Wang Qi-Bo, Xu Qin-Qin, Yang Ming-Zhe, Wu Zhong-Shuai, Xia Xiao-Chuan, Yin Jian-Zhong, Han Zhen-Hua
State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, 2 Ling Gong Road, 116024 Dalian, China.
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, 116024 Dalian, China.
ACS Appl Mater Interfaces. 2023 Apr 5;15(13):17396-17405. doi: 10.1021/acsami.3c01407. Epub 2023 Mar 23.
In this study, a novel pressure-induced supercritical phase nucleation method is proposed to synthesize monolayer MoS films, which is promoter free and can avoid contamination of films derived from these heterogeneous promoters in most of the existing techniques. The low-crystallinity and size-controlled MoO(acac) particles are recrystallized on the substrate via the pressure-sensitive solvent capacity of supercritical CO and these particles are used as growth sites. The size of single-crystal MoS on the substrate is found to be dependent on the wetting area of the pyrolyzed precursor droplets (MoO) on the surface, and the formation of continuous films with high coverage is mainly controlled by the coalescence of MoO droplets. It is enhanced by the increase of the nucleation site density, which can be adjusted by the supersaturation of the supercritical fluid solution. Our findings pave a new way for the controllable growth of MoS and other two-dimensional materials and provide sufficient and valuable evidence for vapor-liquid-solid growth.
在本研究中，提出了一种新型的压力诱导超临界相成核方法来合成单层MoS薄膜，该方法无需促进剂，并且在大多数现有技术中可以避免由这些异质促进剂导致的薄膜污染。低结晶度且尺寸可控的MoO(acac)颗粒通过超临界CO的压敏溶剂容量在基底上重结晶，并且这些颗粒被用作生长位点。发现基底上单晶MoS的尺寸取决于热解前驱体液滴（MoO）在表面上的润湿面积，并且具有高覆盖率的连续薄膜的形成主要由MoO液滴的聚结控制。它通过成核位点密度的增加而增强，而成核位点密度可以通过超临界流体溶液的过饱和度来调节。我们的研究结果为MoS和其他二维材料的可控生长开辟了一条新途径，并为气-液-固生长提供了充分且有价值的证据。
