Noble metal nanoparticles synthesis

Reddy KR, Sin BC, R) KS et al (2009) Conducting pol3nner functionalized multi-walled carbon nanotubes with noble metal nanoparticles synthesis, morphological characteristics and electrical properties. S5mth Met 159 595-603... 

Noble metal nanoparticles dispersed in insulating matrices have attracted the interest of many researchers fromboth applied and theoretical points of view [34]. The incorporation of metallic nanoparticles into easily processable polymer matrices offers a pathway for better exploitation of their characteristic optical, electronic and catalytic properties. On the other hand, the host polymers can influence the growth and spatial arrangement of the nanoparticles during the in situ synthesis, which makes them convenient templates for the preparation of nanoparticles of different morphologies. Furthermore, by selecting the polymer with certain favorable properties such as biocompatibiHty [35], conductivity [36] or photoluminescence [37], it is possible to obtain the nanocomposite materials for various technological purposes. 

Facile in situ synthesis of noble metal nanoparticles in porous cellulose fibers. Chemistry of Materials, 15, 4401 1406. 

Similarly, Kou et al. published the synthesis of PVP-stabilized noble-metal nanoparticles in ionic liquids BMI PF6 at room temperature [76]. The metal nanoparticles (Pt, Pd, Rh) were produced by reduction of the corresponding metal halide salts in the presence of PVP into a refluxing ethanol-water solution. After evaporation to dryness the residue was redissolved in methanol and the solution added to the ionic liquid. The methanol was then removed by evaporation to give the ionic liquid-immobilized nanoparticles. These nanoparticles were very stable. TEM ob-... 

A new class of heterogeneous catalyst has emerged from the incorporation of mono- and bimetallic nanocolloids in the mesopores of MCM-41 or via the entrapment of pro-prepared colloidal metal in sol-gel materials [170-172], Noble metal nanoparticles containing Mex-MCM-41 were synthesized using surfactant stabilized palladium, iridium, and rhodium nanoparticles in the synthesis gel. The materials were characterized by a number of physical methods, showed that the nanoparticles were present inside the pores of MCM-41. They were found to be active catalysts in the hydrogenation of cyclic olefins such as cyclohexene, cyclooctene, cyclododecene, and... 

Khomutov GB, Gubin SP (2002) Interfacial synthesis of noble metal nanoparticles. Mater Sci Eng C 22 141-146... 

Hydrocarbonyl compounds, lanthanide complexes, 4, 4 ( -Hydrocarbyl)bis(zirconocene), preparation, 4, 906 Hydrocarbyl-bridged cyclopentadienyl-amido complexes, with Zr(IV), 4, 864 Hydrocarbyl complexes bis-Cp Ti hydrocarbyls reactions, 4, 551 structure and properties, 4, 551 synthesis, 4, 542 cobalt with rf-ligands, 7, 51 cobalt with rf-ligands, 7, 56 cobalt with ]4-ligands, 7, 59 cobalt with rf-ligands, 7, 71 heteroleptic types, 4, 192 homoleptic types, 4, 192 into magnetic metal nanoparticles via ligand stabilization, 12, 87 via polymer stabilization, 12, 87 into noble metal nanoparticles... 

The deposition-precipitation method as proposed by Haruta et al. (1993) provides another way to synthesize composite materials with noble metal nanoparticles over metal-oxide supports. The synthesis of gold and platinum nanoparticles supported on various metal oxide substrates (such as Ti02, ZnO, Ce02, C03O4 and Fe203) (Bamwenda, Tsubota, Nakamura and Haruta 1995 Boccuzzi, Chiorino, Tsubota and Haruta 1996 Centeno, Carrizosa and Odriozola 2003 Moon, Lee, Park and Hong 2004 Zanella, Delannoy and Louis 2005 Li, Comotti and Schuth 2006) has been continually reported in the past one and a half decades. 

Figure 6.16. Comparative energy levels for magic number noble metal nanoclusters relative to bulk metal. Also shown are the perfect fee arrays of the nanoclusters, in which more than 75% of the atoms are located on the surface. Adapted with permission from Finke, R. G. in Metal Nanoparticles Synthesis, Characterization, and Applications Feldheim, D. L. Foss, C. A. eds., Dekker New York, 2002. Copyright 2002 Taylor Francis.

Similar methods for the preparation of noble metal nanoparticles on carbon materials are being used extensively for the synthesis of electrocatalysts. 

The asymmetric hydrogenation of prochiral ketones is often an important step in the industrial synthesis of fine and pharmaceutical products. Several noble metal nanoparticles have been investigated for asymmetric catalysis of prochiral substrates but platinum colloids have been the most widely studied and relevant enantiomeric excesses have been reported (>95%). Nevertheless, the enantioselec-tive hydrogenation of ethyl pyruvate catalyzed by PVP-stabilized rhodium nanocluster modified by cinchonidine and quinine was reported by Li and coworkers (Scheme 11.7) [68]. 

Pringle, J. M., Winther-Jensen, 0., Lynam, C., Wallace, G. G., Forsyth, M., and MacFarlane, D. R. (2008). One-step synthesis of conducting polymer-noble metal nanoparticle composites using an ionic liquid. Adv. Fund Mater., 18, pp. 2031-2040. 

A. Manna, T. Imae, K. Aoi, M. Okada, T. Yogo, Synthesis of Dendrimer-Passivated Noble Metal Nanoparticles in a Polar Medium Comparison of Size between Silver and Gold Particles, Chemistry of Materials 13, 1674, 2001. 

Although gold colloids were known and studied very early [3.2], the synthesis technique has been much studied and greatly improved during the past few decades. The two-phase approach permits the fabrication of thiol-covered noble-metal nanoparticles [3.141]. The thiol layer prevents coalescence of the metal particles, thus stabilizing the colloid and preserving the size distribution. Motivated by the self-ordering properties of layers of nanoparticles with a narrow size distribution. 

Synthesis and characterization of noble metal nanoparticles/kaolinite composites... 

H. S. Qian, M. Antonietti, and S. H. Yu, Hybrid Golden Fleece Unique approaches for synthesis of uniform carbon nanofibres and silica nanotubes embedded/confined with high population of noble metal nanoparticles and their catalytic performance. Adv. Eunct. Mater, 17, 637-643, 2007. 

Amendola V, Meneghetti M. Laser ablation synthesis in solution and size manipulation of noble metal nanoparticles. Physical Chemistry Chemical Physics 2009 11 3805-21. http //dx.doi.org/10.1039/b900654k. 

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