Recent advances in Blue-Emitting Iridium(III) Complexes Featuring 2-(2,4-Difluorophenyl)pyridine as the Cyclometalating Ligand

Nur Khaliesa Zulkarnaen; Noorshida Mohd Ali

doi:10.22146/ijc.106512

Recent advances in Blue-Emitting Iridium(III) Complexes Featuring 2-(2,4-Difluorophenyl)pyridine as the Cyclometalating Ligand

https://doi.org/10.22146/ijc.106512

Nur Khaliesa Zulkarnaen⁽¹⁾, Noorshida Mohd Ali^(2*)

(1) Department of Chemistry, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris, Tanjong Malim 35900, Perak, Malaysia
(2) Department of Chemistry, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris, Tanjong Malim 35900, Perak, Malaysia
(*) Corresponding Author

Abstract

The significance of blue emitters in the realization of cutting-edge organic light-emitting diode (OLED) displays cannot be overstated, leading to considerable efforts aimed at synthesizing intense blue phosphorescent Ir(III) complexes that are stable for use as dopants. Nevertheless, the quest for highly effective blue phosphorescent Ir(III) complexes remains fraught with challenges. Bis(2-(4,6-difluorophenyl)pyridinato-C²,N)(picolinato)iridium(III) (FIrpic), which employs 2-(2,4-difluorophenyl)pyridine (F₂ppy) as the cyclometalating ligand and picolinic acid as the ancillary ligand, serves as a benchmark for blue phosphorescent Ir(III) complexes because of its outstanding performance in OLED devices, yet it still exhibits several limitations. Consequently, the pursuit of more effective blue phosphorescent iridium complexes remains a priority. In recent years, advancements in the field have focused on blue phosphorescent Ir(III) complexes utilizing a variety of cyclometalated ligands in conjunction with bidentate ancillary ligands, leading to extensive investigation. This discussion will highlight and analyze the most recent progress in designing and preparing those complexes, particularly utilizing F₂ppy alongside diverse bidentate ancillary ligands. Future studies are encouraged to focus on structural modification of the F₂ppy cyclometalating ligand, particularly with the combination of suitable ancillary ligands, to improve further color purity of blue-emitting Ir(III) complexes and their photophysical performance.

Keywords

blue phosphorescent; Ir(III) complexes; ancillary ligand; 2-(2,4-difluorophenyl)pyridine; OLED

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DOI: https://doi.org/10.22146/ijc.106512