BaTiO₃-based ceramics with various grain sizes (136–529 nm) are prepared through a chemical coating method followed by sintering in a reducing atmosphere. Effects of grain size and temperature on electric properties, energy-storage properties, and dielectric tunability are studied via Current-Field (J-E) curves, ferroelectric hysteresis loops, Capacitance-Voltage (C–V) curves and Thermally stimulated depolarization currents (TSDC). At all temperatures, fine-grain ceramics yield a lower energy density but a higher energy efficiency under the same electric field, owing to a lower ferroelectric contribution. Meanwhile, fine-grain ceramics exhibit a higher maximum energy density due to their higher breakdown strength. Fine-grain ceramics with the grain size of 136 nm have the maximum energy density of 0.41 J/cm³ under the breakdown strength of 75 kV/cm, the corresponding efficiency is 81%. C–V curves show that fine-grain ceramics have better bias-field stability. According to TSDC results, fine-grain ceramics exhibit fewer oxygen vacancies and a higher relaxation activation energy.

通过化学涂覆方法，然后在还原性气氛中进行烧结，可以制备出具有各种晶粒尺寸（136–529 nm）的BaTiO ₃基陶瓷。通过电流场（JE）曲线，铁电磁滞回线，电容-电压（C–V）曲线和热激发去极化电流（TSDC）研究了晶粒尺寸和温度对电性能，储能性能和介电可调性的影响。在所有温度下，由于铁电贡献较低，在相同电场下，细晶粒陶瓷的能量密度较低，但能量效率较高。同时，细粒陶瓷由于其较高的击穿强度而具有较高的最大能量密度。晶粒尺寸为136 nm的细晶粒陶瓷的最大能量密度为0.41 J / cm³在击穿强度为75 kV / cm时，相应的效率为81％。C–V曲线表明，细晶粒陶瓷具有更好的偏置场稳定性。根据TSDC结果，细晶粒陶瓷的氧空位较少，弛豫活化能较高。