Stabilized antiferroelectricity in xBiScO₃-(1-x)NaNbO₃ lead-free ceramics with established double hysteresis loops

We previously reported various solid solution systems that demonstrated the stabilized antiferroelectric (P) phases in NaNbO₃ through lowering the tolerance factor. However, all those reported modifications were achieved by adding A²⁺B⁴⁺O₃ type solid solutions. A lead-free antiferroelectric (AFE) solid solution xBiScO₃-(1-x)NaNbO₃ was rationalized by adopting the tolerance factor design rule. Specifically, adding BiScO₃ was found to effectively stabilize the AFE phase without changing the crystal symmetry of NaNbO₃. Microstructure and electron zone axis diffraction patterns from transmission electron microscopy revealed the stabilized AFE (P) phase in this solid solution. Besides, the electric-field-induced polarization with a double-hysteresis loop was observed. The present results pointed out that the strategy could also be applied while adding A³⁺B³⁺O₃ type solid solutions. In addition, it expanded the compositional design that can be applied to antiferroelectric materials.