The structure and properties of Ag(Nb0.8Ta0.2)O3 ceramic doped with MnNb2O6

The influences of doping of MnNb₂O₆ on the structure and dielectric properties of Ag(Nb0.8Ta_0.2)O₃ were illustrated. Ag(Nb_0.8Ta_0.2)O₃ samples doped with different amount of preformed MnNb₂O₆ (1 mol%, 2 mol%, 3 mol%, 4 mol%, 6 mol%, 8 mol%) were prepared by traditional solid-state reaction method and characterized by XRD, SEM and EDS, and the dielectric properties of samples were compared. The experiment results indicated that when the doping amount of MnNb₂O₆ was greater than 3 mol%, second phase appeared because of the solid solution limit. The permittivity of the Ag(Nb_0.8Ta_0.2)O₃ samples doped with MnNb₂O₆ firstly increased and then decreased with the sintering temperature, while the dielectric loss decreased first, and then increased slightly. 1 100 °C seems to be the most proper sintering temperature for most of the samples. When the amount of MnNb₂O₆ is about 3 mol%, the samples have the best dielectric properties, larger permittivity and smaller dielectric loss.