Proposal and Verification of a Novel Superhydrophobic-Conductive Anti-Corrosion Polyaniline-Silica Coating

Abstract There has been a growing interest in stainless steel (SS) corrosion due to massive economic losses. Current efforts are mainly devoted to forming Cr2O3 film or organic coatings on SS surfaces. However, the relevant chromate is a carcinogen and the traditional organic coatings are inefficient for electrochemical corrosion. Here, we prepared a novel superhydrophobic-conductive anti-corrosion polyaniline-silica (PANI-SiO2) coating, the internal conductive polyaniline layer effectively reduces electrochemical corrosion, the external superhydrophobic silica layer obviously reduces chemical corrosion. Compared with 304 stainless steel (304SS), the corrosion potential (Ecorr) of the PANI-SiO2 increases to more than 331 mV (SCE), the corrosion current (Icorr) is reduced by more than one order of magnitude, and the anti-corrosion efficiency reaches 97.51%. Meanwhile, the PANI-SiO2 coating has good long-term anti-corrosion performance for 304SS.