Structural Rearrangement of Bimetallic Alloy PdAu Nanoparticles Within Dendrimer Templates to Yield Core/Shell Configurations

Journal Article · Tue Jan 01 04:00:00 EST 2008 · Chemistry of Materials

DOI:https://doi.org/10.1021/cm0717817· OSTI ID:959653

Knecht, M; Weir, M; Frenkel, A; Crooks, R

Here we present evidence for an oxidation-driven structural conversion of quasi-alloy PdAu dendrimer-encapsulated nanoparticles (DENs) to a Au-core/Pd-shell configuration. The initial quasialloy was prepared by co-complexation of PdCl42- and AuCl4- within a sixth-generation, poly(amidoamine) dendrimer template followed by chemical reduction. Exposure to air resulted in selective reoxidation of the Pd atoms and subsequent re-reduction led to deposition of a Pd-rich shell on the surface of the remaining Au core. The core/shell nanoparticles were extracted as monolayer-protected clusters (MPCs) from within the dendrimer templates using dodecanethiol. The resulting materials were characterized by UV-vis spectroscopy, transmission electron microscopy, and extended X-ray absorption fine structure (EXAFS) spectroscopy.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 959653
• Report Number(s): BNL--82639-2009-JA
• Journal Information: Chemistry of Materials, Journal Name: Chemistry of Materials Vol. 20; ISSN CMATEX; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ABSORPTION
AIR
ALLOYS
ATOMS
CONFIGURATION
DEPOSITION
FINE STRUCTURE
SPECTROSCOPY
TRANSMISSION ELECTRON MICROSCOPY
national synchrotron light source