Electrochemical and quantum chemical study of Thiazolo-pyrimidine derivatives as corrosion inhibitors on mild steel in 1 M H2SO4

• Thiazolo-pyrimidine derivatives are efficient inhibitors at room temperature.
• Physisorption was the adsorption mechanism for all the investigated compounds.
• SEM images showed dissolution of grain boundaries in the presence of inhibitors.
• Quantum chemical study provided reasonable theoretical explanation.

Inhibitive performance of a new thiazolo-pyrimidine derivative has been investigated on mild steel in a solution of 1 M H2SO4. Electrochemical measurement, scanning electron microscope analysis and quantum chemical calculations are the tests and methods used to assess the performance of the inhibitors. The results indicate that the thiazolo-pyrimidine derivative used acts as a mixed-type inhibitor retarding the anodic and cathodic corrosion reactions. The studied compounds followed the Langmuir adsorption isotherm. Thermodynamic parameters showed that inhibitor adsorption is physical as determined by those parameters. The effect of molecular structure on the inhibition efficiency was investigated by quantum chemical calculations.