NaCl溶液中BTA对Cu腐蚀的缓蚀机理

The corrosion behavior of BTA corrosion inhibition on Cu in NaCl solution

为了更深入了解缓蚀剂在金属表面的缓蚀机理,采用极化曲线、电化学阻抗谱法(EIS)、扫描电子显微镜(SEM)和X射线能谱分析(EDAX)研究了BTA对Cu在NaCl溶液中的缓蚀作用和吸附规律。实验从电子转移的角度揭示了在不同施加电压下极化曲线的形成过程,结果表明:BTA能够同时抑制阳极反应和阴极反应的进行,属于混合型缓蚀剂,并且随着缓蚀剂浓度的增加,缓蚀效果依次增大,当浓度增大到一定值时,缓蚀机理发生改变,由半无限扩散行为转变为球形扩散行为。吸附过程为自发过程,物理吸附和化学吸附同时存在,且服从Langmuir吸附等温式。BTA对Cu的缓蚀机理为缓蚀剂在Cu表面形成单层保护膜阻止腐蚀性离子对Cu的腐蚀。

In order to understand the corrosion inhibition mechanism on the metal surface,the adsorption and corrosion inhibition of BTA on Cu surface in NaCl solution were analysed by using the polarization curve,electrochemical impedance spectroscopy（EIS）,scanning electron microscope（SEM）and energy dispersive X-ray analysis（EDAX）.The experiment result reveals the formation of the polarization curve in different applied voltage from the point of view of electron transfer.And BTA can suppress the proceeds of the anodic reaction and the cathodic reaction at the same time,therefore,it is a mixed inhibitor.Furthermore,the inhibition effect increases gradually along with the increase of the inhibitor concentration.The inhibition mechanism changed from a semi-infinite diffusion behavior into a spherical diffusion behavior when the concentration increases to a certain value.The adsorption process is a spontaneous process,which obeys the Langmuir isotherm as well.During this process,there are physical adsorption and chemisorption at the same time.In general,the inhibition mechanism is the formation of a single protective film on the copper surface to prevent the corrosion of copper.