Calcium Bismuth Titanate with High Curie Temperature (Tc) for High-Temperature Sensor Applications.

Bismuth layer-structured ferroelectric (BLSF) ceramics exhibit linearity in resistivity with respect to temperature changes, and therefore find application as high-temperature sensor materials. In this study, calcium bismuth titanate (CBT), a BLSF material, was synthesized by calcining combined oxide precursors at 850°C for 2 h, and its particle size distribution, phase analysis, grain size distribution and morphology were characterized. Circular discs were prepared by sintering in the temperature range of 1000 to 1200°C. The sintered discs were characterized for dielectric constant (K), P-E hysteresis loop and DC electrical resistivity (ρ) from 100 to 900°C. The highest density (> 95% Th.) was obtained for samples sintered at 1175°C. DC resistivity decreased linearly from 10¹⁴ to 10⁵ Ω cm with the rise in temperature from 100 to 900°C, therefore confirming CBT as a prospective high-temperature sensor material. [ABSTRACT FROM AUTHOR]