Dielectric Properties of Ca Doping α-BZN Ceramics

Bi1.5-CaZnNb1.5O6O (00.3) ceramics samples were prepared by conventional solid-state reaction methods. The effect of Ca2+ doping on dielectric properties, crystal chemistry characteristics and relaxor behavior of -BZN pyrochlore were investigated. The dielectric constant decreases with increasing Ca content. The bond valance calculations revealed the dielectric constant was proportional to bond valance sum of O anions. When = 0, the dielectric relaxation is attributed to hopping of A-site cations, however, when > 0, the declining relaxor behavior is closely related to the increasing A-O bond valance, the change from perfect octahedral to regular cube.