Facile fabrication of PS/Fe3O4@PANi nanocomposite particles and their application for the effective removal of Cu2+

Abstract

This work presents a simple and straightforward approach to fabricating multifunctional nanocomposite particles which possess a core of a polystyrene (PS) particle, a transition layer of magnetic Fe₃O₄ nanoparticles (NPs), and an outer shell of adsorbable polyaniline (PANi). In detail, the positively charged Fe₃O₄ NPs synthesized via the chemical co-precipitation method are directly loaded onto the negatively charged surfaces of the PS particles obtained by emulsifier-free emulsion polymerization through electrostatic self-assembly; subsequently, the coating of the resultant PS/Fe₃O₄ nanocomposite particles with PANi was successfully achieved by virtue of the “swelling–diffusion–interfacial-polymerization method” (SDIPM). Furthermore, the adsorption of Cu²⁺ by PS/Fe₃O₄@PANi nanocomposite particles was investigated by changing the initial pH value, adsorption time, and initial concentration of the adsorbate. The adsorption data in our work follow a pseudo-second-order kinetics model and fit the Langmuir isotherm model. The PS/Fe₃O₄@PANi nanocomposite particles show that the maximum adsorption capacity is up to 181.5 mg g⁻¹ at pH 5. More importantly, these nanocomposite particles can be easily recovered using an external magnetic field owing to the presence of Fe₃O₄ NPs, and the regenerated nanocomposite particles can be repeatedly used for eight cycles without significant loss of their adsorption capacity.