Photoluminescent PMMA polymer films doped with Eu3+-β-diketonate crown ether complex

In this work it is reported the photoluminescence sensitization effect of the bis(dibenzo-18-crown-6)diaquatris(thenoyltrifluoroacetonate)europium(III) compound, [Eu(tta)3(DB18C6)2(H2O)2], doped into a blend of poly(methylmethacrylate) (PMMA) and polyethylene glycol (PEG) in film form. The TGA results indicate that the Eu3+-complex precursor is immobilized in the polymer matrix by the interaction between the Eu3+ complex and the oxygen atoms of the PMMA polymer. The thermal behavior of these luminescent systems is similar to that of the undoped polymer. The emission spectra of the Eu3+-complex in the PMMA/PEG blends recorded at room temperature exhibit the characteristic bands arising from the 5D0 → 7FJ (J = 0–4) intraconfigurational transitions. The emission quantum efficiency of the Eu3+ ion doped films increased significantly, indicating an effective interaction between the Eu3+-complex and the polymer matrix, and both the substitution of water molecules in the first coordination sphere and an efficient luminescence co-sensitization of the Eu3+ luminescent centers.

Photograph of PMMA/PEG blend film doped with 1% [Eu(tta)3(DB18C6)2(H2O)2] complex exhibiting red emission under UV irradiation at 366 nm.Figure optionsDownload as PowerPoint slideHighlights
► Effective interaction between the Eu3+-complex and the polymer matrix are observed.
► The luminescent films are homogeneous and preserve the polymer aspects.
► Emission quantum efficiency for the Eu3+-doped polymer films increased significantly.
► PMMA provides efficient luminescence co-sensitization of the Eu3+ luminescent centers.