Designing of nanoparticle morphology in aerosol synthesis

本项目致力于利用前驱体溶液的超声气溶胶喷雾方法和随后的热活性分解来设计纳米粉末合成中的颗粒形貌。如果使用得当，这种反应方法可以得到颗粒大小可控且均匀的产品，允许调节微孔率、表面粗糙度和晶体结构。它们可以特别设计，例如用作催化或烧结活性材料。为了控制所得粉末的颗粒大小或孔隙率等形态特征的一致性，将建立混合热化学动力学模型。该模型将能够解释纳米粒子的形成机制，并用于阐明银的典型工艺窗口。为了进行实验验证，将研究下列参数：银前体的类型和浓度热处理温度和停留时间气溶胶产生的频率由于气溶胶液滴在用于干燥和还原的旧管式反应器中的停留时间只有几秒钟，动力学分析变得非常雄心勃勃，为了进行气溶胶纳米粉末合成中颗粒形态的一般设计配方，将使用以下评估方法：？DTA，TGA和DSC？前体化合物？热化学平衡的因素？用扫描流动粒子仪在线取样显影粉末

This project focuses on the designing of the particle morphology in nanopowder synthesis using the ultrasonic aerosol spray method of a precursor solution and subsequent thermoreactive decomposition. If correctly used, this reaction method results in a product with controlled and uniform particle size, allowing to adjust microporosity, surface roughness and crystal structure. They can be especially designed e.g. for the use as catalytic or sinter-active materials. In order to control a consistency in the morphological characteristics of the obtained powder like particle size or porosity a mixed thermochemical kinetic model will be developed. This model will be capable to explain the formation mechanism of nanosized particles and used to elaborate the process window exemplary for silver. The following parameters will be studied for experimental validation: ¿ type and concentration of silver precursors ¿ thermal treatment temperature and retention time ¿ frequency of aerosol generationAs the residence time of an aerosol droplet in the used tube reactor for drying and reduction amounts only a few seconds, the kinetics analysis gets very ambitious, in order to perform a general design recipe of the particle morphology in aerosol-nanopowder synthesis, the following evaluation methods will be used:¿ DTA, TGA and DSC of precursor compounds¿ FactSage for thermochemical equlibria¿ Inline sampling of developing powders by a Scanning Mobility Particle Sizer ¿ SEM and TEM Analysis