Corrosion inhibition of 2024-T3 aluminum alloy in 3.5% NaCl by thiosemicarbazone derivatives

Highlights: • Thiosemicarbazone derivatives as corrosion inhibitors for AA2024-T3 alloy. • Evaluation of inhibition efficiency by electrochemical methods. • Predominantly anodic inhibition, through adsorbed inhibitor layers. • Corroboration of experimental studies and theoretical studies. - Abstract: Three thiosemicarzone derivatives, namely (E)-2-(2-hydroxybenzylidene) hydrazinecarbothioamide(MHC), (E)-2-(2,4-dihydroxybenzylidene)hydrazinecarbothioamide (DHC) and (E)-2-(2,3,4-trihydroxybenzylidene)hydrazinecarbothioamide (THC) were synthesized and their corrosion inhibition action on 2024-T3 aluminum alloy was studied in 3.5% NaCl solution. The surface morphology and surface composition of the corroded alloy were examined using FESEM, 3D profilometry, EDX spectroscopy and X-ray photoelectron spectroscopy. The synthesized inhibitors were found to provide corrosion protection on AA2024-T3 by forming an adsorbed layer of the complex on the alloy surface. They exhibited inhibition efficiency in the order, MHC < DHC < THC. Quantum chemical calculations corroborated the experimental results.