Electrochemical behaviors of neodymium ions on a solid iron electrode in molten lithium fluoride and reaction kinetics of forming Nd₂Fe₁₇ intermetallic compound

Nd2Fe17 intermetallic compound exhibits excellent magnetic and microwave absorption properties due to its high saturation magnetization. This work investigated the electrochemical behaviors of neodymium ions on a solid iron electrode in molten LiF, focusing on the reaction kinetics of forming Nd2Fe17 intermetallic compound. The results showed that Nd2Fe17 firstly and then Nd5Fe17 intermetallic compounds formed on the iron electrode. The equilibrium electrode potentials for forming the two intermetallic compounds were measured by open circuit chronopotentiometry. The reaction kinetics of forming Nd2Fe17 intermetallic compound was investigated by cyclic voltammetry and chronopotentiometry. The electrode reaction of forming Nd2Fe17 intermetallic compound was an irreversible process that was diffusion-controlled. The diffusion activation energy and heterogeneous charge transfer rate constant were obtained. The research on the reaction kinetics indicated that the charge transfer rate could be improved by increasing overpotential. The Nd2Fe17 intermetallic compound was successfully prepared on a solid iron electrode by potentiostatic electrolysis.