Optimized Energy Storage Performance in NaNbO3-based Ceramics Via Composition Modification and Micro-Structure Control

Lead-free ceramics with high effective energy density (W-rec), high energy storage efficiency (?), and excellent fatigue resistance are crucial for dielectric capacitors. NaNbO3-ceramics have attracted wide attention because of their excellent performance. Therefore, (1-x) [0.76NaNbO(3)-0.24(Bi0.5Na0.5) TiO3]-xSrTiO(3) (x = 0.01,0.02,0.03,0.04) ceramics with better W-rec and high ? were gained by a traditional solid-state sintering technology. High Eb of 270 kV/cm was obtained via regulating smaller grain size and better density, which is the micro-structure control. (Bi0.5Na0.5) TiO3 and SrTiO3 were incorporated into the NaNbO3 lattice to break the macroscopic ordered domain structure to form a construct polar nanoregions, which is the componentmodification control. Finally, an excellent hardness of 6.80 GPa, frequency(5Hz-80Hz), and temperature (25?-120 ?) stability was also achieved. A moderate W-rec of 2.64 J/cm(3), and high ? of 89.9% were gained in the 0.97[0.76NaNbO(3)-0.24(Bi0.5Na0.5) TiO3]-0.03SrTiO(3) ceramic. Overall, this work shows that the x = 0.03 ceramic system can be regarded as the most potential and viable energy storage material.