In this work, we investigated the potential for phosphorescent emitters to achieve the BT.2020 color standard in displays, where the CIE coordinates for red and green are (0.709, 0.292) and (0.170, 0.797), respectively. Optical simulations were performed for both green and red top emission organic light emitting devices (OLEDs). For the green emitter, it is possible to reach (0.170, 0.785) using a spectrum with a peak wavelength (λmax) at 526 nm and a full width at half maximum (FWHM) less than 30 nm. For the red emitter, in order to achieve (0.708, 0.292) while maintaining a high current efficiency (CE), it is important to decrease the FWHM instead of red‐shifting the spectrum. Following the guidance of these simulation results, we designed and synthesized novel deep green (DGD) and deep red phosphorescent (DRD‐II) emitters. The photoluminescent (PL) spectrum of DGD shows an FWHM of 30 nm and a λmax of 523 nm. A top‐emission green OLED built using DGD reached a CE of 171 cd/A at an operating voltage of 3.3 V and a lifetime of 95% of initial brightness (LT95) > 1300 h at 10 mA/cm2 with a CIE (x, y) = (0.170, 0.777). This is, to our knowledge, the best device performance ever reported for a green phosphorescent OLED at this CIE y. The PL spectrum of DRD‐II has a λmax of 630 nm with an FWHM of 30 nm. A top‐emission red OLED built with DRD‐II achieved a CE of 59 cd/A, an operating voltage of 3.2 V and an LT95 over 20,000 h at a drive current of 10 mA/cm2 with a CIE (x, y) = (0.708, 0.292). We also studied the angular dependence of the above devices and found they were comparable to devices with commercial emitters for the Digital Cinema Initiative P3 (DCI‐P3) standard that had a wider FWHM. Combining these green and red emitters with a commercial blue OLED at (0.131, 0.046), we are able to cover 97% of the BT.2020 color gamut. The results using DGD and DRD‐II suggest that they have great potential to satisfy BT.2020 in an organic phosphorescent system.

We demonstrate improved charge balance in organic light emitting devices (OLEDs) by optimizing the hole injection layer (HIL) to control the hole density through the device. Two novel p‐dopants (PDs), PD02 with a shallow lowest unoccupied molecular orbital (LUMO) at ‐4.63 eV (reported in our previous work) and PD03 with a relatively deep LUMO of ‐4.91 eV were used. A two‐layer HIL consisting of HTM:PD02 and HTM:PD03 introduces new design flexibility to improve charge balance in the light emission layer. Using 16% by mass of PD02 and 3% by mass of PD03, we achieve, (1) a bottom emission deep red device with an external quantum efficiency (EQE) of over 30% at a CIE of (0.701, 0.299), an operating voltage of 3.2 V and LT95~13, 000 h at 10 mA/cm2. In particular, the efficiency roll‐off of this device is greatly reduced, which is highly desirable in the display industry. (2) a top emission deep red device with a current efficiency (CE) of 75 cd/A at a CIE of (0.707, 0.293), an operating voltage of 3.6 V and LT95 over 15, 000 h at 10 mA/cm2. An additional benefit from this novel dual p‐doped HIL approach is its much lower lateral conductivity compared to the standard single HIL device structure, resulting in reduced lateral crosstalk between RGB pixels.