| AVS 65th International Symposium & Exhibition | |
| 2D Materials Focus Topic | Monday Sessions |
| Session 2D+EM+MI+NS+TF-MoM |
| Session: | 2D Materials Growth and Fabrication |
| Presenter: | Kai Xiao, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory |
| Authors: | K. Xiao, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory X. Li, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory X. Sang, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory W. Zhao, Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS), Ulsan,44919, South Korea J. Dong, Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS), Ulsan,44919, South Korea A. Purektzy, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory C. Rouleau, Center for Functional Nanomaterials Brookhaven National Laboratory F. Ding, Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS), Ulsan,44919, South Korea R.R. Unocic, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory D.B. Geohegan, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory |
| Correspondent: | Click to Email |
Understanding the atomistic mechanisms governing the growth and etching of two-dimensional (2D) materials is of great importance in guiding the synthesis of large area, single-crystalline, high quality 2D crystals and heterostructures. In this talk, the growth-etching-regrowth process of monolayer 2D crystals by a CVD method will be discussed. We found that switching from growth to etching formed pores with various shapes in the single crystal domains which can be explained by edge-structure dependent growth process. In addition, combined with first principles theory, and ab initio simulations, in situ STEM imaging was used to understand the evolution of edge structure around pores in monolayers as a function of temperature and Mo chemical potential. Our results demonstrate that by varying the local chemical environment, we can trigger formation of 2D monolayer nanostructures terminated by different edge reconstructions during in situ heating and electron beam irradiation and form edge structures with metallic and/or magnetic properties. The ability to synthesize 2D nanostructures with metastable NW edges having predictable atomic structures opens the door to a wide range of novel 2D materials and heterosturctures with electrical and magnetic properties as revealed by DFT, which could potentially act as functional building blocks for next-generation nano-devices.
References:
[1] X. Li, J. Dong, J. C. Idrobo, A. A. Puretzky, C. M. Rouleau, D. B. Geohegan, F. Ding, K. Xiao, J. Am. Chem. Soc. 139, 482 (2017).
[2] X. Sang, X. Li, W. Zhao, J. Dong, C. M. Rouleau, D. B. Geohegan, F. Ding, K. Xiao, R. R. Unocic, Nature Comm. Accepted (2018).
Acknowledgement: Synthesis science sponsored by the Materials Science and Engineering Division, Office of Basic Energy Sciences, U.S. Department of Energy. Characterization science performed at the Center for Nanophase Materials Sciences, which is a DOE Office of Sciences User Facility.