Room-temperature Synthesis and Conductivity of the Pyrochlore Type Dy2(Ti1-yZry)2O7 (0 < y < 1) Solid Solution
K.J. Moreno; M.A. Guevara-Liceaga; A.F. Fuentes; J. García-Barriocanal; C. León; J. Santamaría. Room-temperature Synthesis and Conductivity of the Pyrochlore Type Dy2(Ti1-yZry)2O7 (0 < y < 1) Solid Solution. Journal of Solid State Chemistry (ISSN: 0022-4596). 2006, Vol. 179, p. 928-2006.
Different compositions in a solid solution of general formula Dy2(Ti1-yZry)2O7, showing high oxygen ion conductivity, have been successfully prepared at room temperature via mechanochemical synthesis. Stoichiometric mixtures of the constituent oxides were dry milled together in a planetary ball mill by using zirconia vials and balls. Chemical changes in the powder mixtures as a function of composition and milling time were followed by X-ray diffraction and revealed that, in all cases and after milling for 19 h, the powder mixtures consisted of a single phase. Electrical properties were measured on sintered pellets as a function of frequency, temperature and zirconium content, revealing an increase in conductivity of more than one order of magnitude for y>0.4, which, as observed in the similar Y2(Ti1-yZry)2O7, has been related with the onset of disordering of the anion sublattice. Despite increasing structural disorder with
increasing Zr content, conductivity remains almost constant for y > 0.6, reaching a maximum value of 5.10-3 for Dy2Zr2O7 at 900 C
Different compositions in a solid solution of general formula Dy2(Ti1-yZry)2O7, showing high oxygen ion conductivity, have been successfully prepared at room temperature via mechanochemical synthesis. Stoichiometric mixtures of the constituent oxides were dry milled together in a planetary ball mill by using zirconia vials and balls. Chemical changes in the powder mixtures as a function of composition and milling time were followed by X-ray diffraction and revealed that, in all cases and after milling for 19 h, the powder mixtures consisted of a single phase. Electrical properties were measured on sintered pellets as a function of frequency, temperature and zirconium content, revealing an increase in conductivity of more than one order of magnitude for y>0.4, which, as observed in the similar Y2(Ti1-yZry)2O7, has been related with the onset of disordering of the anion sublattice. Despite increasing structural disorder with
increasing Zr content, conductivity remains almost constant for y > 0.6, reaching a maximum value of 5.10-3 for Dy2Zr2O7 at 900 C