基于阳极氧化法的TiO2纳米管制备及生成过程分析

Preparation of titanium dioxide nanotubes by anodic oxidation and analysis of the formation process

运用阳极氧化法制备TiO2纳米管,探讨了TiO2纳米管紫外光催化净化头孢噻肟钠抗生素废水的效果,采用扫描电镜(SEM)和X射线衍射仪(XRD)对TiO2纳米管进行了表征分析。SEM结果显示,制备的TiO2材料表面呈阵列排布的多孔状,内径大小均匀,管径分布在30~45nm之间,管阵列呈蜂窝状,与钛板表面垂直,对比煅烧前后的TiO2纳米管XRD图,发现煅烧后样品的XRD图出现了TiO2锐钛矿型特征衍射峰和金红石型特征衍射峰。讨论了TiO2纳米管的生成机理,认为纳米管的形成过程主要有最初氧化层的形成、孔核的形成、由孔核演变成微孔、微孔生长并出现空隙、形成纳米阵列管过程。

In this paper, TiO2 nanotubes were prepared using an anodic oxidation method, and their performance in the photocatalytic degradation of cefotaxime in wastewater was discussed. The TiO2 nanotubes were characterized by scanning electron microscope and X-ray diffraction. The SEM images showed that the surface of the prepared titanium dioxide was porous and the inner diameter distribution was uniform. The diameters of the tubes were distributed in 30-45 nm. The tube arrays were honeycomb-like and perpendicular to the surface of the titanium plate. Compared with the XRD images of the TiO2 nanotubes before and after calcination, that after calcination showed the characteristic diffraction peaks of anatase and rutile types. The formation mechanism of TiO2 nanotubes during the electrolysis process was discussed, which might include five stages: the formation of initial oxide layers, the architecture of pore nucleus, the evolution of pore nucleus into micropores, the growth of micropores with gap appearance, and the final formation of the target nanotube arrays.