Site-selective spectroscopy of Eu³⁺ in YSZ and Y³⁺-doped CeO₂

The site-selective spectroscopy has been applied on YSZ and Y³⁺-doped CeO₂ system, which are typical oxygen ion conductor. Small amount of Eu³⁺ ions are introduced into these materials as optically active centers. It is found that there are three different sites for Eu³⁺ ions in YSZ, where the site symmetry is much lower than C_2v. The luminescence spectra observed under site-selective excitation are quite similar to those observed in glass materials. In Y³⁺-doped CeO₂ system, luminescence bands from three different sites of Eu³⁺ ions are observed by the site-selective spectroscopy. One of these bands is attributed to the luminescence from Eu³⁺ ions at O_h symmetry site.