Highly Efficient Color‐Stable Deep‐Blue Multilayer PLEDs: Preventing PEDOT:PSS‐Induced Interface Degradation

Highly efficient and stable blue light emission is observed in novel copolymers that are produced from specially designed building blocks. A PEDOT:PSS-induced chemical degradation of the polymer light-emitting diodes (PLEDs) is identified at the interface, and it is found to be accompanied by a shift in the emission color. A method to prevent this highly undesirable interaction is presented.

[1]  Tae-Woo Lee,et al.  High-efficiency stacked white organic light-emitting diodes , 2008 .

[2]  Ullrich Scherf,et al.  Semiconducting Polyfluorenes—Towards Reliable Structure–Property Relationships , 2002 .

[3]  Yuguang Ma,et al.  Controllable optical, electrical, and morphologic properties of 3,4-ethylenedioxythiophene based electrocopolymerization films. , 2011, Macromolecular rapid communications.

[4]  L. Wong,et al.  Electromigration of the conducting polymer in organic semiconductor devices and its stabilization by cross-linking , 2007 .

[5]  Jie Liu,et al.  Solution-Processed Organic Light-Emitting Diodes for Lighting , 2007, Journal of Display Technology.

[6]  Franco Cacialli,et al.  Molecular-scale interface engineering for polymer light-emitting diodes , 2000, Nature.

[7]  Ullrich Scherf,et al.  On the conjugation length in poly(para‐phenylene)‐type polymers , 1995 .

[8]  D. Moses,et al.  Water/Methanol‐Soluble Conjugated Copolymer as an Electron‐Transport Layer in Polymer Light‐Emitting Diodes , 2005 .

[9]  Donal D. C. Bradley,et al.  Ohmic hole injection in poly(9,9-dioctylfluorene) polymer light-emitting diodes , 2003 .

[10]  Daniel Moses,et al.  High-performance polymer light-emitting diodes fabricated with a polymer hole injection layer , 2003 .

[11]  Magnus Berggren,et al.  The effect of pH on the electrochemical over-oxidation in PEDOT:PSS films , 2007 .

[12]  Yang Yang,et al.  Low‐Work‐Function Surface Formed by Solution‐Processed and Thermally Deposited Nanoscale Layers of Cesium Carbonate , 2007 .

[13]  Jorge Morgado,et al.  Improved efficiency of light-emitting diodes based on polyfluorene blends upon insertion of a poly(p-phenylene vinylene) electron- confinement layer , 2002 .

[14]  Alex K.-Y. Jen,et al.  Thermally crosslinked hole-transporting layers for cascade hole-injection and effective electron-blocking/exciton-confinement in phosphorescent polymer light-emitting diodes , 2006 .

[15]  Malte C. Gather,et al.  Highly color-stable solution-processed multilayer WOLEDs for lighting application , 2010 .

[16]  U. Scherf,et al.  Efficient Polymer Electrophosphorescent Devices with Interfacial Layers , 2006 .

[17]  Yang Yang,et al.  Ultrahigh efficiency green polymer light-emitting diodes by nanoscale interface modification , 2003 .

[18]  Yun Chi,et al.  Crosslinkable Hole‐Transport Layer on Conducting Polymer for High‐Efficiency White Polymer Light‐Emitting Diodes , 2007 .

[19]  Lei Wang,et al.  pH-neutral PEDOT:PSS as hole injection layer in polymer light emitting diodes , 2011 .

[20]  David G Lidzey,et al.  Bright and efficient blue and green light-emitting diodes based on conjugated polymer blends , 2000 .

[21]  Heinz-Georg Nothofer,et al.  Identification of Emissive Interface-Related Defects in Polyfluorene-Based Light Emitting Devices , 2004 .

[22]  J. Reynolds,et al.  Poly(3,4‐ethylenedioxythiophene) and Its Derivatives: Past, Present, and Future , 2000 .

