Highly stable Eu-coordination polymer exhibiting the highest quantum yield

Lanthanide luminescent materials with high quantum yield and thermal stability are of key importance for their practical application. Here we report crystal structures and luminescent properties of [Eu(pfbz) 2 (phen)Cl] ( 1 ) and [Tb(pfbz) 2 (phen)Cl] ( 2 ) (pfbz = Pentafluorobenzoate). Single-crystal analysis reveals that both 1 and 2 crystallize in a polar space group of Cmc 2 1 . Investigation on their luminescent properties indicates that the solid-state quantum yields of 1 and 2 are 97.7% and 90.7%, respectively, while their efficiency of the sensitization process is as high as 100%, revealing that polar structures are more favorable to obtain high quantum yields. Thermogravimetric analysis reveals that both 1 and 2 can be stable up to 240 °C. More importantly, temperature-dependent luminescent spectra of 1 indicate its luminescent intensity at 612 nm only decreased by 5% from room temperature to 373 K, whereas at 373 K, its luminescent intensity remains almost constant for 36 h. Considering that 1 represents the highest quantum yield among known Eu-coordination polymers and its performance as the LED material is better than that of commercially widely used luminescent materials of (Sr,Ca)AlSiN 3 :Eu (630 nm) and (Sr,Ca)AlSiN 3 :Eu (640 nm), the present work provides an excellent substitute for commercial LED materials.