Synthesis of flower-like WS₂ by chemical vapor deposition*

Abstract

Flower-like tungsten disulfide (WS2) with a diameter of 5–10 μm is prepared by chemical vapor deposition (CVD). Scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), Raman spectroscopy, and ultraviolet-visible (UV-vis) spectroscopy are used to characterize its morphological and optical properties, and its growth mechanism is discussed. The key factors for the formation of flower-like WS2 are determined. Firstly, the cooling process causes the generation of nucleation dislocations, and then the “leaf” growth of flower-like WS2 is achieved by increasing the temperature.

Molten glass-mediated conditional CVD growth of MoS2 monolayers and effect of surface treatment on their optical properties

“…To stabilize gas flow, control S vaporization, and maintain a clean environment with minimal contamination, the alumina boat containing precursors and substrates was enclosed in a smaller quartz tube with a diameter of 2 cm, suspended within the outer quartz tube of the CVD system with a diameter of 5.0 cm. Refractive holders were employed for thermal stabilization inside the inner tube [32]. Our process is optimized for three substrates with lateral sizes of 1 cm × 1 cm, one of which is a SiO 2 /Si substrate, and the other two are glasses on graphite foil at the same plane.…”