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Multi-Colored Light-Emitting Electrochemical Cells Based on Thermal Activated Delayed Fluorescence Host.

ABSTRACT: Light-emitting electrochemical cells (LECs) with the thermally activated delayed fluorescence(TADF) host and phosphorescent guests were fabricated using solution process. It is demonstrated for the first time that TADF, a well-known phenomenon that helps to increase electroluminescence efficiency by harvesting excitons from triplet states, is used as a host in LECs. Devices with green, yellow, red and warm white emissions were fabricated, with the best devices showing more than 7000?cd/m² stable emission and a peak efficiency over 7?cd/A. Under high voltage stress, a burst of extremely high luminance of over 30,000?cd/m² was observed. All these LEC devices are extremely simple with only one active layer. Thus, our results could pave way to produce low- cost light source with high luminance, using TADF molecules.

SUBMITTER: Liu J

PROVIDER: S-EPMC5431554 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Multi-Colored Light-Emitting Electrochemical Cells Based on Thermal Activated Delayed Fluorescence Host.

Liu Jiang J Oliva Jorge J Tong Kwing K Zhao Fangchao F Chen Dustin D Pei Qibing Q

Scientific reports 20170508 1

Light-emitting electrochemical cells (LECs) with the thermally activated delayed fluorescence(TADF) host and phosphorescent guests were fabricated using solution process. It is demonstrated for the first time that TADF, a well-known phenomenon that helps to increase electroluminescence efficiency by harvesting excitons from triplet states, is used as a host in LECs. Devices with green, yellow, red and warm white emissions were fabricated, with the best devices showing more than 7000 cd/m<sup>2</ ...[more]

PMID: 28484284

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