Influence of Tungsten Doping in La2Mo2O9 Oxide-Ion Conductors by Dielectric Relaxation Measurements
The effects of tungsten doping in La2Mo2–yWyO9 (y =0, 0.25, 0.5, 1.0, 1.4) samples were studied using dielectric relaxation measurements. The results indicate that the solubility of W6+ in La2Mo2O9 sample is about 25mol%, W6+ can suppress the α/β phase transition in the La2Mo2O9. Additional to the low-temperature relaxation peak Pd associated with oxygen ion diffusion, a new dielectric loss peak Ph associated with a phase transition from the static disordered state to the dynamic disordered state of oxygen ion distribution was observed around 740 K. The conductivity of La2Mo1.9W0.1O9 sample is higher than that of the pure La2Mo2O9, and then decrease with the increasing of the tungsten doping in La2Mo2–yWyO9 (y = 0.5, 1.0) samples in the whole measurement temperature.
D. Li and X. H. Li, "Influence of Tungsten Doping in La2Mo2O9 Oxide-Ion Conductors by Dielectric Relaxation Measurements", Applied Mechanics and Materials, Vols. 130-134, pp. 3302-3305, 2012