Effect Of Anode Modification On The Performance Of Simplified Organic Light-Emitting Diodes

With the fast development of science and technology and display technology continued progress,organic light emitting diode(OLED)display technology has also been developed rapidly.It has the advantages of autoluminescence,large viewing angle,low power consumption,fast response and flexible and so on,which is recognized as a new generation of display technolog.However,the complex structure and high production cost of OLED have become the main constraint on its commercial production.In order to simplified device fabrication process and reduce the production cost,the development of high efficiency single layer OLED has important practical value for reducing the cost of OLED devices.In this paper,we mainly study the effect of anode interface modification on the performance of simplified OLEDs.Main works are as follows:1.Based on the structure of ITO/ HIL/ TPBi: Ir(ppy)3/ LiF/ Al(HIL=V2O5,MoO3,PEDOT: PSS),we discuss the effect of different hole injection layers on the device performance.By comparison,it is found that that the transport ability of these three HILs was as follows: V2O5 >MoO3 >PEDOT: PSS,but the performance of PEDOT: PSS as anode modification layer is the highest,gives the maximum current efficiency of 41.25 cd/A,maximum power efficiency of 30.79 lm/W.Indicated that that the hole injection layer plays an important role in OLEDs that the anode modification is not only to reduce the hole injection barrier between electrode and organic layer,but also can improve carrier injection balance in emitting layer.2.Study the performance of simplified structure OLEDs based on chlorinated ITO.The ITO anodes were treated with chloroform,o-dichlorobenzene(o-DCB)and chlorobenzene by UV radiation.Due to the different molecular composition and molecular structure of the three solvents,the relationship between the three materials and the UV treatment time was studied.In three chlorination solvents,the device with ITO modified by o-dichlorobenzene with UV radiation for 5 min gives the maximum luminance efficiency 33.48 cd/A,and maximum luminance efficiency 27.51 lm/W.3.The effect of the performance of simple structure devices based on Mo O3 and C60 mixed as hole buffer layer was studied.By mixed C60 which has blocking effect on the hole with MoO3 in a certain proportion as hole buffer layer to play a role in the passivation of hole injection.It was found that with the increasing of the ratio of C60 in buffer layer,device current density reduced significantly.The device showed the maximum current efficiency 35.52 cd/A and maximum power efficiency 31.87 lm/W when the ratio of MoO3 and C60 was 1:3 with 1.6 nm thickness hole buffer layer,which is better than the device with pure MoO3 HIL.