Tuning the photophysical properties of cationic Ir(III) complexes containing oxazoline-based ancillary ligand

ABSTRACT

Two new cationic iridium(III) complexes were synthesized and characterized using oxazoline based ancillary ligand, namely, [Ir(dfppy)₂(ibpo)]PF₆ (Complex 1) and [Ir(ppz)₂(ibpo)]PF₆ (Complex 2), where dfppy is 2-(2,4-difluorophenyl)pyridine, ppz is 1-phenylpyrazole, and ibpo is (S,S)-2,2’-isopropylidene-bis(4-phenyl-2-oxazoline). The absorption, emission, and cyclic voltammetry of the complexes were investigated. Photoluminescence (PL) emission spectra of the complexes in acetonitrile solutions were measured which displays intense photoluminescence maxima in blue (Complex 1) and green (Complex 2) region of the visible spectrum. Light-emitting electrochemical cells (LECs) were fabricated utilizing these complexes and investigated their electroluminescent properties. The devices based on both complexes exhibit green electroluminescence with Commission Internationale de l'Eclairage (CIE) coordinates of (0.46, 0.49) and (0.38, 0.50) for Complexes 1 and 2, respectively.

KEYWORDS:

• Iridium complexes
• green emissions
• photophysical properties
• oxazoline

Funding

This work was supported by a 2-Year Research Grant of Pusan National University and the Brain Korea (BK) 21 Plus project.