Theoretical assessment of discharge effects on the decomposition tendency of C6F12O over metallic surfaces

Abstract

Abstract C6F12O is proposed to be one potential eco‐friendly insulation gas to replace SF6. However, the assessment of its decomposition properties and the compatibility with metal electrodes in discharge faults is still challenging, which greatly hinders the development of its insulation and arc‐extinction applications. Herein, a theoretical method is proposed to reasonably address the discharge effects on C6F12O decomposition over typical Cu and Al electrodes at atomic scale. The results show that both the external electric field and the excess electrons could affect the activation of C6F12O by changing the electron acceptance of C6F12O and the orbital hybridisation during the surface bonding. On metal surfaces, the C‐F single bond in adsorbed C6F12O is the weakest position to decompose, and its cleavage could be promoted by the discharge effects. After the C‐F breaking, the C‐C cleavage remains unfavourable on Cu (111), but it is significantly promoted on Al (111), indicating a higher corrosion risk on the Al surface via continuous C6F12O decompositions. The proposed method as a valid supplement to the experiment reveals the discharge effects and the decomposition tendency of C6F12O on metal electrodes in discharge faults, which broadens the means for insulation gas evaluation.