Evaluation of Er Doped CeO2-δ as Oxygen Transport Membrane

Abstract

Ceria based materials are robust candidates for a range of applications involving redox reactions and high oxygen activity. The substitution of erbium in the ceria lattice introduces extrinsic oxygen vacancies. Further addition of Co introduces electronic carriers. We have studied the structural and redox behavior of Ce1−xErxO2-δ (x = 0.1 and 0.2) and the influence of adding 2 mol% of Co in the electrochemical properties. A limitation in the solubility of Er cation is found. Diffusion and surface exchange coefficients have been obtained by electrical conductivity relaxation and the DC-conductivity and O2 permeation measurements show the importance of the electronic component in the transport properties, obtaining an oxygen permeation flux of 0.07 mL·min−1·cm−2 at 1000 °C, for a 769 μm thick membrane.

The Relationship between Photoluminescence Emissions and Photocatalytic Activity of CeO2 Nanocrystals

“…Cerium dioxide (CeO 2 ), or ceria, is one of the most reactive rare earth oxides. It shows excellent properties needed for fabricating resonators, antennas, and filters, such as low dielectric loss and improved Q × f property associated with relatively high dielectric constant values (ε ≈ 29.41), and wide theoretical bandgap energy ( E gap = 6.0 eV). − Due to its unique combination of properties, CeO 2 stands out as an important multifunctional material with applications as gas sensors, , oxygen permeation membranes, , catalysts, solar cells, − coatings, − and biomedicine. , Its characteristic optical absorption edge associated with its broadband photoluminescent (PL) emission in the visible region and ferromagnetic activity, observed in nanostructured CeO 2 , also make it suitable for optoelectronics , and spintronics applications.…”