Dielectric Properties of Undoped and Li-doped Pb(Fe1/2Nb1/2)O3 Ceramics Sintered from Mechanochemically Synthesized Powders

Optimal sintering temperature of PbFe1/2Nb1/2O3 (PFN) ceramics is 1120-1150 degrees C, but ceramics sintered in this temperature range have low resistivity and high losses. Mechanochemical synthesis allows one to lower the optimal sintering temperature of PFN ceramics down to 1000 degrees C, however dielectric losses remain high and the permittivity exhibits large frequency dispersion. In the present work it has been found that similar to the case of the routine solid state synthesis, Li doping enables one to reduce dramatically the losses of the PFN ceramics obtained by sintering the mechanochemically synthesized powders.