阳极氧化法制备有序纳米多孔氧化铝膜的研究

利用电化学阳极氧化的方法,在草酸溶液中,精确控制反应条件,在高纯铝片表面有序生长了纳米多孔氧化铝膜。试验中,分别采用一次阳极氧化和二次阳极氧化方法制备氧化铝膜。利用H3PO4溶液浸泡法对氧化铝膜进行扩孔处理。通过扫描电子显微镜对样品进行表征分析。结果发现,二次阳极氧化制备的氧化铝膜的孔洞分布较一次氧化的更为规则有序,并且孔径大小均匀一致。扫描电镜观察显示,氧化铝膜的扩孔过程可以去掉阻碍层,并调节孔径大小,溶去二次氧化后黏附在氧化层表面的一些杂质,从而使氧化铝模板更为规则有序,孔径均一。这种经过二次阳极氧化和扩孔处理得到多孔阳极氧化铝模板的方法简单,成本较低,可以为后续的纳米材料合成提供高质量的合成模板。

Fabrication of Porous AAO Nano Membrane Through Electrochemical Anodization

As known,porous alumina membrane is a type of template for fabricating nano-structural materials.By using electrochemical anodization method with two-step anodic oxidation and H3PO4 solution etching treatment,anodic aluminum oxide(AAO) membrane with nano-sized pore structure on the surface of high purity aluminum sheet was synthesized.SEM observation indicates that the membrane with ordered and hexagonally packed pore structure has been formed through the electrochemical anodization and the pore diameter is about 70nm.Compared with the one-step anodic oxidation,the AAO membrane obtained from the two-step anodic oxidation shows large improvement in the regularity of porous distribution and the arrangement of holes.It is also found that the subsequent etching treatment in a H3PO4 solution can remove the barrier layer on AAO membrane and improve the regularity of holes.Electrochemical anodization proves to be a simple approach to prepare high-quantity AAO membrane with ordered and hexagonally packed pore structure,which could provide an ideal model for synthesizing 1D nano-materials.