IDEAS home Printed from https://ideas.repec.org/a/nat/nature/v563y2018i7732d10.1038_s41586-018-0695-9.html
   My bibliography  Save this article

Efficient radical-based light-emitting diodes with doublet emission

Author

Listed:
  • Xin Ai

    (College of Chemistry, Jilin University)

  • Emrys W. Evans

    (University of Cambridge)

  • Shengzhi Dong

    (College of Chemistry, Jilin University)

  • Alexander J. Gillett

    (University of Cambridge)

  • Haoqing Guo

    (College of Chemistry, Jilin University)

  • Yingxin Chen

    (College of Chemistry, Jilin University)

  • Timothy J. H. Hele

    (University of Cambridge)

  • Richard H. Friend

    (University of Cambridge)

  • Feng Li

    (College of Chemistry, Jilin University
    University of Cambridge)

Abstract

Organic light-emitting diodes (OLEDs)1–5, quantum-dot-based LEDs6–10, perovskite-based LEDs11–13 and micro-LEDs14,15 have been championed to fabricate lightweight and flexible units for next-generation displays and active lighting. Although there are already some high-end commercial products based on OLEDs, costs must decrease whilst maintaining high operational efficiencies for the technology to realise wider impact. Here we demonstrate efficient action of radical-based OLEDs16, whose emission originates from a spin doublet, rather than a singlet or triplet exciton. While the emission process is still spin-allowed in these OLEDs, the efficiency limitations imposed by triplet excitons are circumvented for doublets. Using a luminescent radical emitter, we demonstrate an OLED with maximum external quantum efficiency of 27 per cent at a wavelength of 710 nanometres—the highest reported value for deep-red and infrared LEDs. For a standard closed-shell organic semiconductor, holes and electrons occupy the highest occupied and lowest unoccupied molecular orbitals (HOMOs and LUMOs), respectively, and recombine to form singlet or triplet excitons. Radical emitters have a singly occupied molecular orbital (SOMO) in the ground state, giving an overall spin-1/2 doublet. If—as expected on energetic grounds—both electrons and holes occupy this SOMO level, recombination returns the system to the ground state, giving no light emission. However, in our very efficient OLEDs, we achieve selective hole injection into the HOMO and electron injection to the SOMO to form the fluorescent doublet excited state with near-unity internal quantum efficiency.

Suggested Citation

  • Xin Ai & Emrys W. Evans & Shengzhi Dong & Alexander J. Gillett & Haoqing Guo & Yingxin Chen & Timothy J. H. Hele & Richard H. Friend & Feng Li, 2018. "Efficient radical-based light-emitting diodes with doublet emission," Nature, Nature, vol. 563(7732), pages 536-540, November.
  • Handle: RePEc:nat:nature:v:563:y:2018:i:7732:d:10.1038_s41586-018-0695-9
    DOI: 10.1038/s41586-018-0695-9
    as

    Download full text from publisher

    File URL: https://www.nature.com/articles/s41586-018-0695-9
    File Function: Abstract
    Download Restriction: Access to the full text of the articles in this series is restricted.

    File URL: https://libkey.io/10.1038/s41586-018-0695-9?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    As the access to this document is restricted, you may want to search for a different version of it.

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. Xin Li & Yi-Lin Wang & Chan Chen & Yan-Yan Ren & Ying-Feng Han, 2022. "A platform for blue-luminescent carbon-centered radicals," Nature Communications, Nature, vol. 13(1), pages 1-8, December.
    2. Xiao Zhang & Mingjian Zeng & Yewen Zhang & Chenyu Zhang & Zhisheng Gao & Fei He & Xudong Xue & Huanhuan Li & Ping Li & Gaozhan Xie & Hui Li & Xin Zhang & Ningning Guo & He Cheng & Ansheng Luo & Wei Zh, 2023. "Multicolor hyperafterglow from isolated fluorescence chromophores," Nature Communications, Nature, vol. 14(1), pages 1-9, December.
    3. Xiao-Xiang Chen & Jia-Tong Li & Yu-Hui Fang & Xin-Yu Deng & Xue-Qing Wang & Guangchao Liu & Yunfei Wang & Xiaodan Gu & Shang-Da Jiang & Ting Lei, 2022. "High-mobility semiconducting polymers with different spin ground states," Nature Communications, Nature, vol. 13(1), pages 1-9, December.
    4. Cao Fang & Chang Xu & Wei Zhang & Meng Zhou & Dong Tan & Lixia Qian & Daqiao Hu & Shan Jin & Manzhou Zhu, 2024. "Dual-quartet phosphorescent emission in the open-shell M1Ag13 (M = Pt, Pd) nanoclusters," Nature Communications, Nature, vol. 15(1), pages 1-10, December.
    5. Ansheng Luo & Jingru Zhang & Dongjie Xiao & Gaozhan Xie & Xinqi Xu & Qingxian Zhao & Chengxi Sun & Yanzhang Li & Zehua Zhang & Ping Li & Shouhua Luo & Xiaoji Xie & Qiming Peng & Huanhuan Li & Runfeng , 2024. "Efficient metal free organic radical scintillators," Nature Communications, Nature, vol. 15(1), pages 1-8, December.
    6. Hong Xiang & Yongfu Li & Qinglong Liao & Lei Xia & Xiaodong Wu & Huang Zhou & Chunmei Li & Xing Fan, 2024. "Recent Advances in Smart Fabric-Type Wearable Electronics toward Comfortable Wearing," Energies, MDPI, vol. 17(11), pages 1-36, May.

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:nat:nature:v:563:y:2018:i:7732:d:10.1038_s41586-018-0695-9. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Sonal Shukla or Springer Nature Abstracting and Indexing (email available below). General contact details of provider: http://www.nature.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.