Large-scale synthesis of NbS2nanosheets with controlled orientation on graphene by ambient pressure CVD

Abstract

We report ambient pressure chemical vapor deposition (CVD) growth of single-crystalline NbS₂ nanosheets with controlled orientation. On Si and SiO₂ substrates, NbS₂ nanosheets grow almost perpendicular to the substrate surface. However, when we apply transferred CVD graphene on SiO₂ as a substrate, NbS₂ sheets grow laterally lying on the graphene. The NbS₂ sheets show the triangular and hexagonal shapes with a thickness of about 20–200 nm and several micrometres in the lateral dimension. Analyses based on X-ray diffraction and Raman spectroscopy indicate that the NbS₂ nanosheets are single crystalline 3R-type with a rhombohedral structure of R3m space group. Our findings on the formation of highly aligned NbS₂ nanosheets on graphene give new insight into the formation mechanism of NbS₂ and would contribute to the templated growth of various layered materials.