Low operating voltage and long lifetime organic light-emitting diodes with vanadium oxide (V2O5) doped hole transport layer

摘要

We report low operating voltage and long lifetime organic light-emitting diodes (OLEDs) with a vanadium oxide (V2O5)-doped N,N’-di(1-naphthyl)- N,N’-diphenylbenzidine (α-NPD) layer between indium tin oxide and α-NPD. At a luminance of 1000 cd/m2, V2O5 doped α-NPD device shows a operation voltage of 5.1V, while the device without V2O5 shows 5.8V. The V2O5 doped α-NPD device also shows a longer lifetime and smaller operation voltage variation over time. It is suggested that the improved device performance can be attributed to the higher hole-injection efficiency and stability of the V2O5– doped α-NPD layer.