Inhibition of Biocorrosion of Aluminum 2024 Aeronautical Alloy by Conductive Ladder Polymer Poly(o-phenylenediamine)

The present study examines the role of conductive polymer poly(o-phenylenediamine) in corrosion inhibition and its antibacterial activity against bacterial biofilm (Bacillus cereus ACE4) on aluminum 2024 aeronautical alloy (AA 2024). Poly(o-phenylenediamine) (PoPD) was successfully electropolymerized by cyclic voltammetery on AA 2024 using sulfuric acid solution containing o-phenylenediamine monomer. The PoPD coating vias characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy energy-dispersive X-ray (SEM7-EDAX) spectroscopy analysis. The PoPD was polymerized on the metal surface as thin, transparent layers with a ladder conductive polymer structure. Results showed that the charge transfer resistance of the PoPD coating were higher (8.17 K Omega and 3.28 K Omega) when compared to a pristine and bacterial inoculated system (2.60 Omega and 0.23 K Omega). The PoPD coating effectively inhibits the adhesion of biofilm on AA 2024 due to its biocidal property, demonstrating that PoPD is a novel and superior candidate for the inhibition of biocorrosion by B. cereus ACE4 in an aeronautical fuel storage tank.