Temperature Dependent Dielectric Behavior of Neodymium Substituted Barium Titanate Ceramic Compounds

In the present paper, we report the investigations on the temperature dependent dielectric properties of Nd substituted Barium titanate compounds with compositional formula of Ba_6-3xNd_8+2xTi₁₈O₅₄ with x = 0.0, 0.3 and 0.6 in a wide temperature range of −160°C to +160°C, at selected frequencies (10KHz, 50KHz, 100KHz, 500KHz, 1MHz). High temperature solid-state reaction technique was used for the synthesis. Variation of dielectric parameters (i.e. dielectric constant and loss tangent) with respect to temperature showed an anomaly that occurred at low temperatures for the three compositions that were synthesized. The temperature range in which the anomalies were observed was found to be −70°C to −90°C. Also, the temperature of the anomaly shifted to lower temperature with an increase in composition. Temperature coefficient of resonant frequency was estimated to be +92.2878 ppm/°C and was observed to be decreased with an increase in composition x.