Blu-ray Dendritic Phosphorescent Iridium Complex Design, Synthesis And Performance Studies

In order to further improve the performance of materials, the key problem need to be solved is to develop new types of blue processing solution phosphorescent materials. The heavy metals can effectively enhance the spin coupling to improve the luminous efficiency of the complex and the high internal quantum efficiency can reach 100%. At the same time, complex in solution processing and industrial production can be largely reduced production costs.In this paper, the classic blue light-emitting iridium complexes are set as light-emiting core and connect with high T1 and high carrier mobility carbazole branch structure. GB0, GB1, GB2, BB0, BB1 and BB2, six blue phosphorescent complexes are synthesized, and they are confirmed by NMR and MS characterization methods. Those realized the host-guest integration, thus avoiding phase separation caused by the previous doping. The study of the thermal properties of these materials suggested that the introduction of carbazole units surrounding the core can effectively enhance the compound's Tg and decomposition temperature (Td). The photoluminescence spectra of film state of BB2 and GB2 proved that they could inhibit the aggregation, so they could get a better blue emission peak in film state. What is more? We can see that the electrochemical behavior of all six compounds have a good redox behavior.We synthesis three new rigid structure complexes by modifying the pyridine groups of 2,4-difluorophenyl pyridine. Solution state photoluminescence spectra of complex which the carbazole in the 4 position of pyridine group of the complex is bluer than the 5 position. Electron diphenyl phosphate oxygen groups makes the spectral red shift occurs. The electrochemical suggest that the introduction of the carbazole and diphenyl phosphate oxygen do not affect the HOMO, while that lower the LUMO. The results provide a favorable basis for the new design of blue light-emitting complex.