Temperature-Dependent Delocalization of Oxygen Vacancies in La-Substituted CeO2

Signature of oxygen ion conductivity in hydro-thermally synthesized Ce(1-x)LaxO(2-delta )(0 & LE; x & LE; 0.50) solid-electrolyte samples has been investigated. Room-temperature Raman spectroscopy clearly shows the presence of intrinsic and extrinsic defect modes related to oxygen vacancies. Evidence of delocalization of oxygen vacancies has been analyzed through the combination of temperature-dependent Raman spectroscopy and optical absorption spectroscopy for the first time in these solid ionic conductors. Therefore, the temperature-dependent softening of oxygen defect mode in Raman spectroscopy and broadening of a feature related to oxygen defectsin optica l absorption spectroscopy can be an efficient tool to probe the signature of oxygen ion conductivity.

Automated summary

The signature of oxygen ion conductivity in hydro-thermally synthesized Ce(1-x)LaxO(2-delta)(0 ≤ x ≤ 0.50) solid-electrolyte samples has been investigated. The temperature-dependent softening of oxygen defect mode in Raman spectroscopy and broadening of a feature related to oxygen defects in optical absorption spectroscopy can be efficient tools to probe the signature of oxygen ion conductivity.