A comparative experimental and theoretical calculation study of CaAl-LDH modified with various aromatic inhibitors for corrosion protection study in epoxy coatings

The in-depth influence mechanism of the functional groups and conjugated structure of aromatic inhibitor on the corrosion protection ability of CaAl layered double hydroxide (CaAl-LDH) in epoxy coatings was investigated by performing the inhibitor modification using three typical aromatic inhibitors. The electrochemistry impedance spectroscopy (EIS) measurement demonstrated that CaAl-LDH-MBT showed superior protection for carbon steel in epoxy coatings. Density functional theory (DFT) calculation and molecular dynamic (MD) simulation indicated that the aromatic conjugated structure with larger π electron clouds and heteroatoms with lone pair electrons would contribute to the enhanced corrosion protection.