Synthesis of Large-Scale Single-Crystalline Monolayer WS(2) Using a Semi-Sealed Method

As a two-dimensional semiconductor, WS(2) has attracted great attention due to its rich physical properties and potential applications. However, it is still difficult to synthesize monolayer single-crystalline WS(2) at larger scale. Here, we report the growth of large-scale triangular single-crystalline WS(2) with a semi-sealed installation by chemical vapor deposition (CVD). Through this method, triangular single-crystalline WS(2) with an average length of more than 300 µm was obtained. The largest one was about 405 μm in length. WS(2) triangles with different sizes and thicknesses were analyzed by optical microscope and atomic force microscope (AFM). Their optical properties were evaluated by Raman and photoluminescence (PL) spectra. This report paves the way to fabricating large-scale single-crystalline monolayer WS(2), which is useful for the growth of high-quality WS(2) and its potential applications in the future.