Deposition of Silver Nanoparticles on Yttrium Manganese Oxide Powders.

ABSTRACTFollowing a novel silver nanoparticles synthesis pathway, pre-synthesized silver nanoparticles (4.4 nm of average diameter) were deposited on a substrate of yttrium manganese oxide. The method takes advantage of the spontaneous reduction of silver 2-ethylhexanoate in dimethyl sulfoxide (DMSO) at 50° C. Sodium citrate was used as capping agent. Silver nanoparticles dispersions mixed with yttrium manganite were kept for several days, at room temperature, in an Erlenmeyer flask wrapped in aluminum foil. Pure yttrium manganese oxide was prepared by solid state reaction of stoichiometric mixtures. The characterization of the samples mainly involved X-ray powder diffractometry and electron microscopy. Magnetic susceptibility was measured using a Quantum Design MPMS-5S SQUID magnetometer. Two samples were prepared: (I) YMnO3/Ag (1×10-3 M) and (II) YMnO3/Ag (5×10-2 M). The Ag nanoparticles deposition of (I) was confirmed by an increase in the surface area and a qualitative elemental analysis for silver. In (II) <10 nm silver nanoparticles were clearly appreciated by XRD and images of High Resolution Transmission Electron Microscopy. The measured value of magnetic susceptibility of (II) is slightly larger than pure YMnO3.