Enhanced inhibition of steel corrosion by L‐cysteine under visible‐light illumination. Issue 9 (24th April 2017) - Qiu, P.
Abstract : The heteroatoms such as nitrogen, oxygen, and sulfur of organic inhibitor play a crucial role on its corrosion inhibition behavior. In order to reveal their adsorption behavior and inhibition performance under illumination condition on steel surface, this study selects L‐cysteine as study object. On the basis of electrochemical measurement, surface analysis, and theoretical calculation, a promising increase in corrosion inhibition efficiency is observed when visible‐light is impinged on steel surface in sodium chloride solution with L‐cysteine. The enhanced performance is attributed to the sample surface photovoltaic effect, thereby facilitating both the thiol and the amino groups to tilt toward the surface. Abstract : The steel sample surface could cover with iron oxides and hydroxides upon contact with the sodium chloride solution, the thiol head of L‐cysteine as an inhibitor exhibits a strong affinity to adsorb on the substrate in dark condition. Essentially, L‐cysteine molecule can bond to the substrate through bridge adsorption, thiol, and amino group owing to the sample surface photovoltaic effect under visible‐light illumination condition. So we can observe an enhanced inhibition performance.