Two new high-temperature molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),ReO_(4)^(-))  

作　　者：Keke Han Wenjun Rao Xiuli You Haina Zhang Xing Ye Zhenhong Wei Hu Cai 

机构地区：[1]School of Chemistry and Chemical Engineering,Nanchang University,Nanchang 330031,China [2]Jiangxi Key laboratory of Organic Chemistry,Jiangxi Science and Technology Normal University,Nanchang 330013,China

出　　处：《Chinese Chemical Letters》2024年第6期234-238,共5页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.21865015,22071094 and 22075123);the Department of Science and Technology in Jiangxi Province(No.20213BCJ22055)。

摘　　要：Molecular ferroelectrics have attracted much attention because of their excellent piezoelectricity,mechanical workability,and second harmonic effect.Here,we successfully prepared two molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),1;ReO_(4)^(-),2)by reactions of a quasi-spherical amine 1,5-diazabicycle[3.2.2]nonane(1.5-3.2.2-dabcn)with HX aqueous solution.Compounds 1 and 2 undergo hightemperature phase transitions at 381 K(1)and 396 K(2).Before and after the phase transition,they crystallize in the polar point group mm2,and the centrosymmetric point groups mmm and 4/mmm,respectively.According to Aizu rules,these two compounds experience mmm Fmm2 and 4/mmm Fmm2 type ferroelectric phase transitions,respectively.The ferroelectricity of both compounds is well expressed in their polycrystalline film at room temperature with low coercive voltages of 13 V for 1 and 25 V for 2.Using piezoelectric force microscopy(PFM),the 180°anti-parallel ferroelectric domains and the reversible polarization switching can be clearly observed in 1 and 2.This high-temperature molecular ferroelectric material has great application potential in flexible materials,biomechanics,intelligent wearables and other fields.

关 键 词：Ferroelectric domains Quasi-spherical amine Phase transition Polarization 

分 类 号：TM221[一般工业技术—材料科学与工程]