Phase Transition Characteristics in A-Site La3+ Modified Bi-Layered Aurivillius-Type Structure SrBi2Nb2O9 Ferroelectric Ceramics

The phase transition characteristics have been investigated in lanthanum modified bismuth layer structured SrBi2Nb2O9 (SBN) ferroelectric ceramics, obtained from the conventional sintering method. In particular, structural, ferroelectric and dielectric properties have been analyzed taking into account the influence of the lanthanum content. Results of Raman spectroscopy as well as dielectric response suggested an evolution from normal ferroelectric-paraelectric phase transition to a relaxor-like behavior of the SLBN system, with the increase of the lanthanum concentration. The compositional cationic disorder has been considered as the main cause for the observed behavior, affecting the evolution of the long-rage polar ordering in the studied system.