Energy-storage performance of NaNbO3-based ceramic capacitor derived from a high DOP glass network structure

0.75(0.4Na(2)O-0.1K(2)O-0.5Nb(2)O(5))-0.25(0.87SiO(2)-0.13BaO) glass-ceramics were prepared by a traditional melting method to optimize the crystallization kinetics. We obtained a glass network with high degree of polymerization (DOP) by crystallization at different temperatures and achieved a high energy storage density. The increase of crystallization temperature has promoted the precipitation of ferroelectric phases Na0.9K0.1NbO3 and NaNbO3 with high dielectric constant (1200-2000), promoted the increases of grain size from 0.76 mu m to 1.33 mu m, and reduced the gap width from 3.71eV to 3.22eV. When the crystallization temperature increased to 1000 degrees C-1100 degrees C, Ba2NaNb5O15 with low dielectric constant (similar to 460) increases, grain boundaries appear, and dielectric constant and BDS decrease. Among all the samples, the sample crystallized at 900 degrees C showed homogeneous and dense microstructure (grain size similar to 0.91 mu m). The experimental data confirmed that the glass sample crystallized at 900 degrees C achieves low dielectric loss (<0.005) and high dielectric constant (similar to 122). The glass sample crystallized at 900 degrees C sample had a maximum energy storage density of 3.65 J/cm(3), a power density of about 54 MW/cm(3) and a super-fast discharge speed of 38 ns at 660 kV/cm.