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Materials Science Research Lecture

Tuesday, May 29, 2018
4:00pm to 5:00pm
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Spalding Laboratory 106 (Hartley Memorial Seminar Room)
Atom-by-Atom Engineering with 2D Materials
Andrew Mannix, Postdoctoral Fellow, University of Chicago,

Abstract: Materials engineered with atomic precision promise unprecedented control over structure and properties. Atomically thin two-dimensional (2D) materials, which individually exhibit superlative characteristics, can be grown, patterned, and stacked on an atom-by-atom basis to realize such designer solids. In this talk, I will discuss two steps towards this goal: the growth of entirely synthetic 2D allotropes and the automated fabrication of 2D layers into stacked heterostructures.

To date, the study of 2D materials has focused on structures derived from a limited library of bulk, layered solids (e.g., graphene from graphite). However, the growth of entirely synthetic 2D materials—those without bulk analogues—dramatically expands our capability to develop materials with new structures and novel properties. To illustrate this point, I will present the synthesis of 2D boron sheets (i.e., borophene), which were grown on a silver surface under ultra-high vacuum conditions. Atomic-scale imaging shows that borophene exhibits anisotropic structures unlike any bulk boron allotrope, while multiple techniques confirm that the borophene sheets are a synthetic analogue to graphene (i.e., atomically thin and chemically discrete). Moreover, unlike semiconducting bulk boron, borophene shows metallic characteristics. This systematic approach towards new 2D materials discovery can be generalized to explore a variety of elemental and compound structures which cannot be realized in bulk-derived layered crystals.

This concept can also be extended to the third dimension by stacking 2D materials into extended van der Waals solids with functionality embedded in the atomic-scale order of the material. Toward this end, I will discuss the automated microfabrication of stacked 2D heterostructures under vacuum conditions.

About the speaker: Andrew Mannix earned his B.S. in Materials Science and Engineering at the University of Illinois at Urbana-Champaign and his Ph.D. in Materials Science and Engineering at Northwestern University. His graduate work explored the growth and atomic-scale characterization of synthetic 2D materials. He is currently a Kadanoff-Rice Postdoctoral Fellow in the James Franck Institute at the University of Chicago, where he works on new methods of atomically-thin nanomaterials growth, processing, and assembly.

For more information, please contact Jennifer Blankenship by phone at 626-395-8124 or by email at [email protected].