Reaction Mechanisms of the Electrosynthesis of Magnetite Nanoparticles Studied by Electrochemical Impedance Spectroscopy

Abstract

This work presents a mechanistic study of the electrochemical synthesis of magnetite nanoparticles (NPs) based on the analysis of the electrochemical impedance spectroscopy (EIS) technique. After a discussion of the mechanisms reported in the literature, three models are devised and a prediction of their EIS spectra is presented. The approach consisted of the simulation of EIS spectra as a tool for assessing model validity, as EIS allows to characterize the relaxation of adsorbed intermediates. The comparison between the simulated impedance spectra and the experimental results shows that the mechanisms proposed to date do not explain all of the experimental results. Thus, a new model is proposed, in which up to three adsorbed intermediate species are involved. This model accounts for the number of loops found in experimental impedance data. The closest approximation of the features found in the experimental spectra by this proposed model suggests a better representation of the reaction mechanism within the evaluated potential range.

Ni(1−x)Pdx Alloyed Nanostructures for Electrocatalytic Conversion of Furfural into Fuels

“…The lower charge transfer resistance indicates more facile electron transfer between the interface of the active electrode and the electrolyte solution in the presence of furfural. Meanwhile, the highest double-layer capacitance of value 0.00050499 was obtained for the Ni0.75Pd0.25 electrodes, which proposes increased charge density around the electrode [35]. Therefore, a high catalytic activity for furfural hydrogenation reaction is expected using Ni0.75Pd0.25 and Ni0.80Pd0.20 electrodes.…”