| Abstract
| - Using PAMAM dendrimers as nanoparticle templates, a synthetic route to prepare 3 nm magnetic NiAunanoparticles was developed. Aqueous solutions of hydroxyl-terminated generation 5 PAMAM dendrimersin 25 mM NaClO4 were shown to bind aqueous NiII. Coreduction of NiII and AuIII salts yielded bimetallicdendrimer stabilized nanoparticles, which were extracted into toluene with decanethiol. Characterization ofthe resulting monolayer protected clusters (MPCs) with transmission electron microscopy and UV−visible,atomic absorption, and X-ray photoelectron spectroscopies suggested that the MPCs had substantial surfaceenrichment in Au. Superconducting quantum interference device (SQUID) measurements at 5 K show thebimetallic MPCs to have low coercivity and saturation magnetization relative to bulk Ni. Solution nuclearmagnetic resonance (NMR) studies using the Evans method showed the bimetallic nanoparticles retain magneticproperties at ambient temperatures.
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