Falk Schulze-Küppers

Tape Casting as a Multi Purpose Shaping Technology for Different Applications in Energy Issues

Tape casting is widely used in industrial scale for production of multilayer ceramic capacitors or substrates for different applications. In 2009, it was successfully introduced as standard shaping technology for 3 (BSCF) are shown. The entire scope from the preparation of the used powders, the different manufacturing steps and their optimization potential up to the final tape-cast product will be discussed. The influence of the use of pore forming agents, heat treatment or other parameters during processing will be described in detail. Finally, the option of sequential tape casting of different materials for graded structures as a future step in shaping technology will be presented for different applications.

Supported oxygen transport membranes for oxyfuel power plants

In order to improve the oxygen permeation rates of oxygen transport membranes (OTM), asymmetric membranes with a thin dense layer must be fabricated on a porous support. In this paper, we focus on preparing and characterizing structures with functional layers consisting of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) and La0.68Sr0.3Fe0.8Co0.2O3-δ (LSFC). The supports for these structures were prepared by tape casting and warm pressing, and samples were analysed in terms of nitrogen permeability and porosity. The coating of the functional layers was performed via screen printing. For BSCF, multiple layers were necessary to obtain a gas-tight structure. Oxygen permeation measurements of the asymmetric structures showed an increase in the oxygen flux in comparison to bulk membranes with a thickness of L =1 mm. However, this enhancement is subproportional to the reduced thickness, indicating rate limiting effects, i.e. surface exchange kinetics in the case of LSFC and concentration polarization in the porous support in the case of BSCF.

Development of Thin-Film Manufacturing Technologies for Solid Oxide Fuel Cells and Gas Separation Membranes

The development of solid oxide fuel cells (SOFCs) and gas separation membranes for fossil (fuel?) power plants has previously suffered from cost issues like the manufacturing of the core components including i) the ceramic fuel cell and ii) the ceramic membrane, and from insufficient power density (current density or flow rate) on the stack, module or system level. Forschungszentrum Julich has been working on SOFC development for 20 years, and on membrane development for 6 years. Both energy-related applications are based on similar materials systems, similar micro-structural features (porous-dense, coarse-fine), comparable application parameters (e.g. high temperature) and are manufactured with similar technologies. In the past the focus laid mostly on basic materials research and proving the functionality of the membranes or fuel cells. Meanwhile, one key topic has been the application of low-cost thin-film high-throughput manufacturing technologies. This includes the fabrication of the supports (mostly...