The Synergistic Effect of BTA-Co System on the Corrosion Inhibition of Mild Steel in 3.5 wt% NaCl Solution

In this study, the synergistic effect of benzotriazole (BTA) molecules and cobalt cations (Co2+ cations) on the corrosion inhibition of mild steel was studied by electrochemical and surface analysis techniques. The considerable corrosion inhibition efficiency of BTA-Co system was proved by open circuit potential measurements, polarization tests, and electrochemical impedance spectroscopy (EIS) results. Field-emission scanning electron microscopy, energy dispersion spectrometer, X-ray photoelectron spectroscopy, and EIS analysis were employed to characterize the inhibition mechanism of the BTA-Co system. The precipitation of BTA-Co chelate on the steel surface was proposed as the main mechanism for corrosion protection of mild steel in the presence of BTA molecules and Co2+ cations. Also, a mixed-type corrosion inhibition effect of BTA-Co system was shown by polarization tests. (C) 2018 The Electrochemical Society.