Martin Bram

Preparation of Thin Functional Layers for Anode Supported SOFC by Roll Coating Process

A new method for the application of functional layers for solid oxide fuel cells was tested. So-called “roll coating” is a promising process for an industrial production of SOFCs, because it allows a high degree of automation. Nickel/yttria-stabilized zirconia (Ni/YSZ), YSZ, YSZ-LSM, and La0.65Sr0.3MnO3-δ (LSM) were used as materials for the anode, anode functional layer, electrolyte, cathode and current collector. The anode substrates were produced by tape casting. The anode and electrolyte were subsequently applied by roll coating on unsintered green tapes as well as presintered substrates. After co-sintering at 1400°C for 5h, half-cells with an electrolyte thickness of 10 µm were obtained. Finally, an LSM/YSZ cathode functional layer and an LSM current collector were deposited by screen printing and co-sintered at 1100°C for 3 h. The cells had current densities of 1.0 A/cm 2 at 800°C and 0.7 V, which is lower than the performance of screen-printed Julich standard cells with the same type of LSM/YSZ cathode. It is expected that the performance of roll-coated cells can be improved by further reducing the thickness of the functional layers. The results show that the anode-supported planar half-cells can be fabricated in a cost-effective way by combining roll coating with subsequent co-firing.

Influence of coal power plant exhaust gas on the structure and performance of ceramic nanostructured gas separation membranes

C wiring into nanoscale holes with high aspect ratio by electrodeposition is an important problem for 3-D integration in integrated circuit technology toward miniaturization of electronic devices. However, void and pinhole found in Cu wiring for the integration can cause trouble for miniature device. Cu electroplating method without void and pinhole is needed. We have proposed novel electroplating methods with supercritical carbon dioxide (sc-CO2) emulsion (EP-SCE). The electrochemical reaction is carried out in an emulsion of sc-CO2 in electrolyte with surfactants. Sc-CO2 has low viscosity and compatibility of hydrogen. Thus, this method is applicable in fine Cu wiring. The aim of this report is to examine Cu electrodeposition by using sc-CO2 emulsified electrolyte into nano-scale Cu wiring on the viewpoints of dissolution of Cu seed layer, gap-filling capability into nano-scale holes and contamination in the plated Cu. Moreover a continuous-flow reaction system is proposed and examined for filling of Cu into holes with 60 nm in diameter and aspect ratio of 2 and 5 by EP-SCE on a round-type large-area hole test element group with diameter of 300 mm, which has an integrated structure of Cu seed layer on TiN barrier layer sputtered on Si substrates.T spectroscopy has gained popularity as a promising non-invasive investigation tool in recent decades. In studies of solid-state pharmaceuticals, its usefulness is enhanced, since it enables one to distinguish diff erent polymorphic and pseudo-polymorphic forms. Terahertz absorption spectra are additive, meaning that the resulting spectrum of two or more compounds in the sample is an algebraic sum, in the linear region of the Beer’s law. For this reason, the evolving-in-time linear mixture of unknown pure components can be resolved using the blind source separation approach, where both spectral sources and their concentrations are to be estimated. Such an evolution occurs naturally in temperature-induced (pseudo) polymorphic transitions, i.e. dehydration, where the terahertz spectrum is the hydrate and dehydrates’s response with timevarying proportions. Conventionally, to estimate the kinetics of a reaction–an important physical-chemical parameter–the area of the unique spectral peak is integrated and normalized to evaluate the abundance, but a diffi culty of strongly overlapping peaks unable its application. To overcome this problem, we show, that by employing the blind source separation procedure, we can resolve a complex, multi-compound spectral mixture with signifi cant cross-bands, where the peak area method failed. We evaluate the performance of our approach in studies on dehydration of a well-known polycrystalline hydrate–α-D-glucose monohydrate. Seeing that the polymorphic transitions can completely change the properties of a pharmaceutical, our approach can fi nd application in a drug development process, where their careful characterization is of utmost importance.