Key Laboratory of Photochemistry, Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 100190, Beijing, China.
School of Chemical Sciences, University of Chinese Academy of Sciences, 100049, Beijing, China.
Angew Chem Int Ed Engl. 2023 May 8;62(20):e202302160. doi: 10.1002/anie.202302160. Epub 2023 Apr 12.
The development of circularly polarized electroluminescence (CPEL) is currently hampered by the high difficulty and cost in the syntheses of suitable chiral materials and the notorious chirality diminishment issue in electrical devices. Herein, diastereomeric Ir and Ru complexes with chiral (±)-camphorsulfonate counteranions are readily synthesized and used as the active materials in circularly polarized light-emitting electrochemical cells to generate promising CPELs. The addition of the chiral ionic liquid (±)-1-butyl-3-methylimidazole camphorsulfonate into the active layer significantly improves the device performance and the electroluminescence dissymmetry factors (≈10 ), in stark contrast to the very weak circularly polarized photoluminescence of the spin-coated films of these diastereomeric complexes. Control experiments with enantiopure Ir complexes suggest that the chiral anions play a dominant role in the electrically-induced amplification of CPELs.
圆偏振电致发光 (CPEL) 的发展目前受到两个方面的阻碍：一个是合适手性材料的合成难度大、成本高，另一个是电致器件中存在严重的手性衰减问题。在此，通过手性（±）-樟脑磺酸阴离子合成了非对映异构体 Ir 和 Ru 配合物，并将其作为手性发光电化学电池中的活性材料，以产生有前景的 CPEL。将手性离子液体（±）-1-丁基-3-甲基咪唑樟脑磺酸加入到活性层中，可显著提高器件性能和电致发光不对称因子（≈10），与这些非对映异构体配合物旋涂薄膜的非常弱的圆偏振光致发光形成鲜明对比。使用对映纯 Ir 配合物的控制实验表明，手性阴离子在手性的电诱导放大 CPEL 中起着主导作用。
