Rational Multidimensional Shielded Multiple Resonance Emitter Suppresses Concentration Quenching and Spectral Broadening for Solution-Processed Organic Light-Emitting Diodes

作者：Xie, Feng-Ming; Li, Hao-Ze; Zhang, Kai; Wang, Han-Yang; Li, Yan-Qing^*; Tang, Jian-Xin^*

来源：ACS applied materials & interfaces, 2023.

DOI：10.1021/acsami.3c07852

• multiple resonance
• solution-processed
• fullwidth at half-maximum
• aggregation-caused quenching
• organic light-emitting diodes

Thermally activated delayed fluorescence (TADF) emittersbasedon multiple resonance (MR) effects are promising for high-definitionorganic light-emitting diodes (OLEDs) with narrowband emission andhigh efficiency. However, they still face the challenges of aggregation-causedquenching (ACQ) and spectral broadening. Solution-processable MR-TADFemitters with an external quantum efficiency (EQE) of >20% anda fullwidth at half-maximum (fwhm) of <30 nm have rarely been reported.To construct ACQ-resistant emitters without sacrificing color purity,the aggregation-induced MR-TADF material 6TBN with arigid B,N-containing polycyclic aromatic hydrocarbon core and fourcarbazole substituents as well as 12 tert-butyl groupson the periphery is designed. The multidimensional shielded effectlargely limits the ACQ, intermolecular interactions, and spectralbroadening. Consequently, solution-processed OLEDs based on 6TBN exhibit a maximum EQE of 23.0% and high color puritywith a fwhm of 25 nm. Furthermore, the nondoped device achieves ahigh efficiency (12.3%) and merely a slight widening of the fwhm to27 nm. This work provides a feasible strategy to achieve MR-TADF materialswith resistance to concentration quenching and high color purity.

• 单位
  苏州大学