Design,Synthesis And Electroluminescence Properties Of Organic Blue Light Materials Based On Anthracene

Since the development of organic electroluminescent diode(OLEDs)materials,the research on red light materials and green light materials has been very mature.Blue light materials with excellent comprehensive performance need to be further developed,especially the blue light materials with high efficiency,low roll-off and low processing cost.In this thesis,the most potential anthracene is selected as the fluorescent emission core,and four blue fluorescent organic materials are designed and synthesized.We systematically studied their electroluminescence properties:1.The Cz An TPh molecule was successfully synthesized by using m-terphenyl as the hindering group and carbazole as the electron donor to modify anthracene.And the comparative molecules DTPh An and TPAAn TPh were synthesized.Then a series of physical tests such as thermodynamics,electrochemistry,UV-Vis absorption spectroscopy and fluorescence emission spectroscopy were performed on these three molecules,and new types of non-doped devices and doped devices were prepared,and the device performance was tested.It is found that the simultaneous introduction of carbazole and terphenyl can effectively inhibit the aggregation between molecules.At the same time,theoretical calculations show that this molecular design does not significantly expand the degree of conjugation of anthracene molecules to ensure deep blue light emission.Non-doped devices with Cz An TPh as the light-emitting layer can achieve deep blue emission at CIE(0.153,0.069),and its EQE_max can reach 3.32%,and have very low efficiency roll-off;doped devices can achieve purple-blue emission at CIE(0.157,0.047),and its EQE_max is increased to 4.20%,but the efficiency roll-off is improved.2.The TPAAn TPE,Cz An TPE and PIAn TPE molecules were successfully synthesized,by using tristyrene as the space-steric group and triphenylamine/carbazole/phenanthrimidazole as the electron donor,and respectively modifying the 9th and 10th positions of anthracene,Then a series of physical tests such as thermodynamics,electrochemistry,UV-Vis absorption spectroscopy,fluorescence emission spectroscopy,solvation spectroscopy,AIE characteristic fluorescence spectroscopy and single crystal X-ray diffraction were performed on the three molecules,and a new type of non-doped The performance of miscellaneous devices and doped devices has been tested.It is found that the introduction of TPE can effectively control the aggregation between molecules.Through theoretical calculations,it is found that TPE effectively expands the degree of conjugation of anthracene molecules,resulting in failure to get the deep blue emission.TPAAn TPE,Cz An TPE and PIAn TPE non-doped devices have achieved higher efficiencies.EQE_max is4.13%,4.04%and 4.46%.And the color coordinates are(0.162,0.271),(0.174,0.213)and(0.178,0.234).And the efficiency roll-off of TPAAn TPE,Cz An TPE and PIAn TPE is very low when the brightness reaches 100cd/m² and 1000cd/m².The light and color of the doped devices have been optimized,and the color coordinates can reach(0.141,0.209),(0.160,0.178)and(0.152,0.167).EQE_max was increased to 4.83%,4.83%and 5.52%respectively,but the efficiency roll-off was serious.