Zou Yang, Hu Jiahao, Yu Mingxin, Miao Jingsheng, Xie Ziyang, Qiu Yuntao, Cao Xiaosong, Yang Chuluo
Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China.
Adv Mater. 2022 Jul;34(29):e2201442. doi: 10.1002/adma.202201442. Epub 2022 Jun 12.
High-color-purity blue and green organic light-emitting diodes (OLEDs) have been resolved thanks to the development of B/N-based polycyclic multiple resonance (MR) emitters. However, due to the derivatization limit of B/N polycyclic structures, the design of red MR emitters remains challenging. Herein, a series of novel red MR emitters is reported by para-positioning N-π-N, O-π-O, B-π-B pairs onto a benzene ring to construct an MR central core. These emitters can be facilely and modularly synthesized, allowing for easy fine-tuning of emission spectra by peripheral groups. Moreover, these red MR emitters display excellent photophysical properties such as near-unity photoluminescence quantum yield (PLQY), fast radiative decay rate (k ) up to 7.4 × 10 s , and most importantly, narrowband emission with full-width at half-maximum (FWHM) of 32 nm. Incorporating these MR emitters, pure red OLEDs sensitized by phosphor realize state-of-the-art device performances with external quantum efficiency (EQE) exceeding 36%, ultralow efficiency roll-off (EQE remains as high as 25.1% at the brightness of 50 000 cd m ), ultrahigh brightness over 130 000 cd m , together with good device lifetime.
由于基于硼/氮的多环多重共振（MR）发光体的发展，高色纯度的蓝色和绿色有机发光二极管（OLED）已得到解决。然而，由于硼/氮多环结构的衍生化限制，红色MR发光体的设计仍然具有挑战性。在此，通过在苯环上对位定位N-π-N、O-π-O、B-π-B对来构建MR中心核，报道了一系列新型红色MR发光体。这些发光体可以简便地模块化合成，通过外围基团可以轻松微调发射光谱。此外，这些红色MR发光体表现出优异的光物理性质，如接近单位的光致发光量子产率（PLQY）、高达7.4×10⁶ s⁻¹ 的快速辐射衰减率（k），最重要的是，半高宽（FWHM）为32 nm的窄带发射。将这些MR发光体应用于磷光敏化的纯红色OLED中，实现了最先进的器件性能，外部量子效率（EQE）超过36%，超低效率滚降（在50000 cd m⁻² 的亮度下EQE仍高达25.1%），超过130000 cd m⁻² 的超高亮度，以及良好的器件寿命。
