铜电极在缓蚀协同作用过程中光电化学行为的转变

STUDY ON PHOTODELTROCHEMICAL BEHAVIOR OF COPPER ELECTRODE IN SYNERGISTIC EFFECT OF CORROSION INHIBITION

采用光电化学方法考察了铜缓蚀剂苯并三唑(BTA)分别与咪唑(IM)和8-羟基喹啉(HQ)的复配效果。实验表明:在电位正向扫描过程中,高浓度的IM能使铜电极的光响应从p-型转变为n-型,而HQ却不能使铜电极的光电流发生转型;在电位负向扫描过程中,HQ能使铜电极产生的阴极光电流峰值明显增大。IM和HQ分别与BTA复配后导致铜电极产生不同的光电化学响应行为。采用MM2分子力学程序和PPP-SCF量子化学方法计算了它们的分子结构参数,分析讨论了它们之间的缓蚀协同作用:IM能够促进BTA在铜表面的吸附和成膜,而HQ能够维持铜表面[Cu(I)BTA]膜的致密性和完整性。

The photoelectrochemical behavior of copper electrode in borax buffer solutions containing imidazole（IM） and 8-hydmxyquinoline（HQ） and the synergistic effects of IM or HQ with benzotriazole（BTA） were investigated by photoelectrochemical methods. The photocurrent response for Cu electrode in solutions containing 20mg/L IM exhibits n type during anodic polarization, while the addition of HQ d oesn＇ t change the photocurrent response of the electrode from p-type to ntype. The cathodic photocurrent value was increased by the addition HQ during the cathodic polarization. It was shown that the complex inhibitors for copper corrosion have the same photoelectrochemical properties as the combination of the singular ingredient. The molecular structure parameters of IM and HQ and BTA were obtained via MM2 forcefield program and PPP-SCF quantum chemical calculation. The synergistic effect between IM and BTA was attributed to the electron transfer between them and thus resulted in a more stable protective complex film, while HQ favored the formation of a more compact protective layer.