WS₂ with Controllable Layer Number Grown Directly on W Film

As a layered material with single/multi-atom thickness, two-dimensional transition metal sulfide WS₂ has attracted extensive attention in the field of science for its excellent physical, chemical, optical, and electrical properties. The photoelectric properties of WS₂ are even more promising than graphene. However, there are many existing preparation methods for WS₂, but few reports on its direct growth on tungsten films. Therefore, this paper studies its preparation method and proposes an innovative two-dimensional material preparation method to grow large-sized WS₂ with higher quality on metal film. In this experiment, it was found that the reaction temperature could regulate the growth direction of WS₂. When the temperature was below 950 °C, the film showed horizontal growth, while when the temperature was above 1000 °C, the film showed vertical growth. At the same time, through Raman and band gap measurements, it is found that the different thicknesses of precursor film will lead to a difference in the number of layers of WS₂. The number of layers of WS₂ can be controlled by adjusting the thickness of the precursor.