An efficient and bright organic white-light-emitting device

A white-light-emitting device has been fabricated with a structure of ITO/NPB/BCP/Alq3/LiF/Al. The hole blocking layer(BCP) result in a mixture of lights from NPB molecules (blue-light) and Alq3 molecules (olivine-light), thereby producing white-light emission. The chromaticity can be readily adjusted by only varying the thickness of the BCP layer. The CIE coordinates of the device are largely insensitive to the driving voltages. The maximum brightness is 5740 cd/m2, the EL efficiency is 2.12 cd/A at the applied voltage of 18 V.