Bright and efficient exciplex emission from light-emitting diodes based on hole-transporting amine derivatives and electron-transporting polyfluorenes

We report highly efficient and bright emission from exciplexes generated between a series of hole-transporting amine derivatives and two electron-transporting fluorene–dicyanophenyl (FCNP) copolymers. These exciplexes were formed at either the interface between tetraphenyldiamine-containing perfluorocyclobutane polymers and the FCNP copolymers, or in the blends of the FCNP copolymers with small molecule amine derivatives such as triphenylamine, N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine, and N,N′-diphenyl-N,N′-bis(1-naphthyl)-[1,1′-biphenyl]-4,4′-diamine. The exciplex emission is largely dependent on the composition of the hole-transporting materials. The best device derived from these exciplexes demonstrated a very low turn-on voltage (2.8 V), a high external quantum efficiency (0.91%), and a high brightness of 3370 cd/m2. The desirable properties of these devices were attributed to the excellent electron transport ability of the FCNP copolymers.

[1]  W. R. Salaneck,et al.  Electroluminescence in conjugated polymers , 1999, Nature.

[2]  A. Jen,et al.  Efficient cyano-containing electron-transporting polymers for light-emitting diodes , 2001 .

[3]  S. Jenekhe,et al.  Excimers and Exciplexes of Conjugated Polymers , 1994, Science.

[4]  R. N. Marks,et al.  Light-emitting diodes based on conjugated polymers , 1990, Nature.

[5]  Shiyong Liu,et al.  White light emission from exciplex using tris-(8-hydroxyquinoline)aluminum as chromaticity-tuning layer , 2001 .

[6]  Yang Yang,et al.  Light-emitting electrochemical cells from a blend of p- and n-type luminescent conjugated polymers , 1997 .

[7]  M. Baldo,et al.  Efficient, Saturated Red Organic Light Emitting Devices Based on Phosphorescent Platinum(II) Porphyrins , 1999 .

[8]  S. Chen,et al.  White light emission from exciplex in a bilayer device with two blue light-emitting polymers , 1998 .

[9]  A. Jen,et al.  Triarylamine-Containing Poly(perfluorocyclobutane) as Hole-Transporting Material for Polymer Light-Emitting Diodes , 2000 .

[10]  A. Jen,et al.  Efficient light-emitting diodes based on a binaphthalene-containing polymer , 1999 .

[11]  F. E. Karasz,et al.  Electroluminescence of pure poly(N‐vinylcarbazole) and its blends with a multiblock copolymer , 1994 .

[12]  Göran Gustafsson,et al.  White light from an electroluminescent diode made from poly[3(4‐octylphenyl)‐2,2′‐bithiophene] and an oxadiazole derivative , 1994 .

[13]  Donal D. C. Bradley,et al.  Angular Dependence of the Emission from a Conjugated Polymer Light‐Emitting Diode: Implications for efficiency calculations , 1994 .

[14]  Jan Kalinowski,et al.  Multicomponent emission from organic light emitting diodes based on polymer dispersion of an aromatic diamine and an oxadiazole derivative , 2000 .

[15]  Y. Shirota,et al.  Exciplex formation at the organic solid-state interface: Yellow emission in organic light-emitting diodes using green-fluorescent tris(8-quinolinolato)aluminum and hole-transporting molecular materials with low ionization potentials , 1998 .

[16]  H. Antoniadis,et al.  Blue-green organic light-emitting diodes based on fluorene-oxadiazole compounds , 1998 .

[17]  Nasser N Peyghambarian,et al.  Exciplex electroluminescence from organic bilayer devices composed of triphenyldiamine and quinoxaline derivatives , 1998 .

[18]  Jan Kalinowski,et al.  Impact of high electric fields on the charge recombination process in organic light-emitting diodes , 2000 .

[19]  Hong Ma,et al.  Organic light-emitting diodes using an in situ thermally polymerized hole transporting layer , 2000 .