Intrinsically white organic polarized emissive semiconductors

Abstract

Polarized emissive media are crucial for various applications in display, lighting and optical communication. An attractive research direction is to develop intrinsically white organic polarized emissive semiconductors as ideal candidates for miniaturized polarized light-emitting devices; however, it has been a considerable challenge to achieve polarized white-light emission due to the lack of suitable materials and effective preparation methods. Here we overcome this bottleneck by realizing white organic polarized emissive semiconductor single crystals (WOPESSCs). We employ a bimolecular doping method based on using highly polarized, blue-emitting 2,6-diphenylanthracene as the host single crystal, and controlling energy and polarization transfer with green- and red-emitting guests. The fabricated WOPESSCs achieve a photoluminescence quantum yield of 38.3% and a mobility of 4.9 cm2 V–1 s–1. The emitted light exhibits a degree of polarization as high as 0.96 with Commission Internationale de l’Eclairage coordinates of (0.3258, 0.3396). We also demonstrate the tunable emission properties of WOPESSCs from blue–white to yellow–white light by adjusting polarization angles, and three-primary-colour optical imaging with a wide colour gamut that covers 112% of the National Television System Committee standard. Furthermore, we fabricate highly polarized microscale WOPESSCs light-emitting diodes and light-emitting transistors, achieving high-quality white-light emission and wide-range colour tunability enabled by gate voltage-driven energy transfer processes. We believe these findings pave the way for manufacturing white and multicolour polarized emissive semiconductors and microscale light-emitting devices, promising diverse applications across various fields. A bimolecular doping strategy enables the realisation of white organic polarized emissive semiconductor single crystals, emitting white light with a maximum degree of polarization as high as 0.96. Organic polarized light-emitting diodes and light-emitting transistors with tuneable emission wavelength are also demonstrated.