Kinetik und Strukturbildung von komplexen Nanopartikeln in Modellströmungsreaktoren

纳米颗粒可以表现出复杂的结构，如分数壳或结构聚集体，这使得实现新的材料性能和关节性能成为可能。粒子形成和凝聚过程中的基本过程通常很难解释，因为待研究的气溶胶中的纳米粒子在其大小，形式和凝聚结构以及它们的相互作用以及涂层和烧结过程强烈依赖于这些特性方面是相当不同的。同时，以一种明确的方式监控产生的变化和过程是一个巨大的挑战。该项目旨在以更好的定义方式研究这些基本特性，通过尺寸分馏和飞行烧结，以明确的核心颗粒形式提供气溶胶，球形或聚集。然后在流动反应器中启动热重组，这可以是烧结过程，增加初级粒度或涂层过程。应用SMPS、CPMA、DAPS和ELPI等在线测量技术，分析了反应条件和材料体系对反应变化的影响，并借助模型对反应过程进行了分析。将该技术应用于低压反应器，阐明了反应条件对颗粒结构的影响。传统的粒子动力学模型只能描述粒子的体积，不能描述粒子的结构和组成，不能描述粒子的形成结构。因此，蒙特卡罗模拟技术正在被应用，它允许描述粒子和粒子聚集体的多变量特性。该项目的目标是澄清，量化和模拟在气相复杂粒子系统结构过程中发生的过程。将研究与TP3和TP4相关的材料：铁和硅颗粒及其氧化产物。

Nanoparticles can show a complex structure, such score-shell or structured aggregates, which allows to realize novel material properties and joint properties. The fundamental processes during particle formation and agglomeration can oft difficult be interpreted, as the nanoparticles in the aerosol to be investigated are rather different in their size, form and agglomerate structure and their interaction as well as the coating and sintering processes strongly depend on these properties. At the same time, it is a great challenge to monitor the resulting changes and processes in an unambiguous way. This project aims at an investigation of these fundamental properties in a better defined manner, by providing aerosols in form of well-defined core-particles, spherical or aggregated, by means of size-fractionation and in-flight sintering. Then a thermal restructuring is initiated in a flow reactor, this can be sintering process increasing the primary particle size or a coating process. Applying online measurement techniques such as SMPS, CPMA, DAPS und ELPI the resulting changes are analyzed as function of the reaction conditions and materials system, and the processes are analyzed with help of models. This technique is modified and adopted to low-pressure reactors, to clarify the particle structure as function of the reaction conditions. Conventional particle dynamical models are not able to described the formed structures, as they describe only the particle volume and not structure or composition. For that reason, Monte-Carlo simulation techniques are being applied, which allow to described multivariate properties of particles and aggregates of particles. Goal of this project is to clarify, to quantify and to model the processes taking place during the structuring of complex particle systems in the gas phase. Materials will be investigated which have relevance for TP3 and TP4: Fe and Si particles and their oxidation products.