Van der Waals force-induced intralayer ferroelectric-to-antiferroelectric transition via interlayer sliding in bilayer group-Ⅳmonochalcogenides

作     者：Bo Xu Junkai Deng Xiangdong Ding Jun Sun Jefferson Zhe Liu 

作者机构：State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong University710049Xi’anChina Department of Mechanical EngineeringThe University of MelbourneParkvilleVIC3010Australia 

出 版 物：《npj Computational Materials》 (计算材料学（英文）)

年 卷 期：2022年第8卷第1期

页      面：446-454页

核心收录：

学科分类：0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 070205[理学-凝聚态物理] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0702[理学-物理学] 

基　　金：The authors gratefully acknowledge the support of NSFC(Grant Nos.11974269,51728203) the support by 111 project 2.0(Grant No.BP0618008) J.D.also thanks the support of the National Key R&D Program of China(Grant No.2018YFB1900104) J.Z.L.acknowledges the support from ARC discovery projects(DP180101744)and HPC from National Computational Infrastructure from Australia This work is also supported by State Key Laboratory for Mechanical Behavior of Materials 

主　　题：ferroelectric interlayer layer 

摘      要：Two-dimensional materials with ferroelectric properties break the size effect of conventional ferroelectric materials and unlock unprecedented potentials of ferroelectric-related application at small length *** first-principles calculations,a sliding-induced ferroelectric-to-antiferroelectric behavior in bilayer group-IV monochalcogenides(MX,with M=Ge,Sn and X=S,Se)is *** this mechanism,the top layer exhibits a reversible intralayer ferroelectric switching,leading to a reversible transition between the ferroelectric and antiferroelectric states in the bilayer *** results show that the interlayer van der Waals interaction,which is usually considered to be weak,can actually generate an in-plane lattice distortion and thus cause the breaking/forming of intralayer covalent bonds in the top layer,leading to the observed anomalous *** unique property has advantages for energy harvesting over existing piezoelectric and triboelectric *** interlayer sliding-induced big polarization change(40μC cm^(−2))and ultrahigh polarization changing rate generate an open-circuit voltage two orders of magnitude higher than that of MoS_(2)-based *** theoretical prediction of power output for this bilayer MXs at a moderate sliding speed 1 m s^(−1)is four orders of magnitude higher than the MoS_(2)nanogenerator,indicating great potentials in energy harvesting applications.