Effect of the anodic potential applied in the electrochemical synthesis of magnetite-chitosan nanoparticles on their physicochemical characteristics

Magnetite nanoparticles (MNp) have demonstrated applications in different areas due to their properties, such as magnetism, adsorption, biocompatibility, low toxicity, and antimicrobial activity, which mainly depend on the synthesis methods. However, current methods have some drawbacks, such as the presence of maghemite, the oxidation process and the poor control of particle size and distribution. Therefore, the synthesis by electrochemical methods of MNp is proposed, applying three different anodic potentials (0.8, 0.3 and − 0.2 V vs. Hg|Hg 2 Cl 2 ) and its surface modification with chitosan (CS). In addition, in order to identify the effect of the anodic potentials in obtaining MNp and MNp modified with chitosan (MNp-CS), the characterization of these magnetic materials by physicochemical methods was carried out, through which it was demonstrated the obtaining of MNp and MNp-CS by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV–vis spectrophptometry, in addition, it was observed that the MNp-CS synthesized at the anodic potentials of 0. 8 V and 0.3 V vs. Hg|Hg 2 Cl 2 show higher colloidal stability, pore volume, specific surface area and magnetic properties, which could contribute to their efficiency to adsorb metal ions, dyes, and microorganisms. • Quasi-spherical nanoparticles were obtained using asymmetric potential pulses. • The particles showed crystalline phases of magnetite and maghemite. • The sizes of the nanoparticles suggest that they are superparamagnetic. • Magnetic nanoparticles demonstrated high colloidal stability. • The surface area increases with more positive values of the anodic potential.