Fe3O4 embedded ZnO nanocomposites for the removal of toxic metal ions, organic dyes and bacterial pathogens

Abstract

We report a facile soft-chemical approach for the fabrication of Fe₃O₄ embedded ZnO magnetic semiconductor nanocomposites (Fe₃O₄–ZnO MSN), and investigate and compare their efficacy for the detoxification of water with respect to their individual counterparts (Fe₃O₄ and ZnO). The formation of Fe₃O₄–ZnO MSN was evident from the detailed structural analyses by XRD, TEM and magnetic measurements. It has been observed that these nanocomposites have a strong tendency for the simultaneous removal of Ni²⁺, Cd²⁺, Co²⁺, Cu²⁺, Pb²⁺, Hg²⁺ and As³⁺ from waste-water due to their porous network structure, surface polarity and high surface area. These nanocomposites also show a good photocatalytic activity for the degradation of organic dyes under UV irradiation, and are found to be efficient in the easy and rapid capturing of bacterial pathogen. It has been observed that the efficiency of capturing bacteria is strongly dependent on the concentration of nanoadsorbents and their inoculation time. It is investigated that these nanoadsorbents can be used as highly efficient separable and reusable materials for the simultaneous removal of toxic metal ions, organic dyes and bacterial pathogen.