Characterization of inhibitor release from hydrotalcite pigment

Hydrotalcite doped with phosphate ion were synthesized through anion-exchange reaction. The prepared pigment was characterized by X-ray diffraction (XRD). The morphology of the pigments was determined using scanning electron microscopy (SEM). The release ability of the phosphate intercalated Zn-Al hydrotalcite in the 3.5% NaCl solution in various times was assessed by inductively coupled plasma - optical emission spectrometer (ICP-OES). The evaluation of release behavior showed that the content of phosphor increases by increasing the time. The corrosion inhibition properties of the phosphate loaded hydrotalcite nanoparticles was studied based on release ability of Zn and phosphate in solution by electrochemical impedance spectroscopy (EIS) and field emission scanning electron microscope (FESEM) tests in the 3.5% NaCl solution on the steel substrate. The results indicated significant impact of zinc and phosphor concentration on the corrosion inhibition properties.