2 research outputs found
Mixed proton and electron conducting double perovskite anodes for stable and efficient tubular proton ceramic electrolysers.
[EN] Hydrogen production from water electrolysis is a key enabling energy storage technology for the large-scale deployment of intermittent renewable energy sources. Proton ceramic electrolysers (PCEs) can produce dry pressurized hydrogen directly from steam, avoiding major parts of cost-driving downstream separation and compression. However, the development of PCEs has suffered from limited electrical efficiency due to electronic leakage and poor electrode kinetics. Here, we present the first fully operational BaZrO3-based tubular PCE, with 10 cm(2) active area and a hydrogen production rate above 15 Nml min(-1). The novel steam anode Ba1-xGd0.8La0.2+xCo2O6-delta exhibits mixed p-type electronic and protonic conduction and low activation energy for water splitting, enabling total polarization resistances below 1 Omega cm(2) at 600 degrees C and Faradaic efficiencies close to 100% at high steam pressures. These tubular PCEs are mechanically robust, tolerate high pressures, allow improved process integration and offer scale-up modularity.The work leading to these results has received funding from the Research Council of Norway (grant 236828) and from the European Union's Seventh Framework Programme (FP7/2007-2013) for the Fuel Cells and Hydrogen Joint Technology Initiative under grant agreement 621244 ('ELECTRA') and Fuel Cells and Hydrogen 2 Joint Undertaking under grant agreement 779486 ('GAMER'). This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation programme, Hydrogen Europe and Hydrogen Europe research.Vøllestad, E.; Strandbakke, R.; Tarach, M.; Catalán-MartĂnez, D.; Fontaine, M.; Beeaff, D.; Clark, DR.... (2019). Mixed proton and electron conducting double perovskite anodes for stable and efficient tubular proton ceramic electrolysers. Nature Materials. 18(7):752-759. https://doi.org/10.1038/s41563-019-0388-2S75275918
Rheological Behavior of Coextruded Multilayer Architectures
Utilizing a thermoplastic extrusion process, a multilayered architecture was fabricated. Thermoplastic blends of 55 vol% X7R dielectric and 50 vol% nickel powder were prepared by high shear mixing. Sheets pressed from this material were cut, stacked, and laminated to produce multilayered blocks. The blocks were extruded through a slotted spinneret to reduce layer thickness. The relation between viscosity and shear rate is relatively well understood for two- or three-layered polymer coextrusion. This behavior has not been studied for heavily loaded multi-component systems, such as might be used for MLCCs and other multilayered devices. A correlation was observed between the flow behavior during extrusion and that observed during mixing. Results show how control of the rheological behavior of highly loaded systems can control extrusion defects