Synthesis of Molybdenum Disulfide Nanowire Arrays Using a Block Copolymer Template

A simple route for the synthesis of arrays of sub-20-nm-wide molybdenum disulfide (MoS2) nanowires using a self-assembled cylinder forming poly(styrene-b-2-vinylpyridine) thin films is demonstrated. The protonated 2-vinylpyridine selectively seeds molybdenum precursors in the aqueous solution, and the precursors are converted to molybdenum sulfide during a sulfur annealing process. An ultraviolet cross-linking step is introduced to ensure the successful transfer of the morphologies of the block copolymer templates to the MoS2 nanowires. The nanowires transition from an amorphous to a crystalline MoS2 phase upon thermal annealing in the presence of sulfur, as confirmed by X-ray photoelectron spectroscopy, Raman spectroscopy, X-ray diffraction, and transmission electron microscopy. This work provides a pathway to large area, dense, spatially localized arrays of transition metal dichalcogenide nanowires for catalytic and sensing applications.