电化学合成聚吡咯-二氧化钛复合膜及其防腐蚀性能

Electrochemical Synthesis and Corrosion Resistance of Polypyrrole-TiO_2 Composite Film

目前鲜见对电化学原位生成的聚吡咯(PPy)-二氧化钛复合膜的系统研究。采用循环伏安法,在316不锈钢表面原位生成聚吡咯-二氧化钛(PPy-TiO_2)复合材料。FT-IR分析表明,通过电化学法可以在不锈钢表面生成PPy-TiO_2复合膜。利用SEM分析了PPy膜层与PPy-TiO_2膜层表面形貌,分别将316不锈钢、316不锈钢/PPy、316不锈钢/PPy-TiO_2浸泡至3.5%(质量浓度)Na Cl水溶液中,采用开路电位-时间(EOCP-t)曲线、电化学阻抗谱(EIS)考察了不同浸泡时间下PPy膜层与PPy-TiO_2复合膜层对金属的防护效果。结果表明:生成的PPy-TiO_2膜层具有更加均一的表面状态;在浸泡初期(15 min)与浸泡60 min后,相对于PPy膜层,PPy-TiO_2膜层具有较高的膜层电阻与较低的膜层电容,PPy-TiO_2的防护效果优于PPy。

Polypyrrole- titanium dioxide(PPy-TiO_2) composite film was prepared in situ on the surface of 316 stainless steel by cyclic voltammetry method.FT-IR analysis indicated that PPy-TiO_2 composite film could be formed on 316 stainless steel surface through electrochemical process.The scanning electron microscope was used to study the morphology of PPy film and PPy-TiO_2 composite film.The 316 stainless steel,316 stainless steel/PPy,316 stainless steel/PPy-TiO_2 were soaked in 3.5%(mass concentration)NaCl aqueous solution,and the protective effect of PPy film and PPy-TiO_2 composite film on stainless steel was studied by the open circuit potential- time(E_(OCP)-t) curve and electrochemical impedance spectroscopy(EIS).Results showed that the prepared PPy-TiO_2 film had more uniform surface state.In the initial stage of immersion(15 min) and after immersion for 60 min,the PPyTiO_2 film had higher layer resistance and lower membrane layer capacitance than PPy film,which indicated that the protection effect of PPy-TiO,film was better than that of PPy film.