ZnNb_(2)O_(6)掺杂BNT基无铅弛豫铁电体陶瓷的性能研究  

Properties of ZnNb_(2)O_(6)Doped BNT-Based Lead-Free Relaxor Ferroelectric Ceramics

作　　者：肖齐龙 王世宇 蒋芮 梅雄峰 吴昊[1] 石亚军 孙帅 吴文娟 XIAO Qilong;WANG Shiyu;JIANG Rui;MEI Xiongfeng;WU Hao;SHI Yajuan;SUN Shuai;WU Wenjuan(College of Optoelectronic Engineering,Chengdu University of Information Technology,Chengdu 610025,China)

机构地区：[1]成都信息工程大学光电工程学院,成都610025

出　　处：《人工晶体学报》2024年第1期154-162,共9页Journal of Synthetic Crystals

基　　金：四川省科技计划(2022YFG0099);四川省大学生创新创业训练计划(S202210621078)。

摘　　要：利用传统固相法制备了0.7(Na_(0.5)Bi_(0.5))TiO_(3)-0.3(Sr_(0.7)Bi_(0.2))TiO_(3)-xZnNb_(2)O_(6)(缩写为BNT-SBT-xZN,其中x=0.5%、1.0%、1.5%和2.0%(摩尔分数))陶瓷,并研究了引入ZnNb2O6对BNT基陶瓷材料的结构和性能的影响规律。结果表明:少量ZnNb_(2)O_(6)掺杂(x=0.5%时)的BNT-SBT-xZN陶瓷具有纯的钙钛矿结构,且微观结构致密,无第二相,在室温时为典型的弛豫铁电体(弥散指数γ>1.7),极化前后样品的铁电-弛豫转变温度(TR-E)均低于室温,而与三方相R3c和四方相P4bm的纳米极性微区(PNRs)热弛豫有关的介电反常出现在TR-E<100℃;当ZnNb_(2)O_(6)含量增多时,遍历弛豫态逐渐起主导作用,最大极化强度(Pmax)和剩余极化强度(Pr)均出现减小趋势。综合来看,x=0.5%的BNT-SBT-xZN陶瓷具有高的Pmax、低的Pr、大的ΔP,并具备良好的储能特性及频率和温度稳定性,在室温电场强度为110 kV/cm时,Pmax=44.7μC/cm^(2),Pr=12.4μC/cm^(2),ΔP=32.3μC/cm^(2),储能密度W1=1.066 J/cm^(3),储能效率η=48.68%。此外,x=0.5%的BNT-SBT-xZN陶瓷在100 kV/cm的电场强度下充放电性能良好,放电能量密度Wd=0.60 J/cm^(3),最大放电电流Imax=45.33 A,电流密度CD=1443 A/cm^(2),功率密度PD=72.2 MW/cm^(3)。In this paper,0.7(Na_(0.5)Bi_(0.5))TiO_(3)-0.3(Sr_(0.7)Bi_(0.2))TiO_(3)-x ZnNb_(2)O_(6)(abbreviated as BNT-SBT-x ZN,where x=0.5%,1.0%,1.5%and 2.0%,molar fraction)ceramics were prepared by the solid-state reaction method.The effect of ZnNb_(2)O_(6)doping on the structure and properties of BNT-based ceramic materials was studied.The results show that,BNT-SBT-x ZN ceramics doped with a small amount of ZnNb_(2)O_(6)(x=0.5%)have pure perovskite structure with compact microstructure and no second phase.At room temperature,they are typical relaxor ferroelectrics(dispersion indexγ>1.7).For all unpoled and poled BNT-SBT-x ZN ceramics of x=0.5%,the transition temperature of ferroelectric-relaxation(T R-E)is lower than room temperature,while T R-E is below 100℃,which denotes the dielectric anomalous associated with thermal relaxation of polar nano regions(PNRs)in rhombohedral(R3c)and tetragonal(P4bm)symmetrical structure.When the content of ZnNb_(2)O_(6)increases,the ergodic relaxor state gradually plays a dominant role,maximum polarization(P max)and remanent polarization(P r)both show a decreasing trend.BNT-SBT-x ZN ceramics with x=0.5%have high P max,low P r and largeΔP,resulting in excellent energy storage characteristics and frequency and temperature stability with P max of 44.7μC/cm^(2),P r of 12.4μC/cm^(2),ΔP of 32.3μC/cm^(2),energy density(W 1)of 1.066 J/cm^(3),energy storage efficiency(η)of 48.68%under 110 kV/cm.Moreover,discharge energy density W d,maximum discharge current I max,current density C D and power density P D of 0.60 J/cm^(3),45.33 A,1443 A/cm^(2)and 72.2 MW/cm^(3)are obtained at room temperature and 100 kV/cm,respectively.

关 键 词：BNT基陶瓷 弛豫铁电体 ZnNb_(2)O_(6) 介电性能 铁电性能 储能特性 

分 类 号：TM282[一般工业技术—材料科学与工程] TQ174.1[电气工程—电工理论与新技术]