Modulating the photoluminescence of europium-based emitting polymers: Influence of the matrix on the photophysical properties

A series of luminescent materials have been prepared by the ternary europium complex Eu(tta)3(phen) (tta = 2-thenoyltrifluoroacetonato, phen = 1,10-phenanotroline) embedded into different polymer matrixes (polystyrene, poly(vinyl difluoride), poly(acrylonitryle) and poly(methyl methacrylate)) in order to investigate the effect of the polymer on the luminescent properties of the hybrid materials. Fourier transform infrared spectra (FTIR), UV/vis spectra, scanning electron microstructure (SEM) and luminescent properties of the europium complex and the hybrid materials are described in detail. In all cases, interaction between the polymer and the europium complex was observed from the above techniques. This interaction was strong enough to lead to a variation in the photoluminescent properties of the hybrid films: while poly(vinyl difluoride) doped polymers showed a reduce quantum yield (ϕ = 24%), a dramatic/significant enhanced in this parameter (ϕ up to 73%) was observed for the other materials in comparison with the ϕ value of the precursor complex (30.5%). This result may support the conclusion that while some polymers could interact with the complex, act as antennae and transfer energy to the central Eu(III) ion, other quench the luminescence of the complex. Based on this high ϕ, these films could be applied in top optical applications such as light-emitting diodes and/or active polymer optical fibers.