Excellent stability and low dielectric loss of Ba(Fe sub(0.5)Nb sub(0.5))O sub(3) synthesized by a solution precipitation method

A solution precipitation method was applied to prepare Ba(Fe sub(0.5)Nb sub(0.5))O sub(3) powders. Nano-size BFN powders with uniform particles size ( similar to 40 nm) were synthesized by solution precipitation method, which is beneficial to calcine at low temperature (1223 K). The sintering sample with dense microstructure and uniform grain size (15 mu m) was obtained at 1673 K, which exhibits enhanced dielectric properties. The dielectric loss of BFN ceramic could be significantly reduced by solution precipitation method. The frequency and temperature stability of BFN ceramics could also be improved. The complex impedance spectroscopy analysis results suggested that the obtained Ba(Fe sub(0.5)Nb sub(0.5))O sub(3) ceramics, consisting of semiconducting grains and insulating grain boundaries, were electrically heterogeneous. The grain boundary effect was responsible for such a high value of dielectric constant.