水热法制备TiO_2纳米线薄膜的光生阴极保护性能

Photogenerated Cathodic Protection Properties of a TiO_2 Nanowire Film Prepared by a Hydrothermal Method

应用水热法在钛箔表面制备TiO2纳米线薄膜,采用场发射扫描电子显微镜、X射线衍射和紫外-可见分光光度法对薄膜进行表征,用电极电位和电化学阻抗谱考察TiO2光生阴极保护性能.结果表明:薄膜由纵横交错的锐钛矿型TiO2纳米线组成,纳米线的直径约10nm.在150℃下反应6h生成的TiO2纳米线薄膜在0.3mol·L-1 Na2SO4溶液和0.3mol·L-1 Na2SO4+0.5mol·L-1 HCOOH混合溶液中对与TiO2薄膜耦连的403不锈钢均有良好的阴极保护效应.TiO2膜所在溶液中含有HCOOH时,可使耦连的403不锈钢在0.5mol·L-1 NaCl溶液中电极电位负移约545mV,界面反应电阻显著变小,表明电解质溶液加入HCOOH可以增强TiO2纳米线薄膜对403不锈钢的光生阴极保护效应.

A TiO2 film was synthesized on the surface of a Ti substrate by a hydrothermal method,followed by acid treatment and calcination.The properties of the TiO2 film were characterized by scanning electron microscopy,X-ray diffraction,and ultraviolet-visible spectrophotometry.The photogenerated cathodic protection properties of the TiO2 film were investigated by electrochemical techniques.The corrosion performance of 403 stainless steel coupled to a TiO2 film photoanode in different solutions was evaluated by photogenerated potential and electrochemical impedance spectroscopy.The results showed that the TiO2 film was composed of many randomly-oriented anatase nanowires of about 10 nm in diameter.The TiO2 nanowire film prepared by the hydrothermal reaction at 150 ℃ for 6 h was used for the photogenerated cathodic protection of 403 stainless steel.When we coupled the steel in a 0.5 mol·L -1 NaCl solution to the TiO2 film photoanode in a mixed solution containing 0.3 mol·L-1 Na2SO4 and 0.5 mol·L-1 HCOOH,its potential decreased by 545 mV.Additionally,the charge transfer resistance of the electrode reaction process for the coupled steel decreased considerably.The results also indicated that the HCOOH in the mixed solution improved the photogenerated cathodic protection of the TiO2 film photoanode.