Structural, optical, and magnetic properties of a new complex (1−x)Bi1/2Na1/2TiO3 + xMgNiO3−δ solid solution system

In this work, new complex binary solid solution (1−x)Bi1/2Na1/2TiO3 + xMgNiO3−δ materials had been synthesized by sol–gel method. Random incorporation of Mg and Ni cations into the host Bi1/2Na1/2TiO3 lattices resulted in a distortion of lattice parameters and reduced the optical bandgap. The optical bandgap was estimated at approximately 3.06 eV for the pure Bi1/2Na1/2TiO3 material and decreased to 2.82 eV for the 9 mol.%-MgNiO3−δ solid solution. The complex magnetic behaviors of the (1−x)Bi1/2Na1/2TiO3 + xMgNiO3−δ systems were achieved as a function of MgNiO3−δ amounts. The tunable magnetic properties of Bi1/2Na1/2TiO3 through MgNiO3−δ concentration control were important for integrating ferromagnetism into the lead-free ferroelectric Bi1/2Na1/2TiO3 materials. We expected our method to provide an important technique to tailor magnetic properties in lead-free ferroelectric materials for smart electronic applications.