Unit-cell symmetries and Raman spectra of calcium- and neodymium-doped barium cerate proton-conducting ceramic electrolytes
Abstract
Combined X-ray powder diffraction and Raman spectroscopic investigations of the systems BaCe1–xCaxO3–x and BaCe1–xNdxO3–α at ambient temperature are presented. X-Ray studies involving in-depth investigation of diffraction profiles show that the unit cell (a crystal average) is truly orthorhombic throughout the composition ranges of both systems. The Raman spectra for BaCe 1–xCaxO3–α are similar to that for BaCeO3 itself, indicating little distortion of the structure when calcium is dopant. A feature at around 610 cm–1 in the spectra for BaCe1–xNdxO3–α and not evident in the spectra of Ca-doped samples, is associated with modes involving the rare-earth-metal dopant.