Multifunctional magnetic oleic acid-coated MnFe2O4/polystyrene Janus particles for water treatment

Abstract

In this work, we have demonstrated the multifunctional magnetic oleic acid-coated MnFe₂O₄/polystyrene (MnFe₂O₄@OA/PS) Janus particles for eliminating multiple contaminants from water. The MnFe₂O₄@OA/PS Janus particles are simply prepared on a large scale by utilizing the phase separation of oleic acid coated MnFe₂O₄ nanoparticles (MnFe₂O₄@OA NPs) and polystyrene (PS) in evaporating n-hexane/chloroform droplets. The as-prepared MnFe₂O₄@OA/PS Janus particles can effectively integrate three intriguing properties, including the instinctive surface amphipathicity, excellent magnetic properties and high catalytic activity. Hence, they not only can act as particle surfactants to encapsulate and magnetically separate oil droplets from water, but also can efficiently degrade organic dyes in water by utilizing hydroxyl radicals generated from the active Fenton reaction between MnFe₂O₄ and H₂O₂. The integrated removal of oil and organic dyes by using the multifunctional MnFe₂O₄@OA/PS Janus particles exhibits obvious advantages including simple procedures, low cost and easy operation. The MnFe₂O₄@OA/PS Janus particles developed in this work may inspire novel strategies for the practical applications of Janus particles in the water treatment for multiple-contaminant removal due to their versatile components as well as the facile, large-scale fabrication approach.