Designing of nanoparticle morphology in aerosol synthesis

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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