纳米锌镀层在硫酸中的腐蚀和缓蚀机理

Corrosion and Inhibition Mechanism of Zinc Nanocrystalline Electrodeposition in Sulfuric Acid Solutions

用失重法测试了纳米锌镀层和0#锌片在0.2 mol/L硫酸介质中的腐蚀性能.结果表明纳米锌镀层的耐腐蚀性要远优于锌片,且在一定的实验条件下,纳米锌镀层的腐蚀速率为一常数.另外,本文还研究了溴化十六烷基吡啶和吡啶及其甲基衍生物在硫酸介质中对纳米锌镀层和0#锌片的缓蚀性能.其中溴化十六烷基吡啶和3-甲基吡啶的缓蚀性能较好.并用密度泛函B3LYP方法和Onsager溶剂化模型,在6-31G*水平上优化了溴化十六烷基吡啶、3-甲基吡啶和4-甲基吡啶分子的几何构型,用其电子结构数据探讨了它们的缓蚀机理.

The corrosion behaviors of 0^# zinc and zinc nanocrystalline electrodeposition in 0.2 mol/L H2SO4 solution have been studied by weight-less method. The results show that the corrosion resistance of zinc nanocrystalline electrodeposition is much better than that of 0^# zinc. In the experimental condition, the corrosion rate of zinc nanocrystalline electrodeposition is a constant. The inhibiting properties of bromo-hexadecyl pyridine, pyridine and its derivatives for the 0^# zinc and the zinc nanocrystalline electrodeposition in the H2SO4 solution have been determined, respectively. The inhibiting efficiency of bromo-hexa- decyl pyridine and 3-methyl pyridine is higher than that of the others. The geometries of bromo-hexadecyl pyridine, pyridine and its derivatives have been optimized by the B3LYP/6-31G＊ and Onsager reaction field model, respectively. The inhibiting mechanism was discussed according to the data of the electronic structure of the molecules.