Influence of Vanadium on Electrical and Microstructural Properties of CaCu3Ti4O12/CaTiO3

L. A. RAMAJO; R. PARRA; J. A. VARELA; M. M. REBOREDO; M. A. RAMÍREZ; M. S. CASTRO

JOURNAL OF ALLOYS AND COMPOUNDS

ELSEVIER SCIENCE SA

Año: 2010 vol. 497 p. 349 - 353

0925-8388

Microstructure, electrical properties and dielectric behavior of undoped and VO2 - doped CaCu3Ti4O12/CaTiO3 (CCTO/CTO) systems, were investigated. Discs doped with 0 to 3% mol of VO2 were sintered at 1075ºC. CaTiO3 (CTO) was found as a secondary phase in every sample, but vanadium phases were not detected. It was also observed that vanadium diminished the CCTO grain size and dramatically changed the microstructure. The dielectric constant decreased from 13500 to 98000 (at 2500Hz) for undoped to V-doped CCTO/CTO. Also, the breakdown voltage and the non-linear coefficient  increased from 500 to 5000V/m and from 3 to 25, respectively. Energy dispersive X-ray spectroscopy results indicated that vanadium was incorporated in the composite structure.