Effect of Ag on the sintering and dielectric properties behavior of Bi1.5ZnNb1.5O7 ceramics

Bi1.5ZnNb1.5O7-Ag composites were prepared by solid state method. The sintering temperature was lowered to 900 degrees C for the Bi1.5ZnNb1.5O7 ceramics with 3 wt% silver doping. The microstructures, surface morphologies, and dielectric properties of the composites were investigated. A small amount of silver doping is shown to promote grain growth. The grain size of the composites sintered at 950 degrees C increased from 2 to 6 mu m with the silver content increasing from 1 to 4 wt%. The composites with 4 wt% silver sintered at 950 degrees C had the relative permittivity of 215, and dielectric loss of 10(-4) ranging from 100 Hz to 1 MHz. The silver doping in composites also improves the electrical resistivity of Bi1.5ZnNb1.5O7-Ag composites, and increases the electrical resistivity value from 10(13) to 10(15) Omega cm for the samples sintered at 900 or 950 degrees C by increasing the silver content from 1 to 4wt%. The Bi1.5ZnNb1.5O7-Ag composites with lower loss and larger electrical resistivity would be useful for electronic devices in RF application. (c) 2009 Elsevier B.V. All rights reserved.