@article{Yang2017, 
author = {Sang Yoon Yang and Gi Woong Shim and Seung-Bum Seo and Sung-Yool Choi},
title = {Effective shape-controlled growth of monolayer MoS2 flakes by powder-based chemical vapor deposition},
year = {2017},
journal = {Nano Research},
volume = {10},
number = {1},
pages = {255-262},
keywords = {molybdenum disulfide, shape evolution, CVD growth, diagram, growth condition},
url = {https://www.sciopen.com/article/10.1007/s12274-016-1284-6},
doi = {10.1007/s12274-016-1284-6},
abstract = {In the recent years, transition-metal dichalcogenides such as MoS2 have attracted considerable attention owing to their unique structure and electronic properties. Chemical vapor deposition (CVD) is a popular method for producing MoS2 flakes with different shapes. Here, we report an effective method for achieving a broad range of shape evolution in CVD-grown monolayer MoS2 flakes. By controlling the S and MoO3 temperatures, the shape of the monolayer MoS2 flakes was varied from hexagonal to triangular via intermediate shapes such as truncated and multi-apex triangles. The shape evolution of the MoS2 flakes can be explained by introducing the term "nominal Mo: S ratio", which refers to the amount of loaded MoO3 and evaporated S powders. By using the nominal Mo: S ratio, we predicted the potential reaction atmosphere and effectively controlled the actual proportion of MoO3−x with respect to S in the growth region, along with the growth temperature. From the systematic investigation of the behavior of the shape evolution, we developed a shape-evolution diagram, which can be used as a practical guide for producing CVD-grown MoS2 flakes with desired shapes.}
}