Copper core-shell

Bimetallic nanoparticles, either as alloys or as core-shell structures, exhibit unique electronic, optical and catalytic properties compared to pure metallic nanopartides [24]. Cu-Ag alloy nanoparticles were obtained through the simultaneous reduction of copper and silver ions again in aqueous starch matrix. The optical properties of these alloy nanopartides vary with their composition, which is seen from the digital photographs in Fig. 8. The formation of alloy was confirmed by single SP maxima which varied depending on the composition of the alloy. 

We synthesized uniform CU2O coated Cu nanoparticles from the thermal decomposition of copper acetylacetonate, followed by air oxidation. We successfully used these nanoparticles for the catalysts for Ullmann type amination coupling reactions of aryl chlorides. We synthesized core/shell-like Ni/Pd bimetallic nanoparticles from the consecutive thermal decomposition of metal-surfactant complexes. The nanoparticle catalyst was atom-economically applied for various Sonogashira coupling reactions. 

Similarly, Pd, Ag, and Pd-Ag nanoclusters on alumina have been prepared by the polyol method [230]. Dend-rimer encapsulated metal nanoclusters can be obtained by the thermal degradation of the organic dendrimers [368]. If salts of different metals are reduced one after the other in the presence of a support, core-shell type metallic particles are produced. In this case the presence of the support is vital for the success of the preparation. For example, the stepwise reduction of Cu and Pt salts in the presence of a conductive carbon support (Vulcan XC 72) generates copper nanoparticles (6-8 nm) that are coated with smaller particles of Pt (1-2 nm). This system has been found to be a powerful electrocatalyst which exhibits improved CO tolerance combined with high electrocatalytic efficiency. For details see Section 3.7 [53,369]. 

Copper surface, 137 Co-precipitation, 440 method, 312, 388 Core shell structure, 411, 415 Crookes, Sir William, 39 Cronstedt, Axel Frederik, 5 Crystal field symmetry, 371 Crystallographic relationships, 265 ErCuPbSj, 265 ErCuPbSej, 265 Er5CuPb3Sen, 266 Er2EuS4, 267 Er2PbS4, 267 LaCuPbSs, 265 La2S3, 265... 

The experimentally observable fluorescence decay rate is a final product of QD size, surface, emission wavelength, electron hole overlap, as well as time varying extrinsic factors such as local chemical potential.In general, these factors vary not just from sample to sample but even for a single nanocrystal over time. At an ensemble level this generally leads to a multiexponential PL deeay in most cases, though a few notable exceptions (PbSe QDs, " Copper Indium Sulphide Core/shells " and certain alloy QDs) do exist. 

The well-aligned array of the core-shell nanostructure was formed using copper sulfide nanorods coated with PPy nanolayers [246]. PPy was homogeneously deposited on a copper sulfide nanorod via in-situ polymerization at the interfacial layer between chloroform and water. The uniform PPy coating was achieved by two factors of confinement (1) it was vertically confined at the interfacial layer of chloroform and water (2) it was horizontally confined in the interrod spaces of the nanorod arrays. The growth of PPy film was timable by adjusting polymerization time, monomer concentration, and monomer-to-oxidant weight ratio. 

Li L, Pandey A, Werder DJ, Khanal BP, Pietryga JM, Klimov VI (2011) Efficient synthesis of highly luminescent copper indium sulfide-based Core/Shell nanocrystals with surprisingly... 

Sisk C N, Hope-Weeks J (2008) Copper(II) aerogels via 1,2-epoxide gelation. J Mater Chem 18 2607-2610 Leventis N, Vassilaras P, Fabrizio E F, Dass A (2007) Polymer nanoencapsulated rare earth aerogels chemically complex but stoichiometrically similar core-shell superstructures with skeletal properties of pure... 

In 2007, Lee and coworkers reported the synthesis of a core-shell type polymer-supported (NHC)-Pd catalyst 28 (Figure 4.8), which was used to catalyze copper-free Sonogashira reactions under ambient atmosphere [39]. The... 

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