Phosphorescence quenching by conjugated polymers.
Phosphorescence quenching by conjugated polymers.
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DOI：
10.1021/ja0343297
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发表时间：
2003-06
影响因子：
15
通讯作者：
M. Sudhakar;P. Djurovich;T. Hogen-esch;M. Thompson
中科院分区：
文献类型：
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作者：
M. Sudhakar;P. Djurovich;T. Hogen-esch;M. Thompson
以芴三聚体（F3）作为共轭材料模型，研究了磷光体与共轭聚合物之间的能量转移。所研究的磷光体为双环金属化铱配合物（FP、PPY、BT、PQ和BTP），其三线态能量分别为2.6、2.4、2.2、2.1和2.0 eV（基于磷光光谱）。发光猝灭的斯特恩 - 沃尔默分析表明，从FP或PPY到F3的能量转移是一个放热过程，斯特恩 - 沃尔默猝灭常数（kqSV）接近10⁹ M⁻¹ s⁻¹，而从BT、PQ和BTP的能量转移是吸热的（kqSV = 10⁷ - 10⁶ M⁻¹ s⁻¹）。基于上述结果，F3的三线态能量估计小于2.3 eV（530 nm）。这项研究表明，通常具有比F3更低的T1能量的共轭聚合物，在包含这些及相关磷光掺杂剂的薄膜和有机发光二极管（OLEDs）中也应该会猝灭磷光发射。
Energy transfer between phosphors and conjugated polymers was investigated using a fluorene trimer (F3) as a model conjugated material. The phosphors studied were bis-cyclometalated iridium complexes (FP, PPY, BT, PQ, and BTP), with triplet energies of 2.6, 2.4, 2.2, 2.1, and 2.0 eV, respectively (based on phosphorescence spectra). Stern-Volmer analysis of luminescent quenching shows that energy transfer from either FP or PPY to F3 is an exothermic process with Stern-Volmer quenching constants (kqSV) of near 109 M-1 s-1 while energy transfer from BT, PQ, and BTP is endothermic (kqSV = 107-106 M-1 s-1). On the the basis of above results, the triplet energy of F3 is estimated to be less than 2.3 eV (530 nm). This study suggests that conjugated polymers, which typically have lower T1 energies than F3, should also quench phosphorescent emission in thin films and organic light-emitting diodes (OLEDs) incorporating these and related phosphorescent dopants.