Li Shisheng, Lin Yung-Chang, Zhao Wen, Wu Jing, Wang Zhuo, Hu Zehua, Shen Youde, Tang Dai-Ming, Wang Junyong, Zhang Qi, Zhu Hai, Chu Leiqiang, Zhao Weijie, Liu Chang, Sun Zhipei, Taniguchi Takaaki, Osada Minoru, Chen Wei, Xu Qing-Hua, Wee Andrew Thye Shen, Suenaga Kazu, Ding Feng, Eda Goki
Centre for Advanced 2D Materials, National University of Singapore, Singapore, Singapore.
Department of Physics, National University of Singapore, Singapore, Singapore.
Nat Mater. 2018 Jun;17(6):535-542. doi: 10.1038/s41563-018-0055-z. Epub 2018 Apr 23.
Chemical vapour deposition of two-dimensional materials typically involves the conversion of vapour precursors to solid products in a vapour-solid-solid mode. Here, we report the vapour-liquid-solid growth of monolayer MoS, yielding highly crystalline ribbons with a width of few tens to thousands of nanometres. This vapour-liquid-solid growth is triggered by the reaction between MoO and NaCl, which results in the formation of molten Na-Mo-O droplets. These droplets mediate the growth of MoS ribbons in the 'crawling mode' when saturated with sulfur. The locally well-defined orientations of the ribbons reveal the regular horizontal motion of the droplets during growth. Using atomic-resolution scanning transmission electron microscopy and second harmonic generation microscopy, we show that the ribbons are grown homoepitaxially on monolayer MoS with predominantly 2H- or 3R-type stacking. Our findings highlight the prospects for the controlled growth of atomically thin nanostructure arrays for nanoelectronic devices and the development of unique mixed-dimensional structures.
二维材料的化学气相沉积通常涉及以气-固-固模式将气相前驱体转化为固体产物。在此，我们报道了单层MoS₂的气-液-固生长，得到了宽度从几十纳米到几千纳米的高度结晶的带材。这种气-液-固生长是由MoO₃与NaCl之间的反应引发的，该反应导致形成熔融的Na-Mo-O液滴。当这些液滴被硫饱和时，它们以“爬行模式”介导MoS₂带材的生长。带材局部明确的取向揭示了生长过程中液滴有规律的水平运动。利用原子分辨率扫描透射电子显微镜和二次谐波产生显微镜，我们表明这些带材在单层MoS₂上以主要为2H或3R型堆叠的方式同质外延生长。我们的发现突出了为纳米电子器件可控生长原子级薄纳米结构阵列以及开发独特的混合维度结构的前景。
