Sensitization of Ln III (Ln = Eu, Tb, Tm) Ion Luminescence by Functionalized Polycarbonate‐Based Materials and White Light Generation

We prepared pyridine‐2,6‐bis(ethyl)ester [BEP] and pyridine‐2,6‐bis(diethylamide) [BDP] polymers with polycarbonate backbones by ring‐opening polymerization of the pyridine‐bis(ethyl)ester and pyridine‐bis(diethylamide) units appended to a cyclic carbonate via a glycol chain. The polymers were characterized by FTIR, NMR, UV/Vis absorption and fluorescence spectroscopy, as well as SEC, powder XRD, DSC, and TGA. The measured glass transition temperature ( T g ) of the BEP polymer was shifted from –32 °C to –7 and –8 °C after coordination of the Eu III and Tb III ions, respectively. Similarly, the T g of the BDP polymer was shifted from –13 °C to –9 and –10 °C after coordination of Eu III and Tb III ions, respectively. Both polymers sensitized Ln III ‐centered emission; the BEP polymer was the most efficient at sensitizing Ln III ‐centered luminescence with an emission efficiency of 30 and 31 % for the Eu III and Tb III systems, respectively, compared to the 2 % determined for both the Eu III and Tb III BDP systems. Blue emission was observed when Tm III was used, and a system with the composition BEP 1 Eu 1.8 Tb 28 led to a material with CIE coordinates (0.31, 0.33), typical of white light.