Design and optical properties of a new binary Bi1/2Na1/2TiO3-Eu1/2Na1/2TiO3 solid solution system

A new binary (1-x)Bi1/2Na1/2TiO3+xEu1/2Na1/2TiO3 system was synthesized by a simple chemical method. X-ray diffraction and Raman scattering studies on the crystal structure of Eu1/2Na1/2TiO3-modified Bi1/2Na1/2TiO3 materials proved that Eu1/2Na1/2TiO3 was well dissolved into the host Bi1/2Na1/2TiO3 materials. The random incorporation of impurity cations of Eu1/2Na1/2TiO3 materials during solute into host Bi1/2Na1/2TiO3 crystal resulted in compressing the rhombohedral structure of the host material. The random distribution of impurity cations of Eu1/2Na1/2TiO3 into the host Bi1/2Na1/2TiO3 lattices exhibited a complex change in the optical bandgap of pure Bi1/2Na1/2TiO3 materials with the value ranging from 3.04 eV to 2.89 eV. Strong photoemission of Eu1/2Na1/2TiO3-modified Bi1/2Na1/2TiO3 materials obtained at room temperature was related to electron transition from 4f-4f levels of Eu3+ cations incorporated with the host lattice. We expected our work to provide a simple method to integrate the photoluminescence properties in lead-free ferroelectric materials for innovative electronic applications.