{"title":"单轴拉伸下碘化铯锡包晶石的各向异性力学行为","authors":"Amith Adoor Cheenady, Krishna Rajan","doi":"10.1103/physrevmaterials.8.093607","DOIUrl":null,"url":null,"abstract":"Lead-based metal halide perovskites (MHPs) have wide-ranging applications as solar cells, field-effect transistors, diodes, and photodetectors. However, their poor stability and concerns about toxicity have enabled lead-free tin-based MHPs to emerge as a promising alternative. We utilize molecular dynamics (MD) simulations to investigate the anisotropic mechanical behavior of single-crystal cubic <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\"normal\">I</mi><mn>3</mn></msub></mrow></math>, a promising lead-free MHP, under uniaxial tension. Among the three investigated crystal orientations, [111] is found to be the strongest and to exhibit the highest ultimate strain while [100] is the weakest. While shear strain localization and amorphization precede fracture along [100], fracture directly follows strain localization along [110] and [111]. We also investigated the influence of a crystal defect, in the form of an embedded rectangular crack, on the anisotropic mechanical behavior of cubic <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\"normal\">I</mi><mn>3</mn></msub></mrow></math>. The presence of crystal defects is found to substantially reduce the anisotropy in mechanical properties, with very similar crack growth behavior and almost identical stress-strain response noted along starkly different crystal orientations of loading. Finally, the ultimate strengths and ultimate strains of cubic <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\"normal\">I</mi><mn>3</mn></msub></mrow></math> determined here are comparable to or higher than those of cubic <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>CsPb</mi><msub><mi mathvariant=\"normal\">I</mi><mn>3</mn></msub></mrow></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>MAPb</mi><msub><mi mathvariant=\"normal\">I</mi><mn>3</mn></msub></mrow></math> determined in prior MD-based investigations. Thus, our study supports the applicability of cubic <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\"normal\">I</mi><mn>3</mn></msub></mrow></math> as a lead-free alternative to commonly used cubic MHPs, while the sensitivity to crystal defects revealed here underlines the importance of defect control for obtaining robust devices with reliable properties.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"99 1","pages":""},"PeriodicalIF":3.1000,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Anisotropic mechanical behavior of cesium tin iodide perovskite subjected to uniaxial tension\",\"authors\":\"Amith Adoor Cheenady, Krishna Rajan\",\"doi\":\"10.1103/physrevmaterials.8.093607\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Lead-based metal halide perovskites (MHPs) have wide-ranging applications as solar cells, field-effect transistors, diodes, and photodetectors. However, their poor stability and concerns about toxicity have enabled lead-free tin-based MHPs to emerge as a promising alternative. We utilize molecular dynamics (MD) simulations to investigate the anisotropic mechanical behavior of single-crystal cubic <math xmlns=\\\"http://www.w3.org/1998/Math/MathML\\\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\\\"normal\\\">I</mi><mn>3</mn></msub></mrow></math>, a promising lead-free MHP, under uniaxial tension. Among the three investigated crystal orientations, [111] is found to be the strongest and to exhibit the highest ultimate strain while [100] is the weakest. While shear strain localization and amorphization precede fracture along [100], fracture directly follows strain localization along [110] and [111]. We also investigated the influence of a crystal defect, in the form of an embedded rectangular crack, on the anisotropic mechanical behavior of cubic <math xmlns=\\\"http://www.w3.org/1998/Math/MathML\\\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\\\"normal\\\">I</mi><mn>3</mn></msub></mrow></math>. The presence of crystal defects is found to substantially reduce the anisotropy in mechanical properties, with very similar crack growth behavior and almost identical stress-strain response noted along starkly different crystal orientations of loading. Finally, the ultimate strengths and ultimate strains of cubic <math xmlns=\\\"http://www.w3.org/1998/Math/MathML\\\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\\\"normal\\\">I</mi><mn>3</mn></msub></mrow></math> determined here are comparable to or higher than those of cubic <math xmlns=\\\"http://www.w3.org/1998/Math/MathML\\\"><mrow><mi>CsPb</mi><msub><mi mathvariant=\\\"normal\\\">I</mi><mn>3</mn></msub></mrow></math> and <math xmlns=\\\"http://www.w3.org/1998/Math/MathML\\\"><mrow><mi>MAPb</mi><msub><mi mathvariant=\\\"normal\\\">I</mi><mn>3</mn></msub></mrow></math> determined in prior MD-based investigations. Thus, our study supports the applicability of cubic <math xmlns=\\\"http://www.w3.org/1998/Math/MathML\\\"><mrow><mi>CsSn</mi><msub><mi mathvariant=\\\"normal\\\">I</mi><mn>3</mn></msub></mrow></math> as a lead-free alternative to commonly used cubic MHPs, while the sensitivity to crystal defects revealed here underlines the importance of defect control for obtaining robust devices with reliable properties.\",\"PeriodicalId\":20545,\"journal\":{\"name\":\"Physical Review Materials\",\"volume\":\"99 1\",\"pages\":\"\"},\"PeriodicalIF\":3.1000,\"publicationDate\":\"2024-09-16\",\"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.8.093607\",\"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}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical Review Materials","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1103/physrevmaterials.8.093607","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}
Anisotropic mechanical behavior of cesium tin iodide perovskite subjected to uniaxial tension
Lead-based metal halide perovskites (MHPs) have wide-ranging applications as solar cells, field-effect transistors, diodes, and photodetectors. However, their poor stability and concerns about toxicity have enabled lead-free tin-based MHPs to emerge as a promising alternative. We utilize molecular dynamics (MD) simulations to investigate the anisotropic mechanical behavior of single-crystal cubic , a promising lead-free MHP, under uniaxial tension. Among the three investigated crystal orientations, [111] is found to be the strongest and to exhibit the highest ultimate strain while [100] is the weakest. While shear strain localization and amorphization precede fracture along [100], fracture directly follows strain localization along [110] and [111]. We also investigated the influence of a crystal defect, in the form of an embedded rectangular crack, on the anisotropic mechanical behavior of cubic . The presence of crystal defects is found to substantially reduce the anisotropy in mechanical properties, with very similar crack growth behavior and almost identical stress-strain response noted along starkly different crystal orientations of loading. Finally, the ultimate strengths and ultimate strains of cubic determined here are comparable to or higher than those of cubic and determined in prior MD-based investigations. Thus, our study supports the applicability of cubic as a lead-free alternative to commonly used cubic MHPs, while the sensitivity to crystal defects revealed here underlines the importance of defect control for obtaining robust devices with reliable properties.
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.