Modulation of phase boundary and domain structures to engineer strain properties in BNT-based ferroelectrics  

作　　者：Yule Yang Zhiyong Liu Pengrong Ren Yuqing Mao Haijun Sun Bingliang Liang Pu Mao Kun Guo Bing Xie Longlong Shu 

机构地区：[1]School of Materials Science and Engineering,Nanchang Hangkong University,Nanchang 330063,China [2]School of Materials Science and Engineering,Xi'an University of Technology,Xi’an 710048,China [3]School of Aircraft Engineering,Nanchang Hangkong University,Nanchang 330063,China [4]School of Physics and Materials Science,Nanchang University,Nanchang 330031,China

出　　处：《Journal of Advanced Ceramics》2024年第7期967-975,共9页先进陶瓷（英文）

基　　金：supported by the National Natural Science Foundation of China(No.52162019);the Natural Science Foundation of Jiangxi Province(No.20232BAB204016).

摘　　要：Bismuth sodium titanate(BNT)ceramics exhibit outstanding strain responses but are unfavorable for application in high-sensitivity displacement actuators due to the large negative strain resulting from irreversible changes in their phase transition and domain structure.Here,(1−x)Bi_(0.50)Na_(0.41)K_(0.09)TiO_(3)-xNaNbO_(3)(BNKT−xNN)solid solutions were prepared to improve the strain properties through the strategy of modulating the phase boundary and domain structures.The introduction of sodium niobate could effectively regulate the relative content of the tetragonal(P4bm)and rhombohedral(R3c)phases in the phase boundary region.The ferroelectric-to-relaxor phase transition(T_(F−R))was reduced,and the ergodic relaxor(ER)state was nurtured at room temperature.Excellent zero-negative strain properties of S=0.41%and d_(33)^(*)=742 pm/V were achieved from the reversible transition between the ER and ferroelectric states under an applied electric field(x=0.04).Additionally,understanding the domain states via piezoelectric force microscopy(PFM)and firstorder reversal curve(FORC)revealed that the superior strain responses originated from the reversible inter-transformation of substable macrodomains and polar nanoregions(PNRs)in the phase boundary.This study provides new insight into the interplay between the evolution of phase boundaries and domain structures and the strain properties of BNT-based ceramics.

关 键 词：bismuth sodium titanate(BNT) domain structure phase boundary strain response relaxor state 

分 类 号：TQ174.75[化学工程—陶瓷工业]