Nouveau papier de Monica Burriel
Le papier "Rational design of hierarchically nanostructured electrodes for solid oxide fuel cells" a été publié dans Journal of Power Sources
Ici vous trovuerez le papier de Monica Burriel
"Understanding, controlling and optimizing the mechanisms of electrode reactions need to be addressed for high performance energy and storage conversion devices. Hierarchically structured porous films of mixed ionic electronic conductors (MIECs) and their composites with ionic conductors offer unique properties. However, correlating the intrinsic properties of electrode components to microstructural
features remains a challenging task. Here, La0.6Sr0.4Co0.2Fe0.8O3d (LSCF) and La0.6Sr0.4Co0.2Fe0.8O3d:Ce0.9Gd0.1O2-d (LSCF:CGO) composite cathodes with hierarchical porosity from nano to micr range are fabricated. The LSCF film exhibits exceptional electrode performance with area specific resistance values of 0.021 and 0.065 U cm2 at 650 and 600 °C respectively, whereas LSCF:CGO composite is only slightly superior than pure LSCF below 450 °C. We report for the first time a numerical 3D Finite Element Model (FEM) comprising real micro/nanostructural parameters from 3D reconstructions into a simple geometry similar to experimentally observed columnar features. The model demonstrates that heterogeneities in porosity within the film thickness and percolation of the ionically conducting phase significantly impact bulk transport at low temperatures. Design guidelines relating performance to microstructure and bulk material properties in relation to experimental results are proposed. Our model has potential to be extended for rational design of larger, regular and heterogeneous microstructures. "
"Understanding, controlling and optimizing the mechanisms of electrode reactions need to be addressed for high performance energy and storage conversion devices. Hierarchically structured porous films of mixed ionic electronic conductors (MIECs) and their composites with ionic conductors offer unique properties. However, correlating the intrinsic properties of electrode components to microstructural
features remains a challenging task. Here, La0.6Sr0.4Co0.2Fe0.8O3d (LSCF) and La0.6Sr0.4Co0.2Fe0.8O3d:Ce0.9Gd0.1O2-d (LSCF:CGO) composite cathodes with hierarchical porosity from nano to micr range are fabricated. The LSCF film exhibits exceptional electrode performance with area specific resistance values of 0.021 and 0.065 U cm2 at 650 and 600 °C respectively, whereas LSCF:CGO composite is only slightly superior than pure LSCF below 450 °C. We report for the first time a numerical 3D Finite Element Model (FEM) comprising real micro/nanostructural parameters from 3D reconstructions into a simple geometry similar to experimentally observed columnar features. The model demonstrates that heterogeneities in porosity within the film thickness and percolation of the ionically conducting phase significantly impact bulk transport at low temperatures. Design guidelines relating performance to microstructure and bulk material properties in relation to experimental results are proposed. Our model has potential to be extended for rational design of larger, regular and heterogeneous microstructures. "