Simple and scalable preparation of robust and magnetic superhydrophobic papers by one-step spray-coating for efficient oil-water separation

We fabricated robust and magnetic superhydrophobic papers by a facile and scalable one-step spray-coating method for efficient oil-water separation. The coating was consisted of epoxy resin (EP), polydimethylsiloxane (PDMS), Fe3O4 and SiO2 nanoparticles. The surface characteristics of spray-coated papers were systematically investigated. The obtained EP@PDMS@Fe3O4@SiO2-coated paper possessed a water contact angle of 160o, fast magnetic response, excellent self-cleaning and anti-bacterial adhesion performance. The EP@PDMS@Fe3O4@-SiO2-coated paper achieved effective recovery of oil from water as a magnetic-controlled vessel and efficient gravity-driven separation of oil-water mixture and surfactant-stabilized oil-water emulsion as a filtering material. Moreover, EP@PDMS@Fe3O4@SiO2-coated paper exhibited excellent mechanical and chemical stability. Overall, we believe that the robust, magnetic and superhydrophobic papers prepared by a facilely scalable one-step spray-coating method in this study will have a promising application prospect in oily wastewater treatment and oil spill cleanup.