Praseodymium Doped Ceria: The Role of 4f-Electrons of Pr Dopant in Doped Ceria

Abstract

Oxides like ceria (CeO 2 ) are very promising for solid electrolyte materials when doped by suitable aliovalent dopants, as they introduce high oxygen ion conduction leading to intermediate to low temperature operations (T ≤ 800°C). Over the past decades, engineering new compositions aiming at high ionic conductivity at lower operating temperatures has been a key issue of developing solid oxide fuel cells. However, the understanding of the underlying physics on the oxygen ion conduction in this system remains unclear. In this work, we discuss our DFT+U study on the effect of the 4f-electrons on Pr-doped CeO 2 . We found that, regardless of their localized nature tendency, we found significant contributions from the Pr-dopant 4f-electrons to the oxygen vacancy formation energy as well as the preferential site of the oxygen vacancy formation in comparison with the model of fully localized 4f-electrons, though the geometrical properties for each local minimum structure remain unaffected.

Influence of Zr-doping on the structure and transport properties of rare earth high-entropy oxides

“…Another way to verify the multivalence of Pr is with the help of UV-Vis spectroscopy, as the multivalence of Pr can significantly influence the band gap of these materials [29,30,50]. UV-Vis spectroscopy was performed for these oxides to determine the optical band gap, and the corresponding spectra are presented in figure S9.…”

Extending interstitial tetrelides into carbides: synthesis and crystal and electronic structures- of RE2Co2AlC (RE = La, Pr, Nd)

“…The calculations were performed for both same-spin and spin-polarized setups. ELF (electron localization function), 28,29 and charge density analyses were performed using the Multiwfn 3.8 package. 30 ELF topology was visualized using the VESTA 3.5.8 package.…”

Importance of the Spin–Orbit Interaction for a Consistent Theoretical Description of Small Polarons in Pr-Doped CeO2

“…The relevance of the occupied f-states for the covalent character of Ln-O bonding in lanthanide oxides was pointed out. 39,40 Nevertheless, the reduction from Pr(IV) to Pr(III) was not covered.…”

“…However, Alaydrus et al published a study on Pr­(III)-substituents in CeO 2−δ , investigating the effect of the two f-electrons treated as valence electrons versus core electrons. The relevance of the occupied f-states for the covalent character of Ln-O bonding in lanthanide oxides was pointed out. , Nevertheless, the reduction from Pr­(IV) to Pr­(III) was not covered.…”