Effects of Cu stoichiometry on the microstructure, electrical conduction, and dielectric responses of Y2/3Cu3Ti4O12. Issue 9 (November 2015)

• Record Type: Journal Article
• Authors: Liang, Pengfei; Li, Fuchao; Chao, Xiaolian; Yang, Zupei
• Is Part Of: Ceramics international. Volume 41:Issue 9(2015)Part A
• Page Start: 11314
• Page End: 11322
• Publication Date: 2015-11
• Subjects: B. Grain boundaries -- C. Dielectric properties -- C. Electrical conductivity -- C. Impedance; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.05.089
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: The effects of Cu concentration on the microstructure, electric and dielectric properties of Y2/3 Cu3+ x Ti4 O12 ceramics (−0.10≤ x ≤0.10) were investigated in detail. Appropriate excess in Cu amount would improve the grain growth and give rise to a significant decrease in the low-frequency dielectric loss. The dielectric relaxation behaviors correlated with grain boundary response was obviously intensified by increasing the Cu content. When x ≥0.10, the activation energies for the conduction in grain boundaries were substantially enhanced. The nonlinear I – V behavior further evidenced that the grain boundary resistance could be successfully modified by tuning the Cu amount. The enhanced grain boundary resistance should be responsible for the lowered low-frequency dielectric loss, the increased activation energies for the conduction and the improved nonlinear I – V behavior. Furthermore, the enhanced grain boundary resistance might be attributed to the segregation of Cu-rich phase at grain boundary which had been evidenced by EDX results.