Improved anticorrosive performance of epoxy coating by introducing a one-pot synthesised nano-ceria embedded lamellar polyaniline/kaolinite hybrid

Abstract

This study presents an innovative and uncomplicated approach to produce ceria-decorated lamellar polyaniline utilising interfacial oxidative polymerisation, with ceric ammonium nitrate as both the aniline oxidiser and the ceria precursor. The study found that a 1 % weight of active polyaniline/ceria hybrid provides better corrosion protection. The addition of barrier kaolinite further enhances the protective properties of the hybrid. The study also proposes a mechanism for the synergistic function of ceria, polyaniline, and kaolinite in achieving better protective performance of the coating in harsh saline environments. The EIS results indicate that the cPAni_K/epoxy material shows a high |Z|_0.01Hz value of 5.59 × 10¹⁰ and two months of continuous exposure, the charge transfer resistance maintained at 2.14 × 10⁹ Ω cm². EIS results exhibited the durability of the coating in the harsh saline media. Corrosion rate shows that cPAni_K embedded epoxy displays the corrosion rate of the eight-order lower than that of the pristine epoxy coat. This newly developed active/passive hybrid pigment is eco-friendly and suitable for preventing corrosion in marine environments.