Enhanced active corrosion protection coatings for aluminum alloys with two corrosion inhibitors co-incorporated in nanocontainers

Abstract

An active corrosion protection coating was developed based on mesoporous SiO2 nanoparticles simultaneously incorporated with benzotriazole and 2-mercaptobenzothiazole inhibitors (BTA+MBT@mSiO2 NPs). The enhanced inhibition effect between BTA and MBT mixtures against the corrosion of aluminum alloy (AA2024-T3) was assessed through a visual-identification based high-throughput screening method and EIS measurement. DFT and MD simulation revealed that the hydrogen bond interaction between BTA and MBT promoted their co-adsorption on the alloy surface. An epoxy coating containing 2 wt% BTA+MBT@mSiO2 NPs exhibited enhanced active corrosion protection of AA2024-T3 in 3.5 wt% NaCl solution. XPS results confirmed the adsorption of binary inhibitors to suppress corrosion.