Modification of Soft Inorganic Thin Films through the use of van der Waals Epitaxial Strain

通过使用范德华外延应变对软无机薄膜进行改性

• 批准号: 1635520
• 负责人: Jian Shi
• 金额: $ 37.92万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1635520&HistoricalAwards=false
• 关键词: Modification; Soft; Inorganic; Thin; Films

Human society's consistent pursuit of better means of information communication and effective use of it?s energy supplies, requires continual innovation in the underlying technological materials infrastructure. Transformative technologies rely on breakthroughs in their scientific foundations, such as materials and processing. Recently, a number of soft inorganic solids have shown potential for applications in energy conversion and information manipulation, and promising new insight into the physics of exotic states of matter. Theoretical works suggest that reversible mechanical deformations in these materials could lead to either gradual or abrupt shifts of their physical properties. However, these soft materials, particularly, heavy halides and chalcogenides, experience difficulty in utilizing conventional chemical approaches to induce for deformation purpose due to their unique materials structures and atomic arrangement. This work addresses this problem by exploring the possibility of stretching soft but heavy halide and chalcogenide materials through van der Waals epitaxy. The research will introduce a new set of useful optoelectronic, electro-optic, logic and memory materials in the form of strained thin films. Researchers will also pursue educational goals by establishing a 'Graphics for Learning' program, which will train engineering undergraduate students, especially from underrepresented groups, through the graphical presentation of information. Strain within epitaxial electronic and optical materials has been used to produce desirable materials properties unachievable in the unstrained state. While used to great effect in conventional semiconductors, the introduction of strain into the class of van der Waals bonded compounds has been difficult. The van der Waals compounds formed from elements deeper in the periodic table, termed heavy halides and chalcogenides, may offer new opportunity to strain-modify these materials. This grant looks to synthesize 'soft' and 'heavy' materials as thin films out of the heavier elements via van der Waals epitaxy onto useful substrates under conditions that lead to significant elastic strains within the epitaxial layers. The focus will be on two model materials: the van der Waals solid PbI2 and non-van der Waals solid CH3NH3PbCl3. Several other materials including CdTe, CdS, SbI3 and Sb2S3 will also be studied. The strain magnitude, strain relaxation mechanisms and strain-induced physical properties will be characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy and angle-resolved photoluminescence spectroscopy. First-principle calculations will be employed to elucidate the experimental observations. After establishing a van der Waals nucleation/growth model for halides and chalcogenides, modifications to the synthesis of these epitaxial materials will be directed at achieving elastic strain engineering via the van der Waals epitaxial process. The magnitude and anisotropy of the epitaxial strain and the effect on materials properties will be used to develop a mechanistic understanding of the underlying changes in and behavior of the epitaxial 'heavy' van der Waals materials.

人类社会始终如一地追求更好的信息通信和有效利用该能源的能源，需要在基础技术材料基础设施中持续创新。变革性技术依赖于其科学基础中的突破，例如材料和加工。最近，许多软无机固体显示出在能量转换和信息操纵中应用的潜力，并有望对异国物质物理的物理学有新的见解。理论工作表明，这些材料中可逆的机械变形可能导致其物理特性的逐渐或突然转移。但是，这些柔软的材料，尤其是重型卤化物和葡萄干剂，由于其独特的材料结构和原子布置，使用常规化学方法诱导变形目的而遇到困难。这项工作通过探索通过范德华同际拉伸柔软但重卤化物和墨西哥乳酸元素材料的可能性来解决此问题。这项研究将以紧张的薄膜形式引入一套新的有用的光电，电形，逻辑和记忆材料。研究人员还将通过建立“学习图形”计划来实现教育目标，该计划将通过信息的图形介绍来培训工程本科生，尤其是来自代表性不足的群体的学生。 外延电子和光学材料内的应变已用于在未经培训状态下产生无法发现的理想材料特性。虽然在常规半导体中使用了很大的作用，但很难将应变引入范德华键合成的化合物类别。范德华的化合物由元素周期表中更深的元素形成的化合物称为重卤化物和辣椒剂，可能会提供新的机会来扭伤这些材料。该赠款旨在将“软”和“重”材料合成为薄膜从较重的元素中，通过范德华同际，在有用的底物上，在导致外延层内有明显的弹性菌株的情况下。焦点将放在两种模型材料上：范德华固体PBI2和非van der der waals实心CH3NH3PBCl3。还将研究其他几种其他材料，包括CDTE，CDS，SBI3和SB2S3。应变幅度，应变弛豫机制和应变诱导的物理特性的特征是X射线衍射，拉曼光谱，透射电子显微镜和角度分辨的光致发光光谱。将使用第一原则计算来阐明实验观察。在建立了卤化物和辣椒剂的范德华成核/生长模型之后，对这些外延材料合成的修改将致力于通过范德华的外延过程实现弹性应变工程。外延菌株的大小和各向异性以及对材料特性的影响将用于对外在“重型”范德华材料的潜在变化和行为产生机械理解。

项目成果

Effect of strain on the Curie temperature and band structure of low-dimensional SbSI

应变对低维SbSI居里温度和能带结构的影响

• DOI: 10.1063/1.5017490
• 发表时间: 2018
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: Wang, Yiping;Hu, Yang;Chen, Zhizhong;Guo, Yuwei;Wang, Dong;Wertz, Esther A.;Shi, Jian
• 通讯作者: Shi, Jian

Van Der Waals Hybrid Perovskite of High Optical Quality by Chemical Vapor Deposition

• DOI: 10.1002/adom.201700373
• 发表时间: 2017-11-02
• 期刊: ADVANCED OPTICAL MATERIALS
• 影响因子: 9
• 作者: Chen, Zhizhong;Wang, Yiping;Shi, Jian
• 通讯作者: Shi, Jian

van der Waals epitaxy of CdTe thin film on graphene

• DOI: 10.1063/1.4964127
• 发表时间: 2016-10
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: D. Mohanty;W. Xie;Yiping Wang;Zonghuan Lu;Jian Shi;Shengbai Zhang;Gwo-Ching Wang;T. Lu;I. Bhat

Surface and interface of epitaxial CdTe film on CdS buffered van der Waals mica substrate

• DOI: 10.1016/j.apsusc.2017.03.260
• 发表时间: 2017-08
• 期刊: Applied Surface Science
• 影响因子: 6.7
• 作者: Y. -. Yang;Lucas J. Seewald;D. Mohanty;Yiping Wang;L. H. Zhang;K. Kisslinger;W. Xie;Jian Shi;I. Bhat;Shengbai Zhang;T. Lu;Gwo-Ching Wang

van der Waals epitaxial ZnTe thin film on single-crystalline graphene

• DOI: 10.1063/1.5011941
• 发表时间: 2018-01
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: Xin Sun;Zhizhong Chen;Yiping Wang;Zonghuan Lu;Jian Shi;Morris Washington;T. Lu