Electrochemical, surface analytical and quantum chemical studies on Schiff bases of 4-amino-4H-1, 2, 4-triazole-3,5-dimethanol (ATD) in corrosion protection of aluminium in 1N HNO3

Bulletin of materials science

K Mohammad Ali¹  Sam John¹  Abraham Joseph¹ 

[1] Department of Chemistry, University of Calicut, Calicut 673 635, India$$Department of Chemistry, University of Calicut, Calicut 673 635, IndiaDepartment of Chemistry, University of Calicut, Calicut 673 635, India$$

关键词: Aluminium;    acid solutions;    EIS;    polarization.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

The present study describes the inhibition of aluminium in 1N HNO₃ with different concentrations of 1,2,4-triazole precursors ATD, BATD and DBATD using gravimetric method, potentiodynamic polarization studies (Tafel), electrochemical impedance spectroscopy (EIS), adsorption studies, surface morphological studies and quantum chemical calculations at 298 K. Polarization studies clearly showed that ATD, BATD and DBATD act as mixed type inhibitors. As the electron density around the inhibitor molecule increases due to substitution, the inhibition efficiency also increases correspondingly. Quantum chemical approach was used to calculate some electronic properties of the molecule to ascertain the correlation between inhibitive effect and molecular structure of the inhibitor. The corrosion inhibition efficiencies of these molecules and the global chemical reactivity relate to some parameters, such as 𝐸_HOMO, 𝐸_LUMO, gap energy (ð›�? 𝐸), electronegativity (ðœ�?), global hardness (ðœ�?) and the fraction of electrons transferred from the inhibitor molecule to the metallic atom (ð›�? ð‘�?). In addition, the local reactivity has been analysed through the Fukui function and condensed softness indices. Both the experimental and theoretical studies agree well in this regard and confirm that DBATD is a better inhibitor than BATD and ATD. The adsorption behaviours of molecules on the copper surface have been studied using molecular dynamics method and density functional theory. The order of inhibitory action is DBATD > BATD > ATD.

【 授权许可】

Unknown