Optical and electrical characterization of samaria-doped ceria

• Published in: Journal of alloys and compounds 2010-02, Vol.491 (1), p.460-464
• Main Authors: Souza, E.C.C., Brito, H.F., Muccillo, E.N.S.
• Format: Article
• Language: English
• Subjects: Chemical synthesis; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Diffusion in solids; Exact sciences and technology; Impedance spectroscopy; Materials science; Nanocrystals and nanoparticles; Nanopowders; Nanoscale materials and structures: fabrication and characterization; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Oxides; Photoluminescence; Physics; Raman spectroscopy; Self-diffusion and ionic conduction in nonmetals; Transport properties of condensed matter (nonelectronic)
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2009.10.226

Ce 0.8Sm 0.2O 1.9 and CeO 2 nanomaterials were prepared by a solution technique to produce an ultrafine particulate material with high sinterability. In this work, the structural characteristics, the photoluminescent behavior and the ionic conductivity of the synthesized materials are focused. The thermally decomposed material consists of less than 10 nm in diameter nanoparticles. The Raman spectrum of pure CeO 2 consists of a single triple degenerate F 2g model characteristic of the fluorite-like structure. The full width at half maximum of this band decreases linearly with increasing calcination temperature. The photoluminescence spectra show a broadened emission band assigned to the ligand-to-metal charge-transfer states O → Ce 4+. The emission spectra of the Ce 0.8Sm 0.2O 1.9 specimens present narrow bands arising from the 4G 5/2 → 6H J transitions ( J = 5/2, 7/2, 9/2 and 11/2) of Sm 3+ ion due to the efficient energy transfer from the O → Ce 4+ transitions to the emitter 4G 5/2 level. The ionic conductivity of sintered specimens shows a significant dependence on density.