The Corrosion Inhibition Effect of Triazinedithiol Inhibitors for Aluminum Alloy in a 1 M HCl Solution

Abstract

Two environmental friendly triazinedithiol inhibitors 6-diallylamino-1,3,5-triazine-2,4-dithiol monosodium (DAN) and 6-dibutylamino-1,3,5-triazine-2,4-dithiol monosodium (DBN) were synthesized and their corrosion inhibition for aluminum alloy in a 1 M HCl solution was studied using weight loss methods, electrochemical measurements, and scanning electron microscopy (SEM) techniques. The inhibition efficiency of both DAN and DBN improved with increases in inhibitor concentration but decreased with increases in temperature. Results from potentiodynamic polarization and EIS showed that the corrosion inhibition efficiency of DAN and DBN was excellent. The adsorption of inhibitors on the aluminum alloy surface followed Langmuir adsorption isotherms. Morphology observation revealed that the aluminum alloy was greatly protected by these triazinedithiol inhibitors. Further, density functional theory (DFT) was used to investigate the relationships between molecular structural and inhibition efficiency.