Synthesis And Properties Of Aryl Sulfide Pyridazine And Tridentate Ir(?)Complex

The quantum efficiency of phosphorescent OLEDs can reach 100%,which is much larger than traditional fluorescent OLEDs,which has caused widespread concern.However,there are still many problems with phosphorescent OLEDs,such as luminescence quenching,poor stability of the device,and the like.In order to improve the problem of luminescence quenching,the first part of this paper introduced dimethyl thiophenol as a sterically hindered group on the pyridazine derivative,and synthesized two ring metal ruthenium complexes,Ir1 and Ir2.On this basis,the S on the ring metal ligand was partially oxidized to the sulfoxide group to obtain the complexes Ir3 and Ir4 to study the effect of charge property change on the properties of the complex.The structure of the complex was confirmed by nuclear magnetic resonance,high resolution mass spectrometry,and single crystal.The maximum emission wavelengths of the complex Ir1-Ir4 are at 524 nm,536 nm,529nm and 539 nm.The complex Ir2 is red-shifted compared to Ir1.This is because the presence of the ancillary ligand reduces the energy level difference,the ligand field is weak,and the spectrum is red-shifted.Similarly,the Ir4 wavelength is longer than Ir3.Compared with Ir1,the Ir3 wavelength is redder.This is because the S atom is oxidized and becomes electron-deficient from the electron-rich group,which lowers the LUMO level and reduces the energy level difference.Similarly,the Ir4wavelength is longer than Ir2.The complexes Ir1 and Ir2 were doped to the host material CBP at different concentrations and the device 1 and the device 2 were fabricated.The starting voltages of devices 1 and 2 are 4.0 V and 3.5 V,respectively.The maximum brightness is 7948 cd/m2,8913 cd/m2,and the maximum current efficiencies are 42.9 cd/A and 44.2 cd/A,respectively.The maximum external quantum efficiencies are 10.7%and 11.7%,respectively.Device 2 performs slightly better.In order to solve the stability problem of the device,the second part of this paper successfully synthesized a series of double tridentate metal ruthenium complexes Ir5-Ir9 in decalin by ligands with negative monovalent ligand and negative divalent N^NH structure.The structure of the complex was confirmed by nuclear magnetic resonance and high resolution mass spectrometry.The maximum emission wavelengths of the complex Ir5-Ir9 were 527 nm?Ir9?,580 nm?Ir8?,586 nm?Ir7?,601 nm?Ir6?and 604 nm?Ir5?.Compared with Ir5,Ir6 has a slight red shift compared with Ir7,which is Ir5.The push-electron radical on the negative monovalent ligand of Ir7 pushes up LUMO and increases the energy level difference.Compared with Ir7,Ir7 showed a large blue shift,because the trifluoromethyl group pulling electrons lowered the HOMO level and increased the energy.Similarly,Ir8 also has a blue shift compared to Ir6.The complex Ir9 was doped into the host material mCP at different concentrations and the device was fabricated.The device doping concentration was2%,the ignition voltage was 3.9 V,the device reached a maximum brightness of 9472cd/m2,and the maximum current efficiency was 23.7 cd/A.The external quantum efficiency was 14.4%.Due to the high toxicity of Be²⁺,it is important to detect strontium content by means of high selectivity and sensitivity.In the third part,Ionic iridium complex 10and neutral iridium complex 11 were synthesized with4'-?2-benzothiazolyl?benzo-9-crown-3 ether primary ligand and different ancillary ligands.The structures of the complexes were confirmed by NMR,high resolution mass spectrometry,and X-ray structural analysis.All these complexes show a strong kelly phosphorescent emission.The photoluminescence spectra of complex 10 and complex 11 in PMMA(1 _wt%)show emission maximum at 535 nm and 541 nm,respectively.Their quantum efficiencies were 10.8%and 45.0%and the luminescence lifetimes were 3.01?s and 2.58?s.By means of the cyclic voltammogram,the HOMO levels of complex 10 and 11 were calculated to be-5.60 eV and-5.35 eV.Both complexes display a high selectivity for Be²⁺among relevant metal ions,and exhibit luminescence enhancement effects in the presence of Be²⁺.The stoichiometric ratio of iridium complexes responding to Be²⁺was determined to be 1:2,and the detection limit is down to 6.0?mol/L.The ionic iridium complex 10 has good antidisturbance,however the neutral iridium complex 11 is greatly interfered by Al³⁺.