Highly Efficient Red and White Organic Light-Emitting Diodes with External Quantum Efficiency beyond 20% by Employing Pyridylimidazole-Based Metallophosphors

• DOI: 10.1021/acsami.7b10300
• Publication Date: 2017-10-10T12:55:12Z
• Authors: Yanqin Miao; Peng Tao; Kexiang Wang; Hongxin Li; Bo Zhao; Long Gao; Hua Wang; Bingshe Xu; Qiang Zhao
• Keywords: Quantum Efficiency

Two highly efficient red neutral iridium(III) complexes, Ir1 and Ir2, were rationally designed synthesized by selecting two pyridylimidazole derivatives as the ancillary ligands. Both Ir2 show nearly same photoluminescence emission with maximum peak at 595 nm (shoulder band about 638 nm) achieve high solution quantum yields of up to 0.47 for 0.57 Ir2. Employing emitters, fabricated organic light-emitting diodes (OLEDs) outstanding performance external efficiency (EQE), current (CE), power (PE) 20.98%, 33.04 cd/A, 33.08 lm/W Ir1-based device 22.15%, 36.89 35.85 Ir2-based device, respectively. Furthermore, using emitter, a trichromatic hybrid white OLED, showing good warm low correlated color temperature <2200 K under voltage 4–6 V, was successfully. The also realizes excellent efficiencies EQE, CE, PE reaching 22.74%, 44.77 46.89 lm/W, Such electroluminescence OLEDs indicates that phosphors have great potential future OLED displays lightings applications.