Effect of doped trinuclear europium complexes on the photoluminescence of biodegradable Polybutylene succinate films

Abstract

The combination of rare earth complexes and polymer matrix can be made into a series of light-transfer films with luminescence effects, which have wide applications in various fields. In this study, two trinuclear Eu-complex precursors Eu3(TTA)9trisphen and Eu3(DBM)9trisphen were doped into polybutylene succinate (PBS) with doping percentage at 1, 3, 5 and 7 wt%, and the resulting Eu3+/PBS luminescence films were also investigated by FT-IR, TGA, DSC, and photoluminescence spectroscopy. The characteristic peak at 1614 cm−1 in FT-IR spectra demonstrated the effective binding of the polymer matrix and Eu-complex. On the basis of TGA data, it has been found that the initial decomposition temperature of the composite system increased with increase of Eu-complex doped concentration, indicating that Eu/PBS luminescence films have good thermal stability. Most importantly, the emission spectra showed that the luminescence intensity of the Eu-complexes could be enhanced by the PBS matrix, especially the quantum efficiency (η) of the luminescence film reached to as high as 30.72% by doping with 7 wt% Eu3(TTA)9trisphen. These facts revealed that the polymer matrix acted as an efficient co-sensitizer for Eu3+ ions luminescent center. As we known, this is first example that doping trinuclear Eu-complexes into the environmentally-friendly polymer matrix to fabricate the luminescent Eu/polymer films.