Blue Fluorescence And Yellow Phosphorescence Monochromatic Organic Light-emitting Diodes

Organic light-emitting diodes(OLED)is praised as a(dream display).OLED is widely used in various fields due to its great advantages,such as spontaneous light,low energy consumption,flexibility,rapid response,energy-saving,environmental protect-tion and so on.OLED research can be dated back to the 1950 s,but it was not until the end of the last century that OLED performance improved significantly and entered in the industrial application of more fields.The two most important application of OLED are display and lighting,and blue light is extremely critical when realizing panchroma-tic display devices,but the efficiency of blue light devices and the high efficiency of deep blue light materials are particularly serious problems.With the in-depth study of organic light-emitting devices,from simple single-layer structure to a variety of multylayer structure,the structural design of OLED is more diversified.However,various complex structures are extremely difficult for the preparation of OLED.In view of the above problems,this paper the first studies blue fluorescence devices and the “subjectobject-subject” luminescent layer structure of the yellow phosphorescent devices.The main research contents are as follows:(1)The blue fluorescent devices were studied.Firstly,4,4',4"-Tris(carbazol-9-yl)triphenylamine(TCTA)was used as hole transport layer,1,3,5-Tri(m-pyridin-3-ylphenyl)benzene(Tmpypb)as electronic transport layer,and four kinds of fluorescent materials as single luminous layer to make a group of devices,and the respective properties of the four kinds of materials were analyzed,Secondly,in order to understand the four kinds of fluorescent material in carrier transmission case,we made the four kinds of fluorescent material of electrons and holes only one carrier device,and the last in order to further improve the efficiency of blue fluorescent devices,a fluorescent material with better performance was selected,and a blue fluorescent device with higher efficiency was made by using the method of host and guest doping.The maximum efficiency of the device was 7.81 cd /A and 6.67 lm/W,respectively,and the low open voltage of 2.97 V was achieved.(2)The luminescence layer structure of the device was studied by using the "subject-object-subject" phosphor ultrathin layer structure.Firstly,4,4',4"-Tris(carbazol-9-yl)triphenylamine(TCTA)was used as hole transport layer,1,3,5-Tri(m-pyridin-3-ylphenyl)benzene(Tmpypb)as electronic transport layer,1,3-2-9-carba-zole base benzene(1,3-Di-9-carbazolylbenzene(MCP)as a subject layer,and PO-01 as phosphorescence ultra-thin layer to make a group of yellow phosphorescent devices.In order to further improve the performance of the device,the double doping method was subsequently adopted as the subject layer,and realized the maximum efficiency of 62.5 cd/A and 54.19 lm/W,respectively.