Sulfurization of WO3 nanorods into WS2 as a function of H2S/Ar partial pressure

Core-shell WO3/WS2 nanorods with varying shell thickness are synthesized using plasma assisted sulfurization process and the effect of partial pressure (Pp) of H2S/Ar on sulfurization of WO3 is studied. HR-TEM analysis shows that the maximum shell thickness is obtained at optimum Pp value of 6.5×10-1 Torr. Raman and XRD analysis depicts that monoclinic WO3 is converted into hexagonal phase of WS2. SEM shows no change in the morphology of WO3 nanorods after sulfurization process. This study shows that shell of WS2 can be controlled via controlling the partial pressure value. This study shows new process for controlled synthesis of tungsten-oxide/sulfide core-shell nanostructures.