Nanoscale Methods for Manipulation and Characterization of Aerosol Chain Aggregates

这项提议的目标是发展纳米尺度的方法来操纵纳米粒子链聚集体(NCA)并测量其性质。这些聚集体表现出弹性性质，这已经在几种金属氧化物中观察到，这些氧化物由尺寸在5到10 nm范围内的颗粒组成。测量粒子之间的键能和表征弹性是有意义的，补充的理论工作将从粒子键的基本性质来解释测量。对聚集体的系统调查将促进基本理解，并具有广泛的技术影响。拟议的研究涵盖四个领域。将设计一种用于NCA合成的改进的激光烧蚀发生器，以允许生产更多的单分散粒子。原子力显微镜将测量NCA的键能和弹性性质。将使用NCA拉伸的高速视频分析来表征弹性特性。理论研究将把测量的NCA特性与一次颗粒大小和材料特性联系起来。相关的实验和理论方法包括重排、晶界滑移和范德华力的统计模型。该模型具有进行定量预测的潜力。这项工作有可能应用于改善由纳米颗粒产生的材料的性能，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.