直接在Ti基底表面制备的三维微纳米复合结构TiO2具有比表面积大、光利用效率高、电荷传输阻抗小的优势。采用飞秒激光对Ti片进行刻蚀制备微米结构,使用H2O2在微米结构表面氧化制备纳米多孔TiO2。该复合方法制备的三维微纳米复合结构TiO2在紫外波长范围内平均反射率低于5%。光催化降解甲基橙结果显示,飞秒激光制备的微米结构形状和尺寸特征对催化性能有显著影响。该复合结构性质稳定,多次降解循环速率保持不变。飞秒激光化学复合制备的方法可以充分发挥飞秒激光在Ti基底表面超精密、可控制备的优势,对实现金属表面金属氧化物功能材料的制备具有重要意义。
In situ-fabricated three-dimensional micro/nanostructure TiO2 films over titanium substrates possess advantages such as large specific surface area, high light efficiency, and good electron conductivity. Titanium substrates are ablated by femtosecond laser for fabricating micron structures. Then it is processed by chemical oxidation with H2 O2 to form nanoporous TiO2 on the surface of micron structures. The average reflectance of the as-fabricated three-dimensional TiO2 structure is below 5 % over the ultraviolet wavelength range. The photocatalytic degradation of methyl orange shows that catalytic performance is largely determined by the size and morphology of the micro structures prepared by femtosecond laser. Additionally, the photo degradation rate remains constant over several consecutive cycles, which indicates that the micro/nanostructure TiO2 film is mechanically stable. The fabrication method of femtosecond laser combined with chemical oxidation can fully play advantages of ultraprecise on titanium substrate surface and controllable fabrication. The insights from the study on the fabrication of micro/nanostructure TiO2 film can be extended to guide the fabrication of other functional metal oxides on metallic substrates.