Corrosion behaviour of metal complexes of antipyrine based azo dye ligand for soft-cast steel in 1 M hydrochloric acid

Abstract

In this communication the corrosion behaviour of three metal [Co(II), Ni (II) and Fe (III)] complexes of Antipyrine based azo dye ligand [5-[(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)diazenyl]-6-hydroxy-1,4-dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile](L) for soft-cast steel in 1 M hydrochloric acid solution was discussed by experimental and theoretical methods. The study reveals that the ligand and their metal complexes show good inhibition efficiency. Here Ni complex shows significant inhibition efficiency at an optimized concentration of 25 mg/L. The quantum studies strengthen the experimental results of capacity of the ligand and their metal complexes acts as corrosion inhibitors for soft-cast steel in 1 M hydrochloric acid.