Efficient and Stable White Organic Light‐Emitting Diodes Employing a Single Emitter

Abstract

Using a single tetradentate platinum emitter dubbed Pt7O7, efficient and stable white organic light-emitting diodes are developed. The excimer-based white devices achieve an external quantum efficiency (EQE) of 24.5%, coordinates of (0.37, 0.42) based on the Commission internationale de l'éclairage (CIE) system, and a color rendering index (CRI) of 70. Moreover, devices of Pt7O7 in a stable structure demonstrate operational lifetimes (50% initial luminance) of 36 h at an elevated driving current of 20 mA cm2, which corresponds to over 10,000 h at 100 cd m2.

Characterization, modeling, and analysis of organic light-emitting diodes with different structures

“…Content may change prior to final publication. (16) where L ave is the average luminance, L min is the minimum luminance, U is the luminance uniformity.…”

Organometallic Versus Organic Molecules for Energy Conversion in Organic Light-Emitting Diodes and Solar Cells

“…Pt-1 bearing tetradentate O^N^C^N ligands displays high emission quantum efficiency of 90 % and is an excellent green phosphorescent dopant for OLEDs with excellent efficiency of 66.7 cd/A and low efficiency roll-off [43]. The blue-emitting device employing Pt-2 demonstrated a peak η ext of 26.3 % and CIE coordinates of (0.12, 0.24) [44]. The excimer formation from Pt-2 resulted in white emission from OLEDs which exhibited a peak η ext of 25.7 % with a CRI of 70.…”

Recent advances in white organic light-emitting diodes employing a single-emissive material

“…10. 36 This cyclometalated Pt complex showed a narrow monomer peak at 472 nm and an excimer peak at 592 nm and is capable of achieving a warm white with color coordinates of (0.37, 0.43) and a CRI of 70. Remarkably, this emitter exhibited efficient emission across all the tested concentrations, achieving a peak EQE of 26.3% for low-dopant concentrations of 2% and 24.1% for dopant concentrations as high as 18%.…”

“…34 Through careful theoretical work on phosphorescent excimers, the design of new device structures, and the development of new emissive materials, a greater understanding of the factors controlling the excimer emission has been achieved and a white device exceeding 20% has now been demonstrated. 35,36 The device performance of selected reports that demonstrate this progress is given in Table 2. In this article, we will review the recent progress in the development of single-doped WOLEDs employing Ptbased excimer emitters.…”