White organic light-emitting diodes using bis(2,4-dimethyl-8-quinolinolato) (triphenylsilanolato) aluminum(III) as a new hole-blocking layer

The balanced white-emission of the organic light-emitting diodes (OLEDs), consisted of a deep blue N,N′W-diphenyl-N,N′-bis(1-naphthyl)-(1, 1′-biphenyl)-4,4′-diamine (NPB) emitter and a new orange emitter made of the bis(2,4-dimethyl-8-quinolinolato)(triphenylsilanolato) aluminum(III) (24MeSAlq) doped with a red fluorescent 4-(dicyanomethylene)-2-tertbutyl-6-(1, 1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) was tuned by varying a thickness of a DCJTB-doped 24MeSAlq material. For the white OLED with 10-nm-thick DCJTB (0.5%) doped 24MeSAlq, the maximum luminance of about 29,700 Cd/m² is obtained at 15V. Also, Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.32,0.28) at about 100 Cd/m², which is very close to white light equi-energy point (0.33,0.33), could be obtained.