Producción CyT
At the Frontiers of Condensed Matter VII - Study of the electronic and local structure of SrCo1−xMoxO3−δ perovskites (x = 0.05, 0.45, and 0.50) using Synchrotron X-ray Absorption Spectroscopy
Congreso
Autoría:
Arcentales, María Belén ; Esteban Asto Ramos ; Stefania Orozco Gil ; Cristián Huck Iriart ; Diego Germán Lamas ; Santiago FigueroaFecha:
2024Editorial y Lugar de Edición:
FCMResumen *
The growing concern over harmful gas emissions and greenhouse effects has driven the search for sustainable solutions to mitigate environmental impact. In this context, fuel cells have gained significant attention due to their ability to efficiently convert chemical energy into electricity. Solid oxide fuel cells (SOFCs) stand out for their versatility, as they can operate on unpurified hydrogen and various hydrocarbons, including methane and biogas. Currently, research is focusing on intermediate-temperature SOFCs (IT-SOFCs) that function between 500 and 800 °C. To enhance performance at these temperatures, electrode materials with mixed ionic-electronic conductivity are being developed. Additionally, a key area of research is the development of symmetric fuel cells (S-SOFCs), which use identical materials for both the anode and cathode electrodes, thereby simplifying the manufacturing process and reducing costs. The present study evaluates promising materials for S-SOFCs, concentrating on mixed ionic-electronic conductors based on Sr(Co,Mo)O₃₋δ perovskites. The electronic and local structure of SrCo₁₋ₓMoₓO₃₋δ perovskites (with x = 0.05, 0.45, and 0.50) was investigated using advanced techniques such as XANES (X-ray Absorption Near Edge Structure) and EXAFS (Extended X-ray Absorption Fine Structure) at the K edges of Co and Mo. The experiments were conducted in situ under various reducing and oxidizing atmospheres over a temperature range of 20 to 700 °C, allowing for the identification of significant changes in the oxidation state speciation of cations and important modifications in their coordination environments. Additionally, simulations were performed to compare theoretical results with experimental findings, providing a more comprehensive understanding of the observed phenomena. This study expands knowledge about the properties of perovskites under operational conditions and opens new perspectives for their application in fuel cells, contributing to the development of cleaner and more sustainable energy technologies. Información suministrada por el agente en SIGEVAPalabras Clave
perovskitessynchrotronSOFCs