Nanoparticle manipulation with atomic force microscopy techniques - (NANOPARMA)

使用原子力显微镜技术操纵纳米粒子 - (NANOPARMA)

• 批准号: 68809968
• 负责人: Professor Dr. Peter Reimann
• 金额: --
• 依托单位: Arbeitsgruppe Theorie der Kondensierten Materie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/68809968?language=en
• 关键词: Nanoparticle; manipulation; atomic; force; microscopy

Atomic force microscopy (AFM) has proven to be a powerful tool to investigate frictional forces of nanoscale contacts. Unfortunately, this technique reveals some drawbacks when applied to study chemical and structural properties of two rubbing surfaces. The tips used in AFM are prefabricated. Consequently one of the two rubbing surfaces usually consists of a silicon compound and the effective size of the contact will be mainly determined by commercially available tip radii. However, urgent current questions concern the contact area dependence as well as the influence of the material on tribological properties. The contact area dependence of friction is crucial in bridging the gap between nanoscale and microscale friction, which eventually will allow us to understand and control macroscopic friction. The right choice of materials, on the other hand, is expected to lead to new friction effects, like, e.g., superlubricity.A solution of this problem is to use the AFM as a manipulation tool, through the controlled pushing of nanoparticles on the surface. In this case the properties of the surfaces and the nanoparticles can be chosen from a wide range of material combinations. The AFM tip is then used to push the individual particles along predefined pathways, while simultaneously evaluating the frictional forces. Apart from answering long-standing questions regarding fundamental issues in nanoscale tribology, these studies will be able to address issues of controlled motion of the particles for practical applications. In this cooperative research project we propose to investigate these effects systematically, addressing nanoparticles with different sizes, shapes and functional groups on their surfaces, as well as substrates with different roughness, structure and chemical composition in different environments, from liquids to ultrahigh vacuum. The experimental studies are harmonized with theoretical investigations concerning the manipulation process itself, as well as the interfacial atomic processes during particle translation.

原子力显微镜（AFM）已被证明是一个强大的工具，研究纳米级接触的摩擦力。不幸的是，这种技术揭示了一些缺点时，应用于研究两个摩擦表面的化学和结构特性。原子力显微镜中使用的针尖是预制的。因此，两个摩擦表面中的一个通常由硅化合物组成，并且接触的有效尺寸将主要由商业上可获得的尖端半径决定。然而，目前迫切的问题涉及的接触面积的依赖性，以及对摩擦学性能的材料的影响。摩擦的接触面积依赖性对于弥合纳米尺度和微米尺度摩擦之间的差距至关重要，这最终将使我们能够理解和控制宏观摩擦。另一方面，材料的正确选择有望产生新的摩擦效应，例如，该问题的解决方案是使用AFM作为操纵工具，通过控制纳米颗粒在表面上的推动。在这种情况下，表面和纳米颗粒的性质可以从广泛的材料组合中选择。然后使用AFM针尖沿沿着预定义的路径推动单个颗粒，同时评估摩擦力。除了回答长期存在的关于纳米级摩擦学基本问题的问题外，这些研究还将能够解决实际应用中颗粒受控运动的问题。在这个合作研究项目中，我们建议系统地研究这些影响，解决具有不同尺寸，形状和表面官能团的纳米颗粒，以及在不同环境中具有不同粗糙度，结构和化学成分的基底，从液体到真空。实验研究与理论研究相协调，涉及操纵过程本身，以及粒子平移过程中的界面原子过程。