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Title: Spatial exciton allocation strategy with reduced energy loss for high-efficiency fluorescent/phosphorescent hybrid white organic light-emitting diodes

Journal Article · · Materials Horizons
DOI:https://doi.org/10.1039/c7mh00131b· OSTI ID:1429117
ORCiD logo [1];  [2];  [2];  [3];  [4];  [5];  [3];  [6]
  1. South China Univ. of Technology (SCUT), Guangzhou (China). Inst. of Polymer Optoelectronic Materials and Devices, State Key Lab. of Luminescent Materials and Devices; Univ. of California, Los Angeles, CA (United States). Henry Samueli School of Engineering and Applied Science and Dept. of Materials Science and Engineering
  2. Heilongjiang Univ., Harbin (China). Ministry of Education and State Key Lab. of Functional Inorganic Material Chemistry
  3. Univ. of California, Los Angeles, CA (United States). Henry Samueli School of Engineering and Applied Science and Dept. of Materials Science and Engineering
  4. King Saud Univ., Riyadh (Saudi Arabia). Dept. of Chemistry
  5. King Saud Univ., Riyadh (Saudi Arabia). Dept. of Chemistry; Alfaisal Univ., Riyadh (Saudi Arabia). College of Science and General Studies and Dept. of Chemistry
  6. South China Univ. of Technology (SCUT), Guangzhou (China). Inst. of Polymer Optoelectronic Materials and Devices, State Key Lab. of Luminescent Materials and Devices; King Saud Univ., Riyadh (Saudi Arabia). Dept. of Chemistry

Due to the poor operational lifetime of blue phosphorescent dopants and blue thermally activated delayed fluorescent (TADF) materials, hybrid white organic light-emitting diodes (WOLEDs) with conventional blue fluorescent emitters are still preferred for commercial applications in general lighting. However, the improvement in the overall efficiency of hybrid WOLEDs has been limited due to energy losses during the energy transfer process and exciton quenching after the spatial separation of the singlet and triplet excitons. Here we demonstrate the development of a Spatial Exciton Allocation Strategy (SEAS) to achieve close to 100% internal quantum efficiency (IQE) in blue-yellow complementary color hybrid WOLEDs. The employed blue fluorophore not only has a resonant triplet level with the yellow phosphor to reduce energy loss during energy transfer processes and triplet–triplet annihilation (TTA), but also has a resonant singlet level with the electron transport layer to extend singlet exciton distribution and enhance both singlet and triplet exciton utilization. Thus, the resulting hybrid WOLEDs exhibited 104 lm W-1 efficacy at 100 cd m-2 and 74 lm W-1 at 1000 cd m-2 with CIE coordinates of (0.42, 0.44) which is warm white and suitable for indoor lighting.

Research Organization:
Univ. of California, Los Angeles, CA (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Grant/Contract Number:
EE0006674
OSTI ID:
1429117
Journal Information:
Materials Horizons, Vol. 4, Issue 4; ISSN 2051-6347
Publisher:
Royal Society of ChemistryCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 44 works
Citation information provided by
Web of Science

References (36)

