Chemical vapor deposition of trigonal prismatic NbS2 monolayers and 3R-polytype few-layers.

Group VB transition-metal dichalcogenides (TMDs) have an intriguing structure-dependent charge density wave and superconductivity. Here, we report the direct chemical vapor deposition of large-size NbS2 monolayers and few-layers with trigonal prismatic coordination and 3R polytype layer-layer stacking on hexagonal boron nitride (h-BN). The structure has been confirmed by micro-Raman spectroscopy and atomic-resolution scanning transmission electron microscopy (STEM).