CVD Grown MoS2 Nanoribbons on MoS2 Covered Sapphire(0001) Without Catalysts

Abstract

One‐dimensional (1D) atomically thin crystals have attracted considerable interest due to their unique properties and potential applications. Herein, the chemical vapor deposition (CVD) growth of molybdenum disulfide (MoS2) nanoribbons on sapphire(0001) supported monolayer MoS2 flakes without catalysts as well as the characterizations by means of Raman and photoluminescence (PL) spectroscopy, optical microscopy (OM), atomic force microscopy (AFM), and scanning transmission electron microscopy (STEM). The Raman and PL results is reported, as well as OM images reveal that such MoS2 nanoribbons grow on monolayer MoS2 flakes. STEM and selected area electron diffraction (SAED) results reveal that they are grown along the ⟨101⎯⎯0⟩ direction with atomically sharp edges. Controlled experiments show that the deficiency of sulfur vapor at the beginning of growth induced 1D MoOxS2−x crystals as precursors. The subsequent sulfurization changes them into MoS2 nanoribbons. These findings provide a facile approach to MoS2 nanoribbons and enrich the horizon of the preparation of nanostructured transition metal dichalcogenides.