SrCo0.50Fe0.40Ir0.10O3−δ decorated with Pd and La0.8Sr0.2Ga0.83Mg0.17O3−δ: a cleaner electrode for intermediate-temperature solid oxide fuel cells with reduced cobalt content

Recent studies related to cathode materials for solid oxide fuel cells (SOFCs) have showcased the feasibility of stabilizing cubic or tetragonal perovskite phases in the SrCoO3−δ system at room temperature. This achievement has been facilitated by partially substituting Co atoms with small amounts of highly charged cations such as Ir4+ in SrCo0.90Ir0.10O3−δ. This specific material exhibits exceptional performance as a cathode for SOFCs operating at intermediate temperatures (800−850 °C). However, it contains a high amount of cobalt, which is both costly and toxic. In this study, our focus has been on further improving this material by reducing its cobalt content, resulting in a cleaner and more cost-effective cathode for SOFCs. The resulting SrCo0.50Fe0.40Ir0.10O3−δ perovskite, synthesized by the citrate method, introduces a 40% composition of Fe in the sites of Co and Ir, effectively decreasing the amount of Co in the material. The crystal structure of this perovskite oxide has been analyzed using X-ray diffraction (XRD) and neutron powder diffraction (NPD), allowing us to establish correlations with its mechanical and electrical properties. In the single-cell test, this material gave reasonable performances as a cathode at intermediate temperatures (800−850 °C), with La0.8Sr0.2Ga0.83Mg0.17O3−δ (LSGM) as the electrolyte. An analysis of the chemical compatibility between the cathode and the electrolyte, LSGM, demonstrated no interaction at elevated temperatures. Thermal expansion coefficient (TEC) measurements exhibited consistent linear expansion across the entire temperature range. Lastly, the perovskite displayed commendable electrical conductivity along with a promising power density measurement of 384 mW/cm2 at 850 °C. These findings collectively suggest the potential of this material as a viable cleaner cathode option for intermediate-temperature SOFCs. Moreover, the cathode was further optimized and the performance of the cell improved, by either infiltrating SrCo0.50Fe0.40Ir0.10O3−δ with a Pd(NO3)2 solution or mixing it with 30% of LSGM electrolyte, resulting in higher power densities (568 and 675 mW/cm2, respectively) in test cells fed with pure H2 as a fuel.Depto. de Química InorgánicaFac. de Ciencias QuímicasTRUEpu

SrCo0.50Fe0.40Ir0.10O3−δ Decorated with Pd and La0.8Sr0.2Ga0.83Mg0.17O3−δ: A Cleaner Electrode for Intermediate-Temperature Solid Oxide Fuel Cells with Reduced Cobalt Content

Recent studies related to cathode materials for solid oxide fuel cells (SOFCs) have showcased the feasibility of stabilizing cubic or tetragonal perovskite phases in the SrCoO3−δ system at room temperature. This achievement has been facilitated by partially substituting Co atoms with small amounts of highly charged cations such as Ir4+ in SrCo0.90Ir0.10O3−δ. This specific material exhibits exceptional performance as a cathode for SOFCs operating at intermediate temperatures (800–850 °C). However, it contains a high amount of cobalt, which is both costly and toxic. In this study, our focus has been on further improving this material by reducing its cobalt content, resulting in a cleaner and more cost-effective cathode for SOFCs. The resulting SrCo0.50Fe0.40Ir0.10O3−δ perovskite, synthesized by the citrate method, introduces a 40% composition of Fe in the sites of Co and Ir, effectively decreasing the amount of Co in the material. The crystal structure of this perovskite oxide has been analyzed using X-ray diffraction (XRD) and neutron powder diffraction (NPD), allowing us to establish correlations with its mechanical and electrical properties. In the single-cell test, this material gave reasonable performances as a cathode at intermediate temperatures (800–850 °C), with La0.8Sr0.2Ga0.83Mg0.17O3−δ (LSGM) as the electrolyte. An analysis of the chemical compatibility between the cathode and the electrolyte, LSGM, demonstrated no interaction at elevated temperatures. Thermal expansion coefficient (TEC) measurements exhibited consistent linear expansion across the entire temperature range. Lastly, the perovskite displayed commendable electrical conductivity along with a promising power density measurement of 384 mW/cm2 at 850 °C. These findings collectively suggest the potential of this material as a viable cleaner cathode option for intermediate-temperature SOFCs. Moreover, the cathode was further optimized and the performance of the cell improved, by either infiltrating SrCo0.50Fe0.40Ir0.10O3−δ with a Pd(NO3)2 solution or mixing it with 30% of LSGM electrolyte, resulting in higher power densities (568 and 675 mW/cm2, respectively) in test cells fed with pure H2 as a fuel.Depto. de Química InorgánicaFac. de Ciencias QuímicasTRUEpu

Microwave-assisted synthesis of thermoelectric oxides and chalcogenides

The combination of microwaves with other classical synthetic methods may be considered as a powerful tool for the preparation of metal oxides and metal chalcogenides. This approach allows the modification of the reaction kinetic significantly by shortening the processing time to minutes and it minimizes the energy consumption during the synthesis. In this work, potential thermoelectric compounds, which enable the direct conversion of temperature gradients into useful electric energy, have been produced by means of microwave-chemistry routes. Pure phases of SnS1-xSex (x = 0, 0.2, 1) have been synthesized in just 1 min by using microwave-hydrothermal synthesis. Moreover, Zn0.98M0.02O (M = Al, Ga) rods were formed by microwave-coprecipitation method in 5 min. Besides, 8 min of microwave-heating were enough for the combustion of Sr1-xLaxTiO3-δ (x = 0, 0.05, 0.1). In all cases, the utilization of microwave radiation produces high-quality phases. A comprehensive study of the structural, microstructural and thermoelectric properties of the microwave-synthesized materials is here performed by means of X-ray diffraction, SEM, HRTEM and temperature dependence measurements of Seebeck coefficient, electrical conductivity and thermal conductivity.Comunidad de MadridMICINNComunidad de MadridDepto. de Química InorgánicaFac. de Ciencias QuímicasTRUEpu

Nuevos modelos cristalográficos y mineralógicos para impresoras 3D

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasFALSEsubmitte

Diseño de modelos cristalográficos y mineralógicos para impresoras 3D

El proyecto DISEÑO DE MODELOS CRISTALOGRÁFICOS Y MINERALÓGICOS PARA IMPRESORAS 3D es un proyecto de continuación de tres proyectos Innova-Docencia anteriores (nº 5, nº 98 y nº 24) y tenía como finalidad elaborar nuevos modelos cristalográficos y mineralógicos para su impresión mediante impresoras 3D

Modelos bidimensionales y tridimensionales para la enseñanza de la Cristalografía y la Mineralogía

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasFALSEsubmitte