Dielectric and non-ohmic analysis of Sr2- influences on CaCu3Ti4O12-based ceramic composites

Author(s)

Cortes, J. A. ^[1] ; Moreno, H. ^[1] ; Orrego, S. ^[1] ; Bezzon, V. D. N. ^[2] ; Ramirez, M. A. ^[1]

Affiliation

^[1] Sao Paulo State Univ UNESP, Fac Engn Guaratingueta, Av Dr Ariberto Pereira Cunha 333, Portal Colinas, BR-12516410 Guaratingueta, SP - Brazil

^[2] Fed Univ ABC UFABC, Ctr Nat & Human Sci CCNH, Av Estados 5001, BR-09210580 Santo Andre, SP - Brazil

• Document type: Journal article
• Source: Materials Research Bulletin; v. 134, FEB 2021.
• Web of Science Citations: 0

Abstract

In this study, CaCu3Ti4O12 ceramic composites were prepared through solid-state reaction by adding Sr2+ and removing Cu2+. Application of the Rietveld method and structure refinement revealed the presence of pure CaCu3Ti4O12 (CCTO) phase for x = 0.00 and Sr0.75Ca0.25TiO3 (SCTO) phase for sample x = 3.00. The other samples presented a mixture of both phases. The sample microstructures showed that increasing the amount of SCTO phase led to the formation of cubic CCTO grains. The x = 0.15 sample presented giant dielectric permittivity results, 3.28 x 10(5), associated with increased grain size and greater grain boundary capacitance, thus indicating it could be a promising material for class III capacitors. On the other hand, greater presence of the SCTO phase displayed potential non-ohmic behavior, as seen with sample x = 2.70, which has a high nonlinear coefficient (alpha similar to 30.0) and low current leakage, (I-L similar to 9.0 mu A). (AU)

• FAPESP's process: 18/18236-4 - Development of advanced CaCu3Ti4O12 ceramics in the form of powders, bulks, and nanostructured films: an integrated studied of its multifunctional properties
• Grantee: Henrique Piccoli Moreno
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)