Facile preparation of durably magnetic superhydrophobic sponge and its application in oil-water separation

摘要

Herein, a stable three-dimensional composite sponge with magnetic and superhydrophobic was prepared via a two-step process including self-polymerization of dopamine (DA) and anchoring of Fe3O4 particles assisted by polydopamine (PDA) and polydimethylsiloxane (PDMS). The modified sponge exhibited high adsorption capacity (52.39-91.52 g/g) for diverse oils and organic solvents, which can be easily recovered in oil-water mixture under magnetism. The excellent properties were attributed to the synergistic effect of micro-nano structures and low surface energy, which were derived from the coatings of PDA and Fe3O4 and hydrophobic methyl groups of PDMS, respectively. When the temperature of PDA coating was 40 degrees C, the water contact angle (WCA) of the prepared superhydrophobic sponge reached 152.74 +/- 0.2 degrees. More importantly, the present adsorbents possessed robust chemical, mechanical, and temperature stability at a harsh environmental and good reusability for oil-water separation after 12 cycles of repeated adsorption, which enable to deal with oil leakage under harsh conditions still maintaining the excellent performance.