Effect of post-annealing in air on optical and XPS spectra of Y2O3 ceramics doped with CeO2

Yttrium oxide ceramics doped with CeO2 (5 mol%) were prepared from nanopowders produced by the laser ablation method. The optical measurements have demonstrated that the transparency of as-sintered ceramic was markedly increased after annealing (T = 1400 °C) under air. XPS data revealed the presence of mixed Ce3+ and Ce4+ states, while oxygen defect peak decreased after annealing owing to the defect elimination during oxygen diffusion into the highly defective ceramic.