Ag nanoparticles embedded in a magnetic composite for magnetic separation applications

Abstract

This work is focused on the preparation of a multifunctional compound consisting of silver nanoparticles (AgNPs) embedded in a matrix of amorphous carbon previously loaded with Fe3C magnetic particles. The objective is to use the antibacterial properties of the AgNPs for environmental purposes, in such a way that the AgNPs can be recovered by physical means (magnetic separation). The synthesis method was direct from ferrocene, silver nitrate and polyethylene glycol placed in a reaction tube and pyrolyzed by a plasma produced under vacuum conditions. For this, a conventional microwave oven was used. The compound obtained is a black powder, with similar consistency to graphite, but it responds strongly to the application of magnetic fields. The material was thoroughly characterized by X-ray photoelectron, energy-dispersive X-ray spectroscopies; transmission and scanning electron microscopies; X-ray diffraction, as well magnetic characterizations using a vibrating sample magnetometer. The material showed a homogeneous dispersion of metal particles in the carbon matrix. We conclude that the combination of magnetic and antibacterial properties makes this material interesting for several applications through the use of magnetic separation protocols.