Fig. 4: Dynamic effect on SCVLS method.

a Schematic of the timing of introducing sulfur vapor affecting the final growth product. b When sulfur vapor was introduced early, the Na₂Mo₂O₇ precursor rapidly formed the MoS₂ seed layer when exposed on the surface (left). When sulfur vapor was introduced later, the MoS₂ seed layer was formed at the solid–liquid interface, thus leaving a droplet of the liquid precursor on top of the interface. This droplet was later sulfurized into the second layer of MoS₂ (right). Optical images of the transferred c monolayer, d bilayer, and e trilayer MoS₂. Scale bars are 50 µm. f Raman and g photoluminescence spectra of the monolayer, bilayer, and trilayer MoS₂.