MWCNTs decorated Mn0.8Zn0.2Fe2O4: Synthesis, characterization and compositional effect on the structural and magnetic properties

Abstract

Abstract In the present study, Mn0.8Zn0.2Fe2O4 nanoparticles, synthesized from spent Zn–C batteries extract, were successfully used for decoration of multi-walled carbon nanotubes (MWCNTs). This MWCNTs/Mn0.8Zn0.2Fe2O4 magnetic nano-composites were prepared by the addition of MWCNTs during the preparation of the entire ferrite using sucrose combustion method. The effect of MWCNTs content (0–70%) on the structural, morphological and magnetic properties of entire ferrite was investigated and discussed. The results showed that high purity Mn0.8Zn0.2Fe2O4 nano-crystallites were completely decorated on the sidewalls of the MWCNTs up to 30% content and the decoration behavior, shape and density are dependent on the composition. The saturation magnetization was observed to decrease with increasing MWCNTs content while coercivity showed a particle size dependent behavior. The composition with 70% MWCNTs was examined as adsorbent for methylene blue dye (MB) from aqueous media based on its relatively high surface area and the capability of removing the nano-composite after adsorption process using normal magnet. The nano-composite showed a very high adsorption capacity and the kinetic as well as the thermodynamics of adsorption/removal process were investigated and discussed. Repeated testing showed the applicability of the nano-composite for the removal of MB from aqueous solution frequently with acceptable efficiencies.