Bis-Zn-II salphen complexes bearing pyridyl functionalized ligands for efficient organic light-emitting diodes (OLEDs)
Bis-Zn-II salphen complexes bearing pyridyl functionalized ligands for efficient organic light-emitting diodes (OLEDs)
复制标题
用于高效有机发光二极管 (OLED) 的带有吡啶基功能化配体的 Bis-Zn-II salphen 配合物
DOI：
10.1039/c7dt00905d
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发表时间：
2017
影响因子：
4
通讯作者：
Wai-Yeung Wong
中科院分区：
文献类型：
--
作者：
Jiang Zhao;Feifan Dang;Boao Liu;Yong Wu;Xiaolong Yang;Guijiang Zhou;Zhaoxin Wu;Wai-Yeung Wong
受基于双希夫碱配体的 ZnII 配合物发射特性的启发，成功合成了带有吡啶基功能化配体的双 ZnII salphen 配合物。它们的光物理特征、电化学行为和电致发光（EL）特性已得到详细研究。功能化的双 ZnII salphen 配合物可以在高达 417 °C 的温度下表现出高热稳定性，并且它们的光致发光（PL）光谱显示出最大发射波长峰在 417 °C 左右。溶液和 PMMA 掺杂薄膜中的波长均为 565 nm。对这些功能化双 ZnII salphen 配合物的纯薄膜的 PL 研究表明，吡啶基功能化配体可以有效降低分子聚集程度，从而提高其发射强度。利用吡啶基功能化配体的载流子注入/传输能力及其树枝状设计，通过简单的溶液处理方法制备的优化的EL器件可以实现3589 cd m−2的峰值亮度（Lmax）、1.46%的最大外量子效率（ηext）、4.1 cd A−1的最大电流效率（ηL）和3.8 lm的最大功率效率（ηp） W−1。这些结果将为开发基于双核 ZnII 配合物的高性能荧光发射器提供重要指导。
Inspired by the emissive features of ZnII complexes based on bis-Schiff base ligands, bis-ZnII salphen complexes bearing pyridyl functionalized ligands have been successfully synthesized. Their photophysical features, electrochemical behavior and electroluminescent (EL) properties have been investigated in detail. The functionalized bis-ZnII salphen complexes can exhibit high thermal stability up to 417 °C, and their photoluminescence (PL) spectra show a maximal emission wavelength peak at ca. 565 nm both in solution and PMMA doped films. The PL investigation of the neat films for these functionalized bis-ZnII salphen complexes indicated that the pyridyl functionalized ligands can effectively reduce the degree of molecular aggregation to enhance their emission intensity. Taking advantage of the charge carrier injection/transporting ability of the pyridyl functionalized ligands and their dendritic design, the optimized EL devices fabricated by a simple solution-processing method can achieve a peak luminance (Lmax) of 3589 cd m−2, a maximal external quantum efficiency (ηext) of 1.46%, a maximal current efficiency (ηL) of 4.1 cd A−1 and a maximal power efficiency (ηp) of 3.8 lm W−1. These results should afford important instructions for exploiting high performance fluorescent emitters based on dinuclear ZnII complexes.