NANOMAGNETITE MAGNETIZATION ON DEMAND VIA A NOVEL ELECTROSYNTHESIS ROUTE
2nd International Conference on MAGNETISM AND MAGNETIC MATERIALS
September 24- 26 , 2018 | Budapest , Hungary
Rafael A Prato M, V Van Vught, P Marin, S Eggermont J Fransaer and X Dominguez-Benetton
Flemish Institute for Technological Research, Belgium Instituto de Magnetismo Aplicado, Spain UCM, Spain KU Leuven, Belgium
Scientific Tracks Abstracts : Mater Sci Nanotechnol
A fast, environmentally friendly, room-temperature electrosynthesis route for magnetite nanocrystals is presented here. We use a gas diffusion electrode (GDE) to generate oxidants and hydroxide in-situ from air, enabling an oxidative electrosynthesis of particles from a single iron salt (FeCl2). Upon applying a potential of -350 mV vs. Ag/AgCl at the GDE, oxygen is reduced to reactive oxygen species (ROS) which triggers a controlled oxidation of Fe2+ to Fe3+, FeOOH and finally Fe3-xO4 are formed. The composition of nonstoichiometric magnetite can be finely controlled with the charge applied, which in turn determines the magnetic properties of the samples. In turn, the size of the nanocrystals can be tuned from 5 to 20 nm by changing the precursor concentration. The nanocrystals possess up to 85% of the bulk saturation magnetization of pure magnetite and minimal coercivity. Using air, NaCl and only FeCl2, a remarkable level of control over the size and composition of nanomagnetite is achieved at room-temperature and in a fast, environmentally friendly, and reproducible manner.
Rafael A Prato M has completed his BSc in Chemical Engineering at the University of California Santa Barbara, USA, and his MSc in Chemistry at the University of Oslo, Norway. He is currently pursuing a PhD in Materials Engineering jointly at the KU Leuven and the Flemish Institute for Technological Research (VITO), Belgium.
E-mail: [email protected]