Crystal engineering regulation achieving inverse temperature symmetry breaking ferroelasticity in a cationic displacement type hybrid perovskite system  

作　　者：Na Wang Wang Luo Huaiyi Shen Huakai Li Zejiang Xu Zhiyuan Yue Chao Shi Hengyun Ye Leping Miao 

机构地区：[1]Chaotic Matter Science Research Center,Department of Materials,Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou 341000,China

出　　处：《Chinese Chemical Letters》2024年第5期477-481,共5页中国化学快报（英文版）

基　　金：support from the National Natural Science Foundation of China(No.22175079);support from the National Natural Science Foundation of China(No.22205087);the Open Project Program of Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry,Jiangxi University of Science and Technology(No.20212BCD42018);National Natural Science Foundation of China(No.22275075);Natural Science Foundation of Jiangxi Province(Nos.20204BCJ22015 and 20202ACBL203001).

摘　　要：Ferroelastic hybrid perovskite materials have been revealed the significance in the applications of switches,sensors,actuators,etc.However,it remains a challenge to design high-temperature ferroelastic to meet the requirements for the practical applications.Herein,we reported an one-dimensional organicinorganic hybrid perovskites(OIHP)(3-methylpyrazolium)CdCl_(3)(3-MBCC),which possesses a mmmF2/m ferroelastic phase transition at 263 K.Moreover,utilizing crystal engineering,we replace-CH_(3) with-NH_(2) and-H,which increases the intermolecular force between organic cations and inorganic frameworks.The phase transition temperature of(3-aminopyrazolium)CdCl_(3)(3-ABCC),and(pyrazolium)CdCl_(3)(BCC)increased by 73 K and 10 K,respectively.Particularly,BCC undergoes an unconventional inverse temperature symmetry breaking(ISTB)ferroelastic phase transition around 273 K.Differently,it transforms from a high symmetry low-temperature paraelastic phase(point group 2/m)to a low symmetry high-temperature ferroelastic phase(point group ī)originating from the rare mechanism of displacement of organic cations phase transition.It means that crystal BCC retains in ferroelastic phase above 273 K until melting point(446 K).Furthermore,characteristic ferroelastic domain patterns on crystal BCC are confirmed with polarized optical microscopy.Our study enriches the molecular mechanism of ferroelastics in the family of organic-inorganic hybrids and opens up a new avenue for exploring high-temperature ferroic materials.

关 键 词：Organic-inorganic hybrid perovskite Crystal engineering Inverse temperature symmetry breaking Displacement type phase transition FERROELASTICITY 

分 类 号：TB34[一般工业技术—材料科学与工程]