CARES C4T Visiting Scientist Seminar 25th Feb
Event Date: 25 Feb 2016 09:30 AM - 25 Feb 2016 10:30 AM
Event Venue: CREATE Seminar Room (Level 2)
Speaker: Prof. Dr. Christof Schulz
Institute for Combustion and Gas Dynamics – Reactive Fluids (IVG), and
CENIDE, Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Germany
Abstract: Gas-phase synthesis of nanoparticles allows to generate high purity materials with well-controlled properties in continuous flow situations that provide a chance for scale-up to industrial scale. Nanoparticles with well-controlled composition and narrow size distributions are of interest for a wide variety of applications from coatings to electronics to functional materials, e.g., for energy conversion and storage. For the synthesis of materials with desired properties, however, the reaction conditions must be well controlled and the underlying processes understood. The decomposition kinetics of vaporized metal organic compounds, the ignition properties of the mixture of these materials with oxidizing environments as well as the reaction mechanisms of the decomposition, cluster formation and the potential interaction with flame chemistry is a prerequisite for a targeted synthesis of materials. Kinetics experiments are carried out in shock tube reactors with optical and mass spectrometric detection of intermediate and product species, and in flow reactors with laser-based detection of temperature and species concentration. At the same time, reaction conditions such as temperature, intermediate species concentration and particle size must be determined in situ in lab-scale nanoparticle reactors as well as in pilot-plant-scale reactors to provide input and validation data for numerical simulation. In this presentation these aspects will be introduced based chemical kinetics measurements in shock tubes and the investigation of particle formation and growth in flow reactors using molecular-beam sampling and laser based measurements of temperature and intermediate species concentrations.