Tuning the Microcavity of Organic Light Emitting Diodes by Solution Processable Polymer-Nanoparticle Composite Layers.

In this study, we present a simple method to tune and take advantage of microcavity effects for an increased fraction of outcoupled light in solution-processed organic light emitting diodes. This is achieved by incorporating nonscattering polymer-nanoparticle composite layers. These tunable layers allow the optimization of the device architecture even for high film thicknesses on a single substrate by gradually altering the film thickness using a horizontal dipping technique. Moreover, it is shown that the optoelectronic device parameters are in good agreement with transfer matrix simulations of the corresponding layer stack, which offers the possibility to numerically design devices based on such composite layers. Lastly, it could be shown that the introduction of nanoparticles leads to an improved charge injection, which combined with an optimized microcavity resulted in a maximum luminous efficacy increase of 85% compared to a nanoparticle-free reference device.

[1]  Hong-Gyu Park,et al.  Effects of Gold-Nanoparticle Surface and Vertical Coverage by Conducting Polymer between Indium Tin Oxide and the Hole Transport Layer on Organic Light-Emitting Diodes. , 2015, ACS applied materials & interfaces.

[2]  Daniel Volz,et al.  Bridging the Efficiency Gap: Fully Bridged Dinuclear Cu(I)‐Complexes for Singlet Harvesting in High‐Efficiency OLEDs , 2015, Advanced materials.

[3]  Uli Lemmer,et al.  Influence of the Emission Layer Thickness on the Optoelectronic Properties of Solution Processed Organic Light-Emitting Diodes , 2014 .

[4]  Bumjoon J. Kim,et al.  Au@polymer core-shell nanoparticles for simultaneously enhancing efficiency and ambient stability of organic optoelectronic devices. , 2014, ACS applied materials & interfaces.

[5]  Bumjoon J. Kim,et al.  Simultaneously Enhancing Light Extraction and Device Stability of Organic Light‐Emitting Diodes using a Corrugated Polymer Nanosphere Templated PEDOT:PSS Layer , 2014 .

[6]  J. Kido,et al.  High‐Performance Blue Phosphorescent OLEDs Using Energy Transfer from Exciplex , 2014, Advanced materials.

[7]  Jang‐Joo Kim,et al.  Enhanced light out-coupling of OLEDs with low haze by inserting randomly dispersed nanopillar arrays formed by lateral phase separation of polymer blends. , 2013, Small.

[8]  K. A. Knauer,et al.  Stacked inverted top-emitting green electrophosphorescent organic light-emitting diodes on glass and flexible glass substrates , 2013 .

[9]  Malte C. Gather,et al.  Nano-particle based scattering layers for optical efficiency enhancement of organic light-emitting diodes and organic solar cells , 2013 .

[10]  Tobias D. Schmidt,et al.  Efficiency Analysis of Organic Light-Emitting Diodes Based on Optical Simulations , 2013, IEEE Journal of Selected Topics in Quantum Electronics.

[11]  Karl Leo,et al.  White organic light-emitting diodes: Status and perspective , 2013, 1302.3435.

[12]  Tobias D. Schmidt,et al.  Device efficiency of organic light‐emitting diodes: Progress by improved light outcoupling , 2013 .

[13]  Uli Lemmer,et al.  White organic light emitting diodes with enhanced internal and external outcoupling for ultra-efficient light extraction and Lambertian emission. , 2012, Optics express.

[14]  Uli Lemmer,et al.  Spatial mapping of photocurrents in organic solar cells comprising wedge-shaped absorber layers for an efficient material screening , 2012, Other Conferences.

[15]  N. Thejo Kalyani,et al.  Organic light emitting diodes: Energy saving lighting technology—A review , 2012 .

[16]  Karl Leo,et al.  Efficiency and rate of spontaneous emission in organic electroluminescent devices , 2012 .

[17]  Uli Lemmer,et al.  Efficient waveguide mode extraction in white organic light emitting diodes using ITO-anodes with integrated MgF₂-columns. , 2012, Optics express.

[18]  Zheng-Hong Lu,et al.  Unlocking the full potential of organic light-emitting diodes on flexible plastic , 2011 .

