Effects of LiF addition on microstructure and dielectric properties of CaCu3Ti4O12 ceramics

Autor(es)

Porfirio, T. C. ^[1] ; Muccillo, E. N. S. ^[1]

Afiliação do(s) autor(es)

^[1] Energy & Nucl Res Inst IPEN, POB 11049, BR-05422970 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CERAMICS INTERNATIONAL; v. 42, n. 10, p. 12005-12009, AUG 1 2016.
• Citações Web of Science: 5

Resumo

The effects of small amounts of lithium fluoride sintering aid on the microstructure and dielectric properties of CaCu3Ti4O12 (CCTO) ceramics were investigated. CCTO polycrystalline ceramics with 0.5 and 1.0 mol% LiF, and without additive were prepared by solid state synthesis. Good densification (>90% of the theoretical density) was obtained for all prepared materials. Specimens without the sintering aid and sintered at 1090 degrees C exhibit secondary phases as an outcome of the decomposition reaction. The mean grain size is controlled by the amount of LiF in specimens containing the additive. Impedance spectroscopy measurements on CaCu3Ti4O12 ceramics evidence the electrically heterogeneous nature of this material consisting of semiconductor grains along with insulating grain boundaries. The activation energy for grain boundary conduction is lower for specimens prepared with the additive, and the electric permittivity reached 53,000 for 0.5 mol% LiF containing CCTO. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved. (AU)

• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs