Aging effect in acceptor-donor co-doped ferroelectrics

Aging effect exists widely in ferroelectrics, and it is found to be significant only in acceptor-doped ferroelectrics. However, many commercial ferroelectrics contain both acceptor and donor dopants. Thus it is of interest to study aging phenomena in the presence of both acceptor and donor. This paper reports the aging effects in BaTiO₃ with doped B-site acceptor Fe³⁺ and A-site donor La³⁺. We found that typical aging phenomena only existed in acceptor-dominant BaTiO₃. The results are explained by the Fe/La ratio dependence of oxygen vacancy concentration and a symmetry conforming short range ordering of the mobile oxygen vacancies. Furthermore, our results are compared with a recent study on Mn ³⁺-Nb⁵⁺ co-doped BaTiO₃, and the difference is briefly discussed.