Extraction of monodisperse palladium nanoparticles from dendrimer templates.
We describe a strategy for extracting nearly size-monodisperse, 1.7-nm-diameter Pd nanoparticles from within dendrimer hosts. The approach involves two steps. First, an aqueous solution of dendrimer-encapsulated Pd nanoparticles is prepared, followed by the addition of a toluene solution containing an n-alkanethiol. When the two-phase system is stirred, n-alkanethiols presumably self-assemble onto the surface of the Pd nanoparticles, extract them from the dendrimer, and transport them to toluene phase. UV-vis spectroscopy indicates that the Pd nanoparticles, in the form of monolayer-protected clusters, are transported into the toluene phase. FT-IR spectroscopy shows that the dendrimers remain in the aqueous phase. High-resolution transmission electron microscopy shows that the average size and size distribution of the particles do not change during the extraction process.
Garcia-Martinez
Joaquin C
JC
Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
Scott
Robert W J
RW
Crooks
Richard M
RM