Ionic Liquids for Lanthanide and Actinide Chemistry

Abstract

Ionic liquid chemistry has developed into a tremendously popular field of chemistry in the last decade. It has been realized that ionic liquids show features that cannot be realized in conventional molecular solvents. The widely tuneable class of ionic liquids has become important for lanthanide and actinide coordination chemistry, f‐element spectroscopy, f‐element electrochemistry and electrodeposition, organic synthesis and catalysis as well as inorganic nanomaterial synthesis. For example, ionic liquids offer the possibility to synthesize and crystallize quite uncommon lanthanide compounds. Ionic liquids can also be designed in such a way that they become excellent media to study the optical properties of lanthanide compounds. And even ionic liquids based on f‐elements can be made. Hydrophobic ionic liquids may replace organic solvents in liquid/liquid f‐element extraction processes, not only as a safer extraction phase but also as a smart extractant. Their wide electrochemical window and large ion conductivity make ionic liquids interesting solvents to study the electrodeposition of the very electropositive lanthanide elements. For f‐element‐catalyzed reactions, higher reaction rates, enhanced selectivity, better immobilization of the catalyst and an easy product recovery have often been observed in certain ionic liquids.