阳极氧化铝膜的制备及自组织细微结构

Fabrication and self-organization fine-structure of anodic aluminum oxide films

以草酸溶液为电解液,选用高纯(>99.99%)铝箔,氧化电压为40V直流,两步氧化法制备了较大面积的多孔氧化铝膜(AAO);采用CuC l2溶液剥离铝基底;分别用扫描电镜和原子力显微镜对AAO膜的形貌特征和孔径参数进行表征.实验结果表明,CuC l2溶液剥离铝基底的方法简单安全、无毒、无污染;两步阳极氧化法制备的多孔氧化铝膜孔径均匀、周期一致、高度有序,孔道的直径约55nm,孔间距约100nm,呈六边形,而且孔道垂直膜表面;高分辨率原子力显微镜观察到了AAO膜的更细微结构,发现每一个孔均由6个完全相同的颗粒构成,这一结果就直接解释了AAO孔道呈六边形的原因,也为进一步探索AAO自组织形成结构的微观机理提供了直观的实验依据.

Large area porous anodic aluminum oxide（AAO） film was fabricated with a two-step anodization method using oxalic solution as electrolyte.Aluminum film with high purity（〉99.99%） and anodic voltage DC 40V were used.The new method of peeling AAO film off from the Al substrate by CuCl2 solution insteat of HgCl2 was used firstly.The shape properties and pore parameters of AAO film were characterized by FE-SEM and AFM.The results show that the method of peel off AAO film from the Al substrate by CuCl2 solution is easy, innocuous and safe for researchers. The shape of ordered array pores is hexagonal. The alumina pores have dimension of 55nm in diameter and 100nm pore spacing, and perpendicular to the surface of AAO film. Furthermore, the fine-structure of AAO film was observed by AFM. It can be seen clearly that each pore is constituted with six homology grains. Thus, the results may explain the observation result that each pore of AAO film is hexagonal observed by SEM images and help to study the self-organization mechanism of AAO more deeply.