Luminescent Materials of Europium(III) Coordinated by a Terpyridine-Functionalized Poly(Ionic Liquid)

A new poly(ionic liquid) (Terpy-PIL) carrying a terpyridine group in each repeating unit of the polymer architecture was readily prepared by polymerization of the monomer (Terpy-IL), which was initiated by azobis(isobutyronitrile) (AIBN). The obtained poly(ionic liquid) can coordinate and sensitize europium(III) ions through numerous chelating terpyridine moieties, which are linked to the polymer chains. A red-emitting luminescent material was obtained by the complexation of europium(III) salts with Terpy-PIL, and the luminescence is due to an energy transfer from the terpyridine moieties to Eu3+ ions. The luminescence performance of the luminescent material based on Terpy-PIL, for example the D-5(0) quantum efficiency and the decay time, is much higher than that of the luminescent material prepared from the monomer Terpy-IL, which can be ascribed to the confinement of the europium(III)-terpyridine complexes to the polymer architecture.