Highly Efficient Inverted Circularly Polarized Organic Light-Emitting Diodes
- 5 August 2020
- journal article
- research article
- Published by American Chemical Society (ACS) in ACS Applied Materials & Interfaces
- Vol. 12 (35), 39471-39478
- https://doi.org/10.1021/acsami.0c09139
Abstract
Circularly polarized (CP) electroluminescence has been demonstrated as a strategy to improve the performance of organic light emitting diode (OLED) displays. CP emission can be generated from both small molecule and polymer OLEDs (SM-OLEDs and PLEDs), but to date, these devices suffer from low dissymmetry factors (g-factor <0.1), poor device performance, or a combination of the two. Here, we demonstrate the first CP-PLED employing an inverted device architecture. Through this approach, we demonstrate a highly efficient CP-PLED, with a current efficiency (CE) of 16.4 cd/A, a power efficiency (PE) of 16.6 lm/W, a maximum luminance of over 28,500 cd/m2, and a high EL dissymmetry (gEL) of 0.57. We find that the handedness of the emitted light is sensitive to the PLED device architecture: the sign of CP-EL from an identically prepared active layer reverses between inverted and conventional devices. The inverted structure affords the first demonstration of CP-PLEDs exhibiting both high efficiency and high dissymmetry – the two figures of merit which, until now, have been difficult to achieve at the same time. We also highlight device architecture and associated internal electric field to be a previously unexplored means to control the handedness of CP emission. Our findings significantly broaden the versatility of CP emissive devices and should enable their further application in a variety of other CP-dependent technologies.Keywords
Funding Information
- Engineering and Physical Sciences Research Council (EP/L016702/1, EP/P000525/1, EP/R00188X/1)
This publication has 51 references indexed in Scilit:
- Recent advances in circularly polarized electroluminescence based on organic light-emitting diodesChemical Society Reviews, 2020
- Recent Progress on Circularly Polarized Luminescent Materials for Organic Optoelectronic DevicesAdvanced Optical Materials, 2018
- Highly Efficient Circularly Polarized Electroluminescence from Aggregation‐Induced Emission Luminogens with Amplified Chirality and Delayed FluorescenceAdvanced Functional Materials, 2018
- Circularly Polarized Phosphorescent Electroluminescence with a High Dissymmetry Factor from PHOLEDs Based on a PlatinaheliceneJournal of the American Chemical Society, 2016
- Purely organic electroluminescent material realizing 100% conversion from electricity to lightNature Communications, 2015
- Highly Circularly Polarized Electroluminescence from a Chiral Europium ComplexAdvanced Materials, 2015
- Induction of Circularly Polarized Electroluminescence from an Achiral Light‐Emitting Polymer via a Chiral Small‐Molecule DopantAdvanced Materials, 2013
- Device efficiency of organic light‐emitting diodes: Progress by improved light outcouplingPhysica Status Solidi (a), 2012
- Nearly 100% internal phosphorescence efficiency in an organic light-emitting deviceJournal of Applied Physics, 2001
- Analytical applications of circular dichroismJournal of Pharmaceutical and Biomedical Analysis, 1989