Sulfur Hexafluoride (SF₆) is most often prepared in specified quantities via the direct fluorination of high-purity sulfur.
Sulfur Hexafluoride's reasonably high density and inactivity pretty much cements its appliance as an electrical insulator in high-voltage transformers, transmission lines, and microwave antennas. It has found further use as an insulating gas in double-windowpane glass. Being a high-density inert gas can prove as much of a limitor for SF6 as it is a strength; its Global Warming Potential (GWP) is considered problematic. As such, research is now actively in play to find an environmentally safer choice to minimize its use. For the time being, it remains widely regarded as the preferred insulator in high-voltage applications, but it should be used cautiously and taken back for reclamation instead of just vented during equipment repair.
High-purity Sulfur Hexafluoride is used extensively as an etchant in semiconductor assembly, as a manageable source of fluorine.