在SiO2玻璃衬底上用脉冲激光沉积(PLD)技术,分别沉积Ti和Ti/Al膜,经电化学阳极氧化成功制备了多孔TiO2/SiO2和TiO2/A1/SiO2纳米复合结构。其中TiO2薄膜上的微孔阵列高度有序,分布均匀。实验研究了Al过渡层对多孔TiO2薄膜光吸收特性的影响。结果表明:无Al过渡层的多孔TiO2薄膜其紫外吸收峰在270nm处,且峰强不随阳极氧化工艺参数调节;而有Al过渡层的多孔TiO2薄膜其紫外吸收峰红移至293nm处,峰强和峰形不仅受阳极氧化电压调节而且受Al过渡层厚度的影响也很敏感。进一步分析了两种结构在吸收边附近的光跃迁特性。这些结果对基于多孔TiO2的光伏电池和紫外光传感器的应用研究非常有益。
The porous TiO2/SiO2 and TiO2/A1/SiO2 nanostructures are successfully fabricated by anodic oxidation of titanium or titanium/aluminum thin films deposited on transparent SiO2 glass substrates with pulsed laser deposition (PLD) technique. The optically transparent titania films, with highly ordered and uniformly arrayed pores are characterized by field emission scanning electron microscope (FESEM). The influence of A1 buffer layer on the optical absorption of the porous TiO2 thin films was investigated. The results show that without A1 buffer layer the UV absorption peak of the porous TiO2 131ms was fixed at 270 nm and the intensity of absorption peak was not modulated by the anodic potential. However, with an A1 buffer layer, the UV absorption peak will shift to 293 nm, and the intensity of absorption peak was not only modulated by anodic potential, but also sensitively influenced by the thickness of A1 buffer layer. Moreover, the optical transition property of the two nanostructures at the absorption edge was analysed.