Green synthesis of luminescent soft materials derived from task-specific ionic liquid for solubilizing lanthanide oxides and organic ligand

Herein we report a facile method to prepare highly luminescent soft materials based on task-specific ionic liquids which can solubilize lanthanide oxides and the organic ligand. The luminescent soft materials are obtained by directly dissolved lanthanide oxides and organic ligand (2-Thenoyltrifluoroacetone (TTA), 1, 10-phenanthroline (Phen)) into carboxyl-functionalized ionic liquid aided with an appropriate amount of water. FT-IR, TGA and luminescence spectroscopy were employed to characterize the lanthanide-containing ionic liquids. Up to 25 mol % lanthanide ions (i.e., the molar ratio of IL/Ln³⁺ = 3:1) can be incorporated into the task-specific ionic liquids. Optical properties of the soft materials such as colour, luminescence can be adapted by simply changing the type of lanthanide ions and/or adding to organic ligand.