Electrochemical Behavior of Graphite Anode in LiF-NaF-KF Eutectic with YF3. (20th January 2017)

• Record Type: Journal Article
• Authors: Tian, Lifang; Huang, Wei; Jiang, Feng; Zheng, Haiyang; Zhu, Tiejian; She, Changfeng; Wang, Xianbin; Long, Dewu; Gong, Yu; Wu, Guozhong; Li, Qingnuan
• Is Part Of: Electrochimica acta. Volume 225(2017)
• Page Start: 392
• Page End: 398
• Publication Date: 2017-01-20
• Subjects: FLiNaK -- graphite anode -- electrolysis -- current density -- anode potential; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2016.12.165
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: The electrode reactions and electrolysis process of graphite anode were investigated in LiF-NaF-KF (FLiNaK, 46.5-11.5-42.0 mol%) eutectic with YF3 at 823 K. Two different types of reactions were observed on graphite anode. The graphite was oxidized to carbon mono- and dioxide in a potential range of 0–2 V ( vs. Ni 2+ /Ni, similarly hereinafter), and carbon fluorides were generated when the potential fell into 6–8 V. In addition, some fluoride products could be reduced at about −0.22 V during reverse cyclic voltammetry scan, which has never been reported. Anode potential fluctuation was found between 6 and 8 V during galvanostatic electrolysis due to the formation of gaseous products as well as change of anode surface area and current density. Both Raman and X-ray photoelectron spectroscopy were employed to probe the chemical states of fluorination/oxidation products on graphite anode after electrolysis. The formation of fluorocarbon species is responsible for the disorder on graphite surface.