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

Abstract 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° with different oils in air. The modified sponge exhibited superoleophobicity in water, and the contact angle of oil could reach more than 150°. 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.