Color tunable white organic light-emitting devices with a hybrid 2-methyl-9,10-di(2-naphthyl)anthracene small molecule/poly(2-methoxy-5-(2-ethyhexoxy)-1,4-phenylenevinylene) polymer emitting layer

Abstract

White organic light-emitting devices (WOLEDs) were fabricated utilizing a hybrid poly(2-methoxy-5-(2-ethyhexoxy)-1,4-phenylene vinylene) (MEH-PPV)/2-methyl-9,10-di(2-naphthyl) anthracene (MADN) emitting layer. Nano-sized pores were formed on the surface of the MEH-PPV layer by using a selective etching of polystyrene (PS) in the MEH-PPV:PS blending layer due to the enhancement of the direct hole injection from hole injection layer (HIL) into the MADN layer. The contact area between the HIL and the MADN layer was widened with increasing ratio of the PS in the MEH-PPV:PS blending polymer, resulting in the enhancement of the electroluminescence intensity for MADN. One of the WOLEDs utilizing the polymer with the ratio of 1:2 (0.44, 0.31) met the requirements of the Commission Internationale de l'Eclairage for the white color.