MoS2 synthesis

The synthesis of MoS2 nanosheets using a simple two-step additive-free growth technique is reported by direct sulfurization of metal oxide powders or films.

The synthesis of a large area (1 cm2) vertically aligned 2H-MoS2 nanosheets has been realized. This was achieved using a simple, two-step CVD technique without the use of any additional chemicals. By employing XPS, Raman spectroscopy, PL and STEM high-quality and high crystalline quality of the synthesized material was evidenced. The as-grown nanosheets show prominent PL. The thin MoS2 nanosheets (< 50 nm) show PL at 1.83 eV and thus exhibit an optical quality comparable to monolayer MoS2. The precursors quantity was found to be the key parameter to controlling the thickness and height of the MoS2 nanosheets [1].

Based on the experimental results, a plausible growth mechanism of MoS2 nanosheets is proposed. This efficient and a simple synthetic route used for synthesizing a large area MoS2 nanosheets can be applied as a general method for the synthesis of other transition metal dichalcogenides. The as-grown MoS2 nanosheets could be a very interesting material for numerous nanotechnological applications in catalysis, optoelectronics, and nanoelectronics fields.


Fig. 1.  MoS2 nanosheets grown on Si sample with dispersion and 25 mg of MoO3 by sulfurization using 150 mg S powders at 850°C for 30 min. (a), (b) and (c) SEM images with different magnification with in the insert of (b) a cross-section SEM image. (d) A typical Raman Spectrum.


 [1]  G. Deokar, D. Vignaud, R. Arenal, P. Louette, J.-F. Colomer, Nanotechnology 27 (2016) 075604.