摘要
采用传统固相反应法制备了K_(0.5)Na_(0.5)NbO_(3)(KNN)掺杂的无铅介电储能陶瓷BNT-BT-KNN,其组分配比为0.94Bi_(0.5)Na_(0.5)TiO_(3)-(0.06-x)BaTiO_(3)-xK_(0.5)Na_(0.5)NbO_(3)(BNT-BT+xKNN,x=0.00~0.04),并研究了KNN掺杂对BNT-BT基陶瓷材料晶相、微观结构、介电、铁电性能及储能的影响。结果表明:在1150℃温度下烧成后的陶瓷样品具有纯的钙钛矿结构,且样品的晶粒均匀致密;介电温谱显示,添加KNN后的BNT-BT铁电陶瓷在T_(m)处的介电峰进一步宽化,表现出更好的温度稳定性和弛豫性;同时随着KNN掺杂量的增加,样品的电滞曲线(P-E曲线)逐渐由“宽胖型”向“细长型”转变,样品的剩余极化强度(P_(r))逐渐降低,从而进一步提高了BNT-BT陶瓷的储能性能。在2 kV/mm的场强下,x=0.03时测得样品的储能密度最佳W_(rec)=0.048 J/cm^(3),对应的储能效率η=43%,显示该材料在储能电容器上具有良好的应用潜力。
A series of lead-free dielectric energy storage ceramics BNT-BT-KNN with a composition ratio of 0.94Bi_(0.5)Na_(0.5)TiO_(3)-(0.06-x)BaTiO_(3)-xK_(0.5)Na_(0.5)NbO_(3)(BNT-BT+xKNN,x=0.00~0.04)were prepared by solid state reaction method.The effect of KNN doping on the crystal structure,micro-structure,dielectric,ferroelectric properties and energy storage efficiency of BNT-BT-based ceramic was investigated.The results show that all the samples exhibit the pure perovskite structure with uniform and dense grains in the medium after sintering at 1150℃.The addition of KNN further broadens the dielectric peak at T_(m) which resulted in better temperature stability and relaxation.With the increase of KNN dopant,the hysteresis curves(P-E curves)of the samples gradually change from“broad and fat”to“slender”and the residual polarization(P r)of the ceramic samples decrease,thus the energy storage performance of BNT-BT ceramics are further improved.The optimal energy storage density of W_(rec)=0.048 J/cm^(3)was achieved at x=0.03 under a field strength of 2 kV/mm,which corresponds to an energy storage efficiency ofη=43%,which proves that this material has a promising potential for application in energy storage capacitors.
作者
苗健
邵辉
曹瑞龙
MIAO Jian;SHAO Hui;CAO Ruilong(School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)
出处
《人工晶体学报》
CAS
北大核心
2024年第5期882-888,共7页
Journal of Synthetic Crystals
基金
中国科学院无机功能材料与器件重点实验室开放课题(KLIFMD202301)。
关键词
BNT-BT陶瓷
KNN掺杂
固相反应法
弛豫
铁电性能
介电性能
储能
BNT-BT
KNN doping
solid state reaction method
relaxor
ferroelectric property
dielectric property
energy storage
