Improving high-field strain and temperature stability on KNN-based ceramics sintered in reducing atmosphere via defect engineering  

作　　者：Zhenyong Cen Meiyi Feng Fuzhi Cao Yuqi Jiang Ze Xu Changrong Zhou Ke Wang Nengneng Luo 

机构地区：[1]State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures,MOE Key Laboratory of New Proce sing Technology for Nonferrous Metals and Materials,School of Resources,Environment and Materials,Guangxi Univers ity,Nanning,530004,China [2]Guangexi Key Laboratory of Information Materials,Guilin University of Electronic Technology,Guilin,541004,China [3]State Key Laboratory of New Ceramics and Fine Processing,School of Materials Science and Engineering Tsinghua University,Beijing 100084,China

出　　处：《Journal of Materiomics》2024年第6期1165-1175,共11页无机材料学学报（英文）

基　　金：The work was supported by Guangxi Science,Technology Base and Talent Special Project(GUIKE AD23026063);Guangxi Natural Science Foundation Project(2022GXNSFBA035573);State Key Laboratory of New Ceramic and Fine Processing Tsinghua Univer-sity(KF202306).

摘　　要：High-field strain and its temperature stability of(1-x)K_(0.48)Na_(0.52)Nb_(0.96)Ta_(0.04)O_(3)-xBaZrO_(3)+8%MnO+3%ZrO_(2)(in mole,KNNT-xBZ+8Mn)ceramics sintered in reducing atmosphere are improved simultaneously via defect design in A and B site.There is a conducting type transition from n-type to p-type at x=0.07.The BaZrO_(3) dopant not only induces the increase of defects(Zr′_(Nb),Ba_(Na),Ba_(K))concentration,but also results in the increase of defect(Mn″_(Nb))concentration,because more Mn ions as+2 oxidation state in ceramics is triggered by BaZrO3 doping modifcation.Defect dipoles(Mn″_(Nb)-V_(o),Zr′_(Nb)-V_(o),Ba_(Na)-V′_(Na),Ba_(Na)-V′_(Na))in poled and aged ceramics enhance the reversibility of the non-180°domains switching,which increases the high-field strain of KNNT-xBZ+8Mn ceramics.The reversibility of non-180°domain switching can be preserved to high temperature due to stable defect dipoles(Ba_(Na)-V′_(Na),Ba_(K)-V′_(K))in A-site.The KNNT-xBZ+8Mn ceramics at x=0.07 show the largest high-field strain coefficient(543 pm/V@20 kV/cm)and the highest temperature stability(125℃).The KNNT-xBZ+8Mn ceramic is a lead-free material with great potential to be applied in the fabrication of multilayer ceramic actuators with Ni inner electrodes in the future.

关 键 词：Lead-free ceramics Piezoelectric materials Reducing atmosphere DEFECTS 

分 类 号：TQ174.1[化学工程—陶瓷工业]