2-(2-Hydroxyphenyl)benzimidazole-Based Four-Coordinate Boron-Containing Materials with Highly Efficient Deep-Blue Photoluminescence and Electroluminescence
2-(2-Hydroxyphenyl)benzimidazole-Based Four-Coordinate Boron-Containing Materials with Highly Efficient Deep-Blue Photoluminescence and Electroluminescence
复制标题
具有高效深蓝色光致发光和电致发光的2-(2-羟基苯基)苯并咪唑基四配位含硼材料
DOI：
10.1021/ic502815q
复制
发表时间：
2015
影响因子：
4.6
通讯作者：
Yue Wang
中科院分区：
文献类型：
--
作者：
Zhenyu Zhang;Houyu Zhang;Chuanjun Jia;Kaiqi Ye;Hongyu Zhang;Jingying Zhang;Yue Wang
以2-（2-羟基苯基）苯并咪唑为配体，分别与三苯硼烷或溴代二苯并硼烷反应，合成了两个具有深蓝色发光的四配位含硼发光体1和2。硼的螯合作用产生了一个新的π共轭骨架，这使得合成的硼材料具有强烈的荧光，良好的热稳定性和高的载流子迁移率。这两种化合物在溶液中显示深蓝色的发射，具有非常高的荧光量子产率（超过0.70）。更重要的是，样品在溶液和固体状态下显示出相同的荧光，并且由于硼原子和苯并咪唑单元之间的大体积取代基可以有效地分离平坦的发光单元，因此效率保持在高水平（约0.50）。此外，由1或2组成的整洁薄膜表现出相同数量级的高电子和空穴迁移率（通过飞行时间确定）10-4。以1或2为发光材料制备的电致发光器件显示出高性能的深蓝色发光，其CIE坐标分别为（X= 0.15，Y = 0.09）和（X= 0.16，Y = 0.08）。因此，合成的含硼材料是制备高性能深蓝色有机电致发光器件的理想候选材料。
Two novel four-coordinate boron-containing emitters1and2with deep-blue emissions were synthesized by refluxing a 2-(2-hydroxyphenyl)benzimidazole ligand with triphenylborane or bromodibenzoborole. The boron chelation produced a new π-conjugated skeleton, which rendered the synthesized boron materials with intense fluorescence, good thermal stability, and high carrier mobility. Both compounds displayed deep-blue emissions in solutions with very high fluorescence quantum yields (over 0.70). More importantly, the samples showed identical fluorescence in the solution and solid states, and the efficiency was maintained at a high level (approximately 0.50) because of the bulky substituents between the boron atom and the benzimidazole unit, which can effectively separate the flat luminescent units. In addition, neat thin films composed of1or2exhibited high electron and hole mobility in the same order of magnitude 10–4, as determined by time-of-flight. The fabricated electroluminescent devices that employed1or2as emitting materials showed high-performance deep-blue emissions with Commission Internationale de L’Eclairage (CIE) coordinates of (X= 0.15,Y= 0.09) and (X= 0.16,Y= 0.08), respectively. Thus, the synthesized boron-containing materials are ideal candidates for fabricating high-performance deep-blue organic light-emitting diodes.