以铱配合物为核、聚(芴-咔唑)为臂的白光星型磷光聚合物

doi:10.11944/j.issn.1000-0518.2020.01.190150

摘要/Abstract

摘要：

设计合成了以苯基苯并咪唑和吡啶三唑为配体的高效的黄绿光铱配合物(M1),并通过Suzuki缩聚反应制备了以磷光铱配合物客体为中心核、蓝光荧光聚(芴-咔唑)主体为臂的星型磷光聚合物(P2.5、P5.0和P10),着重对M1和聚合物的发光性能、电化学性能及热稳定性能进行研究。结果表明,M1具有较高的荧光量子效率(32.06%),其荧光寿命为1.09 μs,聚合物荧光寿命为2.223.93 μs,均表现为磷光;通过调节主客体的比例,利用主客体的部分能量转移机制,来实现聚合物的不同光色,发光颜色可从蓝光向黄光变化;当M1摩尔分数为2.5%时,获得的白光聚合物(P2.5)具有较好的发光性能和热稳定性能,色坐标为(0.30,0.32),位于白光区域,其最高占有轨道(HOMO)能级和最低未占有轨道(LUMO)能级分别为5.49和2.43 eV,荧光量子产率为14.3%,荧光寿命为2.22 μs。

关键词: 聚(芴-咔唑), 铱配合物, 星型聚合物, 磷光, 白光

Abstract:

An efficient green-yellow light iridium complex based on 2-(4-brominephenyl)-1-octyl-benzimidazole as cyclometalated ligand and 3-bromine-5-(pyridin-2-yl)-1H-1,2,4-triazole as ancillary ligand was synthesized. A series of novel star-shape phosphorescent polymers (P2.5, P5.0 and P10) was synthesized by employing the iridium complex as the core guest and the poly(fluorine-carbazole) as the arm host through Suzuki cross-coupling. The properties of the iridium complex and polymers were studied. The results showed that the iridium complex emitted green-yellow light with peaks at 490,526 and 565 nm and its fluorescent quantum efficiency was 32.06%. Fluorescent lifetimes for the iridium complex and the polymers are in the microsecond regime (1.093.93 s). Such long-lived excited states clearly suggest that the emitting state has triplet phosphorescent emission. The yellow light intensity was enhanced with the increasing of iridium complex content, indicating that there exists partial energy transfer from host to guest, and the emission color of polymers shifts from blue to yellow by adjusting the proportion of the iridium complex. When the mole fraction of iridium complex reached to 2.5%, the white-light polymer (P2.5) was obtained, the CIE1931 chromaticity coordinate was (0.30, 0.32), the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels were 5.49 and 2.43 eV respectively, fluorescent quantum efficiency was 14.3%, and fluorescent lifetime was 2.22 s. The polymer having good thermal stability can satisfy the requirements of luminescent materials.

Key words: poly(fluorine-carbazole), iridium complex, star-shape polymer, photoluminescence, white-light emission

曾惠卷, 林美娟, 刘超, 陈龙杰, 张语珊, 凌启淡. 以铱配合物为核、聚(芴-咔唑)为臂的白光星型磷光聚合物[J]. 应用化学, 2020, 37(1): 16-23.

ZENG Huijuan, LIN Meijuan, LIU Chao, CHEN Longjie, ZHANG Yushan, LING Qidan. White Phosphorescent Star-Shape Polymers Derived from Poly(fluorene-carbazole) with Green-Yellow Iridium Complex as the Cores[J]. Chinese Journal of Applied Chemistry, 2020, 37(1): 16-23.

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