MOCVD Growth of Hierarchical Nanostructured MoS2: Implications for Reactive States as the Large-Area Film

Large-area hierarchical grown transition metal dichalcogenide(TMD)nanostructures as out-of-plane directional layered TMD nanocrystalson a substrate could be considerably useful in electrochemical applicationsbecause of the high density of edge states. In this study, layeredMoS(2) nanocrystals less than 50 nm in diameter were synthesizedby overlapping with each other as vertical growth in the form of afilm with an area of 10 mm x 40 mu m using metal-organicchemical vapor deposition (MOCVD) for the lateral growth of TMDs.Notably, in the spatial distribution, a singular point where the verticalgrowth is promoted was found through optical dark-field data and spatiallyresolved micro-Raman spectroscopy. The accelerated vertical growthregion distinguished by the singular point is due to the layer-dependentdielectric constant of MoS2, which affects the surfaceenergy and changes the conditions of vapor-phase deposition. In addition,with these phenomena, we discuss a way for expanding the hierarchicalvertically grown MoS2 region on a substrate through analyticalmethods based on hydromechanics.

Automated summary

In this study, large-area hierarchical transition metal dichalcogenide (TMD) nanostructures were grown vertically on a substrate, showing potential for electrochemical applications due to their high density of edge states. A singular point promoting vertical growth was identified through optical dark-field data and micro-Raman spectroscopy, attributed to the layer-dependent dielectric constant of MoS2. Furthermore, a method for expanding the vertically grown MoS2 region on a substrate was discussed using analytical methods based on hydromechanics.