Single‐Molecular White‐Light Emitters and Their Potential WOLED Applications

White organic light‐emitting diodes (WOLEDs) are superior to traditional incandescent light bulbs and compact fluorescent lamps in terms of their merits in ensuring pure white‐light emission, low‐energy consumption, large‐area thin‐film fabrication, etc. Unfortunately, WOLEDs based on multilayered or multicomponent (red, green, and blue (RGB)) emissive layers can suffer from some remarkable disadvantages, such as intricate device fabrication and voltage‐dependent emission color, etc. Single molecules, which can emit white light, can be used to replace multiple emitters, leading to a simplified fabrication process, stable and reproducible WOLEDs. Recently, the performance of WOLEDs by using single molecules is catching up with that of the state‐of‐the‐art devices fabricated by multicomponent emitters. Therefore, an increasing attention has been paid on single white‐light‐emitting materials for efficient WOLEDs. In this review, different mechanisms of white‐light emission from a single molecule and the performance of single‐molecule‐based WOLEDs are collected and expounded, hoping to light up the interesting subject on single‐molecule white‐light‐emitting materials, which have great potential as white‐light emitters for illumination and lighting applications in the world. Different types of single organic white‐light‐emitting molecules and their light‐emitting devices are summarized. The blue and complementary emissions are ascribed to the monomers of molecules and their intra‐ or intermolecular interactions, respectively. The devices based on these molecules exhibit high efficiencies and color stabilities, affording a convenient approach to light up the white organic light‐emitting diodes.