Synthesis and Properties of Bifunctional Fe $_{3}$ O $_{4}$ /Ag Nanoparticles

In this work, a facile synthesis of Fe₃O₄/Ag nanoparticles, with magnetic properties and electrical conductivity, was successfully developed, by reducing Ag(I) ions with D-Glucose, in the presence of a dispersion of superparamagnetic Fe₃O₄ nanoparticles, under ultrasound treatment. Poly(vinylpyrrolidone) (PVP) was used as protecting agent and Ag(I) were incorporated in different molar ratios with respect to Fe₃O₄ nanoparticles. The obtained particles were characterized by XRD studies, SEM and TEM observation, Energy Dispersive X-Ray Spectroscopy (EDS), DC magnetization and conductivity measurements. From TEM and SEM observation it was found that the PVP protection has shown to be partial, as the Fe₃O₄ nanoparticles have a lower diameter after the reduction treatment. Despite this, the particles retain the superparamagnetic behavior and the saturation magnetization decreases as the Ag content increases. From conductivity measurements, a minimum Ag(I)/Fe₃O₄ molar ratio = 1.75 was needed in order to observe electrical conductivity in the metallic regime.