吡咯烷二硫代氨基甲酸铵自组装膜对铜的缓蚀作用

吡咯烷二硫代氨基甲酸铵(APDTC)是一种环境友好型金属缓蚀剂, 以其在铜表面制备了自组装单分子膜(SAMs), 用电化学方法研究在0.5 mol·L-1 HCl介质中APDTC SAMs对铜的缓蚀作用及其吸附行为. 结果表明, APDTC分子易在铜表面形成稳定的APDTC SAMs, 改变了电极表面的双电层结构, SAMs同时抑制了铜的阳极氧化过程和阴极还原过程, 铜电极的电荷转移电阻明显提高, 双电层电容明显降低. 电化学阻抗和极化曲线测试结果显示, 在0.5 mol·L-1 HCl介质中, 铜表面APDTC SAMs表现出良好的缓蚀效果. 研究结果还表明, APDTC的吸附行为符合Langmuir吸附等温式, 吸附机理是介于化学吸附和物理吸附之间的一种吸附.

Corrosion Inhibition Effect of Self-Assembled Monolayers of Ammonium Pyrrolidine Dithiocarbamate on Copper

Ammonium pyrrolidine dithiocarbamate (APDTC) is an environmentally friendly corrosion inhibitor. The anticorrosion mechanism and adsorption behavior for the self-assembled monolayers (SAMs) of APDTC on the surface of copper in 0.5 mol·L-1 HCl solution were investigated by electrochemical methods. Results indicated that APDTC was liable to interact with copper forming SAMs on the surface of copper. APDTC SAMs changed the structure of the double electric layer and restrained both the processes of anodic oxidation and cathodic reduction. Electrochemical impedance spectroscopy (EIS) measurement results indicated that the charge transfer resistance of the copper electrode with APDTC SAMs increased greatly and its double electric layer capacitance decreased significantly. This is in good agreement with the fact that APDTC SAMs have a high inhibition effect on copper in 0.5 mol·L-1 HCl solution measured by EIS and by polarization curves. Adsorption of APDTC SAMs was found to follow Langmuir's adsorption isotherm and the mechanism consisted of a mixed adsorption between chemisorption and physisorption.