Blue Thermally Activated Delayed Fluorescence‐Emitting Phosphine Oxide Hosts for Ultrasimple and Highly Efficient White Organic Light‐Emitting Diodes. Issue 12 (10th April 2018)

• Record Type: Journal Article
• Authors: Liang, Qianqian; Han, Chunmiao; Duan, Chunbo; Xu, Hui
• Is Part Of: Advanced optical materials. Volume 6:Issue 12(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-04-10
• Subjects: device simplification -- host materials -- phosphine oxide -- thermally activated delayed fluorescence -- white emission; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.201800020
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: Among a series of carbazole–diphenylphosphine oxide hybrids x 2ArPO, blue thermally activated delayed fluorescence (TADF)‐emitting host m 2tBCzPO with optimal electron‐withdrawing and steric effects is successfully constructed to demonstrate the superiority of blue TADF‐emitting host in adaptable exciton allocation for white light‐emitting diodes (WOLEDs), which realizes the negligible singlet–triplet splitting (Δ E ST ) of 0.02 eV, the photoluminescence quantum yield beyond 75% and the top‐rank external quantum efficiency (EQE) with the maxima of 13.8% and 22.2% from its blue and yellow devices. Its high‐efficiency blue TADF emission and excellent host characteristics are perfectly harmonized in its ultrasimple four‐layer WOLED with monodoping single‐emissive layer to support the state‐of‐the‐art performance, including EQE up to 21.3%, roll‐off within 10% at 1000 cd m −2, and excellent spectral stability. Abstract : Blue thermally activated delayed fluorescence (TADF)‐emitting host m 2tBCzPO with optimized electron‐withdrawing and steric effects is constructed to integrate the high‐efficiency blue TADF emission and the excellent host characteristics. These two functions are perfectly harmonized in its ultrasimple four‐layer white light‐emitting diodes with monodoping single emissive layer to support the state‐of‐the‐art performance.