An Insight into the Magnetic Field Effects on Spin-Dependent Electrochemical Redox Reactions and Electroreduction Kinetic Parameters by Using a Magneto-Plasmonic Ag@Fe3O4 Sensing Nanoplatform

Abstract

In this study, the metallic-Ag@ferromagnetic-Fe3O4 nanoparticles has been used as a promising spintronics material to gain deeper insights into spintronics-related electrochemical reactions under the influence of an applied external magnetic field (MF) including spin polarization, spin transport, and spin selectivity. Ferrocyanide/ferricyanide ([Fe(CN)6]3‒/4‒), paracetamol (PCM), and chloramphenicol (CAP) were chosen as the suitable reactants for one-electron transfer reversible redox reaction, two-electron transfer quasireversible redox reaction, and four-electron transfer irreversible reaction at Ag@Fe3O4 modified electrodes, respectively. By using an external MF-assisted electrochemical platform and magneto-plasmonic Ag@Fe3O4 electrode to trigger spin polarizing, spin transporting, and spin selectivity effects in electrode reactions, the selective enhancement of the electro-reduction reaction in comparison with electro-oxidation reaction has been elucidated. The obtained experimental data along with calculated electrochemical kinetic parameters indicate that an applied external MF affects the electrochemical kinetics (electron transfer kinetics, electrocatalytic activity, and adsorption/diffusion capacity) of the one-, two-, and four-electron transfer processes in different ways. Considering the pronounced effects of magnetic field on overall electrochemical performance and intrinsic advantages of spintronics enhanced the electro-reduction reaction, these developed techniques could provide innovative strategies for the development of novel spin-dependent electrochemical sensing approaches.