In this work,the degradation behavior of 1-butyl-3-methylimidazole hexafluorophosphate (BMIMPF6) under different temperature and pressure conditions and the influence of SiO2 on its degradation behavior were researched.The BMIMPF6 and BMIMPF6/SiO2 were subjected to various treatments,including high pressure at room temperature,high temperature at low pressure,and high temperature at high pressure by using a piston cylinder and a double-sided top press.The structure and composition of the treatment products were analyzed by Fourier transform infrared spectroscopy (FT-IR),Raman spectroscopy (Raman) and nuclear magnetic resonance (NMR) analysis.The results showed that the ionic liquid BMIMPF6 underwent partial thermal degradation at 120℃,0.1MPa and 1000MPa.However,the pressure did not significantly change the thermal degradation behavior of the ionic liquid.Under the same temperature and pressure conditions,the thermal degradation reaction of the ionic liquid BMIMPF6 was deeper when silica was involved.The thermal degradation mechanism of ionic liquid BMIMPF6 was analyzed from the perspective of chemical reaction paths,and the possible thermal degradation reaction process of liquid BMIMPF6 with the participation of silica was given.
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基金资助
国家自然科学基金(21503194);河南省科技攻关项目(242102230109);河南省自然科学基金(252300420354)
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