Efficient Circularly Polarized Electroluminescence from Achiral Luminescent Materials

Circularly polarized electroluminescence (CP-EL) is generally produced in organic light-emitting diodes (OLEDs) based on special CP luminescent (CPL) materials, while common achiral luminescent materials are rarely considered to be capable of direct producing CP-EL. Herein, near ultraviolet CPL materials with high photoluminescence quantum yields and good CPL dissymmetry factors are developed, which can induce blue to red CPL for various achiral luminescent materials. Strong near ultraviolet CP-EL with the best external quantum efficiencies (eta(ext)s) of 9.0 % and small efficiency roll-offs are achieved by using them as emitters for CP-OLEDs. By adopting them as hosts or sensitizers, commercially available yellow-orange achiral phosphorescence, thermally activated delayed fluorescence (TADF) and multi-resonance (MR) TADF materials can generate intense CP-EL, with high dissymmetry factors and outstanding eta(ext)s (30.8 %), demonstrating a simple and universal avenue towards efficient CP-EL.

Automated summary

Researchers have developed near ultraviolet circularly polarized luminescent materials with high photoluminescence quantum yields and good circular polarization dissymmetry factors, which can induce circularly polarized electroluminescence from blue to red for achiral materials. By using these materials as emitters, they achieve strong near ultraviolet circularly polarized electroluminescence with the best external quantum efficiencies (eta(ext)s) of 9.0% and small efficiency roll-offs in organic light-emitting diodes.