Synthesis and characterizations of NaNbO3 modified 0.92BaTiO3-0.08K0.5Bi0.5TiO3 ceramics for energy storage applications

In this work, (1 - x)(0.92BaTiO(3)-0.08K(0.5)Bi(0.5)TiO(3))-xNaNbO(3) (0 <= x <= 0.08) [(1 - x)BTKBT-xNN] ceramics were prepared by using conventional solid state reaction method. Phase composition, microstructures, and energy storage properties were investigated. X-ray diffraction analysis for all samples showed that the tetragonal symmetry structure of the (1 - x)BTKBT-xNN ceramics. It was found that the tetragonal phase content decreases with increasing NN content. Variation of defect dipole concentration leads to the average grain size of the (1 - x)BTKBT-xNN ceramics reduces from 1.49 to 0.90 mu m during sintering process. The 0.92BTKBT-0.08NN ceramic sample exhibits to processes the largest energy storage density of 1.96 J/cm(3) with energy storage efficiency about 67.4% at breakdown strength 22 kV/mm.