Electroanalytical Chemistry of Lanthanides/Actinides and the Feasibility of Direct Electrodeposition in Ligand Containing Ionic Liquids: A Comprehensive Review

Abstract

Electrochemistry is an important research domain to realize the electrochemical transitions of a target species in its feed solution. The area has wide applications in the non-aqueous as well as aqueous reprocessing of spent nuclear fuels (SNFs). In the present review, all the literature reports dealing with the electrochemical behavior of lanthanides and actinides in ionic liquid (IL) solvents containing strongly coordinating extractants and the feasibility of their direct electrodeposition intended towards a novel wing of the aqueous reprocessing have been gathered and discussed in a comprehensive manner. The variation in the electrochemical results in IL phase based on the ligand structure and the functional moiety present in it has been highlighted by correlating the complexing ability of these extractants with metal ions. Decisive parameters such as diffusion coefficient (D), charger transfer coefficient (α), charge transfer rate constant (k s), activation energy (E a), etc, have been compared with each other to draw out the consequence of a particular ligand/IL system. The novelty of electrochemistry in Neutral Ligand Ionic Liquids (NLILs) has been showcased in detail. The practicality of direct electrodeposition from the extracted IL phase has also been covered in the review to draw an innovative pathway of metal ion recovery.