Nano-casting technique to prepare polyaniline surface with biomimetic superhydrophobic structures for anticorrosion application

In this paper, polyaniline (PANI) surface with biomimetic superhydrophobic structures was first prepared by the nanocasting technique and applied in corrosion protection coatings. First of all, PANI was synthesized by conventionally oxidative polymerization of aniline with ammonium persulfate (APS) as oxidant in 1.0 M HCl aqueous solution. Subsequently, PANI with superhydrophobic surface (SH-PANI) of biomimetic natural leaf was fabricated, using PDMS as negative template, through casting onto cold rolled steel (CRS) electrode. Morphology of as-prepared PANI superhydrophobic surface was investigated by SEM. The contact angle of water droplet on sample surface can be increased from ∼90° of flat PANI surface (F-PANI) to ∼156° of SH-PANI. It should be noted that the SH-PANI was found to reveal better corrosion protection as compared to the F-PANI, base on a series of standard electrochemical corrosion measurements in saline conditions.

Graphical abstractConductive superhydrophobic surfaces were successfully prepared using the nanocasting method from a natural Xanthosoma sagittifolium leaves. It should be noted that the water contact angle of coating with bio-mimetic natural leaf surface was 156°, which was found to significantly higher than that of corresponding polymer with flat surface (i.e., CA = 90°). The significantly increase of contact angle indicated that this bio-mimetic morphology exhibited effectively water-repelling properties, implying that it provides excellent corrosion protection as advanced anticorrosive coating materials.Figure optionsDownload full-size imageDownload as PowerPoint slide