, and phase-segregation manner is still most important, because these structures dominate the physical and chemical properties of metal nanoparticles. Now the liquid phase synthesis facilitates the precise control of the primary structures. 

Price, R.R., Dressick, W.J. and Singh, A. (2003) Fabrication of nanoscale metallic spirals using phospholipid microtubule organizational templates. Journal of the American Chemical Society, 125, 11259-11263. 

Emberly EG, Kirczenow G (2001) Models of electron transport through organic molecular monolayers self-assembled on nanoscale metallic contacts. Phys Rev B 64(23) 235412... 

Zhou C, Deshpande MR, Reed MA, Jones L, Tour JM (1997) Nanoscale metal/self-assem-bled monolayer/metal heterostructures. Appl Phys Lett 71 611-613... 

Mativetsky JM, Pace G, Elbing M, Rampi MA, Mayor M, Samori P (2008) Azobenzenes as light-controlled molecular electronic switches in nanoscale metal-molecule-metal junctions. J Am Chem Soc 130 9192-9193... 

Figure 12.10. Micrographs of devices fabricated using gravure printing technology. Left—shows the interdigitated transistor gate fabricated by an ink composed of nanoscale metallic particles. Right—Channel fabricated when using a silver-filled adhesive to print the transistor source and drain.

Nanoscale Metallics. Many of the metallization materials previously discussed, such as gold, can be developed into fine particles through either chemical reduction from a metal salt or from vaporization of the bulk metal.89 In fact, metals, such as gold, silver, palladium, and iron, can be harvested in elemental form from vegetation and grains that have been planted... 

C. Zhou, M. R. Deshpande, M. A. Reed, L. Jones II, J. M. Tour, Nanoscale Metal/Self-Assembled Monolayer/ Metal Heterostructures, Appl. Phys. Lett. 1997, 71, 611-613. 

Jiang, Y. Decker, S. Mohs, C. Klabunde, K.J. Catalytic solid state reactions on the surface of nanoscale metal oxide particles. J. Catal. 1998,180,24-35. 

Keywords Fluorescent marker Nanoclusters Nanodots Nanoscale metal Quantum dots... 

Highly reactive nanoscale metal particles (3 to 15 nm in diameter) are formed by reducing metal salts to metals by solvated elecrons or alkali metal anions that may also find use in organometallic synthesis [35]. 

Mercury-Sorption Characteristics of Nanoscale Metal Sulfides... 

M. Atteya, K.J. Klabunde, Nanoscale metal oxide particles as chemical reagents. Heats of adsorption of heteroatom containing organics on heat-treated magnesium oxide samples of varying surface areas. Chem. Mater. 3, 182-187 (1991)... 

Y.-X. Li et al., Adsorption and decomposition of organophosphorus compounds on nanoscale metal oxide particles. In situ GC-MS studies of pulsed microreactions over magnesium oxide. Chem. Mater. 4, 323-330 (1992)... 

Stark, J. V., Park, D. G., Lagadic, I. and Klabunde, K. J. Nanoscale metal oxide particles/ clusters as chemical reagents. Unique surface chemistry on magnesium oxide as shown by enhanced adsorption of acid gases (sulfur dioxide and carbon dioxide) and pressure dependence, Chem. Mater., 1996, 8, 1904-1912. 

FIGURE 3.1 Schematic of hypothetical closed-loop process for the production of CDC. Step 1 shows the transformation of carbide-producing metal oxides into metal carbides. Step 2 shows the conversion of metal carbides into CDC and metal chlorides. Step 3 shows the oxidation of metal chlorides into nanoscale metal oxides and chlorine. Also shown are high-resolution TEM (HRTEM) micrographs of SiC and SiC-CDC. 

Abstract This chapter is devoted to the electronic structure of nanoscale metallic magnets. 

Nanoscale metal oxides also exhibit biocidal properties due to their abrasive nature, alkaline surfaces, oxidizing power (when elemental halogens are preadsorbed), and the fact that their average particle charge (positive) attracts bacteria (which generally carry overall negative charge).11 In fact, nano-MgO is... 

Y. X. Li, and K. J. Klabunde, Nanoscale Metal-Oxide Particles As Chemical Reagents -Destructive Adsorption of A Chemical-Agent Simulant, Dimethyl Methylphosphonate, on Heat-Treated Magnesium-Oxide, Langmuir 7, 1388-1393 (1991). 

Stark JV, Park DG, Lagadic I, Klabunde KJ (1996) Nanoscale Metal Oxide Particles/Clusters as Chemical Reagents. Unique Surface Chemistry on Magnesium Oxide As Shown by Enhanced Adsorption of Acid Gases (Sulfur Dioxide and Carbon Dioxide) and Pressure Dependence, Chem Mater 8 1904-1912... 

Menon. M. Srivastava. D. Carbon nanotube "T junctions" Nanoscale metal-semiconductor-metal contact devices. Phys. Rev. Lett. 1997 79. 4453. 

The study of nanosized particles has its origin in colloid chemistry, which dates back to 1857 when Michael Faraday (1791-1867) set out to systematically investigate the optical properties of thin hhns of gold. Faraday prepared a suspension of ultra-small metaUic gold particles in water by chemically reducing an aqueous solution of gold chloride with phosphorus (Faraday, 1857). To this day, nanoscale metal particles are stiU produced by chemical reduction in aqueous solutions. 

Figure 13.15 Schematic representation of synthesis and surface modification of nanoparticles [54]. (Reproduced with permission from W.J. Rieter et al., Surface modification and functionalization of nanoscale metal-organic frameworks for controlled release and luminescence sensing, Journal of the American Chemical Society, 129, 9852-9853, 2007. 2007 American Chemical Society.)...

The nanometer-sized single molecule can be regarded as a local probe of electromagnetic and electrostatic interactions extremely close to the molecule, because the probability of excitation depends upon the local optical field as described above. In addition, under certain conditions, the molecule s emission can be influenced by the proximity of nanoscale metallic or dielectric structures. 

On the experimental side, we expect NMR to remain an important tool in the analysis of the nanoscale metallic materials widely used in heterogeneous and electrocatalysis. Its unique molecular/electronic information will complement that from other techniques such as IR, x-ray, or STM, etc. This is particularly true in the field of interfacial electrochemistry, where many electron-based spectroscopies are technically inapplicable. 

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