Constructing deep-blue bis-tridentate Ir(III) phosphors with fluorene-based dianionic chelates

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

11 Scopus Citations
View graph of relations


  • Shao-Fei Ni
  • Sheng Fu Wang
  • Li-Wen Fu
  • Han-Yan Tsai


Original languageEnglish
Pages (from-to)1318-1325
Journal / PublicationJournal of Materials Chemistry C
Issue number4
Online published9 Dec 2020
Publication statusPublished - 28 Jan 2021


High efficiency and stable blue phosphors have been a persistent pursuit in the field of organic light-emitting diodes (OLEDs). Bis-tridentate Ir(III) complexes are considered as promising alternatives because of their excellent emission efficiency and good photostability. However, the emission colors of photostable bis-tridentate Ir(III) emitters reported so far do not reach the deep blue region. Herein, fluorene is introduced in the design of blue bis-tridentate Ir(III) complexes. By modifying a fluorene-based dianionic chelate with tert-butyl, methoxy, pyrrolidinyl and triazolyl appendages, five blue emitting bis-tridentate Ir(III) phosphors were successfully designed and prepared. Emissions of the new phosphors exhibited a gradual blue shift from the sky blue to the deep blue region according to the electron donating abilities of the added substituents. A deep blue OLED was successfully fabricated based on Flu-4 and presented an excellent maximum external quantum efficiency of 22.3% with CIE coordinates of (0.17, 0.19), which are comparable to the state-of-the-art deep blue phosphors.

Citation Format(s)