Hydrogen production from water electrolysis is a key enabling energy storage technology for 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. The development of PCEs has however 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-δ (BGLC) exhibits mixed p-type electronic and protonic conduction and low activation energy for water splitting, enabling total polarization resistances below 1 Ω•cm 2 at 600°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. High temperature electrolysers (HTEs) that utilize readily available steam and/or heat (renewable or industrial) as a supplementary energy source provide superior electrical efficiency compared to conventional water electrolysis. 1-4 HTEs developed to date comprise solid oxide electrolysers (SOEs) which utilize oxide ion conducting electrolytes and therefore produce hydrogen on the steam side cathode. The undiluted high pressure oxygen produced on the anode in SOEs presents a safety hazard. Their high operating temperature (typically 800°C)

The defect chemistry of foreign transition metals in perovskite oxides was investigated by first-principles calculations in combination with experiments with focus on Ni and Zn in Y-doped BaZrO3.

La0.5Ba0.5CoO3−δ–BaZrO3 (LB–BZ)-based composite materials were prepared by a modified Pechini sol–gel method combined with exsolution.

High temperature proton conducting solid oxide fuel cells (PC‐SOFCs) are in a developing state. Electrolytes in these cells should exhibit proton conductivity with essentially no electronic and little other ionic conductivity, as well as long‐term stability in acidic atmospheres. Acceptor substituted rare‐earth ortho‐niobates and ortho‐tantalates were recently demonstrated to exhibit proton conductivity in wet atmospheres, with a maximum of ∼10–3 S cm–1 for 1% Ca‐doped LaNbO4. This modest proton conductivity requires that the electrolyte thickness is in the micron range to reach acceptable PC‐SOFC performances. The long‐term chemical stability and a proton transference number close to unity make these materials highly interesting for high temperature fuel cell applications, in contrast to the more investigated acceptor‐doped BaCeO3 that shows instability towards acidic atmospheres. Here, we describe collaborative efforts between Norwegian partners: SINTEF, Norwegian University of Science and Technology (NTNU) and the University of Oslo for developments towards a fuel cell based on LaNbO4. This comprises identification of materials for the electrodes, interconnect and sealing, optimisation of the microstructures of all cell components, development of shaping processes and design of the fuel cell stack. We address the crucial technological issues of building and testing a PC‐SOFC stack, as well as the comprehensive fundamental understanding of all the processes involved – from fabrication and behaviour of individual components to fabrication of PC‐SOFC fuel cell stacks.