Praseodymium-Containing Polyfluorene: Synthesis, Photoluminescence, and Electroluminescence

A polyfluorene containing praseodymium complexes was synthesized with fluorene, phenanthroline, and praseodymium triisopropoxide units by way of the conventional coordination reaction and palladium-catalyzed Suzuki coupling reaction. The composition and structure of the polymers were identified by 1 H NMR (nuclear magnetic resonance) spectra. The material is easy to dissolve in most common organic solvents and has high thermal stability, which is beneficial to the device preparation process. Optical characterizations including ultraviolet and visible (UV-vis) absorption spectra, photoluminescence, and electroluminescence of the target polymer were recorded and analyzed to investigate the effects of Pr triisopropoxide. The optoelectronic devices obtained were measured with the configuration ITO/PEDOT:PSS/polymer/TPBi/LiF/Al based on the resulting polymer as an emissive layer. The results show that the praseodymium triisopropoxide complexes in the polymer structure tuned the emission color and improved the performance of the optoelectronic device. Therefore, this technique can provide an inexpensive and straightforward method for the synthesis of lanthanide-complexed copolymer applied in the field of organic optoelectronic materials. Graphical Abstract A praseodymium (Pr)-bonded polymer with fluorene, phenanthroline, and Pr triisopropoxide in the main chain was synthesized via coordination reaction and Suzuki reaction. The photoluminescence and electroluminescence properties of the polymer were studied to explore the effects of Pr triisopropoxide. The introduction of Pr triisopropoxide into the polymer tuned the emission color and improved the performance of the optoelectronic device.