Direct Epitaxial Synthesis of Selective Two-Dimensional Lateral Heterostructures

• Published in: ACS nano Vol. 13; no. 11; pp. 13047 - 13055
• Main Authors: Lee, Juwon, Pak, Sangyeon, Lee, Young-Woo, Park, Youngsin, Jang, A-Rang, Hong, John, Cho, Yuljae, Hou, Bo, Lee, Sanghyo, Jeong, Hu Young, Shin, Hyeon Suk, Morris, Stephen M, Cha, SeungNam, Sohn, Jung Inn, Kim, Jong Min
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 26.11.2019
• Subjects: one-pot CVD synthesis; growth parameters; 2D heterostructure; Mo1−x W x S2 alloy; supersaturation level; core−shell structure; Mo1−xWxS2 alloy
• DOI: 10.1021/acsnano.9b05722
• ISSN: 1936-0851; 1936-086X

Two-dimensional (2D) heterostructured or alloyed monolayers composed of transition metal dichalcogenides (TMDCs) have recently emerged as promising materials with great potential for atomically thin electronic applications. However, fabrication of such artificial TMDC heterostructures with a sharp interface and a large crystal size still remains a challenge because of the difficulty in controlling various growth parameters simultaneously during the growth process. Here, a facile synthetic protocol designed for the production of the lateral TMDC heterostructured and alloyed monolayers is presented. A chemical vapor deposition approach combined with solution-processed precursor deposition makes it possible to accurately control the sequential introduction time and the supersaturation levels of the vaporized precursors and thus reliably and exclusively produces selective and heterogeneous epitaxial growth of TMDC monolayer crystals. In addition, TMDC core/shell heterostructured (MoS2/alloy, alloy/WS2) or alloyed (Mo1–x W x S2) monolayers are also easily obtained with precisely controlled growth parameters, such as sulfur introduction timing and growth temperature. These results represent a significant step toward the development of various 2D materials with interesting properties.