ABSTRACT Well-sintered (Na0.5K0.5)NbO3-x mol% V2O5 ceramics (abbreviated as NKN-V) with fine electrical properties were successfully prepared by conventional solid-state reaction through the careful control of processing conditions. The sintering behavior, phase structure, and electrical properties of the V2O5-doped NKN ceramics were investigated. Results show that when the V2O5 content is 0.6 mol%, the NKN ceramics attained the maximum density of 4.46 g/cm3 (about 98.9% of the theoretical density) at 1060°C, and therefore possessed enhanced electrical properties. But when the V2O5 content continued increasing, the density decreased. The secondary phase (Na2V6O16) could be detected by XRD analysis in all samples except x = 0 mol%. The Curie temperature of the NKN-based materials was found to decrease with the increase of V2O5. The dielectric properties of NKN ceramics doped with 0.6 and 0.9 mol% V2O5 were better than that of pure NKN ceramics. In addition, annealing treatment was proved to be an effective technique for improving dielectric properties and reducing the leakage current density.
Digital Object Identifier 10.1109/TUFFC.2008.745
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