Narrowing the Electroluminescence Spectra of Multiresonance Emitters for High-Performance Blue OLEDs by a Peripheral Decoration Strategy

• DOI: 10.1021/acsami.1c18704
• Publication Date: 2021-12-01T22:13:02Z
• Authors: Yuntao Qiu; Han Xia; Jingsheng Miao; Zhongyan Huang; Nengquan Li; Xiaosong Cao; Jianmei Han; Changjiang Zhou; Cheng Zhong; Chuluo Yang
• Keywords: Quantum yield; Quantum Efficiency; Intersystem crossing

Developing organic thermally activated delayed fluorescence (TADF) emitters with high efficiency and narrowband emissions is crucial challenging for high-quality light-emitting diodes (OLEDs). Here, three multiresonance TADF DPACzBN1, DPACzBN2, DPACzBN3 are designed via a peripheral decoration strategy synthesized through lithium intermediate cascade borylation reaction (15% yield DPACzBN1) or more efficient lithium-free direct (45% DPACzBN2 75% DPACzBN3). All the exhibit similar blue emission small full-width at half maximum (fwhm) values as low 20 nm in toluene solutions. The introduction of diphenylamino moiety into parent molecule DPACzBN1 can not only maintain photoluminescence quantum yields over 90% but also narrow bandwidth enhance rate constant reverse intersystem crossing process, well suppress spectral broadening devices. Benefiting from excellent properties good inhibition broadening, OLEDs based on achieve highest external 27.7% smallest fwhm 24 among emitters.