In situ X-ray diffraction studies of phase transition in Pb1-x La x Zr0.40Ti0.60O3 ferroelectric ceramics

Autor(es)

Mesquita, A. ^{[1, 2, 3]} ; Mastelaro, V. R. ^[3] ; Michalowicz, A. ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] CNRS, Inst Chim & Mat Paris Est, F-94320 Thiais - France

^[2] Univ Paris 12, F-94320 Thiais - France

^[3] Univ Sao Paulo, Inst Fis Sao Carlos, BR-05508 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PHASE TRANSITIONS; v. 83, n. 4, p. 251-262, 2010.
• Citações Web of Science: 12

Resumo

The temperature dependence of the crystalline structure and the lattice parameters of Pb1-xLaxZr0.40Ti0.60O3 ferroelectric ceramic system with 0.00 x 0.21 was determined. The samples with x 0.11 show a cubic-to-tetragonal phase transition at the maximum dielectric permittivity, Tmax. Above this amount and especially for the x = 0.12 sample, a spontaneous phase transition from a relaxor ferroelectric state (cubic phase) to a ferroelectric state (tetragonal phase) is observed upon cooling below the Tmax. Unlike what has been reported in other studies, the x = 0.13, 0.14, and 0.15 samples, which present a more pronounced relaxor behavior, also presents a spontaneous normal-to-relaxor transition, indicated by a cubic to tetragonal symmetry below the Tmax. The origin of this anomaly has been associated with an increase in the degree of tetragonality, confirmed by the measurements of the X-ray diffraction patterns. The differential thermal analysis (DSC) measurements also confirm the existence of these phase transitions. (AU)

• Processo FAPESP: 07/00011-1 - Síntese e caracterização estrutural de compostos ferroelétricos relaxores Pb1-xRxZr0,40Ti0,60O3 (R = La, BA)
• Beneficiário: Alexandre Mesquita
• Modalidade de apoio: Bolsas no Brasil - Doutorado