纳米TiO_2薄膜电极的制备及其光电化学响应

Preparation and photoelectro-catalytic Property of nano-TiO_2 thin film electrode

采用溶胶-凝胶法在氧化铟锡(ITO)导电玻璃上制备了纳米TiO2薄膜电极,研究了不同制备条件下TiO2薄膜的光电化学响应。利用X射线衍射仪对纳米TiO2的晶型结构进行了分析,利用原子力显微镜(AFM)对薄膜的表面形貌进行了表征。结果表明:随煅烧温度升高,锐钛矿(101)晶面的衍射峰强度增强;加入抑制剂且煅烧温度为650℃时制备的纳米TiO2为锐钛矿晶型,薄膜粒度分布均匀、尺度适宜,且表面存在一定孔隙。暂态电流测试表明:在光强为6.6mW/cm2、极化电位为+0.3V时,随着预吸附时间的延长,瞬时产生的峰值电流逐渐增大;当预吸附时间为300s时,随着煅烧温度的升高,TiO2薄膜电极对H2O分子的催化氧化光电流由24.2μA(450℃)提高到49.0μA(650℃)。

Nano-TiO2 thin film electrodes were prepared on conductive indium-doped tin oxide（ITO）coated glass substrates by sol-gel method.The photocurrent of different TiO2 nanostructured film electrodes were detected to study their pohtocalytic activity by employing linear sweep voltammetry and transient technique.The crystalline structure and surface morphology of TiO2 films were characterized by X-ray diffraction（XRD）and atomic force microscope（AFM）.It was found that the intensity of the diffraction peak of the anatase（101）plane increased as the calcining temperature increased.when the inhibitor was added and calcining temperature was 650℃,nanoporous TiO2 films with uniform sizes of particles and good crystallinity were obtained.From different photocurrent profiles.It was concluded that the longer the pre-adsorption time of H2 O molecule,the higher the pike photocurrent was.The diagram of transient photocurrent-time profiles of different nano-TiO2 thin films observed at＋0.3Vand pre-adsorption time 300 sindicating that the photocurrent was increased from 24.2μA to 49.0μA with increasing of calcining temperature from 450℃ to 650℃ under light intensity of6.6mW/cm2.