Morphological Evolution of Vertically Standing Molybdenum Disulfide Nanosheets by Chemical Vapor Deposition

Abstract

In this study, we demonstrated the chemical vapor deposition (CVD) of vertically standing molybdenum disulfide (MoS2) nanosheets, with an unconventional combination of molybdenum hexacarbonyl (Mo(CO)6) and 1,2-ethanedithiol (C2H6S2) as the novel kind of Mo and S precursors respectively. The effect of the distance between the precursor’s outlet and substrates (denoted as d) on the growth characteristics of MoS2, including surface morphology and nanosheet structure, was investigated. Meanwhile, the relationship between the structure characteristics of MoS2 nanosheets and their catalytic performance for hydrogen evolution reaction (HER) was elucidated. The formation of vertically standing nanosheets was analyzed and verified by means of an extrusion growth model. The crystallinity, average length, and average depth between peak and valley (Rz) of MoS2 nanosheets differed depending on the spatial location of the substrate. Good crystalized MoS2 nanosheets grown at d = 5.5 cm with the largest average length of 440 nm, and the highest Rz of 162 nm contributed to a better HER performance, with a respective Tafel slope and exchange current density of 138.9 mV/decade, and 22.6 μA/cm2 for raw data (127.8 mV/decade and 19.3 μA/cm2 for iR-corrected data).

Strategy and Future Prospects to Develop Room-Temperature-Recoverable NO2 Gas Sensor Based on Two-Dimensional Molybdenum Disulfide

“…These facilities make MoS 2 compatible for gas-sensing application [ 100 ]. The low binding energy of 6.1 and 13.9 eV is needed to create S and Mo vacancies, respectively, which can turn the edges of MoS 2 flakes into metallic sites [ 101 , 102 ]. MoS 2 has a tunable bandgap compared to graphene which increases the overall sensing performance of MoS 2 film [ 103 ].…”

Role of Surface Processes in Growth of Monolayer MoS2: Implications for Field-Effect Transistors

“…While considerable progress has been made in the synthesis of 2D materials, optimization of growth to obtain the desired microstructure has been a very empirical one. , Though physicochemical models of graphene growth have now been reported, − there have been very few recent reports for more complicated systems such as MoS 2 and other transition metal chalcogenides such as WSe 2 and WS 2 . In an earlier paper, we had studied the effect of pressure on the nucleation and growth of MoS 2 domains by a CVD method in which Mo­(CO) 6 and H 2 S were used as the precursors for Mo and S. Recent reports ,,− for various vapor deposition techniques testify that this chemistry is getting popular for growth of sulfides and selenides of both Mo and W.…”

Computational Fluid Dynamics Insights into Chemical Vapor Deposition of Homogeneous MoS2 Film with Solid Precursors

“…The effect of CVD parameters on the quality of TMD flakes and films have been investigated such as growth temperature, carrier gas flow rate, substrate orientations, pressure and position of precursors. [ 13 − 16 ] These experimental approaches require considerable amount of resources and are highly dependent on post‐growth analyses. Besides, in‐situ monitoring is often expensive and difficult to be implemented in a CVD system.…”