Effect of Nanometer Niobium Oxide Additions on Electrical Properties of Barium Titanate Prepared by Spark Plasma Sintering (SPS) Method

In this research, the effect of nanometer niobium oxide additions on electrical properties of barium titanate was investigated. 0.1, 0.2, 0.3 and 0.6 wt.% niobium oxide was added to barium titanate using planetary mill and ethanol media. The dried powder mixtures were spark plasma sintered at 1100, 1200 and 1300 °C and the characteristics of sintered samples were evaluated by XRD, SEM and LCR meter. XRD results showed no decomposition of initial phases and formation of new phase by adding niobium oxide while the microscopic investigation revealed the particle size reduction of barium titanate by increasing niobium oxide. Sample containing 0.3 %wt. niobium oxide sintered at 1300 °C had the maximum density of 99.5 and dielectric constant of 6300. On the other hand, sample containing 0.1 %wt. niobium oxide sintered at 1100 °C obtained the lowest density of 95.5 which showed optimal PTCR properties rather than other samples because of the sharp change in slope of the resistivity at Curie temperature.