Fabrication and characterization of functional nanowire and tube based devices

最近，我们发现在金属蒸发后，过渡金属二卤化物(TMDCs)的平面上会自组织成厘米尺度的纳米线(8 Nm)的延伸网络。初步结果表明，现在可以用类似的方法在绝缘聚合物衬底上获得金属纳米线。通过在聚合物表面使用不同的附着系数，在预应变的衬底上通过传统的CVD工艺制备，连续的和“虚线”形式的纳米线。此外，它们可以在各种几何形状中以极高的精度对齐，范围从单根隔离导线到平行和垂直交叉网络的阵列。除了在厘米大小的衬底上进行高控制量和快速生产之外，这些新型纳米线的另一个优势是它们在表面形成。由于这些纳米线只是部分嵌入，导线的一侧由衬底表面机械支撑，而另一侧易于接触，不仅用于功能化和直接应用，如气敏元件，而且还能够进一步的三维结构。最后，我们发现聚合物银纹中的金属化纤维导致了金属纳米管的良好连接。我们建议系统地研究这种用于生产纳米线和纳米管的新方法。我们打算探索哪些材料组合能够产生这些排列的纳米结构的最佳条件，并找到最适合应用的组合。这可以通过了解材料特性方面的潜在生长机制的细节来实现，包括所应用的聚合物材料的扩散长度、粘着系数或薄膜特性。基尔大学多组分材料教席在金属-聚合物界面以及纳米线研究领域拥有长期的专业知识。由于这个项目进一步研究了用技术上相关的材料控制纳米线的合成，我们相信我们的新方法可以为Schwerpenkt计划的进展做出重大贡献：“Nanodrähte und Nanoröhren：von kontrollierter Synthes zur Funktion”。

Recently, we have discovered that extended networks (cm-scale) of nanowires (as small as 8nm) self-organize on the flat surfaces of transition metal dichalcogenides (TMDCs) after metal evaporation. The preliminary results show that it is now possible to obtain, with a similar approach, metal nanowires on insulating polymer substrates. Fabricated by a conventional CVD process on pre-strained substrates by using different sticking coefficients on polymer surfaces, continuous as well as "dashed" nanowires form. Furthermore, they can be aligned with excellent precision in various geometries, ranging from single isolated wires to arrays of parallel and perpendicular intersecting networks. A further advantage of these new class of nanowires, other than the high amount of control and a rapid production on cm-sized substrates, is that they form on the surface. Because theses nanowires are only partially em-bedded, one side of the wire is mechanically supported by the substrate surface, while the other side is readily accessible, not only for functionalization and direct applications such as gas sen-sors but also to enable further three-dimensional structuring. Lastly, we have discovered that the metallization fibrils in polymer crazes lead to well-connected metal nanotubes. We propose to study systematically this novel approach for the production of nanowires and nanotubes. We intent to explore which material combinations allow the best conditions to generate these aligned nanostructures and find the combinations best suitable for applications. This can be done by understanding the details of the underlying growth mechanisms in terms of material properties including diffusion length, sticking coefficients, or thin film features of the applied polymer materials. The Chair for Muticomponent Materials at the University of Kiel has long-standing expertise in the field of metal-polymer interfaces and as well as in nanowire research. Since this project further investigates the controlled syntheses of nanowires with technologi-cally relevant materials, we believe that our new approach can contribute significantly to the progress in the Schwerpunktprogramm: "Nanodrähte und Nanoröhren: von kontrollierter Synthese zur Funktion".