The inhibition performance of three selected dihydrazide
derivatives, namely, malonic acid (MAD), succinic acid (SAD),
and adipic acid (AAD) dihydrazide, was tested in relation
to nickel corrosion in 1.0 M sulfuric acid (H2SO4) solution.
Electrochemical methods (Tafel polarization, linear polarization
resistance [LPR], and electrochemical impedance spectroscopy
[EIS]) were used, complemented with scanning electron
microscopy/energy-dispersive x-ray (SEM/EDX) examinations.
Computational studies were also used to confirm experimental
findings and to optimize the adsorption structures of dihydrazide
derivatives. Results showed that the three tested dihydrazides
inhibited Ni corrosion (mixed-type inhibitors) to an
extent, depending on the type and concentration of the introduced
inhibitor. SEM studies revealed that the corroded areas
on the surface were decreased in the presence of additives
to an extent, depending on the type and concentration of the
tested inhibitor. Results obtained from electrochemical measurements
are in good agreement with theoretical studies |