Simplified p-i-n organic light-emitting diodes using an universal ambipolar material

A simplified p-i-n organic light-emitting diode with only one organic material in the emitting layer and the charge transport layer was developed. A blue light-emitting material, 2-methyl-9,10-di(2-naphthyl) anthracene (MADN), was used as a host in the light-emitting layer, a hole transport material and an electron transport material. P type and n type dopants were doped into the MADN and the p-doped and n-doped MADN layers were used as charge transport layers to fabricate p-i-n type devices. The p-i-n type simple blue device with the MADN in all organic layers showed better power efficiency than the conventional organic light-emitting diodes.