RT journal article
T1 Understanding the evolution of ternary alloyed nanoparticles during reversible exsolution from double perovskite oxides
A1 López García, Andrés
A1 Carrillo, Alfonso J.
A1 Jiménez, Catalina Elena
A1 Suarez Anzorena, Rosario
A1 García Diez, Raúl
A1 Pérez Dieste, Virginia
A1 Villar García, Ignacio J.
A1 Hungría Hernández, Ana Belén
A1 Bár, Marcus
A1 Serra, José M.
A2 Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica
AB Multicomponent nanoparticle exsolution has emerged as a promising process for obtaining highly active catalysts supported on perovskite oxides. For instance, FeCoNi alloys can be exsolved from Sr2FeCo0.2Ni0.2Mn0.1Mo0.5O6−d, boosting the electrocatalytic properties of these electrodes. However, due to differences incationdiffusion properties, the composition of the nanoparticles is uneven and strongly affected by process conditions such as temperature. An additional key feature of exsolution is its reversibility, which could help in catalyst regeneration if poisoned. Nevertheless, there is little knowledge on the reversibility mechanisms of multicomponent exsolved alloys. For that purpose, a combination of synchrotron-based in situ X-ray Diffraction (XRD) and Near-Ambient Pressure X-ray Photoelectron Spectroscopy (NAP-XPS) was employed in this work to uncover these missing aspects of multicomponent alloyed exsolution. These techniques allowed determination of the crystallographic and surface-related phenomena occurring during reversible exsolution both to the nanoparticles and the perovskite oxide support. This enabled the identification of the exsolution onset temperature and the range at which the double perovskite to Ruddlesden–Popper transition occurred, a process that has notable implications for the electrocatalytic performance. Finally, in combination with microscopy analyses, it was possible to reveal the morphological and compositional changes that the exsolvednanoparticlesexperiencedupon reductionoxidation cycles. This resulted in a re-arrangement of the surface species and a variation in the composition (Fe enrichment) of the regenerated ternary alloyed exsolved nanoparticles. These results indicate that reversible exsolution might alter the catalytic properties of the exsolved nanoparticles, with profound implications in the performance of (electro)catalytic processes.
PB Royal Society of Chemistry
SN 2050-7496
YR 2024
FD 2024
LK http://hdl.handle.net/10498/35876
UL http://hdl.handle.net/10498/35876
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 13-nov-2026