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Position:Home > News > Technical Data > Solvent and Simple Ion-Stabilized Metal Nanoclusters
Solvent and Simple Ion-Stabilized Metal Nanoclusters
Source:    Published:2011/6/9 16:06:38

   Solvent and Simple Ion-Stabilized Metal Nanoclusters: Chemical Synthesis and Application Yuan Wang and Xiaodong Wang Beijing National Laboratory for Molecular Sciences, State Key Laboratory.for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular En6tineering, Peking University, Bezjing, China Introductiori To prepare stable metal nanoclusters with small particle size and narrow size distribution in colloidal solutions, protective agents of polymers, such as poly(N-vinyl-2pyrrolidone) (PVP) and polyvinylalcohol (PVA), coordination ligands such as PPh3 and mercaptans, or surfactants are usually required. The protective agents can adjust the aggregation process of metal atoms to form metal nanoclusters with narrow size distribution, and provide

  

   potential barriers to prevent the metal nanoparticles from aggregating. However, the interaction between the metal colloidal particles and the protective agents may affect or alter the physical and chemical properties of the nanoscopic metal particles, thereby restricting the applications of protected metal nanoclusters in some aspects. For the purpose of studying the intrinsic properties of metal nanoparticles and employing the metal nanoclusters as

   nanosized building blocks for assembling some important functional systems conveniently, "unprotected" metal nanoclusters with sufficient stability are desirable.

  

   The so-called "unprotected" metal nanoclusters are prepared in the absence of usual protective agents; however, they are not truly bare but stabilized by solvents and simple ions adsorbed on them, or by both. Successful examples for preparing such metal colloidal solutions are still limited. Klabunde and co-workers developed a solvated metal atom dispersion technique (SMAD), which involves vaporization of a metal under vacuum and codeposition of the metal atoms with the vapors of a solvent on the walls of a reactor cooled t0 77 K, followed by warming the frozen matrix to produce metal nanoclusters stabilized by solvent and negative charge [1,2]. Stable Pd colloids with average diameters of 6-8 nm in acetone or propanol could be prepared using the SMAD technique The syntheses of Au nanoparticles and their immobilization [4] or surface modification with mercaptan [5]

  

  

CAS NO.87693-81-0
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