Premium
Corrosion inhibition of LY12CZ aluminum alloy by 3‐pyridyl‐4‐amino‐1,2,4‐triazole‐5‐thiol and its cerium nitrate compound
Author(s) -
Liu Cui,
Yu Jin,
Sun Shuo
Publication year - 2019
Publication title -
materials and corrosion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 55
eISSN - 1521-4176
pISSN - 0947-5117
DOI - 10.1002/maco.201810660
Subject(s) - cerium , cerium nitrate , adsorption , physisorption , chemisorption , chemistry , langmuir adsorption model , corrosion , dielectric spectroscopy , inorganic chemistry , nuclear chemistry , electrochemistry , organic chemistry , electrode
The inhibition effect of 3‐pyridyl‐4‐amino‐1,2,4‐triazole‐5‐thiol (C 7 H 7 N 5 S) and its cerium nitrate (Ce(NO 3 ) 3 ) compound on the corrosion of LY12CZ aluminum in 3.5% NaCl was investigated by means of potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). Results showed that the inhibition efficiency reached 77.61% at 0.8 g L −1 concentration and was found to increase with increasing concentration of C 7 H 7 N 5 S. C 7 H 7 N 5 S is a mixed type inhibitor. The desorption onset potential was obtained from differential polarization curve. EDS data indicated that C 7 H 7 N 5 S can adsorb on the S phase and inhibit the cathode action of the S phase. Both kinetic and thermodynamic parameters were calculated and discussed. The adsorption of C 7 H 7 N 5 S on aluminum surface was found to obey the Langmuir adsorption isotherm, and being both physisorption and chemisorption. C 7 H 7 N 5 S and Ce(NO 3 ) 3 have an additive inhibition effect. The additive action improved the surface coverage of the aluminum and the stability of the adsorbed layer.