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采用循环伏安沉积法在 TiO2纳米管表面构筑了石墨烯和 CdSe，其中 TiO2纳米管是由阳极氧化法制备而成。通过扫描电镜（SEM）及能谱（EDS）、X 射线衍射分析（XRD）和紫外可见漫反射吸收光谱（UV-vis DRS）等测试方法观察了复合膜的表面形貌、晶型和光响应特征；通过测试可见光照射前后电极的开路电位（OCP）、电化学阻抗谱（EIS）等研究了复合膜对304不锈钢的阴极保护效果。结果表明，锐钛矿相的 TiO2纳米管阵列膜排列紧密，孔径约为30～60 nm；石墨烯和立方晶相的 CdSe 均匀地覆盖在 TiO2膜表面，在纳米管口与管壁均有分布；可见光照射下，与复合膜耦合的304不锈钢的电位可以从－180 mV 降至－900 mV（SCE），与纯 TiO2相比，电位更负。另外，切断电源后，复合膜能够对不锈钢起到延时保护作用并达到12 h 以上，这说明复合膜能够有效地解决暗态下 TiO2光生电子空穴对易复合的问题，改进 TiO2对304不锈钢的光生阴极保护效果。

The composite of CdSe/graphene/TiO2 nanotube film was fabricated by cyclic voltammetric deposition of graphene and CdSe on the surface of TiO2 prepared by anodic oxidation process.The composite was characterized by scanning electron microscopy (SEM)and energy-dispersive X-ray spectroscopy (EDS),X-ray diffraction (XRD), UV-visible diffuse reflectance spectra (UV-vis DRS).The photocathodic protection properties of the composite for 304 stainless steel were examined by the open circuit potential (OCP)and electrochemical impedance spectroscopy (EIS).It′s shown that the anatase TiO2 nanotube films were arranged closely and the diameter ranged from 30 to 60 nm.Graphene and cubic CdSe covered the TiO2 evenly and distributed on the mouth and walls of the nanotube arrays.Under visible light illumination,the OCP of the 304 stainless steel coupled with the composite film dropped from -180 mV to -900 mV (SCE).Compared with pure TiO2 ,the photopotential of the composite film was more negative.When the light was cut off,the photocathodic protection of the composite could maintain more than 12 h.It indicates that this can solve the recombination of photoinduced electrons and holes within the TiO2 film.