| AVS 64th International Symposium & Exhibition | |
| 2D Materials Focus Topic | Thursday Sessions |
| Session 2D-ThP |
| Session: | 2D Materials Poster Session |
| Presenter: | Kwonjae Yoo, National Nanofab Center (KAIST), Republic of Korea |
| Authors: | K.J. Yoo, National Nanofab Center (KAIST), Republic of Korea I.S. Kang, National Nanofab Center (KAIST), Republic of Korea G. Kim, National Nanofab Center (KAIST), Republic of Korea M.S. Hyun, National Nanofab Center (KAIST), Republic of Korea Y.C. Park, National Nanofab Center (KAIST), Republic of Korea S. Lee, Korea Research Institute of Standards and Science, Republic of Korea C. Hwang, Korea Research Institute of Standards and Science, Republic of Korea |
| Correspondent: | Click to Email |
Two dimensional (2D) metal carbides (MC) are recently entered in a playground of 2D materials world. Unlike conventional 2D materials, such as graphene and transition metal chalcogenides, they has shown the unique properties of 2D metallic- and superconducting- state. Moreover, their high thermal and chemical stability due to covalent-ionic bonding between metal and carbide atoms can offer a great advantage for harsh environmental sensor applications.
2D MC are obtained by selective extraction method from ternary carbides or by recently chemical vapor deposition (CVD). While monolayer metal carbides known as MXenes which produced by selective extraction method have shown defects and surface terminations which affect their physical properties, CVD grown monolayer metal carbides such as Mo2C, W2C are known to have very low defects [1, 2]. This modified CVD method uses Cu foil on molybdenum foil with melted Cu and moly alloy surface near the temperature of the Cu melting point.
Here we present the CVD using Cu foil inside folded Mo foil for growing metal carbides. The folded Mo foil inside CVD quartz tube not only prevents from evaporation of melted Cu, but also provides uniform gas flow. These growth condition seem to be positive effect on the growth of large area and uniform monolayer metal carbides such as Mo2C and W2C. We investigated CVD grown monolayer Mo2C using electron back scattering diffraction (EDSD), tunneling electron microscopy (TEM), and low temperature electron transport. Growth results depending on Cu crystallographic orientation will be discussed.
References
1. Large-area high quality 2D ultrathin Mo2C superconducting crystals, Chuan Xu, et al. Nature materials, Vol. 14, (2015)1135-1142
2. Controlled growth of ultrathin Mo2C superconducting crystals on liquid Cu surface, Dechao Geng, etal., 2D Mater. 4 (2017)011012.