Characterization of dense lead lanthanum titanate ceramics prepared from powders synthesized by the oxidant peroxo method

Autor(es)

Pinto, Alexandre H. ^[1] ; Souza, Flavio L. ^[2] ; Chiquito, Adenilson J. ^[3] ; Longo, Elson ^[4] ; Leite, Edson R. ^[1] ; Camargo, Emerson R. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, UFSCar, Dept Quim, LIEC Lab Interdisciplinar Eletroquim & Ceram, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210170 Santo Andre, SP - Brazil

^[3] Univ Fed Sao Carlos, UFSCar, Dept Fis, BR-13565905 Sao Carlos, SP - Brazil

^[4] Univ Estadual Paulista, UNESP, Inst Quim Araraquara, BR-14801907 Araraquara, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Materials Chemistry and Physics; v. 124, n. 2-3, p. 1051-1056, DEC 1 2010.
• Citações Web of Science: 7

Resumo

Nanosized powders of lead lanthanum titanate (Pb(1-x)La(x)TiO(3)) were synthesized by means of the oxidant-peroxo method (OPM) Lanthanum was added from 5 to 30% in mol through the dissolution of lanthanum oxide in nitric acid followed by the addition of lead nitrate to prepare a solution of lead and lanthanum nitrates which was dripped into an aqueous solution of titanium peroxo complexes forming a reactive amorphous precipitate that could be crystallized by heat treatment Crystallized powders were characterized by FT-Raman spectroscopy and X-ray powder diffraction showing that tetragonal perovskite structure is obtained for samples up to 25% of lanthanum and cubic perovskite for samples with 30% of lanthanum Powders containing 25 and 30% in mol of lanthanum were calcined at 700 degrees C for 2 h and in order to determine the relative dielectric permittivity and the phase transition behaviour from ferroelectric-to-paraelectric ceramic pellets were prepared and sintered at 1100 or 1150 degrees C for 2 h and subjected to electrical characterization It was possible to observe that sample containing 25% in mol of La presented a normal behaviour for the phase transition whereas the sample containing 30% in mol of La presented a diffuse phase transition and relaxor behaviour (C) 2010 Elsevier B V All rights reserved (AU)

• Processo FAPESP: 07/50904-2 - Perovskitas baseadas no titanato de chumbo modificadas com terras raras sintetizadas usando o método dos complexos oxidantes de peróxido (OPM - the oxidant-peroxide method) e caracterizadas com uso complementar de espectroscopia Raman, infravermelho e difração de raios X
• Beneficiário: Alexandre Henrique Pinto
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 07/58891-7 - Perovskitas baseadas no titanato de chumbo modificadas com terras raras sintetizadas usando o método dos complexos oxidantes de peróxido (OPM - the oxidant-peroxide method) e caracterizadas com uso complementar de espectroscopia Raman, difração de raios-X e microscopia eletrônica
• Beneficiário: Emerson Rodrigues de Camargo
• Modalidade de apoio: Auxílio à Pesquisa - Regular