Advanced Optical Materials
Advanced Optical Materials
4 years ago

Highly Efficient Nondoped Near-Ultraviolet Electroluminescence with an External Quantum Efficiency Greater Than 6.5% Based on a Carbazole–Triazole Hybrid Molecule with High and Balanced Charge Mobility

Highly Efficient Nondoped Near-Ultraviolet Electroluminescence with an External Quantum Efficiency Greater Than 6.5% Based on a Carbazole–Triazole Hybrid Molecule with High and Balanced Charge Mobility
Yuyu Pan, Shanfeng Xue, Wenjun Yang, Yuansheng Lu, Shian Ying, Xu Qiu, Cheng Gu, Qikun Sun
Low charge injection and unbalanced carrier transport are unfavorable factors for highly efficient near-ultraviolet (NUV) electroluminescence (EL) emitters. The construction of weak donor- and acceptor-containing fluorophores has been utilized as a common solution to these issues. Few fluorescent emitters simultaneously exhibiting NUV emission and high/balanced charge-transport properties have been reported. Herein, a new 1D donor–π–acceptor molecule 9-(4′-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)-[1,1′-biphenyl]-4-yl)-9H-carbazole named PCZTZ consisting of 9-phenylcarbazole as a donor and 2,3,4-triphenyl-1,2,4-triazole as an acceptor with a biphenyl π-bridge is constructed. The backbone-twisted PCZTZ exhibits not only strong solid-state NUV fluorescence but also high and balanced hole and electron mobilities (both up to 10−4 cm2 V−1 s−1), benefiting from the 3D supramolecular H-bonding network containing strong CH⋯N interactions. Remarkably, a fabricated nondoped light-emitting diode (OLED) emits 408 nm bright NUV light with a maximal external quantum efficiency of 6.57% and Commission Internationale de L'Eclairage coordinates of (0.17, 0.07). Thus, this OLED is the most efficient NUV OLED reported thus far. These results provide a valuable strategy for the design of highly efficient NUV EL emitters by modulating the linking positions of carbazole and triazole on a biphenyl bridge. A near-ultraviolet (NUV) fluorescent emitter exhibiting a high and balanced carrier mobility of 10−4 cm2 V−1 s−1 is achieved using biphenyl-bridged carbazole and triazole units. The nondoped organic light-emitting diode (OLED) emits 408 nm bright NUV light with a maximal external quantum efficiency of 6.57% and Commission Internationale de L'Eclairage coordinates of (0.17, 0.07), representing the most efficient NUV OLED reported thus far.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/adom.201700747

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.