Ultra-Wide Temperature Stable Dielectrics Based on Bi0.5 Na0.5 TiO3 -NaNbO3 System

The microstructure, phase structure, ferroelectric, and dielectric properties of (1−x)Bi0.5Na0.5TiO3-xNaNbO3 [(1−x)BNT-xNN] ceramics conventionally sintered in the temperature range of 1080°C–1120°C were investigated as a candidate for capacitor dielectrics with wide temperature stability. Perovskite phase with no secondary impurity was observed by XRD measurement. With increasing NN content, (1−x)BNT-xNN was found to gradually transform from ferroelectric (x = 0–0.05) to relaxor (x = 0.10–0.20) and then to paraelectric state (x = 0.25–0.35) at room temperature, indicated by P–I–E loops analysis, associated with greatly enhanced dielectric temperature stability. For the samples with x = 0.25–0.35, the temperature coefficient of capacitance (TCC) was found