La0.6Sr0.4Fe0.95Pd0.05O3−δ shows a reversible crystal structure and exhibits improved performance and redox stability when used as electrode in SOFCs.

Tungsten carbide (WC) is the most important tungsten compound, and the main component of WC-Co cermet composites. WC-Co are widely used engineering materials due to the combination of high hardness and strength of tungsten carbide with the toughness and plasticity of the metallic binder. The direct synthesis of WC from tungsten concentrate containing ∼70% WO3 has been achieved by carbothermic reduction. Mineral/carbon black mixtures were prepared by planetary ball milling and subjected to annealing at 1150 °C in flowing Ar. Specific leaching treatments have been developed to remove foreign phases and obtain pure WC powders. This new process allows about 50% energy saving, −34% CO2 emissions, and significantly lower amounts of industrial waste, with respect to the classical hydrometallurgical tungsten extraction and subsequent pyrometallurgical WC synthesis, widely used in tungsten industry. WC powders obtained by carbothermic reduction of the mineral were employed to prepare sintered WC-8 wt %Co samples that showed high density (>99%), hardness (1490 HV), and toughness (14.6 MPa·m1/2). These findings demonstrate, for the first time, that the carbothermic reduction of tungsten concentrates does represent a viable process for energy efficient and sustainable synthesis of WC powders to be used in the production of cemented carbides.

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Structural and microstructural investigations of Pd-doped lanthanum strontium ferrite with stoichiometry La0.6Sr0.4Fe0.9Pd0.1O3-δ (LSFPd) were carried out under oxidizing and reducing conditions. LSFPd exhibited a smart behavior with a reversible redox structural transformation occurring upon switching from air to hydrogen and then back to air. Exsolution of nanometric metal particles was observed after reduction, and re-incorporation of metal cations onto the perovskite structure was confirmed after re-oxidation. The electrochemical performances were evaluated on electrolyte supported cells using LSFPd as symmetric electrodes and La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) as electrolyte. Fuel cell tests revealed promising performance in H2.