(中南大學(xué) 化學(xué)化工學(xué)院，長(zhǎng)沙 410083)
摘 要: 采用交流阻抗(EIS)、塔菲爾(Tafel)極化曲線和循環(huán)伏安法(CV)研究了銅表面3-己基-4-氨基-1,2,4-三唑-5-硫酮(HATT)和5-己基-1,2,4-三唑-3-硫酮(HXTT)自組裝膜抗0.5 mol/L鹽酸溶液腐蝕的電化學(xué)性能。通過接觸角、吸附熱力學(xué)和X射線光電子能譜分析，探究HATT和HXTT在銅表面的自組裝機(jī)理。結(jié)果表明：HATT和HXTT在銅表面的自組裝單層膜都能很好地延緩銅的腐蝕。銅表面經(jīng)5×10-5 mol/L HATT和HXTT處理24 h，后所生成的自組裝膜對(duì)銅在0.5 mol/L鹽酸溶液中的緩蝕效率分別達(dá)到97.33%(HATT)和95.51%(HXTT)，HATT的效果更佳。HATT和HXTT都通過其分子中的氮、硫原子與Cu原子結(jié)合生成Cu(I)絡(luò)合物而化學(xué)吸附于銅金屬表面，形成致密的自組裝單層膜，阻隔溶液中Cl-等腐蝕粒子擴(kuò)散至銅表面，起到緩蝕作用。與此同時(shí)，自組裝膜中烷基朝外面向溶液，使銅表面由親水性轉(zhuǎn)化成疏水性。
關(guān)鍵字: 己基三唑硫酮；自組裝單層膜；交流阻抗；Tafel曲線；循環(huán)伏安；銅防腐
（School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China）
Abstract:The electrochemical properties of the self-assembled monolayer(SAM) of 3-hexyl-4-amino-1,2,4-triazole- 5-thione (HATT) or 5-hexyl-1,2,4-triazole-3-thione (HXTT) on copper surfaces were investigated by electrochemical impedance spectroscopy (EIS), Tafel polarization curve and cyclic voltammetry (CV). The results show that the SAM of HATT or HXTT exhibits the excellent resistance to copper corrosion. And the SAM formed on copper surfaces by 5×10-5 mol/L HATT or HXTT treatment of 24 h reaches corrosion inhibition efficiency of 97.33% or 95.51% to copper in 0.5 mol/L hydrochloric acid solution, respectively. The self-assembly mechanism of HATT or HXTT on copper surfaces was further evaluated by contact angle, adsorption thermodynamics and X-ray photoelectron spectra. The result indicates that HATT and HXTT chemisorbed on copper surfaces through bonding their N and S atoms with surface copper atoms to generate Cu(I) complexes. The closely arranged SAM might obstruct the corrosion particles, such as Cl- ions to diffuse to copper surfaces, resulting in corrosion inhibition. Moreover, the alkyl of the SAM faces to aqueous solutions to convert copper surfaces from hydrophilicity to hydrophobicity.
Key words: hexyl triazole-thione; self-assembled monolayer(SAM); electrochemical impedance spectroscopy (EIS); Tafel polarization curve; cyclic voltammetry (CV); copper corrosion inhibition
