Facile fabrication of recoverable and stable superhydrophobic polyaniline films

A superhydrophobic polyaniline (PANI) film was fabricated by using a facile one-step spraying method. The sprayed film showed stable superhydrophobic behavior at ambient environment for more than a month. However, after plasma treatment, the surface turned superhydrophilic and such wettability transition may be attributed to the change of surface composition since its rough surface microstructure remained the same as the pristine film without any treatment. The damaged film possessed a recoverable characteristic of superhydrophobicity when it was simply left in normal ambient conditions. After storage for 48 h, the low-energy-materials gradually transferred to the top surface and the superhydrophobicity of the damaged surface was healed. This recovery time can be shortened to only 10 min when the etched PANI film was wetted by deionized water.