Nanoscale Methods for Manipulation and Characterization of Aerosol Chain Aggregates

摘要本课题的目标是开发纳米尺度的方法来操纵纳米颗粒链聚集体（NCA）并测量其性质。这些聚集体表现出弹性特性，已经在5到10纳米尺寸范围内的颗粒组成的几种金属氧化物中观察到。粒子间键能的测量和弹性的表征是我们感兴趣的，互补的理论工作将根据粒子键的基本性质来解释测量结果。对聚合体的系统研究将促进基本认识，并具有广泛的技术意义。拟议的研究包括四个方面。将设计一种用于NCA合成的改进激光烧蚀发生器，以生产更多的单分散颗粒。原子力显微镜将测量NCAs的键能和弹性性能。NCA拉伸的高速视频分析将用于表征弹性性能。理论研究将测量的NCA性能与主要粒度和材料性能联系起来。相关的实验和理论方法包括重构、晶界滑动和范德华力的统计模型。该模型具有定量预测的潜力。这项工作有可能应用于改善由纳米颗粒制成的材料的性能，包括填充橡胶和陶瓷。

AbstractThe goal of this proposal is to develop nanoscale methods to manipulate nanoparticle chain aggregates (NCA) and measure their properties. These aggregates exhibit elastic properties, which have been observed for several metal oxides composed of particles in the 5 to 10 nm size range. Measurement of the bond energies between particles and characterization of the elasticity are of interest, and complementary theoretical work will interpret the measurements in terms of fundamental properties of particle bonds. A systematic investigation of aggregates would advance fundamental understanding and have broad technological implications. The proposed research covers four areas. An improved laser ablation generator for NCA synthesis will be designed to permit the production of more monodisperse particles. Bond energies and elastic properties of the NCAs will be measured by atomic force microscopy. High-speed video analysis of NCA stretching will be used to characterize elastic properties. Theoretical studies will relate measured NCA properties to primary particle size and material properties. Methods of relating experiment and theory include a statistical model of restructuring, grain boundary sliding, and van der Waals forces. The model has the potential for quantitative predictions. This work has the potential for application to improving the performance of materials produced from nanoparticles including filled rubber and ceramics.