Biotemplate-assisted manufacturing of silica nanowire assemblies

本研究计划结合了分子自下而上的一维陶瓷纳米线定向成核技术，以及自上而下的策略，使用软光刻方法图案化介观材料。利用溶胶-凝胶法和溶液扩散控制成核技术，在分子溶解的多糖生物模板上，由陶瓷前驱体各向异性成核二氧化硅纳米线。生物聚合物的化学功能以及分子形状用于指导结构形成。化学基团可以从阳离子、极性或疏水性到阴离子变化。多糖将根据聚合度进行调节，聚合度限定所得纳米线的长度。分子形状可以根据糖单元之间的键的化学构型来设计。在一个组合的过程中，二氧化硅纳米线将组装成一个纳米级的光子器件使用软光刻技术，即毛细管力光刻。先进的技术将被用来测试材料（HR-TEM，EDS，AFM，XPS）和光学（椭圆偏振，干涉，FTIR显微镜）性能。排列的二氧化硅纳米线的潜在应用是作为波导的相干IR束，用于超过4微米（4 μm）的低损耗IR传输。

This research project combines the molecular bottom-up technique for oriented nucleation of one dimensional ceramic nanowires together with the top-down strategy of patterning mesoscopic materials using soft lithographic methods. Silica nanowires will be anisotropi-cally nucleated form ceramic precursors on the molecular dissolved polysaccharide biotem-plates applying sol-gel routes and diffusion controlled nucleation from solution. The chemical functions as well as the molecular shape of the biopolymers are used for directing structure formation. The chemical groups can be varied from cationic, via polar or hydrophobic to ani-onic. The polysaccharides will be adjusted in respect to the degree of polymerisation which defines the length of the resulting nanowires. The molecular shape can be designed according to the chemical configuration of the bonds between the saccharide units. In a combined pro-cedure, the silica nanowires will be assembled into a nanoscale photonic device using soft lithographic techniques, i.e. capillary force lithography. Advanced techniques will be used to characterise the material (HR-TEM, EDS, AFM, XPS) and optical (ellipsometry, interferome-try, FTIR-microscopy) properties. Potential application of aligned silica nanowires are coher-ent IR-bundles as waveguides for low-loss IR transmission beyond four microns (4 µm).