2-氨基-5-巯基-1,3,4-噻二唑对青铜文物的缓蚀性能及密度泛函理论分析

采用失重法和电化学测试技术研究了2-氨基-5-巯基-1,3,4-噻二唑(AMT)作为青铜文物缓蚀剂的缓蚀效率。失重实验结果表明,在25℃、1.0×10~(3 )mmol/L的H_2SO_4和柠檬酸溶液中加入AMT后,当缓蚀剂浓度达到5.0mmol/L时,缓蚀效率可达100%。电化学分析结果表明,在28.0mmol/L NaCl+10.0mmol/L Na_2SO_4+16.0 mmol/L NaHCO_3组成的混合溶液中,当AMT的浓度达到1.0mmol/L后,缓蚀效率达到92.76%,腐蚀电流密度下降到4.71μA/cm~2。量化计算结果表明,缓蚀剂AMT分子上的活性中心主要分布在S7、S3和N6原子上,并利用Multiwfn函数分析了AMT在前线分子轨道中电子的成分比例和作用,发现对缓蚀剂AMT的理论分析与实验结果相一致。

Corrosion Inhibition of Bronze Cultural Relics by 2-aminino-5-mercapto- 1,3,4-thiadizole:a Density Functional Theoretical Analysis

Inhibitionefficiencyofthecorrosioninhibitor2-aminino-5-mercapto-1 ,3 ,4-thiadizole(AMT)tobronzecultural relics have been investigated by weight loss and potentiodynamic polarization techniques .The weight loss studies showed that the inhibition efficiency of AMT was up to 100% when the inhibitor AMT was 5 .0 mmol/L in 1 .0 × 103 mmol/L H2SO4 and citric acid solution at 25 ℃ .The electrochemical analysis showed that the inhibition efficiency was up to 92 .76% and corrosion current density dropped to 4 .71 μA/cm2 when the inhibitor AMT was 1 .0 mmol/L in 28 .0 mmol/L NaCl+10 .0 mmol/L Na2SO4 +16 .0 mmol/L NaHCO3 mixed solution .The quantum chemical calculated results indicated that the main active center distributed in S7 ,S3 and N6 atoms in inhibitor AMT ,and the effect and proportion of ingredients in frontier molecular orbit of AMT were also analyzed by Multiwfn function .It was found that the theoretical analysis was consistent with the experimental results to inhibito r A M T .