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Several core‐shell nanofiber electrodes are prepared through electrospinning and tested for application as intermediate‐temperature solid oxide fuel cell (IT‐SOFC) cathodes. The materials investigated are La0.6Sr0.4MnO3 (LSM), La0.6Sr0.4Cu0.1Mn0.9O3‐δ (LSCuM_1), and La0.6Sr0.4Cu0.2Mn0.8O3‐δ (LSCuM_2) perovskites, used at the shell side of the nanofibers. Ce0.9Gd0.1O1.95 (GDC10) fluorite is used as the core material. The electrochemical characterization of the core‐shell nanofiber electrodes is performed through electrochemical impedance spectroscopy (EIS). The EIS results are reported and discussed based on equivalent circuit modeling. The polarization resistance of the GDC10/LSM core‐shell nanofibers electrodes is RP∼4.5 Ω cm2 at 650 °C. Improvement is accomplished with GDC10/LSCuM_1 and GDC10/LSCuM_2 core‐shell nanofibers, with RP∼1.8 Ω cm2 and 1.7 Ω cm2 respectively at 650 °C. Post‐test SEM characterization is carried out, to ascertain possible degradation and identify the most promising shell perovskite. [ABSTRACT FROM AUTHOR]

In the present work, structural and catalytic characterization was performed on La0.6Sr0.4MnO3 (LSM) nanofibers. The LSM nanofibers were obtained using the electrospinning technique. For comparison, LSM powders with identical composition were characterized as well. The LSM powders were prepared through a self-combustion citrate-based procedure. SEM, EDX, XRD, and BET investigations were carried out on both LSM nanofibers and powders, pointing out the different structural features. The LSM nanofibers showed a higher surface area than the LSM powders and a lower presence of strontium oxide on the surface. Results of the H2-Temperature Programmed Reduction (TPR) tests showed evidence of a higher reactivity of the nanofibers compared to the powders. The catalytic characterization was performed utilizing a methane oxidation activity test, revealing a better catalytic performance of the LSM nanofibers: at 800 °C. The methane conversion achieved with the LSM nanofibers was 73%, which compared well with the 50% obtained with powders at 900 °C. [ABSTRACT FROM AUTHOR]