Electrochemical investigation of the anode processes in LiF–NdF3 melt with low oxygen content
来源期刊：International Journal of Minerals Metallurgy and Materials2021年第3期
论文作者：Chen-ming Fan Shi-zhe Liu Jing-jiu Gu Shi-you Guan Jin-hua Zhao Bing Li
摘 要：The oxidation of oxygen ions and the generation of an anode effect at a low oxygen content of 150 mg/kg were discussed in this paper. Cyclic voltammetry and square-wave voltammetry tests were conducted to explore the anodic processes of LiF–NdF3 melt after a lengthy period of pre-electrolysis purification at 1000°C（during which the oxygen content reduced from 413 to 150 mg/kg）. The oxidation process of oxygen ions was found to have two stages: oxidation product adsorption and CO/CO2 gas evolution. The adsorption stage was controlled by diffusion, whereas the gas evolution was controlled by the electrochemical reaction. In comparison with oxygen content of 413 mg/kg, the decrease in the amplitude of the current at low oxygen content of 150 mg/kg was much gentler during the forward scanning process when the anode effect occurred. Fluorine-ion oxidation peaks that occurred at about 4.2 V vs. Li/Li+ could be clearly observed in the reverse scanning processes, in which fluorine ions were oxidized and perfluorocarbons were produced, which resulted in an anode effect.
Chen-ming Fan1，Shi-zhe Liu1，Jing-jiu Gu1，Shi-you Guan2，Jin-hua Zhao3，Bing Li1
1. School of Mechanical and Power Engineering, East China University of Science and Technology2. Institute for Sustainable Energy, College of Sciences, Shanghai University3. Collaborative Innovation Center of Clean Energy, Longyan University
摘 要：The oxidation of oxygen ions and the generation of an anode effect at a low oxygen content of 150 mg/kg were discussed in this paper. Cyclic voltammetry and square-wave voltammetry tests were conducted to explore the anodic processes of LiF–NdF3 melt after a lengthy period of pre-electrolysis purification at 1000°C（during which the oxygen content reduced from 413 to 150 mg/kg）. The oxidation process of oxygen ions was found to have two stages: oxidation product adsorption and CO/CO2 gas evolution. The adsorption stage was controlled by diffusion, whereas the gas evolution was controlled by the electrochemical reaction. In comparison with oxygen content of 413 mg/kg, the decrease in the amplitude of the current at low oxygen content of 150 mg/kg was much gentler during the forward scanning process when the anode effect occurred. Fluorine-ion oxidation peaks that occurred at about 4.2 V vs. Li/Li+ could be clearly observed in the reverse scanning processes, in which fluorine ions were oxidized and perfluorocarbons were produced, which resulted in an anode effect.
关键词：
