Facile Fabrication of Superhydrophobic Sponge with Selective Absorption and Collection of Oil from Water

A simple vapor-phase deposition process has been developed to fabricate a superhydrophobic and superoleophilic sponge using ordinary commercial polyurethane sponges. The simultaneous properties of superhydrophobicity and superoleophilicity enable the sponge to float on the water surface and selectively absorb oil from water. Its uptake capacities of different oils (motor oil, lubricating oil, pump oil, silicone oil, and soybean oil) in the oil–water mixtures were all above 20 g/g. The absorbed oil could be collected by squeezing the sponge, and the recovered sponge could be reused in oil–water separation for many cycles while still maintaining a high capacity. This is helpful for realizing the proper disposal of the oil and avoiding secondary pollution. A similar experiment was performed using the as-prepared sponge to remove petroleum from contaminated water. The results suggest that our material might find practical applications in the cleanup of oil spills and the removal of organic pollutants from water surfaces.