Synthesis and Dielectric Properties of Trifluoromethanesulfonyl Fluoride: An Alternative Gas to SF₆

Sulfur hexafluoride (SF₆) gas has been used in large-scale electrical equipment, because of its excellent high-voltage dielectric strength. However, SF₆ has been identified as a greenhouse gas, because of its high global warming potential (GWP) and extended lifetime in the atmosphere. Based on theoretical calculations, trifluoromethanesulfonyl fluoride (CF₃SO₂F) is a relatively eco-friendly gas with a lower GWP than that of SF₆, and the electrical performance of CF₃SO₂F is also superior to that of SF₆. A new procedure to synthesize CF₃SO₂F gas is presented for application in high-voltage insulation. An AC breakdown voltage test involved mixing CF₃SO₂F with CO₂ and N₂ to obtain insulation data. The stability of CF₃SO₂F was shown by self-recoverability tests and decomposition product analysis after breakdown, and the results show no harmful or flammable and explosive byproduct that would have a negative climate impact. These results demonstrate that CF₃SO₂F gas has great potential as a new insulating gas with great dielectric strength.