Effect of O 2 on the Thermal Stability and Decomposition Process of C 5 F 10 O.

As a promising environmentally friendly insulating medium, C5F10O needs to be mixed with buffer gases such as technical air to avoid liquefaction. Notably, such a high proportion of oxygen can promote the decomposition of C5F10O and may even eradicate its stability under over-thermal fault. At present, there is still a lack of experimental research investigating the influence of oxygen on the thermal stability of C5F10O, and the mechanism is still unclear. To this end, experiments are carried out on the thermal decomposition properties of C5F10O while mixed with different proportions of O2. And to reveal the mechanism, the dissociation of C5F10O and the reaction of O2 with CF3CO $\cdot $ radical are studied theoretically based on the density functional theory (DFT) and transition state theory (TST). The results signify that oxygen of 4% and above ravages the thermal stability of C5F10O medium, causing it to decompose in a large amount at high temperature, which generates stable products such as CO2, C3F6, C3F8, and C2F6. The mechanism is that O2 is extremely easy to combine with CF3CO $\cdot $ radical to form a complex, which further decomposes, leading to the continuous development of the decomposition of C5F10O. The study revealed the important mechanism of O2 during the decomposition process of C5F10O, providing experimental and theoretical support for the use of C5F10O mixed gas. [ABSTRACT FROM AUTHOR]