Study Of Effects Of The Inhibitive Film On Corrosion Of Copper In NaCl Solution

Copper is easy to be corrosion in the presence of aggressive ions,so study of corrosion and protection of copper is very important theoretically and practically.In this paper,inhibitive effects of the mixed self-assembled monolayer,Cu₉S₅ and C₁₈H₃₆O₂ films,BTESPT Silane filmon corrosion of copper were studided by using scanning eletrochemical microscopy?SECM?combined with EIS and Tafel method.The main work of this paper is as follows:1.Effects of AC treatment on inhibitive ability of the self-assembled monolayers on the surface of copperThe inhibitive effects of alternating current-treated?AC-treated?mixed self-assembled monolayer?SAMHL/DT?with 2-?Pyridin-2-yliminomethyl?-phenol?HL?and dodecanethiol?DT?on copper corrosion have been studied by using the scanning electrochemical microscope?SECM?combined with Tafel and electrochemical impedance spectroscopy?EIS?methods When the AC-treated potential is applied in the cathodic region,the inhibition efficiency increases,and the pitting dynamic processes are inhibited.All the results reveal that the AC-treated effects are related to both the formation of complex compounds and the reduction of the oxide film on the surface of copper,thereby improving the corrosion resistance of self-assembled films.2.Inhibitive effects of Cu₉S₅ and C₁₈H₃₆O₂ films on corrosion of copper in NaCl solutionCu₉S₅ film was formed on the surface of copper substrate by impregnation method,and then was treated with 0.5 wt % stearic acid solution to form hydrophobic membrane on the copper surface;the C₁₈H₃₆O₂ film was formed on the copper surface by self-assemly method.In this paper,the effect of Cu₉S₅ and C₁₈H₃₆O₂ films on the corrosion inhibition performance was studied byelectrochemical method and XPS and EDS.the corrosion inhibition of Cu₉S₅ film was related to corrosion medium,and the corrosion inhibition of C₁₈H₃₆O₂ film was related to assembly time.The corrosion inhibition efficiency of Cu₉S₅ and C₁₈H₃₆O₂ films were 92.9%and 93.6%respectively,which can inhibit the corrosion of metal.3.Inhibitive effect of BTESPT film on corrosion of copper in NaCl solutionInhibitive effects of the BTESPT silane film on corrosion of copper were studied by using electrochemical methods and SEM.The results show that the inhibition efficiency depended on the hydrolysis time of the silane solution.The longer the hydrolysis time is,the lower the inhibition efficiency.In order to further improve the corrosion inhibition efficiency of silane film,the silane film was modified with 0.5 wt% tetradecanoic acid solution.It is found that the tetracyclic acid molecule was embedded into the space network structure to improve the compactness and stability of the silane film,thus improving the corrosion efficiency of copper metal.