Organic light‐emitting diodes (OLED) are gaining attention and making a significant contribution to the area of lighting and displays technology. The synthesis of new materials that can act as a host as well as emissive materials is crucial and efforts have been made in this direction in this research. Here, four star‐shaped fluorophores, with a donor–acceptor (D–A) structure and with triphenylamine and phenanthroimidazole groups with different substitutions at the N₁ position of the imidazole moiety, were designed and synthesized. Synthesized fluorophores showed sufficient thermal stability (10% T_d in the range 230–280°C). Ultraviolet–visible (UV–vis) spectra of the fluorophores showed multiple absorption bands (bands in the UV region, due to π–π* transitions of the conjugated aromatic portion) and all fluorophores showed blue emission in dichloromethane solution. Electrochemical analysis indicated that all fluorophores had excellent oxidation and reduction characteristics. Theoretical calculations were also performed to better understand the structural and electronic properties of the synthesized fluorophores. All fluorophores had higher triplet (T₁) energy (ranging from 2.49–2.52 eV) than the widely used green (Ir(ppy)₃ –2.4 eV) and red (Ir (piq)₂ acac – 2.2 eV) dopant materials. These results indicated that these fluorophores would be useful as host materials for efficient green and red phosphorescent OLEDs.

中文翻译：

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用于有机发光二极管的基于苯并咪唑的生色团：合成，光物理和理论研究。

有机发光二极管（OLED）受到关注，并在照明和显示技术领域做出了重大贡献。既可以用作主体又可以用作发光材料的新材料的合成至关重要，并且在此研究中已朝这个方向做出了努力。在这里，设计并合成了四个具有供体-受体（D–A）结构，在咪唑部分的N ₁位置具有不同取代基的三苯胺和菲并咪唑基团的星形荧光团。合成的荧光团显示出足够的热稳定性（T _d为10％温度范围为230–280°C）。荧光团的紫外-可见（UV-vis）光谱显示了多个吸收带（由于共轭芳族部分的π-π*跃迁，在紫外区出现了吸收带），并且所有荧光团在二氯甲烷溶液中均呈蓝色发射。电化学分析表明，所有荧光团均具有优异的氧化还原性能。还进行了理论计算，以更好地了解合成荧光团的结构和电子性质。与广泛使用的绿色（Ir（ppy）₃ –2.4 eV）和红色（Ir（piq）₂）相比，所有荧光团的三重态（T ₁）能量更高（范围为2.49–2.52 eV）。acac – 2.2 eV）掺杂材料。这些结果表明，这些荧光团可用作有效的绿色和红色磷光OLED的主体材料。