Controlled CVD fabrication of T-VS2 nanosheets on oxide supports

Two-dimensional (2D) T-phase vanadium disulfide (T-VS 2 ), with its intrinsic ferromagnetism, semi-metallicity, and considerable chemical activity, holds great potential for a variety of applications in catalysis, device integration, and energy storage. However, research on the controlled growth of 2D T-VS 2 has remained limited, particularly deficient in phase control, thickness engineering, and crystallinity optimization. In this study, we systematically explore the influence of growth parameters of a chemical vapor deposition (CVD) method on the synthesis of T-VS 2 nanosheets. Specifically, we observe that properly lowering the growth temperature can facilitate the increase in sheet size, increasing the vanadium precursor concentration effectively manipulates the thickness of the T-VS 2 nanosheets, and prolonged reaction time leads to flipping of the nanosheets. What’s more, the morphology control of T-VS 2 is influenced by temperature, V source supply, and H 2 supply, leading to transitions between trapezoidal, truncated triangular, and hexagonal shapes. By carefully balancing these key parameters, a controllable growth strategy for T-VS 2 can be established. These results are drawn from the growth study on an atomically smooth SrTiO 3 (100) substrate and validated further on the Al 2 O 3 (0001) surface, which registers its scalability and generalizability and hence provides a foundation for the construction of various T-VS 2 -based nanostructures or nanodevices.