Phosphorescence devices

Due to the large band gap and high triplet energy level of the poly(3, 6-dibenzosilole) 5, the copolymer is an excellent host for the fabrication of blue polymer phosphorescent light-emitting diodes. A high external quantum efficiency (t/el) of 4.8% and a luminance efficiency of 7.2 cd/A at 644 cd/m2 have been achieved for blue phosphorescence devices (emission peak (AEL) at 462 nm, CIE coordinates x = 0.15,y = 0.26). The performances of the devices are much better than those reported for blue phosphorescent devices with poly(A--viny 1 cabarzo 1 e) (PVK) as the host.32... 

Fig. 11.1 The electro-phosphorescent device structure used by Ikai et al. [17], Also shown are the chemical structures of CBP, BCP, TCTA, CF-X and CF-Y. The power efficiency of the organic electrophosphorescent devices is shown in the lower graph.

Phosphorescent Devices with Other Host Polymers... 

Fig. 11.25 Summary of best values of the external quantum efficiency and power conversion efficiency, reported for polymer-based electro-phosphorescent devices over the past 3 years.

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