多级有序氧化物.ppt

Hierarchically Ordered Oxides Peidong Yang, Tao Deng, Dongyuan Zhao, Pingyun Feng, David Pine, Bradley F. Chmelka, George M. Whitesides, Galen D. Stucky* Porous silica, niobia, and titania with three-dimensional structures patterned over multiple length scales were prepared by combining micromolding, polystyrene sphere templating, and cooperative assembly of inorganic sol-gel species with amphiphilic triblock copolymers. The resulting materials show hierarchical ordering over several discrete and tunable length scales ranging from 10 nanometers to several micrometers. The respective ordered structures can be independently modiTed by choosing different mold patterns, latex spheres, and block copolymers. The examples presented demonstrate the compositional and structural diversities that are possible with this simple approach. 多个尺度的具有三维结构的多孔二氧化硅，氧化铌，以及二氧化钛构图被制备通过微模塑相结合、聚苯乙烯球模板、和无机溶胶-凝胶的协同装配与两亲性三嵌段共聚物。所得到材料的结果表明多个离散的分级排序，可调尺度范围从10纳米到几微米。各有序结构能够被独立修改，通过选择不同的模具图案、乳胶球以及嵌段共聚物。这个呈现的示例表明，用这个简单的方法是可能的对于成分和结构的多样性。 1、Several approaches are currently available for the preparation of ordered structures at different length scales. For example, organic molecular templates can be used to form crystalline zeolite-type structures with ordering lengths less than 3 nm (1); mesoporous materials with ordering lengths of 3 to 30 nm can be obtained using surfactants or amphiphilic block copolymers as structure-directing agents (2–7); the use of latex spheres yields macroporous materials with ordering lengths of 100 nm to 1 mm (8–13); and soft lithography can be used to make high-quality patterns and structures with lateral dimensions of about 30 nm to 500 mm (14–16). Despite all of these efforts in nanostructuring materials, the fabrication of hierarchically ordered structures at multiple length scales, such as seen in nature in diatoms (17), has remained an experimental challenge. 目前有几种可用于制备在不同尺度上的有序结构的方法。例如，有机分子模板可以用于形成具有有序长度少于3nm的结晶沸石型结构；具有有序长度为3-30nm的介孔材料能够获得，通过使用表面活性剂或者两亲性嵌段共聚物作为导向剂；使用