Luminescence of pure yttria

Abstract

Pulsed cathodoluminescence of samples of nominally pure yttria—commercially available powder, nanopowder prepared from it, and ceramics sintered from this nanopowder—is studied in the range 380–850 nm. The luminescence spectra at room temperature exhibit broad bands at λ ≈ 437 and 487 nm and series of narrow bands that are located in the blue (435–510 nm), orange (515–640 nm), red (645–700 nm), and infrared (785–840 nm) spectral ranges. These series are most pronounced in the spectra of commercially available powders. It is assumed that these series are emitted by bound radicals , which are a part of the surface structure of yttria crystals.