Abstract The mixed cohosts of electron transport host (E-host): 4,40-bis(carbazol-9-yl)biphenyl (CBP) have been comparatively investigated for an efficient green fluorescent organic light emitting diode (OLED) doped with a thermally activated delayed fluorescence (TADF) emitter (4s,6s)-2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN). The E-host:CBP systems significantly enhance the electroluminescent (EL) properties. After doping E-host, the lifetime of the emissive layer decreases and the surface becomes smoother, together with the impedance decreases for one magnitude and the hole-injection depresses. The charge balance and improved interface both contribute to the EL performance enhancement. Here we develop a universal mixed host system suitable to most of emitters.

中文翻译：

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高效绿色延迟荧光有机发光二极管中基于双极矩阵的混合主体的研究

摘要 电子传输主体 (E-host): 4,40-双(咔唑-9-基)联苯 (CBP) 的混合共主体已被比较研究用于高效绿色荧光有机发光二极管 (OLED)激活延迟荧光 (TADF) 发射器 (4s,6s)-2,4,5,6-四 (9H-咔唑-9-基) 间苯二甲腈 (4CzIPN)。E-host:CBP 系统显着增强了电致发光 (EL) 特性。掺杂 E-host 后，发光层的寿命降低，表面变得更光滑，同时阻抗降低一个数量级，空穴注入降低。电荷平衡和改进的界面都有助于提高 EL 性能。在这里，我们开发了一个适用于大多数发射器的通用混合宿主系统。