[23]  Richard H. Friend,et al.  Spin-cast thin semiconducting polymer interlayer for improving device efficiency of polymer light-emitting diodes , 2005 .

[24]  E. List,et al.  The Effect of Protonation on the Optical Properties of Conjugated Fluorene-Pyridine Copolymers , 2008 .

[25]  Miin-Jang Chen,et al.  Enhanced OLED performance upon photolithographic patterning by using an atomic-layer-deposited buffer layer , 2008 .

[26]  Walter Riess,et al.  Influence of charge carrier injection on the device performance of blue organic light-emitting diodes , 1998, Photonics West.

[27]  Roman Trattnig,et al.  Deep blue polymer light emitting diodes based on easy to synthesize, non-aggregating polypyrene. , 2011, Optics express.

[28]  Norbert Koch,et al.  Organic electronic devices and their functional interfaces. , 2007, Chemphyschem : a European journal of chemical physics and physical chemistry.

[29]  A. Perro,et al.  The influence of a PEDOT:PSS layer on the efficiency of a polymer light-emitting diode , 2003 .

[30]  Sheng-Fu Horng,et al.  High-efficiency blue multilayer polymer light-emitting diode fabricated by a general liquid buffer method , 2008 .

[31]  Richard H. Friend,et al.  Correlation Between Molecular Structure, Microscopic Morphology, and Optical Propertiesof Poly(tetraalkylindenofluorene)s , 2002 .

[32]  M. Berggren,et al.  Micrometer- and Nanometer-Sized Polymeric Light-Emitting Diodes , 1995, Science.

[33]  F. Jonas,et al.  Poly(alkylenedioxythiophene)s—new, very stable conducting polymers , 1992 .

[34]  Klaus Müllen,et al.  Bridging the gap between polyfluorene and ladder-poly-p-phenylene : Synthesis and characterization of poly-2,8-indenofluorene , 2000 .

[35]  R. H. Friend,et al.  Efficient light-emitting diodes based on polymers with high electron affinities , 1993, Nature.

[36]  Heinz-Georg Nothofer,et al.  Improving the performance of doped π-conjugated polymers for use in organic light-emitting diodes , 2000, Nature.

[37]  R. Friend,et al.  Trap-assisted hole injection and quantum efficiency enhancement in poly(9,9′ dioctylfluorene-alt-benzothiadiazole) polymer light-emitting diodes , 2004 .

[38]  Klaus Meerholz,et al.  Multi-colour organic light-emitting displays by solution processing , 2003, Nature.

[39]  Norbert Koch,et al.  Work Function Independent Hole‐Injection Barriers Between Pentacene and Conducting Polymers , 2005 .

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

[41]  M. Toerker,et al.  OLED manufacturing for large area lighting applications , 2010 .

[42]  Dieter Neher,et al.  Polyfluorene Homopolymers: Conjugated Liquid-Crystalline Polymers for Bright Blue Emission and Polarized Electroluminescence , 2001 .

[43]  C. Chung,et al.  Movement of carrier recombination zone in organic light emitting devices by applied voltage , 2002 .

[44]  Emil J. W. List,et al.  Poly(tetraarylindenofluorene)s: New Stable Blue-Emitting Polymers , 2003 .

[45]  Egbert Zojer,et al.  Efficient Blue‐Light‐Emitting Polymer Heterostructure Devices: The Fabrication of Multilayer Structures from Orthogonal Solvents , 2010, Advanced materials.

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

[47]  C. Tang,et al.  Organic Electroluminescent Diodes , 1987 .

[48]  D. Bradley,et al.  Influence of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) in polymer LEDs , 2006 .

[49]  Stefan Sax,et al.  Ladder-type pentaphenylenes and their polymers: efficient blue-light emitters and electron-accepting materials via a common intermediate. , 2004, Journal of the American Chemical Society.

[50]  R. Friend,et al.  Electroluminescence in poly(3-alkylthienylene)s , 1993 .