Extremely efficient flexible organic light-emitting diodes with modified graphene anode

ABSTRACT Although graphene films have a strong potential to replace indium tin oxide anodes in organic light-emitting diodes (OLEDs), to date, the luminous efficiency of OLEDs with graphene

anodes has been limited by a lack of efficient methods to improve the low work function and reduce the sheet resistance of graphene films to the levels required for electrodes1,2,3,4. Here,

we fabricate flexible OLEDs by modifying the graphene anode to have a high work function and low sheet resistance, and thus achieve extremely high luminous efficiencies (37.2 lm W–1 in

fluorescent OLEDs, 102.7 lm W–1 in phosphorescent OLEDs), which are significantly higher than those of optimized devices with an indium tin oxide anode (24.1 lm W–1 in fluorescent OLEDs,

85.6 lm W–1 in phosphorescent OLEDs). We also fabricate flexible white OLED lighting devices using the graphene anode. These results demonstrate the great potential of graphene anodes for

use in a wide variety of high-performance flexible organic optoelectronics. Access through your institution Buy or subscribe This is a preview of subscription content, access via your

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* Learn about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS FLEXIBLE HIGH-PERFORMANCE GRAPHENE HYBRID PHOTODETECTORS

FUNCTIONALIZED WITH GOLD NANOSTARS AND PEROVSKITES Article Open access 18 December 2020 FLEXIBLE AND MONOLITHICALLY INTEGRATED MULTICOLOR LIGHT EMITTING DIODES USING MORPHOLOGY-CONTROLLED

GAN MICROSTRUCTURES GROWN ON GRAPHENE FILMS Article Open access 12 November 2020 FLEXIBLE PEROVSKITE LIGHT-EMITTING DIODES: RECENT PROGRESS, APPLICATIONS AND CHALLENGES Article Open access

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and Global Frontier Research Center for Advanced Soft Electronics through the National Research Foundation of Korea (NRF), funded by the Ministry of Education, Science and Technology (nos.

2009-0067533, 2009-0075025, 2011-0006268 and 2009-0090177). This research was also supported by the Converging Research Center Program through the Ministry of Education, Science and

Technology (no. 2010K001431). AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang,

790-784, Gyungbuk, Republic of Korea Tae-Hee Han, Mi-Ri Choi, Seong-Hoon Woo & Tae-Woo Lee * SKKU Advanced Institute of Nanotechnology (SAINT), Center for Human Interface Nano Technology

(HINT) and School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, 440-746, Gyeonggi-do, Republic of Korea Youngbin Lee, Sang-Hoon Bae & Jong-Hyun Ahn *

Department of Chemistry, Seoul National University, Seoul, 151-747, Republic of Korea Byung Hee Hong Authors * Tae-Hee Han View author publications You can also search for this author

inPubMed Google Scholar * Youngbin Lee View author publications You can also search for this author inPubMed Google Scholar * Mi-Ri Choi View author publications You can also search for this

author inPubMed Google Scholar * Seong-Hoon Woo View author publications You can also search for this author inPubMed Google Scholar * Sang-Hoon Bae View author publications You can also

search for this author inPubMed Google Scholar * Byung Hee Hong View author publications You can also search for this author inPubMed Google Scholar * Jong-Hyun Ahn View author publications

You can also search for this author inPubMed Google Scholar * Tae-Woo Lee View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS T.-H.H. designed

and conducted most of the experiments, analysed the data and prepared the manuscript. Y.L. and S.-H.B. conducted experiments regarding graphene growth, patterning of graphene anodes and

characterization. S.-H.W. and M.-R.C. helped with the OLED fabrication experiments. B.H.H. interpreted data and suggested improvements to the manuscript. J.-H.A. designed the graphene

experiments, analysed data and prepared the manuscript. T.-W.L. initiated the study, designed all the experiments, analysed the data and prepared the manuscript. All authors discussed the

results and contributed to the paper. CORRESPONDING AUTHORS Correspondence to Jong-Hyun Ahn or Tae-Woo Lee. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing financial

interests. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary information (PDF 2635 kb) RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE

Han, TH., Lee, Y., Choi, MR. _et al._ Extremely efficient flexible organic light-emitting diodes with modified graphene anode. _Nature Photon_ 6, 105–110 (2012).

https://doi.org/10.1038/nphoton.2011.318 Download citation * Received: 11 July 2011 * Accepted: 08 November 2011 * Published: 10 January 2012 * Issue Date: February 2012 * DOI:

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