Influence of anionic vacancies on the ionic conductivity of silicated rare earth apatites - Mines Saint-Étienne Access content directly
Journal Articles Materials Research Bulletin Year : 2008

Influence of anionic vacancies on the ionic conductivity of silicated rare earth apatites

Abstract

Oxyapatites are very promising materials in terms of ionic conductivity. They can be considered as a potential electrolyte for Solid Oxide Fuel Cells (SOFC). Doped silicated rare earth apatites with formula La9.33−xCax(SiO4)6O2−x/2 (0 ≤ x ≤ 1) have been prepared by solid state reaction at high temperature in order to determine the influence of anionic vacancies on the electrical properties of the material. The incorporation of calcium in the structure has been checked by characterizations of the powders (X-ray diffraction, helium pycnometry). The cell parameters of the hexagonal apatite were refined. Samples were sintered at 1550 °C. Electrical properties of each composition have been studied between 280 and 620 °C by the complex impedance method. The evolution of the bulk conductivity and of the activation energy with the substituting ratio gives information on the conductivity mechanism in these materials. An improvement of ionic conductivity about one order of magnitude has been observed for low calcium substitution ratios.

Dates and versions

emse-00508434 , version 1 (03-08-2010)

Identifiers

Cite

Pierre Jean Panteix, Emilie Bechade, Isabelle Julien, Pierre Abelard, Didier Bernache-Assollant. Influence of anionic vacancies on the ionic conductivity of silicated rare earth apatites. Materials Research Bulletin, 2008, 43 (5), pp.1223-1231. ⟨10.1016/j.materresbull.2007.05.030⟩. ⟨emse-00508434⟩
202 View
0 Download

Altmetric

Share

Gmail Facebook X LinkedIn More