Synthesis, Properties and Structure-Function Relationships in Ferecrystals: New Compounds Composed of Stacked 2D Layers with Designed Nanoarchitecture

摘要：制备具有设计性能的新型化合物是材料研究的一大挑战。用复杂的分层方案创造稳定的分层材料的能力提供了前所未有的能力来探测结构、组成和成分的物理性质之间的相互作用。这项研究产生了丰富的新材料集合，具有多样化和高度不寻常的性质，并提高了对含有结构不同层的化合物的结构-性质关系的理解。目标是了解物理性质对各层的身份、厚度和顺序的依赖性。第二个目标是了解合成方法的基本方面，从而制备稳定的产物。当前和未来的技术对国际竞争力至关重要，取决于能够制备和表征稳定的层状材料，以获得任何单个组件都无法获得的增强性能。技术摘要：本研究扩展了一种合成方法，以创建包含两种或更多结构不同成分的新型层状固体，它们之间具有原子突变界面。设计的前驱体能够在大面积上制备具有设计纳米结构的动力学稳定异质结构。该项目的目标是了解在包含电隔离的过渡金属二硫族化合物、铋硫族化合物和相关三元结构的二维层的异质结构中，输运性质对纳米结构的依赖。不同厚度的大带隙间隔层电隔离了二硫化物单层，相邻的磁层用于扰动单层。这项研究是及时的，因为最近的发现承诺了各种技术的进步，包括隧道晶体管，柔性电子，光电探测器，光伏和具有前所未有的特性和/或独特功能的发光器件。这项研究为研究生在沉积技术、薄膜表征技术和二维异质结构中发生的物理现象方面提供了广泛的技术背景。这种培训使他们能够在高科技行业，学术界或国家实验室的职业生涯中茁壮成长。

Non-technical Abstract:A grand challenge in materials research is the preparation of novel compounds with designed properties. The ability to create stable layered materials with complicated layering schemes provides an unprecedented ability to probe the interplay between structure, composition, and physical properties of the constituents. This research produces a rich collection of new materials with diverse and highly unusual properties and an improved understanding of structure-property relationships in compounds containing structurally different layers. A goal is to understand the dependence of physical properties on the identity, thickness, and the sequence of individual layers. A second goal is to understand the fundamental aspects of the synthesis approach that result in the preparation of stable products. Current and future technologies crucial to international competitiveness depend on being able to both prepare and characterize stable layered materials to obtain enhanced properties, which are not found in any of the individual components. Technical Abstract:This research extends a synthesis approach to create new, layered solids containing two or more structurally different constituents with atomically abrupt interfaces between them. Designed precursors enable kinetically stable heterostructures with designed nanoarchitectures to be prepared over large areas. The project goal is to understand the dependence of transport properties on nanoarchitecture in heterostructures containing electrically isolated two dimensional layers of transition metal dichalcogenides, bismuth chalcogenides and related ternary structures. Large band gap spacer layers of varying thickness electrically isolate the dichalcogenide monolayers and adjacent magnetic layers are used to perturb the monolayers. This research is timely, as recent discoveries promise advances in a variety of technologies including tunnelling transistors, flexible electronics, photodetectors, photovoltaics and light-emitting devices with unprecedented characteristics and/or unique functionalities. This research provides a broad technical background for graduate students in deposition technologies, thin film characterization techniques, and physical phenomena that occur in 2D heterostructures. This training enables them to thrive in careers in high tech industries, academia or national laboratories.