High-Performance Hybrid White Organic Light-Emitting Devices without Interlayer between Fluorescent and Phosphorescent Emissive Regions journal December 2013
Highly Efficient Blue-Emitting Cyclometalated Platinum(II) Complexes by Judicious Molecular Design journal May 2013
Highly efficient white organic light emitting diodes comprising an interlayer to separate fluorescent and phosphorescent regions journal August 2006
Enhanced efficiency and reduced roll-off in blue and white phosphorescent organic light-emitting diodes with a mixed host structure journal May 2009
Deep Blue Exciplex Organic Light-Emitting Diodes with Enhanced Efficiency; P-type or E-type Triplet Conversion to Singlet Excitons? journal December 2012
On the triplet distribution and its effect on an improved phosphorescent organic light-emitting diode journal August 2012
A hybrid white organic light-emitting diode with stable color and reduced efficiency roll-off by using a bipolar charge carrier switch journal June 2012
Highly Efficient Simplified Single-Emitting-Layer Hybrid WOLEDs with Low Roll-off and Good Color Stability through Enhanced Förster Energy Transfer journal December 2015
Recent Development of Blue Fluorescent OLED Materials and Devices journal September 2005
Triplet Harvesting in Hybrid White Organic Light-Emitting Diodes journal May 2009
Enhancement of electroluminescence efficiency and stability in phosphorescent organic light-emitting diodes with double exciton-blocking layers journal April 2013
Highly efficient hybrid warm white organic light-emitting diodes using a blue thermally activated delayed fluorescence emitter: exploiting the external heavy-atom effect journal January 2015
High-Performance Blue Phosphorescent OLEDs Using Energy Transfer from Exciplex journal January 2014
Deep-Blue Phosphorescence from Perfluoro Carbonyl-Substituted Iridium Complexes journal September 2013
60.1: Invited Paper: Tandem Hybrid White OLED Devices with Improved Light Extraction journal January 2009
Hybrid white organic light-emitting diodes with a double light-emitting layer structure for high color-rendering index journal October 2012
Room temperature triplet state spectroscopy of organic semiconductors journal January 2014
White organic light-emitting diodes with fluorescent tube efficiency journal May 2009
High-Efficiency Blue and White Organic Light-Emitting Devices Incorporating a Blue Iridium Carbene Complex journal September 2010
Exciton diffusion lengths of organic semiconductor thin films measured by spectrally resolved photoluminescence quenching journal March 2009
Management of singlet and triplet excitons for efficient white organic light-emitting devices journal April 2006
Harvesting Excitons Via Two Parallel Channels for Efficient White Organic LEDs with Nearly 100% Internal Quantum Efficiency: Fabrication and Emission-Mechanism Analysis journal January 2009
A Highly Efficient Universal Bipolar Host for Blue, Green, and Red Phosphorescent OLEDs journal June 2010
High-Performance Hybrid White Organic Light-Emitting Diodes with Superior Efficiency/Color Rendering Index/Color Stability and Low Efficiency Roll-Off Based on a Blue Thermally Activated Delayed Fluorescent Emitter journal February 2016
Organic light-emitting diodes employing efficient reverse intersystem crossing for triplet-to-singlet state conversion journal March 2012
Efficient blue organic light-emitting diodes employing thermally activated delayed fluorescence journal March 2014
Cool and warm hybrid white organic light-emitting diode with blue delayed fluorescent emitter both as blue emitter and triplet host journal January 2015
Multifunctional carbazolocarbazoles as hole transporting and emitting host materials in red phosphorescent OLEDs journal January 2013
Confinement of triplet energy on phosphorescent molecules for highly-efficient organic blue-light-emitting devices journal July 2003
Unlocking the full potential of organic light-emitting diodes on flexible plastic journal October 2011
Organic Light-Emitting Devices for Solid-State Lighting journal July 2008
Enhanced exciton diffusion in an organic photovoltaic cell by energy transfer using a phosphorescent sensitizer journal April 2009
Management of charges and excitons for high-performance white organic light-emitting diodes journal January 2010
White Organic Light-Emitting Diodes with Fluorescent Tube Efficiency journal January 2009
Highly Efficient Blue-Emitting Cyclometalated Platinum(II) Complexes by Judicious Molecular Design journal May 2013
Room temperature triplet state spectroscopy of organic semiconductors text January 2013

Cited By (13)

High-Quality White Organic Light-Emitting Diodes Composed of Binary Emitters with Color Rendering Index Exceeding 80 by Utilizing Color Remedy Strategy journal January 2019
Ultrahigh-Efficiency Green PHOLEDs with a Voltage under 3 V and a Power Efficiency of Nearly 110 lm W −1 at Luminance of 10 000 cd m −2 journal September 2017
Blue Thermally Activated Delayed Fluorescence-Emitting Phosphine Oxide Hosts for Ultrasimple and Highly Efficient White Organic Light-Emitting Diodes journal April 2018
High-Efficiency Blue Dual-Emissive Exciplex Boosts Full-Radiative White Electroluminescence journal July 2018
Bis-Tridentate Iridium(III) Phosphors with Very High Photostability and Fabrication of Blue-Emitting OLEDs journal July 2018
Optimized electron-transport material based on m-terphenyl-diphenylphosphine oxide with the harmonious compatibility of high E T and electron mobility for highly efficient OLEDs journal January 2017
New tetrafluorophenylene/carbazole hybrid host materials for phosphorescence organic light-emitting diodes journal January 2018
Design of efficient thermally activated delayed fluorescence blue host for high performance solution-processed hybrid white organic light emitting diodes journal January 2019
Direct white-light emitting room-temperature-phosphorescence thin films with tunable two-color polarized emission through orientational hydrogen-bonding layer-by-layer assembly journal January 2018
To improve the efficiency of thermally activated delayed fluorescence OLEDs by controlling the horizontal orientation through optimizing stereoscopic and linear structures of indolocarbazole isomers journal January 2018
A universal host material with a simple structure for monochrome and white phosphorescent/TADF OLEDs journal January 2019
Design and performance study of high efficiency/low efficiency roll-off/high CRI hybrid WOLEDs based on aggregation-induced emission materials as fluorescent emitters journal January 2019
White polymer light-emitting diodes with ultra-large color shifts for pulse-width-modulation applications journal January 2019