Fig. 11

Schematic illustration of underwater oil wettability on the obtained surfaces: for surfaces prepared with XOH ≤ 0.2, the surfaces are mainly covered by the hydrophobic and oleophilic methyl groups ; thus the oil droplet can enter into the microstructures, and the surface would show underwater superoleophilicity (a). For the surface prepared with XOH ≥ 0.6, the presence of many hydroxyl groups increases the hydrophilicity of the surface, and water can enter into the microstructures; the oil droplet would reside in the composite Cassie state, and the surface would show superoleophobicity (b) [83]