Open AccessAtomistic mechanisms of seeding promoter-controlled growth of molybdenum disulphide
Author(s) -
Heedong Ko,
Han Seul Kim,
Muhammad Ramzan,
Seongjae Byeon,
Soo Ho Choi,
Ki Kang Kim,
YongHoon Kim,
Soo Min Kim
Publication year - 2019
Publication title -
2d materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.702
H-Index - 72
ISSN - 2053-1583
DOI - 10.1088/2053-1583/ab4cd4
Subject(s) - seeding , monolayer , nucleation , adsorption , substrate (aquarium) , molybdenum , molybdenum disulfide , materials science , chemical vapor deposition , crystallography , chemical engineering , chemistry , polar , chemical physics , nanotechnology , inorganic chemistry , organic chemistry , physics , thermodynamics , oceanography , astronomy , geology , engineering , metallurgy
Seeding promoters facilitate the nucleation and growth of transition metal dichalcogenides in chemical vapor deposition (CVD). However, sophisticated roles of seeding promoter remain unclear. Here, adopting triangular-shaped crystal violet (CV) consisting of nonpolar and polar parts as the seeding promoter, we study the role of seeding promoter for the growth of molybdenum disulfide (MoS 2 ). We systematically control the geometrical configuration of CV on SiO 2 /Si substrate by changing the solvent polarity and find that it strongly affects the growth of monolayer or multilayer MoS 2 domains via CVD. Monolayer MoS 2 domains were predominantly grown on randomly lying-down CV configurations on SiO 2 /Si substrate, whereas multilayer MoS 2 domains are synthesized at concentrated polar parts in CV micelle on the substrate. Density functional theory calculations reveal that the initial nucleation step for the MoS 2 growth is the adsorption of S on CV and the most favourable S adsorption site is the polar part in CV. Furthermore, it is found that the CV adsorption to SiO 2 is mediated by the polar CV part and additionally strengthened in the lying-down CV configuration. Enhancing the thermal stability as well as hindering the re-aggregation of CV at high temperature, the lying down CV configuration allows the predominant growth of monolayer MoS 2 . This work provides a general framework to understand the growth of MoS 2 from aromatic seeding promoters.