Abstract
The invention provides a novel polymer light-emitting diode (LED) which can emit near white light with a broad spectrum, which LED comprises a transparent electrode as an anode, a metal electrode as a cathode, an organic light-emitting layer, and a hole transport layer and/or an electron transport layer, wherein the organic light-emitting layer contains a blend of a blue light-emitting poly (paraphenylene vinylene) copolymer and a red light-emitting alkoxy-substrituted PPV derivative in an appropriate relative ratio, such that, the novel LED can emit sun light-like yellowish white light with an broad electroluminescent spectrum covering the whole range of visible light without varying as the voltage increased. And wherein, by virture of introducing a hole transport layer and/or electron transport layer, the turn-on voltage of the device can be lowered and emission efficiency thereof is increased.