Relative stability of a ferroelectric state in (Na0.5Bi0.5)TiO3-based compounds under substitutions: Role of a tolerance factor in expansion of the temperature interval of stable ferroelectric state

TL;DR

This study investigates how B-site ion substitutions in (Na0.5Bi0.5)TiO3-based compounds affect the stability of ferroelectric and antiferroelectric phases, highlighting the role of the tolerance factor in expanding the stable ferroelectric temperature range.

Contribution

It demonstrates the influence of ion size and tolerance factor on phase stability, providing insights for increasing the ferroelectric transition temperature in these materials.

Findings

Increase in ion concentration alters lattice size linearly.

Tolerance factor correlates with transition temperature changes.

Ion size predominantly influences phase stability.

Abstract

The influence of the B-site ion substitutions in (1-x)(Bi1/2Na1/2)TiO3-xBaTiO3 system of solid solutions on the relative stability of the ferroelectric and antiferroelectric phases has been studied. The ions of zirconium, tin, along with (In0.5Nb0.5), (Fe0.5Nb0.5), (Al0.5V0.5) ion complexes have been used as substituting elements. An increase in the concentration of the substituting ion results in a near linear variation in the size of the crystal lattice cell. Along with the cell size variation a change in the relative stability of the ferroelectric and antiferroelectric phases takes place according to the changes of the tolerance factor of the solid solution. An increase in the tolerance factor leads to the increase in the temperature of the ferroelectric-antiferroelectric phase transition, and vice versa. All obtained results demonstrate the predominant influence of the ion size factor on the relative stability of the ferroelectric and antiferroelectric states in the (Na0.5Bi0.5)TiO3-based solid solutions and indicate the way for raising the temperature of the ferroelectric-antiferroelectric phase transition.