Fullerene Nano-Probes

这个项目解决了纳米技术的一个重大挑战：学习如何在纳米尺度上对单个物体进行成像和操作。利用富勒烯纳米管和纳米线形式的碳网络，该项目旨在开发新一代探针，以化学特异性和原子精度连接宏观和纳米世界。尽管x射线衍射和相关技术长期以来一直是我们在原子长度尺度上详细了解物体的基础，但它们只适用于排列在规则晶格中的大量相同结构的副本。自从扫描隧道显微镜（STM）的发明和早期应用以来，人们越来越清楚地认识到，至少在原则上，突破这种需要晶体阵列的要求是可能的。在纳米尺度上，一个接一个地对单个结构进行成像、探测和操作应该是可能的。因此，将STM的思想扩展到其他近似探针，如原子力显微镜（AFM）和磁力显微镜（MFM），已成为世界范围内的一项重大科学努力。所有这些方法的共同特点是，它们依赖于宏观和纳米领域之间的直接物理连接，其形式是一个微小的“尖端”，由压电装置以亚埃精度扫描。大多数块状材料在被拉长成宽度小于10纳米的探针时，化学性质不稳定。然而，石墨薄片形式的碳在富勒烯球和富勒烯管形式下的化学性质是稳定的，即使它们的直径小于1纳米。该项目旨在全面发展富勒烯管作为近端探针和操纵器的尖端。富勒烯纳米管将通过目前已知的使用碳弧和/或催化颗粒的技术和目前正在开发的新方法来生产。这些包括在石英管炉中通过激光汽化碳/金属催化剂复合靶来生产单壁和多壁纳米管，以及在高电场中控制安装的“种子晶体”纳米管的生长。将开发安装技术，将单个纳米管连接到具有良好电接触和可靠的机械、化学稳定性的锐化铂电极上。单独安装的纳米管的电气和机械性能将被测量，包括它们在光学频率下作为高效天线的能力，以及用作纳米级悬臂时的Q值。＊＊＊

9522251 Smalley This project addresses one of the grand challenges of nanotechnology: learning how to image and manipulate individual objects on the nanometer scale. Using carbon networks in the form of fullerene nanotubes and wires, this project aims to develop a new generation of probes which connect the macroscopic to the nanoscopic world with chemically specific, atomic precision. Whereas x-ray diffraction and related techniques have long been the basis of our detailed understanding of objects on this atomic length scale, they only work with large numbers of identical copies of the structure arranged in regular crystal lattices. Since the invention and early applications of scanning tunneling microscopy (STM) it has become increasingly clear that it is possible, at least in principle, to break loose from this requirement of needing a crystalline array. It should be possible to image, probe and manipulate individual structures, one by one, on the nanometer scale. Extensions of the idea of STM to other proximate probes such as atomic force microscopy (AFM), and magnetic force microscopy (MFM) have therefore become a major scientific endeavor worldwide. The common feature of all these methods is that they rely on a direct, physical connection between the macroscopic and nanoscopic realms in the form of a tiny "tip" which is scanned with sub-angstrom precision by piezoelectric devices. Most bulk materials are not chemically stable when elongated into probes of width less than 10 nanometers. However, carbon in the form of a graphine sheet is chemically stable in the form of fullerene balls and tubes even when these are less that 1 nm in diameter. This project is aimed at the general development of fullerne tubes as the tips of proximate probes and manipulators. Fullerene nanotubes will be produced both by currently known techniques using carbon arcs and/or catalytic particles and by new methods presently under development. These involve production o f single- and multi-walled nanotubes by laser vaporization of carbon/metal catalyst composite targets in a quartz tube furnace, and controlled growth of mounted "seed crystal" nanotubes in high electric fields. Mounting techniques will be developed to attach individual nanotubes to sharpened platinum electrodes with good electrical contact and reliable mechanical, chemical stability. Electrical and mechanical properties of the individually mounted nanotubes will be measured, including their ability to serve as efficient antennas at optical frequencies and their Q value when used as a nanoscopic cantilever. ***