| AVS 63rd International Symposium & Exhibition | |
| 2D Materials Focus Topic | Tuesday Sessions |
| Session 2D+MI-TuM |
| Session: | Novel 2D Materials |
| Presenter: | Andrew Mannix, Northwestern University/Argonne National Lab. |
| Authors: | A.J. Mannix, Northwestern University/Argonne National Lab. B. Kiraly, Northwestern University/Argonne National Lab. J.D. Wood, Northwestern University M.C. Hersam, Northwestern University N.P. Guisinger, Argonne National Laboratory |
| Correspondent: | Click to Email |
As the lightest metalloid element, bulk boron exhibits great physical and chemical complexity. In contrast, atomic clusters of boron form simple planar and cage-like structures that resemble those of carbon. Theoretical studies suggest that nanostructured boron allotropes (e.g., nanotubes and sheets) should exhibit structures similar to atomic boron clusters. To date, however, boron nanostructures have been scarcely explored experimentally, partly due to difficulties in synthesis and the need for atomically pristine experimental conditions. Recently, we have reported the synthesis of two-dimensional boron sheets (i.e., borophenes) on a silver surface under ultra-high vacuum conditions [Science350, 1513–1516 (2015) ]. Atomic-scale scanning tunneling microscopy shows the growth of two distinct phases, both of which exhibit anisotropic, chain-like structures. We confirm that these sheets are planar, chemically distinct, and atomically thin through extensive ex situ characterization supported by first principles calculations. Furthermore, in situ scanning tunneling spectroscopy of the borophene sheets shows metallic characteristics consistent with theoretical predictions, in contrast to semiconducting bulk boron.