0.94(Bi_(0.5)Na_(0.5)TiO_(3))-0.06BaTiO_(3)掺杂铌酸钠基反铁电陶瓷的储能特性研究

Energy storage properties of sodium niobate based antiferroelectric ceramics doped with 0.94(Bi_(0.5)Na_(0.5)TiO_(3))-0.06BaTiO_(3)

利用Bi^(3+)、Ba^(2+)取代A位Na^(+),利用Ti^(4+)取代B位Nb^(5+),以增强NaNbO_(3)基陶瓷的弛豫特性,获得较低的剩余极化强度。同时,Bi^(3+)6s和O^(2-)2p之间的轨道杂化及高极化率的Ba^(2+)的引入有利于陶瓷获得高极化强度,提高其储能特性。在此基础上,设计了(1-x)NaNbO_(3)-x[0.94(Bi_(0.5)Na_(0.5)TiO_(3))-0.06BaTiO_(3)](NN-x(BNT-BT),x=0.20,0.25,0.30,0.35)陶瓷体系,结合轧膜成型工艺,在1140~1160℃保温2 h制备出致密性良好的厚膜陶瓷样品。结果表明,随着BNT-BT掺杂量的增加,陶瓷的击穿强度明显提高。在外加电场为550 kV·cm^(-1)时,NN-0.35(BNT-BT)陶瓷的储能性能达到最优,储能密度和效率分别为6.7 J·cm^(-3)和79.67%。在外加电场为300 kV·cm^(-1)下,25~120℃温度范围内,NN-0.35(BNT-BT)陶瓷的储能密度和效率变化率分别为9%和7%;在10~500 Hz频率范围内,储能密度和效率变化率分别为3%和5%,表现出优异的温度和频率稳定性。此外,NN-0.35(BNT-BT)陶瓷兼具较高的功率密度(261.014 MW·cm^(-3))和较快的放电时间(19 ns),在脉冲电容器领域存在巨大的应用前景。

Bi^(3+)and Ba^(2+)was used to replace Na^(+)at the A-site,and Ti^(4+)was used to replace Nb^(5+)at the B-site to enhance the relaxor properties of NaNbO_(3)-based ceramics,resulting in lower remnant polarization and improved energy storage characteristics.Additionally,the orbital hybridization between Bi^(3+)6s and O^(2-)2p,as well as the introduction of highly polarizable Ba^(2+),contributes to achieving higher maximum polarization.Based on this,combined with viscous polymer rolling process(VPRP),the composition of(1-x)NaNbO_(3)-x[0.94(Bi_(0.5)Na_(0.5)TiO_(3))-0.06BaTiO_(3)](NN-x(BNT-BT),x=0.20,0.25,0.30 and 0.35)was designed and dense thick film ceramics were prepared at 1140℃to 1160℃for 2 h.The results show that with an increase in BNT-BT doping content,the breakdown strength of NN-x(BNT-BT)ceramics can be significantly improved.Under an applied electric field of 550 kV·cm^(-1),the NN-0.35(BNT-BT)ceramic exhibits optimal energy storage performance with energy density of 6.7 J·cm^(-3)and energy efficiency of 79.67%.Under an electric field of 300 kV·cm^(-1)and temperature range of 25-120℃,the NN-0.35(BNT-BT)ceramic shows good temperature stability,with variations in energy density and efficiency of 9%and 7%,respectively.Meanwhile,within a frequency range of 10-500 Hz,the variations in energy density and efficiency are 3%and 5%,respectively,demonstrating excellent frequency stability.Furthermore,the NN-0.35(BNT-BT)ceramic possesses high power density(261.014 MW·cm^(-3))and fast discharge time(19 ns),indicating great potential for application in the pulse capacitors field.