The Research On White Organic Light-emitting Diodes

ABSTRACT:This paper reports a systematical investigation in fabrication of white light organic electroluminescent devices in combination of fluorescent and phosphorescent materials. First I use the new material TDAF as blue material to design single layer, dual layer, triple layer white light-emitting diodes (oleds), but the devices’ performance are not very ideal, only get into the white area. So we change the material, the formation of exciplex in multilayered structure or doping in the device was carefully explored. In these devices, OXD-7was acted as blue layer, Ir(MDQ)2acac used as a red dopant and doped into a host material to make dual-band white OLED. It was found that the formation of exciplex caused a bathochromic shift of OXD-7emission, which in turn undermined the device performance. This problem can be solved by inserting TDAF as an intermediate layer, which effectively inhibited the formation of the exciplex and hence the red shift. The device performance can them be improved.