[19]  K. Neyts,et al.  Dipole radiation within one-dimensional anisotropic microcavities: a simulation method. , 2011, Optics express.

[20]  Boris Riedel,et al.  On the interplay of waveguide modes and leaky modes in corrugated OLEDs. , 2011, Optics express.

[21]  Junji Kido,et al.  Multifunctional Materials in High-Performance OLEDs: Challenges for Solid-State Lighting† , 2011 .

[22]  M. Gerken,et al.  Tailored Highly Transparent Composite Hole‐Injection Layer Consisting of Pedot:PSS and SiO2 Nanoparticles for Efficient Polymer Light‐Emitting Diodes , 2011, Advanced materials.

[23]  Soon Moon Jeong,et al.  Light extraction from organic light-emitting diodes enhanced by spontaneously formed buckles , 2010 .

[24]  Dalip Singh Mehta,et al.  A review on the light extraction techniques in organic electroluminescent devices , 2009 .

[25]  Gregor Schwartz,et al.  White organic light-emitting diodes with fluorescent tube efficiency , 2009, Nature.

[26]  Stefan Nowy,et al.  Light extraction and optical loss mechanisms in organic light-emitting diodes: Influence of the emitter quantum efficiency , 2008 .

[27]  Sun Young Lee,et al.  Weak-microcavity organic light-emitting diodes with improved light out-coupling. , 2008, Optics express.

[28]  Stephen R. Forrest,et al.  Enhanced light out-coupling of organic light-emitting devices using embedded low-index grids , 2008 .

[29]  David S. Ginger,et al.  The Changing Face of PEDOT:PSS Films: Substrate, Bias, and Processing Effects on Vertical Charge Transport† , 2008 .

[30]  P. Wai,et al.  Modifications of the exciton lifetime and internal quantum efficiency for organic light-emitting devices with a weak/strong microcavity , 2007 .

[31]  René A. J. Janssen,et al.  Microscopic Understanding of the Anisotropic Conductivity of PEDOT:PSS Thin Films , 2007 .

[32]  Peter Andersson,et al.  The Origin of the High Conductivity of Poly(3,4-ethylenedioxythiophene)−Poly(styrenesulfonate) (PEDOT−PSS) Plastic Electrodes , 2006 .

[33]  Eun Ha Choi,et al.  Enhanced out-coupling factor of microcavity organic light-emitting devices with irregular microlens array. , 2006, Optics express.

[34]  Chihaya Adachi,et al.  100% phosphorescence quantum efficiency of Ir(III) complexes in organic semiconductor films , 2005 .

[35]  Stephen R. Forrest,et al.  White Organic Light‐Emitting Devices for Solid‐State Lighting , 2004 .

[36]  Olle Inganäs,et al.  Optical anisotropy in thin films of poly(3,4-ethylenedioxythiophene)–poly(4-styrenesulfonate) , 2002 .

[37]  O. Inganäs,et al.  Structural anisotropy of poly(alkylthiophene) films , 2000 .

[38]  S. R. Forrest,et al.  High-efficiency fluorescent organic light-emitting devices using a phosphorescent sensitizer , 2000, Nature.

[39]  N. Tessler,et al.  All-polymer optoelectronic devices , 1999, Science.

[40]  Stephen R. Forrest,et al.  Weak microcavity effects in organic light-emitting devices , 1998 .

[41]  L. Pettersson,et al.  Spectroscopic ellipsometry studies of the optical properties of doped poly(3,4-ethylenedioxythiophene): an anisotropic metal , 1998 .

[42]  J. C. Scott,et al.  Enhanced luminance in polymer composite light emitting devices , 1997 .

[43]  H. Bässler,et al.  Microcavity effects in a spin‐coated polymer two‐layer system , 1995 .

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

[45]  Malte C. Gather,et al.  Recent advances in light outcoupling from white organic light-emitting diodes , 2015 .

[46]  Yasunori Taga,et al.  Design of multiwavelength resonant cavities for white organic light-emitting diodes , 2003 .

[47]  K. Neyts,et al.  Semitransparent metal or distributed Bragg reflector for wide-viewing-angle organic light-emitting-diode microcavities , 2000 .