A new microwave dielectric material ZnZr0.8Sn0.2Nb2O8

Abstract

A novel low-loss microwave dielectric material ZnZr0.8Sn0.2Nb2O8 was reported for the first time. The samples were prepared by the conventional solid-state reaction route and sintered in the temperature range of 1225–1325 °C for 6 h. Single phase ZnZr0.8Sn0.2Nb2O8 was obtained and it showed monoclinic structure. The microstructure and microwave dielectric properties were investigated systematically. The variation trend of dielectric constant (e r ) was in accordance with variation trend of relative density. The Qf value mainly depended on the crystal structure and it increased with the increasing packing fraction. The temperature coefficient of resonant frequency (τ f ) correlated with the variation of bond valence of B-site. The excellent microwave dielectric properties of e r = 27.37, Q × f = 76,814 GHz (where f = 7 GHz), and τ f = −55.09 × 10−6/ °C were obtained for ZnZr0.8Sn0.2Nb2O8 ceramics sintered at 1275 °C for 6 h.