新型蓝色磷光嘧啶铱(Ⅲ)配合物的合成及发光性质

摘要

We designed and synthesized two new indium ( IH ) diazine complexes [ (DFPPM)2IrCl-(PPh3)] and [ (DFPPM)2Ir(CN) (PPh3) ], where Ph = pheny], containing2-(2,4-difluorophenyl)-pyrimidine (DFPPM) as the cyclometalated ligands. OLEDs with iridium( III ) diazine complexes as phosphor have high-efficiency and long luminance half-life, however, diazine compounds show a significantly redshift of the emission band than pyridine compounds. Therefore, it will be a great challenge to synthesize blue phosphorescent materials with diazine compounds as ligands. The complexes were characterized by nuclear magnetic resonance ( NMR) spectroscopy and mass spectrometry (MS) and their photophysical properties were investigated by UV-Vis spectroscopy and photolumi-nescence (PL) technique. The PL spectrum of [ (DFPPM ),IrCl(PPh3) ] in solution has its maximum emission peak at 472 nm and 489 nm, whereas [ ( DFPPM) 2Ir( CN) (PPh3) ] has its maximum emission peak at 447 nm and 472 nm. The luminescence of [ (DFPPM) 2IrCl( PPh3) ] shifts lothe blue region compared to that of (DFPPM)2Ir(acac) , indicating that the HOMO-LUMO gap is increased due to the higher ligand field strength of the phosphine. Compared with [ ( DFPPM )2IrCl-(PPh3) ] , [ ( DFPPM)2 Ir( CN) ( PPh3) ] shows a significantly blue-shift of the emission band. The ligand field strength of CN is larger than Cl due to its strong a donor and -rr acceptor ability. This causes larger splitting of the d-orbital and consequently more lowering of the metal-centered HOMO. Complex of ( DFPPM)2lr( CN) ( PPh3) emits deep blue light with Commission Internationale de l'Eclairage (CIE) coordinates of (0. 14, 0. 15). Electroluminescence (EL) device was fabricated when the complex of [ ( DFPPM) 2Ir( CN) (PPh3) ] was doped into polymer host polyvinylcarbazole (PVK). Compared to the photoluminescence spectrum, a red-shifted of emission was observed from the electroluminescence spectrum. The reason of red-shift of EL spectra is in progress.%设计并合成了以2-(2,4-二氟苯基)嘧啶( DFPPM)为主配体的两种新型二嗪铱配合物[(DFPPM)2 IrCl-( PPh3)](Ph:苯基)和[(DFPPM)2Ir(CN)( PPh3)],用核磁共振(NMR)和质谱等方法对其进行了表征,并用紫外-可见吸收光谱和光致发光光谱对其光学性质进行了研究.光致发光光谱结果显示:配合物[(DFPPM)2IrCl( PPh3)]的发射峰波长为472 nm和489 nm;而配合物[(DFPPM)2 Ir( CN)( PPh3)]的发射峰波长为447 nm和472 nn,1931CIE色度坐标为(0.14,0.15),是一种深蓝色磷光材料.以[(DFPPM)2Ir-(CN)( PPh3)]为客体材料、PVK为主体材料制备了电致发光器件,研究了其电致发光光谱.结果表明,电致发光光谱与光致发光光谱相比有较大程度的红移.