Designedly Syntheses And Phosphorescence Properties Of Cyclometalated Iridium(?) Compounds With Modified Pyridazines And Homolepic Nitrogen-coordinated Platinum(?) Compounds With Modified Carbazoles

In recent years,the rapid development of OLED has made organic phosphorescent materials attract a lot of attention.The prepatation of high-performance phosphorescent materials has become the focus of research.A series of cyclometalated iridium(?)compounds Ir(dptpp)3?Ir(mbtpp)3?Ir(pbtpp)3 were obtained from reaction of pyridazine ligands with different substituent groups(trifluoromethyl group,phenoxy)and Ir Cl3·3H2O.The phosphorescence properties of compounds were investigated in this thesis.We found that the trifluoromethyl group with electron-withdrawing effect can promote the synthesis of cyclometalated iridium(?)compounds.Compounds were investigated spectroscopically characterized and established by single-crystal X-ray diffraction.The emission wavelength of compounds is between 582.5 nm-630 nm,which is orange to red light region.The OLED was fabricated by doping the compound into the host material m CP.The maximum external quantum efficiencies of devices were 7.5%,9.5%,and 7.4%,respectively.The phenomenon that the brightness of devices declines slowly indicates the triplet quenching of the compounds is weak.This shows that the trifluoromethyl group improves the performance of the device,especially,the compound Ir(mbtpp)3 has the best performance.The iridium(?)compounds with polydentate ligands also attracted the attention of researchers due to their high quantum efficiency.In this paper,a bistridental iridium(?)compounds(pbpy)Ir(mptppy)with 3+3 coordination was synthesized.Its structure has stronger rigidity and higher luminous efficiency.The compound was investigated photoluminescence spectroscopy and the orange-red emission wavelength at 589.5 nm.The lifetime of compound is 1.2 ?s and the quantum efficiency of compound is 16.5%.Meanwhile,the device that fabricated by doping the compound into the host material.The maximum external quantum efficiency of device was 13.4%.And the device performance are consistent with the typical diode characteristics.The results show that the four iridium(?)compounds can be used as excellent phosphorescent light-emitting materials,which are expected to be applied in OLEDs.In this paper,a series of diimine platinum(?)compounds(pbpy)Pt,(sbbpy)Pt,(dkz)Pt were synthesized.The basic bipyridine ligand was modified by different steric hindrance groups(carbonyl,spiro and carbazole groups).Platinum(?)compounds were investigated spectroscopically characterized.The photoluminescence spectroscopy of compounds show that the emission wavelength is between 524nm-620 nm.The lifetime of the compounds is decreasing in turn.And the compound(dkz)Pt has the shortest lifetime is 0.9 ?s.The carbazole group makes the compound structure more stable,which makes device has better performance.The development of platinum(?)compound is hindered due to their easy to accumulate.The compound(sbbpy)Pt was established by single-crystal X-ray diffraction and the diatance between the Pt-Pt was 11.0881 ?,which proved that the spiro group can inhibit accumulate.Meanwhile,we studied the AIEE properties of the compounds and tested the fluorescence intensity of compound in solutions with different water content.And the fluorescence intensity was increased along with increasing of water content.The fluorescence intensity was enhanced by 35 times.This property is advantageous for the application of platinum(?)compounds in devices.