{"title":"Ferroelectricity and piezoelectricity in elemental α-X6 structure","authors":"Xuanlin Zhang, Luqi Dong, Yunhao Lu","doi":"10.1103/physrevmaterials.8.084401","DOIUrl":null,"url":null,"abstract":"Two-dimensional (2D) elemental ferroelectricity has recently been confirmed and arouses great interest in exploring new elemental asymmetric structures and their symmetry-breaking related properties. In this study, our density functional theory (DFT) calculations reveal the existence of coupled in-plane and out-of-plane electric polarizations in the group <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi mathvariant=\"normal\">V</mi></math> elements <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>α</mi><mtext>−</mtext><mrow><mi>X</mi></mrow><mn>6</mn></math> (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi mathvariant=\"italic\">X</mi><mo>=</mo><mi mathvariant=\"normal\">P</mi></mrow></math>, As). These ferroelectric phases are stabilized through charge transfer between <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>p</mi><mi mathvariant=\"normal\">x</mi></msub></math> orbitals. The introduction of compressive strain facilitates the transformation from blue phosphorene into <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>α</mi></math>-P6 phase with low reaction energy owing to their structural similarity. In addition, strain engineering or atom substitution can effectively reduce the polarization switching barrier. Furthermore, <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>α</mi><mtext>−</mtext><mrow><mi>X</mi></mrow><mn>6</mn></math> structure exhibits large longitudinal piezoelectric strain coefficients <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>d</mi><mn>11</mn></msub></math>, benefiting from their moderate <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>e</mi><mn>11</mn></msub></math> and flexible character. This discovery not only enriches the family of elemental ferroelectrics but also deepens the understanding of the origin of elemental polarization, offering potential candidates for ferroelectric and piezoelectric applications.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"15 1","pages":""},"PeriodicalIF":3.1000,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical Review Materials","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1103/physrevmaterials.8.084401","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Two-dimensional (2D) elemental ferroelectricity has recently been confirmed and arouses great interest in exploring new elemental asymmetric structures and their symmetry-breaking related properties. In this study, our density functional theory (DFT) calculations reveal the existence of coupled in-plane and out-of-plane electric polarizations in the group elements (, As). These ferroelectric phases are stabilized through charge transfer between orbitals. The introduction of compressive strain facilitates the transformation from blue phosphorene into -P6 phase with low reaction energy owing to their structural similarity. In addition, strain engineering or atom substitution can effectively reduce the polarization switching barrier. Furthermore, structure exhibits large longitudinal piezoelectric strain coefficients , benefiting from their moderate and flexible character. This discovery not only enriches the family of elemental ferroelectrics but also deepens the understanding of the origin of elemental polarization, offering potential candidates for ferroelectric and piezoelectric applications.
期刊介绍:
Physical Review Materials is a new broad-scope international journal for the multidisciplinary community engaged in research on materials. It is intended to fill a gap in the family of existing Physical Review journals that publish materials research. This field has grown rapidly in recent years and is increasingly being carried out in a way that transcends conventional subject boundaries. The journal was created to provide a common publication and reference source to the expanding community of physicists, materials scientists, chemists, engineers, and researchers in related disciplines that carry out high-quality original research in materials. It will share the same commitment to the high quality expected of all APS publications.