RT Journal Article
T1 Influence of Rare-Earth Doping Content and Type on Phase Transformation and Transport Properties in Highly Doped CeO2
A1 Zamudio-García, Javier
A1 Porras-Vázquez, José Manuel
A1 Cabeza-Díaz, Aurelio
A1 Canales-Vázquez, J.
A1 Ramírez-Losilla, Enrique
A1 Marrero-López, David
K1 Química
K1 Materiales
AB Rare-earth doped CeO2 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 Ce1–xLnxO2–x/2 samples (x ≤ 0.6; Ln = La, Nd, Sm, Gd, and Yb) using X-ray and neutron powder diffraction, Raman spectroscopy, and electron diffraction. The increase in the rare-earth dopant content leads to a progressive phase transformation from a disordered fluorite structure to a C-type ordered superstructure, accompanied by reduced ionic conductivity. Samples with low dopant content (x = 0.2) exhibit higher ionic conductivity in Gd3+ and Sm3+ series due to lower lattice cell distortion. Conversely, highly doped samples (x = 0.6) exhibit superior conductivity for larger rare-earth dopant cations. Thermogravimetric analysis confirms increased water uptake and proton conductivity with increasing dopant concentration, while the electronic conductivity remains relatively unaffected, resulting in reduced ionic transport numbers. These findings offer insights into the relationship between transport properties and defect-induced local distortions in rare-earth doped CeO2, suggesting the potential for developing new functional materials with mixed ionic oxide, proton, and electronic conductivity for high-temperature energy systems.
PB American Chemical Society (ACS)
YR 2024
FD 2024-08-01
LK https://hdl.handle.net/10630/39442
UL https://hdl.handle.net/10630/39442
LA eng
NO ACS Appl. Mater. Interfaces 2024, 16, 32, 42198–42209
NO PID2021–126009OB-I00 funded by MCIN/AEI/10.13039/501100011033
NO Ministerio de Educación, cultura y deporte.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026