Different layered perovskite-related oxides are known to exhibit important electronic, magnetic and electrochemical properties. Owing to their excellent mixed-ionic and electronic conductivity and fast oxygen kinetics, cation layered double perovskite oxides such as PrBaCo2O5 in particular have exhibited excellent properties as solid oxide fuel cell oxygen electrodes. Here, we show for the first time that related layered materials can be used as high-performance fuel electrodes. Good redox stability with tolerance to coking and sulphur contamination from hydrocarbon fuels is demonstrated for the layered perovskite anode PrBaMn2O5+δ (PBMO). The PBMO anode is fabricated by in situ annealing of Pr0.5Ba0.5MnO3-δ in fuel conditions and actual fuel cell operation is demonstrated. At 800 °C, layered PBMO shows high electrical conductivity of 8.16 S cm(-1) in 5% H2 and demonstrates peak power densities of 1.7 and 1.3 W cm(-2) at 850 °C using humidified hydrogen and propane fuels, respectively.

Solid oxide fuel cells (SOFC) are the cleanest, most efficient, and cost-effective option for direct conversion to electricity of a wide variety of fuels. While significant progress has been made in anode materials with enhanced tolerance to coking and contaminant poisoning, cathodic polarization still contributes considerably to energy loss, more so at lower operating temperatures. Here we report a synergistic effect of co-doping in a cation-ordered double-perovskite material, PrBa0.5Sr0.5Co2−xFexO5+δ, which has created pore channels that dramatically enhance oxygen ion diffusion and surface oxygen exchange while maintaining excellent compatibility and stability under operating conditions. Test cells based on these cathode materials demonstrate peak power densities ~2.2 W cm−2 at 600°C, representing an important step toward commercially viable SOFC technologies.

Solid oxide fuel cells (SOFCs) are characterized by low pollution, and are therefore the best alternative both for distributed energy sources and large‐scale integration. Fuel flexibility, including hydrocarbons, is the main advantage of SOFCs. For the successful introduction of SOFC technology to the market, reduced temperature operation at 600–800 °C is an essential factor. One of the important issues for the reduced temperature operation is to get rid of stability issues while maintaining a certain level of performance. Therefore, the development of alternative materials such as perovskite cathodes is essential to create not only practically acceptable performance, but also to ensure the highly reliable and stable operation of the resulting SOFCs. This review provides a critical and comprehensive survey on the perovskite materials for SOFC cathodes and suggests effective and stable alternatives for the realiable operation of SOFCs.

A class of double-perovskite compounds display fast oxygen ion diffusion and high catalytic activity toward oxygen reduction while maintaining excellent compatibility with the electrolyte. The astoundingly extended stability of NdBa(1-x)Ca(x)Co2O(5+δ) (NBCaCO) under both air and CO2-containing atmosphere is reported along with excellent electrochemical performance by only Ca doping into the A site of NdBaCo2O(5+δ) (NBCO). The enhanced stability can be ascribed to both the increased electron affinity of mobile oxygen species with Ca, determined through density functional theory calculations and the increased redox stability from the coulometric titration.

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