Controllable superhydrophobic and lipophobic properties of ordered pore indium oxide array films

Using the polystyrene (PS) colloidal monolayers as templates, ordered indium oxide pore array films with different morphologies were prepared by sol-dipping method. These porous films took on hydrophilicity, however, after chemical modification, such pore array films displayed both superhydrophobicity and lipophobicity due to rough surface and low surface free energy materials on their surfaces. Interestingly, with increase of the pore size in the films, the superhydrophobicity could be controlled and was gradually enhanced due to the corresponding increase of roughness caused by nanogaps produced by the thermal stress in the annealing process with increase of film thickness.