Efficient Dye Degradation via Catalytic Persulfate Activation using Iron Oxide-Manganese Oxide Core-Shell Particle Doped with Transition Metal Ions

Abstract

Organic-pollutants released into water bodies pose serious concerns because of its detrimental effects in aquatic biota, environment and economy. Water remediation using persulfate based advanced oxidation process is one of the emerging techniques. In this study, we have developed iron oxide-manganese oxide core–shell nanoparticles doped with transition metal ions for the efficient degradation of bromophenol blue dye, for the first time. Here, the transition metal ion doped MnOx shell enables efficient persulfate activation while the magnetic core facilitate in the effective recovery of used particles. The synthesized particles were characterized by X-ray powder diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and vibrating sample magnetometer. The presence of dopants is found to significantly change the ratio of Mn3+ to Mn4+, reactivity and mobility of lattice oxygen in doped samples. Silver ion doped MnOx showed the highest dye degradation efficiency of ~91% with 1.8 wt% nanoparticles, due to the enhanced reactivity and mobility of lattice oxygen activity of the core–shell nanoparticle in presence of Ag ions in persulfate activation. From the experimental results, the mechanism of activation of persulfate by nanoparticles is elucidated. Our findings provide a new platform for efficient water remediation using dual functional core shell magnetic nanoparticles.