Premium
Transition of Compensating Defect Mode in Niobium‐Doped Barium Titanate
Author(s) -
Wu TaiBor,
Lin JiuNun
Publication year - 1994
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1994.tb05362.x
Subject(s) - materials science , grain boundary , barium titanate , doping , niobium , condensed matter physics , ferroelectricity , titanium , mineralogy , microstructure , metallurgy , ceramic , optoelectronics , chemistry , dielectric , physics
The influence of Nb‐doping from 1.0 to 8.0 at.% on grain size, ferroelectric phase transition, lattice strain, and electrical properties of BaTiO 3 Cerumics has been studied. A change in the Nb‐doping effect was observed at compositions around 3.5–4.5 at.% Nb. The impedance behavior revealed that specimens of low Nb‐doping had an activation energy of 1.85 eV for carrier conduction either in bulk or at grain boundaries, but specimens having a high Nb‐doping content showed an energy of 1.30 eV in bulk and 1.85 eV at grain boundaries. The capacitance–voltage relation also disclosed different influences of Nb‐doping on the potential barrier height at grain boundaries. The above results are explained by the transition of a compensating defect mode from pure barium vacancies to a combination of titanium vacancies in grain interiors and barium vacancies at grain boundaries as the Nb‐doping content in BaTiO 3 is increased.