Cathodoluminescence and Raman Spectroscopic Analyses of Nd- or Yb-Doped Y2O3 Transparent Ceramics

In this article, we discuss a study of the influence of Nd3+ and Yb3+ dopants on the spectroscopic behavior of Y2O3 ceramic polycrystals, by using Raman and cathodoluminescence (CL) spectroscopy. Doping with Yb at 1 at % results in a blue shift of the Raman band but has no pronounced influence on the intrinsic emission of Y2O3, while doping with Nd shows a red shift of the Raman band and markedly enhances the oxygen vacancy related 380 nm CL band. Lattice distortion induced by the alien ion incorporation and variations of effective absorption coefficients by adding different dopants were assessed using Raman spectroscopy. Moreover, both CL and Raman spectroscopies were applied to examine the homogeneity and distribution of the dopants throughout the ceramic microstructure. Visualization of sample homogeneity was made available by hyperspectral imaging of the local intensity of CL bands, while spectral deconvolution was performed to retrieve local structural variations at grain boundaries. We also confirmed that the combination of Raman and CL spectroscopies leads to a reliable and useful methodology for the examination of dopants in yttria ceramic materials.