Superhydrophilic and oleophobic sponges prepared based on Mussel-Inspired chemistry for efficient oil-water separation

Superhydrophilic/oleophobic materials are considered to be the best materials for achieving oil-water separation, but their preparation is difficult and the existing methods are not universal. In this paper, a two-step modification strategy was used to prepare superhydrophilic/oleophobic sponges by adjusting the polar and nonpolar components of the materials using mussel-inspired chemistry. While remaining superhydrophilic, the modified sponge surface has a maximum contact angle of 135 degrees with different oils in air. The modified sponge exhibited superoleophobicity in water, and the contact angle of oil could reach more than 150 degrees. In addition, the modified sponges were also reusable, chemically stable, and mechanically durable. Its oil-water separation flux was up to 24900 Lm-2 h-1 bar-1, and the separation efficiency was above 97 %. We believe that this method will provide an environmentally friendly and efficient way to prepare the superhydrophilic/oleophobic materials. A two-step modification strategy was used to prepare superhydrophilic/oleophobic (in air) sponges by adjusting the polar and nonpolar components of the materials using mussel-inspired chemistry.image