Synthesis of Cu@ZnO Core−Shell Nanocomposite through Digestive Ripening of Cu and Zn Nanoparticles

Abstract

The synthesis of colloids of copper and zinc nanoparticles by solvated metal atom dispersion (SMAD) is described. The as-prepared colloids with a large size distribution of the particles are transformed into colloidal nanoparticles of a narrow size distribution by the digestive ripening process which involves refluxing the colloid at or near the boiling point of the solvent in the presence of a passivating ligand. The copper nanoparticles of 2.1 ( 0.3 nm and zinc nanoparticles of 3.9 ( 0.3 nm diameters have thus been obtained. Digestive ripening of the as-prepared copper and zinc colloids together in the presence of a passivating agent gave Cu@ZnO core-shell nanoparticles, with an average diameter of 3.0 ( 0.7 nm. Particles synthesized in this manner were characterized by UV-visible spectroscopy, high-resolution electron microscopy, energyfiltered electron microscopy, and powder X-ray diffraction methods which confirm the core-shell structure.

Stabilizer‐Free Metal Nanoparticles and Metal–Metal Oxide Nanocomposites with Long‐Term Stability Prepared by Physical Vapor Deposition into Ionic Liquids

“…The solvent was evaporated to give a low-viscosity colorless liquid. Yield: 92.8 %, 54.48 g. Preparation of Cu and Au nanoparticles: Typical SMAD equipment (TVP 800, Torrovap, Canada) as described in detail in reference [37], was used to prepare the coinage-metal colloids. In a typical experiment, the ionic liquid (40 mL) was placed in the glass bulb of the reactor and of the desired metal (80 mg) was placed in a tungsten crucible for evaporation.…”

“…[36] Recently, the synthesis of Cu@ZnO core-shell nanocomposites by solvated metal atom dispersion (SMAD) has been reported. [37] The technique, originally developed by Klabunde and co-workers, [38] consists of cocondensation of substrate vapors together with a cosolvent or stabilizing agent, in this case 2-butanone, under high vacuum onto a target that is maintained at liquid nitrogen temperature. Upon thawing, the desired compound forms.…”

Synthesis and investigation of novel ZnO–CuO core-shell nanospheres

“…Coreshell type hybrid structure, as a typical structure of quantum dots system, has important theoretical research value and exhibits novel properties [6][7][8][9]. Thus it is promising to use the core-shell structure to change some properties, such as surface modification through shell building.…”

“…Thus it is promising to use the core-shell structure to change some properties, such as surface modification through shell building. Numerous core-shell structures have been explored in recent years, including ZnO-ZnS core-shell nanorods [7], ZnS-MgO core-shell structure [8], and Cu-ZnO core-shell nanocomposite [9].…”

Stabilisatorfreie langzeitstabile Metall‐Nanopartikel und Metall‐ Metalloxid‐Nanokomposite durch physikalische Gasphasenabscheidung

“…[36] Es wurde kürzlich über die Synthese von Cu@ZnO-Kern-Schale-Nanokompositen mit der SMADTechnik (solvated metal atom dispersion) berichtet. [37] Bei dieser Technik, die im Ursprung von Klabunde und Mitar-beitern entwickelt wurde, [38] Um die optischen Eigenschaften zu untersuchen, wurden UV/Vis-Spektren aufgenommen (Abbildung 1 e). Das Absorptionsmaximum bei 576 nm wird durch die Oberflächen-plasmonenresonanz (SPR) der Kupfer-Nanopartikel hervorgerufen.…”