Publications by authors named "J Manuel Porras-Vazquez"

Rare-earth doped CeO materials find extensive application in high-temperature energy conversion devices such as solid oxide fuel cells and electrolyzers. However, understanding the complex relationship between structural and electrical properties, particularly concerning rare-earth ionic size and content, remains a subject of ongoing debate, with conflicting published results. In this study, we have conducted comprehensive long-range and local order structural characterization of CeLnO samples ( ≤ 0.

View Article and Find Full Text PDF

Free-standing films have been obtained by drop-casting cellulose-glycerol mixtures (up to 50 wt% glycerol) dissolved in trifluoroacetic acid and trifluoroacetic anhydride (TFA:TFAA, 2:1, v:v). A comprehensive examination of the optical, structural, mechanical, thermal, hydrodynamic, barrier, migration, greaseproof, and biodegradation characteristics of the films was conducted. The resulting cellulose-glycerol blends exhibited an amorphous molecular structure and a reinforced H-bond network, as evidenced by X-ray diffraction analysis and infrared spectroscopy, respectively.

View Article and Find Full Text PDF

Symmetrical solid oxide cells (SSOCs) have recently gained significant attention for their potential in energy conversion due to their simplified cell configuration, cost-effectiveness, and excellent reversibility. However, previous research efforts have mainly focused on improving the electrode performance of perovskite-type electrodes through different doping strategies, neglecting microstructural optimization. This work presents novel approaches for the nanostructural tailoring of (LaSr)FeTiO (LSFT, = 0.

View Article and Find Full Text PDF

LaCrMnO-CeGdO (LCM-CGO) nanocomposite layers with different LCM contents, between 40 and 60 wt %, are prepared in a single step by a spray-pyrolysis deposition method and evaluated as both air and fuel electrodes for solid oxide fuel cells (SOFCs). The formation of fluorite (CGO) and perovskite (LCM) phases in the nanocomposite electrode is confirmed by different structural and microstructural techniques. The intimate mixture of LCM and CGO phases inhibits the grain growth, retaining the nanoscale microstructure even after annealing at 1000 °C with a grain size lower than 50 nm for LCM-CGO compared to 200 nm for pure LCM.

View Article and Find Full Text PDF