Inhibitive properties and surface morphology of a group of heterocyclic diazoles as inhibitors for acidic iron corrosion.
The heterocyclic diazoles 3-amino-1H-isoindole, indazole, imidazole, 4-bromoimidazole, 4-methylimidazole, pyrazole, 4-nitropyrazole, and 4-sulfopyrazole were investigated as corrosion inhibitors of iron in 1 M HCl using ac and dc techniques. The polarization curves showed a decrease in corrosion current for the inhibitor-containing solution. Impedance spectra demonstrate that the charge-transfer resistance in the presence of these inhibitors was greater than in inhibitor-free solution, except for 4-nitropyrazole. The resistance increased with inhibitor concentration and with immersion time. The structural and electronic parameters of these diazoles were calculated using computational methodologies. The elemental composition and the speciation of the treated surfaces were investigated via XPS measurements, and morphological changes were monitored by vertical scanning interferometery.
Babić-Samardzija
Ksenija
K
Department of Chemistry, Rice University, Houston, Texas 77005, and Department of Earth Science, Rice University, Houston, Texas 77005, USA.
Lupu
Corina
C
Hackerman
Norman
N
Barron
Andrew R
AR
Luttge
Andreas
A