Imidazolium cations, such as those commonly used in preparing ionic liquids
(ILs) can easily be derivatized to include task-specific functionality, su
ch as metal ligating groups that when used as part of the solvent or doped
into less expensive ILs, dramatically enhance the partitioning of targeted
metal ions into the IL phase from water; the strategy of preparing task-spe
cific ILs is applicable to a wide range of designer solvent needs.