II Simposio Internacional de Ciencia de los Materiales

Investigation of the dielectric dispersion in (Bi0.5Na0.5)1–xBaxTiO3 lead-free ferroelectric ceramics from the Cole-Cole formalism

No programado

20m

Centro Demostrativo de Energía Renovables (Quinta de los Molinos)

Presentación oral Síntesis y Caracterización de Materiales Materiales para la conversión y almacenamiento de Energía

Ponente

Alejandro Carlos Iglesias Jaime (Grupo de Materiales Ferroicos, Facultad de Física-Instituto de Ciencia y Tecnología de Materiales, Universidad de La Habana, La Habana 10400, Cuba.)

Descripción

(Bi0.5Na0.5)1–xBaxTiO3 lead-free ferroelectric ceramics were synthetized via the conventional solid-state reaction sintering method, considering x = 10, 16, 18 at%. The structural analysis has shown the formation of the perovskite structure with different crystalline symmetries, depending on the BT content: a coexistence of two tetragonal phases (antiferroelectric, P4bm and ferroelectric, P4mm) for x = 10 at% and a single tetragonal ferroelectric phase (P4mm) for x = 16, 18 at%. The dielectric response, performed in wide temperature and frequency ranges, revealed several dielectric anomalies, which have been associated to different phases’ transitions, one of them showing relaxor-like characteristics with significant frequency dispersion. In order to understand the observed dispersion around the first anomaly, a quantitative analysis has been taken into account considering the Cole-Cole formalism.