含区位异构氨基萘酰亚胺配体的环Ir配合物三重态光敏剂的合成、光物理性质以及在三重态湮灭上转换中的应用

Visible light-harvesting cyclometalated Ir(Ⅲ) complexes showing long-lived triplet excited states were prepared with regioisomeric aminonaphthaleneimide ligands. The photophysical properties of the complexes were studied with steady state and time-resolved spectroscopies, as well as DFT calculation. Compared to the known cyclometalated Ir(Ⅲ) complexes, the new complexes show ligand-localized triplet excited state (3IL state), instead of the normal 3MLCT state. The two complexes with regioisomeric NI ligands show drastically different photophysical properties, such as phosphorescence quantum yields. The complexes were used as triplet photosensitizer for triplet-triplet annihilation (TTA) upconversion. TTA upconversion quantum yield up to 19.3% was observed. These results are useful for preparation of visible light-harvesting Ir(Ⅲ) complexes and for the study of the triplet excited state of organic chromophores.