Effects of silver and palladium doping on the dielectric properties of 0.9Pb(Mg1/3Nb2/3)O-3-0.1PbTiO(3) ceramic

The doping of silver and palladium into a 0.9Pb(Mg1/3Nb2/3)O-3-0.1PbTiO(3) (PMN-PT) ceramic has been investigated. It was found that Ag could be incorporated into the PMN-PT lattice, though this was almost impossible with Pd, Doping at up to 0.2 mol% of Ag and Pd reduced the maximum dielectric constant (K-max) from 21000 to 14000 without any conspicuous change in physical properties. Order-disorder transitions in the perovskite structure contributed to the decrease in K-max, since the diffuseness parameter, delta, which represents the degree of the order-disorder relationship, increased with Ag doping, However, addition of more than 0.2 mol% increased K-max. Increases in grain size and in the perovskite ratio contributed to this increase, The dielectric properties of Ag/Pd-doped samples were intermediate between the Ag- and Pd-doped samples.