Lanthanide Coordination Polymers as Photoluminescent Materials for Spectral Modulation in Polymer Film

The development of materials capable of converting ultraviolet radiation into spectrally useful visible light is promising for advanced photonic and agricultural applications. In this study, [Ln(OAc)(tta)₂]ₙ coordination polymers (Ln = Eu³⁺, Gd³⁺, and Tb³⁺; tta = 2-thenoyltrifluoroacetate) were synthesized and characterized by FTIR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analysis, and photophysical techniques. The compounds were obtained as needle-shaped crystals in 59–70% yield. Eu³⁺ and Tb³⁺ derivatives exhibited characteristic red and green emissions, respectively, whereas Gd³⁺ served as a reference for investigating ligand-centered excitation and energy-transfer processes. Excitation and emission spectra, quantum yields, and luminescence lifetimes were evaluated to establish structure–property relationships. Incorporation of [Eu(OAc)(tta)₂]ₙ into an EVA film remarkably enhanced the emission quantum yield, indicating reduced non-radiative deactivation. These results highlight lanthanide coordination polymers as promising spectral-conversion materials combining tunable luminescence and polymer-film processability for emerging light-modulating applications in protected agriculture and advanced photonic technologies with clear, notable technological potential.