Figure 4: Device stability of yellow OLEDs.
From: High-efficiency organic light-emitting diodes with fluorescent emitters
For operational lifetime measurement of the double-dopant system, an OLED with a device structure of ITO/α-NPD (35 nm)/1 wt%-TBRb:25 wt%-PXZ-TRZ:mCBP (30 nm)/T2T (10 nm)/Alq3 (55 nm)/LiF (0.8 nm)/Al (100 nm) (device A) was used. To confirm the effect of the assistant dopant, OLEDs with an EML of either 1 wt%-TBRb:mCBP (device B) or 25 wt%-PXZ-TRZ:mCBP (device C) were also measured at a constant current density of 10 mA cm−2. Initial luminances (L0) are 3,225, 677 and 2,791 cd m−2 for devices A, B and C, respectively. Inset: voltage rise curves for devices A, B and C (coloured accordingly).
