孔径纳米级至微米级大范围连续可调多孔阳极氧化铝模板的制备及生长机理研究

Porous anodic alumina (PAA) films have become one of the most preferred templates for the template synthesis of various nanostructures due to their excellent characteristics: tunable pore size and interpore distance, highly ordered pores, controllable thickness and good chemical inertness. Accordingly, they have been widely applied in the fields of fabrication of functional nanomaterials, sensors, energy storage, and catalysis. It has been known that the pore size of the PAA templates can determine the size of the as-prepared materials directly, thus can influence their performance in all the applications. However, the PAA templates prepared currently can only get a maximum pore size of hundreds of nanometers, limiting their practical applications to a large extent. Therefore, finding proper methods for the fabrication of PAA templates with a micron scale pore size, thus widening their application field from nanomaterials to sub-micron and micron materials, is significant from the viewpoint of both fundamental science and commercial applications. In the present project, we will try to establish a quantitative growth model of the PAA template, and fabricate PAA templates with a large-range continuously tunable pore size from nanoscale to micron scale by varying the anodization conditions. It is expected that the related findings and results can be widely used in the field of controllable fabrication of various functional nano-, sub-micron, and micron materials.

多孔阳极氧化铝（porous anodic alumina, PAA）膜由于具有孔洞大小及间距可调、孔分布高度有序、厚度可控、化学稳定性好等诸多优点，成为目前模板法构筑各种纳米结构的首选模板之一，其在功能性纳米材料的制备、传感器、能量存储、催化等众多领域获得了广泛应用。作为一种模板材料，其孔径大小将会直接决定所制备材料的尺寸，从而对其实际应用产生直接影响，而目前所制备的PAA模板，其最大孔径仅为数百纳米，从而使其应用范围受到较大限制。因此，探索合适的方法来制备具有微米级孔径的PAA模板，从而将其应用范围由传统的纳米材料领域拓展到亚微米、微米材料领域，具有重要的意义和实用价值。本项目将探索建立PAA模板的定量化生长模型，同时，通过对阳极氧化条件和扩孔条件进行设计和控制来获得孔径纳米级至微米级大范围连续可调的PAA模板，使其可以广泛应用于各种功能性纳米、亚微米、微米材料的可控化制备等领域。

多孔阳极氧化铝（PAA）膜是高纯铝经由阳极氧化过程所制备的。由于PAA膜具有孔洞大小及间距可调、孔分布高度有序、厚度可控、化学稳定性好，以及制备过程重复性好等诸多优点，成为目前模板法构筑各种纳米结构的首选模板之一，其在功能性纳米材料的制备、传感器、能量存储、催化等众多领域获得了广泛应用。本项目主要研究内容有以下四个方面：电解液体系的选择与改性；PAA模板微观结构参数与阳极氧化条件的关系；PAA模板燃烧和击穿现象的产生与控制；PAA模板生长模型的构建。重要结果主要如下：发现了一种新的自有序机制，并基于此实现了亚微米级孔间距PAA模板的快速制备；提出了PAA模板的竞争生长点模型，对PAA模板的稳态和非稳态阳极氧化过程进行了有效解释，实现了纳米/亚微米/微米多尺度复合孔PAA模板的可控制备；在最高1000V的阳极氧化电压下制备了PAA模板，对高电压阳极氧化过程进行了深入研究。基于以上研究结果可以对PAA模板的生长过程和生长机制形成更深层的认识，同时，还将进一步拓宽PAA模板的应用范围和领域。