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

University Of Oregon Eugene, Eugene OR

Investigators

Abstract

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.