CAJ | 학술논문

由于铅元素有毒，研究人员正努力寻找高性能无铅压电材料以便取代含铅压电材料，因此如何开发高性能压电材料的机制就变得极为重要。此文利用6阶朗道-德文希尔模型计算了不同相共存态的自由能表达（包括单相，两相，三相以及四相共存）。通过计算结果发现，不同的相共存态对应不同的自发极化伸缩或者偏转的能垒：铁电相共存越多，则极化偏转能垒越低，而与顺电相共存，则可以极大地降低极化伸缩能垒，不同的能垒也导致了对材料压电介电性能不同的增强能力。同时，不同相共存点的实验结果也证明了这一发现。研究澄清了相共存态与其对性能增强能力的关系，而且重新将极化伸缩和偏转机制（自由能观点）转变成了更简单的相共存态机理（材料结构观点），从而为寻找和制备高性能压电材料提供了一种更快捷的方式。
유우연원소유독，연구인원정노력심조고성능무연압전재료이편취대함연압전재료，인차여하개발고성능압전재료적궤제취변득겁위중요。차문이용6계랑도-덕문희이모형계산료불동상공존태적자유능표체（포괄단상，량상，삼상이급사상공존）。통과계산결과발현，불동적상공존태대응불동적자발겁화신축혹자편전적능루：철전상공존월다，칙겁화편전능루월저，이여순전상공존，칙가이겁대지강저겁화신축능루，불동적능루야도치료대재료압전개전성능불동적증강능력。동시，불동상공존점적실험결과야증명료저일발현。연구징청료상공존태여기대성능증강능력적관계，이차중신장겁화신축화편전궤제（자유능관점）전변성료경간단적상공존태궤리（재료결구관점），종이위심조화제비고성능압전재료제공료일충경쾌첩적방식。
Due to the toxicity of Pb, researchers are searching for high performance Pb free pi-ezoelectrics to substitute for the Pb based ones, and the mechanism for developing high perform-ance piezoelectrics are essentially needed.In this paper, we used a 6th order Landau-Devon-shire model to calculate the free energy for different phase coexistence situations ( single phase, two phases, three phases and four phases) .Results showed that different phase coexistence sta-tuses corresponded to different energy barriers for polarization rotation and extension: coexisted with more ferroelectric phases, the polarization rotation barrier will be lower, and coexisted with paraelectric phases, the polarization extension barrier will be extremely reduced, and different energy barriers result in different enhancement abilities for materials′piezoelectricity and permit-tivity.Experimental proofs were also provided to verify this finding .Our study clarifies the rela-tionship between phase coexistence states with its properties performance , and re-interprets po-larization rotation and extension mechanism ( a free energy view) into a simple phase coexistence scenario ( a material structure view) , which may offer a fast way to find and engineer high performance piezoelectrics .