High-Performance White Emission Polarized Single Crystal and Device
Organic light-emitting devices (OLEDs) offer flexibility, lightweight design, and low manufacturing cost, but their emission is typically unpolarized, limiting applications in optical communication, 3D displays, biological imaging, and quantum computing. Conventional polarized light generation relies on external polarizers, which complicates miniaturization and reduces emission intensity. Intrinsically polarized light-emitting materials are sought, yet achieving white-color intrinsically polarized luminescence remains challenging due to a lack of suitable materials and efficient preparation methods. This study reports a groundbreaking fabrication strategy for white organic polarized emissive semiconductor single crystals (WOPESSCs). Using 2,6-diphenylanthracene (DPA) as the host single crystal, tetracene (Tc) and pentacene (Pen) were co-doped into the crystal bulk at mass ratios of 3% and 0.5%, respectively. Density functional theory calculations confirmed that the molecular sizes of Pen and Tc are slightly smaller than DPA, enabling incorporation into the DPA lattice. Spectral overlap between DPA fluorescence and Tc/Pen absorption indicated efficient energy transfer. The fluorescence emission spectra of DPA, Tc, and Pen span blue, green, and red regions, enabling white light generation. Double-doped single crystals with near-white-light emission were grown, and large-scale fabrication was realized on a 0.9 cm × 0.9 cm silicon wafer. The WOPESSCs exhibited uniform luminescence with a photoluminescence quantum yield (PLQY) of 38.3%. X-ray diffraction confirmed that the bc crystal plane was parallel to the substrate. Polarized fluorescence and electroluminescence spectra were measured, revealing a strong dependence of fluorescence intensity on polarization angle. The degree of polarization (DOP) values were 0.96 at 450 nm, 0.71 at 500 nm, and 0.69 at 610 nm. The WOPESSCs were successfully integrated into polarized organic light-emitting diodes (OLEDs), demonstrating their potential for advanced optoelectronic applications.